Induced seismicity is likely a major obstacle in front of the widespread deployment of geoenergy applications, such as geothermal energy or geologic carbon storage (GCS), which are indispensable components of efforts to mitigate the climate change emergency. Induced earthquakes may jeopardize the integrity of subsurface structures and, if felt at the surface, negatively impact the public perception of geoenergy projects. Thus, the effective and safe use of the subsurface to provide clean and sustainable energy and reduce atmospheric carbon emissions needs to properly address the risks and hazards posed by induced seismicity. In this Outstanding Early Career Scientist ‎Award Lecture of the ERE‎ Division, I discuss some important topics of induced seismicity in low-carbon geoenergies. First, I explain the potential mechanisms of seismic events that are unexpectedly induced far away from and/or long after operations related to geothermal energy developments. Such seismic sequences have been found problematic because of partial loss of control over their management. In particular, ‎thermal stress is key in reactivating distant faults from a fluid circulation doublet after several years ‎of operation in hydraulically bounded and unbounded hot deep sedimentary aquifers. The observed delays can be explained by the relatively large characteristic time scales of thermal effects (small thermal diffusivity). In enhanced ‎geothermal systems, a sequence of processes, which can be identified when explicitly including fractures in numerical models, may give rise to post-injection seismicity. The stabilizing effect of poroelastic stress generated during reservoir ‎stimulation rapidly attenuates after stopping injection, while the injection overpressure gradually diffuses ‎away, which could bring distant faults to slip conditions with time delays as long as several months. Interestingly, bleed-off, i.e., ‎flow back to relieve wellbore pressure,‎ as an industrial practice to prevent post-injection seismicity may not effectively work under certain conditions. This is because the ‎stimulated fractures become progressively less responsive to hydraulic perturbations with distance from ‎the wellbore. In the second part of my presentation, I discuss induced seismicity within GCS at the gigatonne scale. Analysis of data from the global, multiphysics database of induced seismicity underscores some similarities between large-scale GCS and massive wastewater disposal that led to a drastic rise in seismic activity in central and eastern US in the 2010s – not to negate fundamental differences between the two technologies. Although GCS at the megatonne scale has been extensively demonstrated, its scale-up could face elevated risk of induced seismicity. We have developed the open-source tool CO2BLOCKSEISM that employs simplified physics models for screening subsurface CO₂ storage resources at regional scales constrained by the risk of induced seismicity. The tool’s application is shown within the Utsira storage unit in the North Sea. Induced seismicity draws a more restrictive and ‎realistic limit to the storage resource use at regional than at single-site scales. I conclude that reliable methodologies for induced seismicity forecasting and mitigation should be developed in light of the underlying physics and continuous characterization of the subsurface during operations to safely unlock the huge potential of the subsurface for a timely approach toward climate targets.

How to cite: Rahimzadeh Kivi, I., Makhnenko, R., Min, K.-B., Rutqvist, J., Carrera, J., Krevor, S., and Vilarrasa, V.: Energy transition and the challenge of induced seismicity, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13579, https://doi.org/10.5194/egusphere-egu25-13579, 2025.

The sustainable development of microalgae bioenergy systems faces dual challenges: identifying suitable cultivation locations and optimizing production parameters across diverse environmental conditions. Building upon our previous research on global marginal land assessment and machine learning applications in microalgae cultivation, this study presents a novel multi-modal artificial intelligence framework that combines deep learning, machine learning, and large language models (LLMs) to address these challenges comprehensively. Our approach integrates three key components: (1) a hybrid deep learning network with attention mechanisms for biomass productivity prediction across different geographical and climatic conditions, (2) LLM-powered intelligent analysis of historical experimental data (1980-2024) for parameter optimization and pattern discovery, and (3) advanced machine learning algorithms for identifying and assessing marginal land suitability. Initial spatial analysis has identified approximately 7.37 million square kilometers of marginal lands suitable for microalgae cultivation, particularly in equatorial and low-latitude regions, with Australia, Kazakhstan, Sudan, Brazil, the United States, and China showing significant potential. Our previous machine learning models demonstrated that Photobioreactors (PBRs) achieved a global average daily biomass productivity of 142.81mgL−1d−1, while Open Ponds reached 122.57mgL−1d−1. Building on these findings, our new deep learning framework shows a 35% improvement in productivity prediction accuracy compared to traditional methods, achieving a test R² of 0.94. The LLM-based data mining approach reveals novel correlations between cultivation parameters and system performance across different geographical contexts, while accounting for various cultivation methods. The framework suggests that optimal cultivation strategies could potentially increase biomass yields by 40% while minimizing resource inputs, with projected annual production reaching 99.54 gigatons of microalgae biomass when utilizing suitable marginal lands. This biomass could be transformed into 64.70 gigatons of biodiesel, equivalent to 58.68 gigatons of traditional diesel, while sequestering 182.16 gigatons of CO₂. The integration of LLMs for experimental data analysis represents a significant advancement in understanding complex parameter interactions and optimization opportunities. This integrated approach not only advances our understanding of microalgae cultivation optimization but also provides practical insights for sustainable land management and renewable energy development, while addressing critical challenges in climate change mitigation through bioenergy production and carbon sequestration.

How to cite: Chen, M., Ngo, H. H., and Zhang, Q.: Unlocking Global Bioenergy Potential: Multi-Modal AI Framework for Microalgae Cultivation on Marginal Lands with Intelligent Data Mining, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-1447, https://doi.org/10.5194/egusphere-egu25-1447, 2025.

The superimposed basins in western China have undergone multiple periods of tectonic changes and cycles of oil and gas accumulation, and the distribution patterns of oil and gas are very complex, which limits the accurate understanding of the mechanisms of oil and gas accumulation. In this paper, Yuqi area in Tarim Basin is taken as the research area, and based on the geological background, fluid inclusion-homogenization temperature, hydrocarbon inclusion abundance analysis, reservoir quantitative fluorescence technology, infrared spectrum, crude oil geochemical analysis, reservoir asphalt identification and other technologies, the Ordovician-Triassic oil and gas accumulation, migration and adjustment process in Yuqi area is studied. The results indicate that the Ordovician system in the study area developed oil injection during the Late Caledonian, Yanshanian, and Himalayan periods. The Triassic system only had oil injection during the Himalayan period, slightly later than the Ordovician system during the same period. The crude oil injected by the Ordovician in the late Caledonian period was biodegraded into heavy oil and carbonaceous bitumen due to tectonic uplift. Light oil from the Yuertus Formation source rock during the Yanshan-Himalayan period was vertically injected into the Ordovician reservoir along activated faults, and then mixed and transformed early heavy oil reservoirs through lateral adjustment along karst. A certain range of light oil reservoirs were formed in the heavy oil reservoir area. In the late Himalayan period, the light/heavy oil reservoirs mixed and filled by the Ordovician system were locally adjusted upwards along faults to the Triassic system, making the crude oil of the Triassic system, which had stable structures and no degradation conditions, similar to the crude oil of the Ordovician system in terms of crude oil density, maturity, inclusion abundance, biodegradation characteristics, and partially mix with late mature oil and gas that migrated along the Luntai fault-sand body, forming the sporadic distribution characteristics of light and heavy oil reservoirs in the Triassic system today. Therefore, a reservoir formation model of "vertical transport along faults, lateral adjustment along karst, strong degradation, and differential superposition" was established for the Ordovician, and " T-shaped transport along fault-sand and late stage reservoir formation " was established for the Triassic in the Yuqi area.The research have important guiding and reference significance for shallow-deep oil and gas exploration in the Yuqi area.

How to cite: Su, Y., Liu, H., Wang, S., Wang, J., and Zhao, Z.: Multi-layer Hydrocarbon Accumulation Model in Yuqi area, Tarim Basin, China, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-1746, https://doi.org/10.5194/egusphere-egu25-1746, 2025.

The traditional atmospheric correction models employed with the near-infrared iterative schemes inaccurately estimate aerosol radiance at high solar zenith angles (SZAs), leading to a substantial loss of valid products for dawn or dusk observations by the geostationary satellite ocean color sensor. To overcome this issue, we previously developed an atmospheric correction model suitable for open ocean waters observed by the first geostationary satellite ocean color imager (GOCI) under high SZAs. This model was constructed based on a dataset from stable open ocean waters, which makes it less suitable for coastal waters. In this study, we developed a specialized atmospheric correction model (GOCI-II-NN) capable of accurately retrieving the water-leaving radiance from GOCI-II observations in coastal oceans under high SZAs. We utilized multiple observations from GOCI-II throughout the day to develop the selection criteria for extracting the stable coastal water pixels and created a new training dataset for the proposed model. The performance of the GOCI-II-NN model was validated by in-situ data collected from coastal/shelf waters. The results showed an Average Percentage Difference (APD) of less than 23% across the entire visible spectrum. In terms of the valid data and retrieval accuracy, the GOCI-II-NN model was superior to the traditional near-infrared and ultraviolet atmospheric correction models in terms of accurately retrieving the ocean color products for various applications, such as tracking/monitoring of algal blooms, sediment dynamics, and water quality among other applications.

How to cite: Li, H., He, X., Palanisamy, S., Bai, Y., and Xuchen, J.: Atmospheric correction of geostationary ocean color imager data over turbid coastal waters under high solar zenith angles, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2102, https://doi.org/10.5194/egusphere-egu25-2102, 2025.

Over the past fifty years, the Indian Ocean has experienced a pervasive warming trend, prompting investigations into the causative factors and consequential impacts at a basin-wide scale. Research analyzing sea surface temperature (SST) suggests that the western Indian Ocean has been undergoing warming for more than a century. The increase in SST has triggered a range of effects, including alterations in surface pressure distribution, resulting in variable wind patterns, sea-level rise, and other associated outcomes. Understanding the variability in wind speed holds practical significance, including estimating wind power potential for specific geographic regions and developing future projections for wind wave climates to aid in the planning of coastal activities and coastal zone management. The World Climate Research Programme (WCRP) within the Intergovernmental Panel on Climate Change (IPCC) plays a pivotal role in disseminating comprehensive insights into the past, present, and future trajectories of climate change for the scientific community. The CMIP6 project, introduces a spectrum of shared socio-economic pathways (SSP) projecting radiative forcing values ranging from 1.9 to 8.5 W/m² by the end of the century. For a comprehensive understanding of future climate projections, a thorough evaluation and skill assessment of General Circulation Models (GCMs) within the CMIP6 project, specifically regarding their ability to simulate wind speed, is imperative. In this study, BCC-CSM2-MR model has been leveraged to project future changes in the offshore wind energy potential over the Arabian sea. The projections of wind speed at a height of 50 meters using the BCC-CSM2-MR, on the Arabian Sea within a span of three distinct periods: Near-future (2026-2050), Mid-future (2051- 60 2075), and Far-future (2076-2100) and for two distinct Shared Socio-economic Pathway (SSP) scenarios, namely SSP1-2.6 and SSP3-7.0, have been estimated in this study. The overall trend indicates that wind speed over the Arabian Sea remains relatively constant, showing no significant changes. However, a subtle increase is discernible on the western side of the Arabian Sea, particularly near the Oman coast, evident in the SSP3-7.0 scenario. The Projected change in the wind power density (WPD) for the three distinct period change are evaluated keeping the historical wind data from 1990-2014 as a reference. The WPD is increasing by 10% over the Arabian sea for SSP1-2.6 for near-future (2026- 2050), 8% for mid-future (2051-2075) and 6% for far-future (2076-2100) with respect to historical wind speed (1990-2014). But for SSP3-7.0 the wind speed is showing a decline of 2%to 4 % from near-future to far-future. Correspondingly, wind power density exhibited spatial changes over the Arabian Sea, with the western side showing an increase under SSP1-2.6 and a decrease under SSP3-7.0

Keywords: Wind Speed, Wind Power Density, CMIP6, Arabian Sea, Offshore Wind Energy, Climate Change.

How to cite: Ansari, S. and Behera, M. R.: Impact of Climate Change on Offshore Wind Energy Potential over the Arabian Sea using CMIP6 Future Projection., EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2114, https://doi.org/10.5194/egusphere-egu25-2114, 2025.

Oil and gas reserves are important resources for human survival, directly related to future oil and gas production and the sustainable development and utilization of energy. It is crucial to strengthen the understanding and judgment of the growth trend of oil and gas reserves. The prediction of the growth trend of oil and gas reserves is a forward-looking research work, and its prediction results will directly affect the direction of future oil and gas exploration and investment. To explore new methods for predicting oil and gas reserves, promote sustainable development and utilization of energy, and provide theoretical basis for oil and gas exploration and development. For this purpose, taking the Llanos Basin in South America as an example, combined with comprehensive data such as oil and gas reserve growth data and various geological characteristics, a combination of Analytic Hierarchy Process and ARIMA algorithm was proposed to predict and verify the oil and gas reserves in the Llanos Basin. Firstly, the Analytic Hierarchy Process is used to perform weight analysis on various geological factors in the Llanos Basin. Analysis shows that structural evolution factors have a significant impact on the growth of oil and gas reserves. On this basis, ARIMA algorithm is applied to perform hierarchical prediction verification on each construction unit of Llanos Basin. The results indicate that the combination prediction method has been validated to have good prediction performance.

How to cite: Li, H. and Zhang, L.: oil and gas reserve prediction method based on Analytic Hierarchy Process and ARIMA algorithm: A case study of the Llanos Basin in South America, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2507, https://doi.org/10.5194/egusphere-egu25-2507, 2025.

The rapid expansion of global renewable energy systems has led to a significant increase in raw material extraction, manufacturing and the potential generation of substantial new types of waste. However, a comprehensive analysis of future trends and distribution of emerging renewable energy waste (ReWaste) is lacking. This study introduces an integrated model, GCAM-ReWaste, which incorporates global change analysis model (GCAM) with material flow analysis (MFA) to address this gap, covering 20 renewable energy technologies across 30 regions worldwide. Additionally, the model integrates life cycle assessment (LCA) to explore the environmental and economic impacts of treating the upcoming ReWaste streams under three recycling scenarios. The results reveal a 37-fold surge in global ReWaste, rising from 2.8 million metric tons (Mt) in 2020 to 102.7 Mt by 2050, cumulating in a staggering total of 1,094 Mt to achieve the net-zero emissions target. China, the United States, the European Union, and India will account for 66% of the global ReWaste total. The ReWaste is expected to contain substantial recyclable materials, which could potentially cover 45%-75% of their demand by 2050. The thriving ReWaste recycling market could reach a value of US$780–1,223 billion and contribute to a reduction in carbon emissions by as much as 900–2,082 Mt CO₂-equivalent. Our findings highlight the challenges associated with ReWaste management, including the dispersed distribution of waste generation, the diversity and ongoing evolution of renewable technologies, financial viability and the immaturity of recycling technologies and policies. We advocate for concerted efforts from all stakeholders throughout the entire lifecycle of renewable energy, including manufacturers, recyclers and policy-makers, to effectively address the impending surge in ReWaste.

How to cite: Yang, Y. and Wang, P.: Addressing Renewable Energy Waste: Scale, Challenges, and Recycling Impacts, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2811, https://doi.org/10.5194/egusphere-egu25-2811, 2025.

The industrial sector is a major contributor to greenhouse gas emissions, responsible for around 24% of global emissions in 2019. According to the World Resources Institute (WRI), to meet short-term climate targets aligned with a 1.5°C increase in global temperatures, the share of electricity in the final energy demand of the industrial sector must increase to 35-43% by 2030, 51-54% by 2040, and 60-69% by 2050.
CITIC Dicastal, the world’s largest producer of automotive aluminum wheels, operates 21 manufacturing facilities globally. These facilities, which collectively produce around 80 million aluminum wheels and 120,000 tons of aluminum castings annually, have significant energy needs due to their high-volume production. For instance, the newly opened plant in Morocco is designed to operate using green energy instead of relying solely on natural gas, utilizing high-temperature furnaces for aluminum alloy melting. This requires a reliable energy source to meet the plant's energy demands.
This study provides tailored recommendations for enhancing efficiency and reducing environmental impact by exploring cogeneration, where both heat and electricity are produced simultaneously. Renewable electricity from photovoltaic and wind sources is used, while water for hydrogen electrolysis is sourced from a water treatment station. For energy storage, batteries are employed for short-term storage, while hydrogen storage is utilized for long-term storage. A portion of the hydrogen produced is burned to generate heat, while the remaining hydrogen is used in a fuel cell to generate electricity. We compare different hydrogen combustion systems and green hydrogen technologies using a multi-scenario analysis approach.
We find that direct-fired systems are prioritized for processes requiring rapid heating, while indirect-fired systems are suitable for applications sensitive to direct flame contact. Fluidized bed combustion systems are effective for burning various fuels, including low-quality fuels. For CITIC Dicastal's decarbonization strategy, selecting electrolyzer technology should consider hydrogen production scale, purity requirements, and integration with existing processes. Alkaline electrolyzers are recommended for large-scale hydrogen production due to their cost-effectiveness and maturity. Proton Exchange Membrane (PEM) electrolyzers are ideal for applications requiring high-purity hydrogen and quick response times. Solid Oxide Electrolyzer Cells (SOECs) offer promising solutions in environments where waste heat can be utilized. We also find that compressed hydrogen storage is particularly advantageous for immediate energy needs, while liquid and solid-state options provide solutions for long-term storage and safety. The study indicates that PEM fuel cells offer quick response times ideal for backup power but come with higher costs. Alkaline Fuel Cells (AFCs) provide a lower-cost alternative but are sensitive to carbon dioxide. Phosphoric Acid Fuel Cells (PAFCs) are suitable for cogeneration but have longer start-up times. Molten Carbonate Fuel Cells (MCFCs) and Solid Oxide Fuel Cells (SOFCs) excel in efficiency, but face challenges related to high-temperature operations.
Overall, this research underscores the potential of integrating advanced hydrogen technologies into CITIC Dicastal’s operations to achieve significant decarbonization goals.

How to cite: Bouramdane, A.-A. and Degiovanni, A.: Cost-Effective and Sustainable Pathways for Green Industrial Cogeneration: Replacing Natural Gas with Hydrogen in Dicastal's Operations, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3246, https://doi.org/10.5194/egusphere-egu25-3246, 2025.

Hydrogen production through autothermal reforming with carbon capture and storage (ATR-CCS) is often considered more reliable and scalable than renewable energy-based hydrogen production, especially when intermittent sources struggle to provide a constant power supply. However, ATR-CCS presents challenges related to the cost and complexity of carbon capture and storage, as well as dependence on fossil fuels, limiting its long-term sustainability. It also requires significant infrastructure and a large amount of energy, which can impact its efficiency and profitability in regions aiming to reduce carbon emissions.
Hydrogen production through renewable energy electrolysis faces obstacles due to intermittency. For instance, solar production varies with temperature and cloud cover, wind energy is unpredictable, and marine sources (waves, tides) present fluctuations, although tidal energy is more predictable. Biomass energy is more stable but depends on raw material availability, while geothermal energy, though stable, can experience variations due to operational issues or resource availability.
Proton exchange membrane water electrolyzers (PEMWE) and alkaline electrolyzers are well-suited for renewable energy sources, as they adjust well to rapid energy supply variations. PEMWE use an electric current to split water into hydrogen and oxygen, offering high hydrogen purity due to a solid polymer membrane. However, they are more expensive and sensitive to impurities in the water. Alkaline electrolyzers, developed earlier and more robust, are less responsive to energy variations but provide a stable solution when energy supply is consistent. They are less expensive in the long run and suitable for large-scale installations.
However, these sudden or irregular variations in energy supply present several technical challenges. First, when energy supply changes abruptly, the temperature inside the electrolyzer can exceed optimal levels (thermal spike) or fall below them (thermal dip), potentially damaging internal components and reducing the overall efficiency of the electrolysis process. Moreover, after an energy fluctuation, the system takes time to stabilize its temperature and pressure, leading to irregular hydrogen production and efficiency losses. These challenges require the use of advanced control strategies capable of real-time regulation of key system parameters (such as current, voltage, and temperature), accounting for different energy fluctuation scenarios (progressive or abrupt). Unlike traditional control systems (simple thermostats or Proportional-Integral-Derivative “PID” control), these approaches (such as model-free control, H-infinity, or optimized PID) ensure better responsiveness and accuracy, guaranteeing stable efficiency even with fluctuations, thereby reducing temperature overshoots and speeding up the stabilization time for electrolyzers. For example, model-free control reduces temperature overshoots and accelerates stabilization time by at least 15 minutes for alkaline electrolyzers.

How to cite: Bouramdane, A.-A., Ait Ziane, M., and Zasadzinski, M.: Strategies for Controlling Blue and Green Hydrogen Flow Rate for Optimal Integration, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3697, https://doi.org/10.5194/egusphere-egu25-3697, 2025.

     With the continuous development of deep oil and gas exploration, the phenomenon of oil and gas enrichment near prematurely failed source faults in deep formations has been revealed. However, the mechanism of how these prematurely failed faults open to transport hydrocarbon is not yet clearly understood, and there is a lack of quantitative evaluation of their transport capacity. This study takes the Lufeng 13 Sag in the Pearl River Mouth Basin as an example. Based on 3D seismic data, software simulation, and mudstone plastic deformation experiments, it analyzes the reactivation mechanism of prematurely failed faults and evaluates their vertical transport capacity, revealing the role of these faults in deep hydrocarbon enrichment. The study shows that the transport capacity of prematurely failed faults is negatively correlated with the normal stress on the fault plane during the reservoir-forming period and positively correlated with the ultimate pressure for mudstone plastic deformation. When the normal stress on the fault plane during the reservoir-forming period is less than 13.9 MPa, the buoyancy of hydrocarbon can overcome the normal stress on the fault plane at the upper interface of the source rock, allowing hydrocarbon to migrate upward along the fault. When the ultimate pressure for mudstone plastic deformation is greater than 18.5 MPa, the pressure on the fault plane is less than the ultimate pressure for mudstone plastic deformation, and the argillaceous components in the fault zone do not undergo plastic deformation and flow. The leakage spaces left in the fault zone are not blocked, and no seal is formed vertically. Based on the normal stress on the fault plane during the reservoir-forming period and the ultimate pressure for mudstone plastic deformation, a vertical transport coefficient (K) for prematurely failed faults is established. When K is less than 1.1, the prematurely failed fault has vertical transport capacity during the reservoir-forming period.

How to cite: Cao, X., Liu, H., Peng, G., and Long, Z.: Study on the Vertical Transport Capacity of Prematurely Failed Faults in Deep Oil and Gas Enriched Areas: A Case Study of Lufeng 13 Sag in the Pearl River Mouth Basin, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4960, https://doi.org/10.5194/egusphere-egu25-4960, 2025.

Urban mobility is undergoing significant technological transformations, with the application of sharing and autonomous driving technologies. It will reshape people's travel behavior patterns. However, the direction of the change is heavily influenced by urban spatial features, including the density of population, the distance between residents and job, the public transportation infrastructure, the diversity of local place, as well as the urban form. In response to this evolving landscape, this study integrates macro-level predictions from IAM with micro-level features of urban space to reassess the trends in travel demand in China up to the years 2030 and 2060. The findings indicate that, when considering the micro-features of existing urban spaces, projections based on future comprehensive system evaluation models may significantly overestimate the volume of car travel, so as to the demands on private cars. Variations between different regions and within the same city, particularly between new and old neighborhoods, further reveal the substantial potential for reducing car travel through urban planning and management. Consequently, this research proposes the design and experimentation of new business models for intelligent and shared mobility that align with the micro-spatial configuration of cities. It explores more sustainable pathways for the low-carbon transformation of urban transportation, aiming to harness the unique spatial attributes of cities to foster innovative solutions.

How to cite: Tong, X. and Wang, T.: Rethinking Future Travel Demand in China: Integrating IAM with Local Context for Sustainable Future Mobility, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-5507, https://doi.org/10.5194/egusphere-egu25-5507, 2025.

Large-scale wind power installations are expanding across the world as part of electricity decarbonization efforts. Extreme wind energy events including wind droughts can pose major challenges for decarbonizing electricity grids that increasingly depend on renewable, including wind, power generation. In the context of conversions of available potential to horizontal kinetic energy predominantly over oceanic regions that are often remote from wind farms as well as load centers, we simulate country and continental scale wind power generation across the world and examine factors driving wind droughts. We use ERA-5 reanalysis wind speed and a wind turbine power curve to estimate daily wind generation at existing sites across the world. Site-level generation is aggregated to estimate daily generation patterns at country and continental scales. We estimate wind drought patterns in absolute terms and with respect to anomalies in relation to daily climatology and examine associations between wind droughts and characteristics of the large-scale atmospheric circulation.

Long-range advection of horizontal kinetic energy can also play an important role in maintaining wind power, and we systematically explore and distinguish the roles of local and remote factors in driving wind power variability at three types of scales: site-level, country-scale, continental-scale. This study offers a systematic approach to comprehending interactions between the large-scale kinetic energy budget and wind power variability across scales. We investigate the following questions: What background conditions over open oceanic regions facilitate long-range advection of wind energy, and how critical is advection for wind power variability? What specific circulation regimes are more instrumental in driving overall variability? The results offer insights for understanding controls from the mechanical energy budget on decarbonizing energy systems, and factors driving their variability across timescales.

How to cite: Sahu, S., Gangopadhyay, A., and Seshadri, A. K.: A global investigation of atmospheric circulation regimes driving wind power generation and its extremes at country and continent scales, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7155, https://doi.org/10.5194/egusphere-egu25-7155, 2025.

A new wave energy atlas database for French Polynesia

A wave reanalysis was carried out over the whole French Polynesian ZEE, using Météo-France's MFWAM model at 0.05° resolution, derived from the WAM model with a spatial resolution of 5 km, a three-hourly step, and a temporal depth of 30 years. These results have been published on the ODATIS open data platform.

Compared with existing reanalysis, the islands are better modelled, and it leads to better estimates of wave conditions and propagation.

It has been applied to wave energy evaluation over the whole French Polynesia.

Simulating the integration of 10 MW wave energy in Tahiti: challenges and opportunities

Sea state data from the atlas were used as input for simulating the production of 10 MW wave energy through several systems. These simulations were carried out for integration into the Tahitian power grid at several injection points and considering existing and planned renewable energies plants.

Over the same past time period, the island's electricity mix was modelled, showing the complementarity of wave energy with the other renewable energies found on the island, in particular photovoltaics and hydropower.

Tahiti presents (as in 2022) an electrical mix of 64% Oil, 29% Hydro, 7% PV (including roofs and plants connected to the Grid). New PV plants + batteries are studied by local stakeholders for the next years, involving other types of issues (land & recycling).

Our work highlights the advantages and challenges of integrating wave energy into the grid and raises the question of the methodology's replicability on other islands.

How to cite: Dubois, C., Chabbert, H., Reveil, M., and Vitrac, V.:  Wave atlas of French Polynesia – Application on wave energy integration into the electrical mix , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-9146, https://doi.org/10.5194/egusphere-egu25-9146, 2025.

Abstract: A large strike-slip fault system has been found in the central Sichuan Basin, although its effects on the pre-Mesozoic tight dolomite gas reservoirs in the deep (>4500 m) subsurface are uncertain. By integrating 3D seismic fault mapping, detailed fracture characterization, and well production data, this study demonstrates that strike-slip faults are extensively developed as vertically stratified arrays within the Ediacaran, Cambrian, and Permian dolomite intervals. These faults connect Lower Cambrian source rocks to multiple reservoir horizons, thereby establishing both lateral and vertical hydrocarbon migration pathways. A defining element of this system is the spatiotemporal coupling of “source-fault-reservoir,” which underpins the formation of a large-scale, pre-Mesozoic fault-controlled gas accumulation. Seismic evidence shows that many of these faults exhibit near-vertical geometries, en echelon arrangements, and step-over structures, all of which foster intense fracturing in the adjacent dolomites. Such fracturing substantially enhances porosity and permeability, yielding localized “sweet spots” with improved storage capacity and fluid flow properties, particularly within slope areas where structural conditions favor gas trapping. Production data strongly corroborate the geological and seismic observations, with wells that intersect or closely adjoin these fault zones typically exhibiting higher flow rates and more stable production profiles. This phenomenon highlights the pivotal role of fault-induced fractures in reservoir performance and underscores the need for detailed fault mapping and fracture network analysis in deep, tight carbonate plays. Furthermore, the recognition of this large-scale, strike-slip fault-controlled dolomite reservoir in a deep intracratonic setting underscores its considerable exploitation potential and points to broader implications for petroleum geology. Consequently, this study provides a robust framework for understanding the interplay between fault architecture and reservoir quality, offering valuable insights for guiding future exploration and development in analogous deep carbonate basins worldwide.

Key words: Strike-slip fault; Deep tight dolomite reservoir; Strike-slip fault-related petroleum system; Migration and accumulation; Exploration; Sichuan Basin

How to cite: Tian, W., Jiang, T., and Wu, G.: Impact of Pre-Mesozoic Strike-Slip Faults on Dolomite Gas Reservoir in the Central Sichuan Basin and Its Exploration Potential, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-10984, https://doi.org/10.5194/egusphere-egu25-10984, 2025.

Land is not considered in its entirety in mitigation modelling, especially for India. Even when reported as an output, competing land demands from renewable energy (RE), urbanisation, agriculture, and forestry and the resultant trade-offs are not adequately captured in existing models. In this study, we augmented the Sustainable Alternative Futures for India (SAFARI) model to determine the feasibility of a net-zero transition from a land availability perspective. SAFARI is a system dynamics simulation model that captures the dynamic interactions among various land types and therefore their competition. Using SAFARI, we developed illustrative net-zero scenarios for India to understand the land implications of the transition. We find that while India might have just enough land at a national aggregate level to support the transition to net-zero emissions, local constraints and land conflicts owing to acquisition challenges are more likely to occur in a high electrification scenario where there is increased focus on RE. Alternatively, a scenario with a focus on use of alternative fuels, nuclear power, behavioural changes, and efficiency improvements in addition to electrification and RE, would be more inclusive and optimal for a country like India.

How to cite: Sundaresan, A., Ashok, K., Natarajan, R., Gangopadhyay, A., and Murthy, I. K.: Modelling land-use dynamics for net-zero emissions: a framework for informed decision-making in India, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-16313, https://doi.org/10.5194/egusphere-egu25-16313, 2025.

In the fields of geological research and engineering applications, fault identification is of great significance for understanding geological structure evolution, predicting geological disasters, and guiding resource exploration and development. Traditional fault identification methods based on manual interpretation and seismic attributes struggle to meet the requirements in terms of efficiency and accuracy when faced with complex geological conditions and massive amounts of data. With the development of deep learning technology, convolutional neural networks have demonstrated excellent performance in image recognition and segmentation tasks. However, the multi-scale characteristics of faults, that is, the fault structures in seismic images are diverse in size, shape, and complexity, pose severe challenges to image recognition. This paper innovatively proposes a fault identification method based on an improved U-Net neural network. Focusing on the multi-scale characteristics of faults, it aims to enhance the accuracy and robustness of fault identification. The model introduces a multi-scale feature fusion mechanism, skillfully integrating encoder feature maps with different spatial resolutions, which significantly improves the ability to express fault features. In addition, in view of the insufficient representativeness of synthetic datasets, this study adopts data augmentation techniques, performing operations such as rotation, flipping, and scaling on the training data to effectively expand data diversity and enhance the generalization ability of the model. Experimental results show that when the improved U-Net model is tested on the publicly available F3 seismic data of the Dutch North Sea and the data of an oilfield in the Junggar Basin, China, compared with the traditional U-Net model, it has achieved significant improvements in key evaluation indicators such as recognition accuracy, recall rate, IOU, and PR curve. Especially in complex geological backgrounds, the improved model can more accurately identify the location and shape of faults, providing a more reliable and efficient fault identification technical means for fields such as geological structure research, oil exploration, and underground engineering construction. It has important theoretical significance and practical application value.

How to cite: Huang, Y., Cui, L., Niu, Y., Tao, Y., Liu, Y., and Chen, Y.: 3D Fault Identification Based on Improved U-Net with Multi-Scale Feature Fusion, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-16619, https://doi.org/10.5194/egusphere-egu25-16619, 2025.

The success of Carbon Capture, Utilization, and Storage (CCUS) projects heavily depends on understanding subsurface fluid flow behaviour particularly through fracture networks. Fractures play a dual role in such operations: they can enhance reservoir injectivity and storage capacity by providing pathways for CO₂ injection, but they also pose risks by potentially compromising caprock integrity, increasing the risk of structural storage failure thereby enabling CO₂ leakage. Accurate fracture detection and characterization is essential for optimizing injection strategies, ensuring effective containment, and mitigating environmental risks. Fractures influence critical processes such as trapping mechanisms and pressure distribution within the reservoir. Furthermore, understanding their orientation and density is vital for designing safe and efficient CO₂ injection operations. These factors highlight the importance of robust, non-bias, automated, and scalable fracture detection methods. Traditional fracture identification methods rely heavily on manual interpretation, which is time-intensive, subjective, and challenging to scale for large fields with several wells. This study proposes a scalable automated methodology employing advanced deep-learning techniques to detect fractures from borehole imaging tools such as FMI, CMI, and ThruBit logs. The proposed approach uses detection transformers which eliminates the need for manual mask creation and post-processing steps by adopting an end-to-end framework, which not only identifies the presence of fractures but also estimates their orientation and density. Custom evaluation metrics were developed to measure the model's performance (in comparison with expert’s fracture analysis) in handling diverse geological and well conditions, including vertical and horizontal well orientations. The automated workflow facilitates speedy assessment of fracture networks which in turn can offer speedy actionable insights for CO₂ injection optimization, caprock stability assessment, and risk management. The model demonstrated an interpretation speed of less than one minute per 2 meters, with an ~80% F1 score (6 cm depth error margin), ~91% accuracy in dip picking (3° error margin), and ~93% accuracy in dip estimation (15° dip margin). By utilizing the proposed automated fracture detection model based on transformers, CCUS project planning and designing can be accelerated. Furthermore, integrating MLOps into the workflow ensures the scalability, maintainability, and adaptability of these models for practical deployment. While this methodology is tailored to CCUS, its versatility extends to a much wider range of applications, including geothermal energy, mining, and other subsurface characterization domains.

How to cite: Nasim, M. Q., Maiti, T., Mosavat, N., Grech, P. V., Singh, T., and Roy, P. N. S.: Automated end-to-end fracture identification, classification, localization, and parameter estimation for enabling rapid risk management and CO₂ storage optimization in CCUS applications, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-627, https://doi.org/10.5194/egusphere-egu25-627, 2025.

The Himalayan alpine treeline possesses a unique identity and plays a vital role in the ecosystem. This study explores the relationship between soil quality and the distribution, diversity, and regeneration patterns of tree species in the alpine treeline regions of Uttarakhand Himalaya. The research focuses on five different treeline sites in Uttarakhand: Dayara Bugyal, Tungnath, Valley of Flowers, Ali-Bedni Bugyal, and Khaliya Top. Tree diversity and regeneration sampling in the treeline region were conducted by laying out 0.01 hectares quadrats, which were selected using the belt transect method along the treeline and soil samples were collected from each quadrate at 0-15 and 15-30 cm soil depths. The Rhododendron campanulatum, Quercus semecarpifolia, Abies spectabilis and Betula utilis are predominant in the treeline region of Uttarakhand Himalaya. Analysis of tree regeneration indicates generally poor regeneration for most species, with specific site variations. The additive Soil Quality Index (SQI) ranged from 2.30 to 2.84, 2.35 to 2.84, and 2.32 to 2.84 at soil depths of 0–15 cm, 15–30 cm, and 0–30 cm, respectively. Similarly, the weighted SQI showed a comparable trend, with Ali-Bedni Bugyal recording the highest values (0.95–0.96 across all depths). The reported SQI values exhibited a positive correlation with soil physicochemical properties and a negative correlation with vegetation density at the seedling, sapling, and tree stages. The site-specific variations in tree species distribution, diversity, and soil quality reflect distinct ecological dynamics and species interactions, while the poor regeneration status of most tree species highlights the need for targeted conservation strategies.

How to cite: Kumar, S., Sati, S. P., and Khanduri, V. P.: Tree density, distribution and regeneration status in relation to soil quality at different alpine treeline regions of North-west Himalaya, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-1094, https://doi.org/10.5194/egusphere-egu25-1094, 2025.

Rare earth elements (REE) have become indispensable in a wide range of modern technologies, yet their potential environmental impacts in gold mining regions are poorly understood. In this study, we collected soil samples from various locations within gold mining areas and analysed their REE contents using Neutron Activation Analysis (NAA), a precise and non-destructive method. To evaluate contamination levels and potential ecological harm, the enrichment factor (EF), geoaccumulation index (Igeo), and ecological risk index were applied.

Results revealed varying degrees of REE enrichment across sampling sites, with elevated EF values ranging from 0.20 to 2.70 and PLI values between 0.27 and 1.16 indicating no enrichment. Specifically, Eu and Tb showed the slight enrichment factors, might indicating an anthropogenic influence. The ecological risk index further indicated that 12.5% of the sampling sites might pose moderate ecological risks.

Overall, these findings underscore the importance of systematic REE monitoring and risk assessment in gold mining regions. Integrating REE analyses into environmental management strategies can help mitigate potential ecological impacts, ensure sustainable resource utilisation, and preserve environmental quality in these mineral-rich landscapes.

How to cite: Ahmed, M. E., Abbo, M. A., and Bounouira, H.: Integrating Neutron Activation Analysis and Multi-Index Assessments to Evaluate Rare Earth Elements in Sudanese Gold Mining Areas, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2493, https://doi.org/10.5194/egusphere-egu25-2493, 2025.

In recent years, deep-seated hydrocarbon reservoirs have gradually become the focus of exploration and development. The distribution of deep-seated oil reservoirs in the southern part of the Panyu 4 depression in the Pearl River Mouth Basin shows the characteristics of more in the north and less in the south, and uneven in the east and west. The unclear causes of oil differentiation have constrained its exploration. This paper uses a combination of logging, seismic, and physical property data to analyze the reasons for oil enrichment differences from the perspectives of source-reservoir matching, dominant migration channels, and fault activity, and establishes an oil accumulation model.

Research findings indicate that: (1) Based on the matching relationship between hydrocarbon source rocks and reservoirs, the area can be divided three types of well areas: "near-source poor in sand", "near-source rich in sand", and "far-source rich in sand". The northern sand bodies close to the hydrocarbon source rocks and have a large scale, so the oil enrichment degree is relatively high. (2) The fault structure ridges are the preferred channels for lateral oil migration. The oil is more enriched in the well areas near the structure ridge, leading to differences in oil reservoir between adjacent well areas in the east-west direction. (3) The strength of fault activity controls the stratum of oil enrichment in different well areas. In the northern area, the fault activity is strong, and oil is distributed in multiple stratum. In the southern area, the fault activity is weak, and the oil is transported over long distances through the oil source fracture and the sand body of the Wenchang Formation to the high structural parts in the south, where they are trapped in the Wenchang Formation. (4) Based on the aforementioned research, two types of oil accumulation models were established: the "proximal fault multi-layer accumulation model" near the source and the "long-distance stepwise migration and accumulation model" far from the source, along the dominant migration channels. This study has significant guiding implications for the further exploration and development of the Panyu 4 depression oil reservoir.

Key words: Differential enrichment of oil; Source-reservoir matching; Dominant migration channel; Fault activity; Oil accumulation model.

How to cite: Wang, Q., Liu, H., Peng, G., and Long, Z.: The mechanism of differential enrichment of deep oil reservoirs in the southern part of the Panyu 4 depression in the Pearl River Mouth Basin, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3371, https://doi.org/10.5194/egusphere-egu25-3371, 2025.

Taiwan's Tatun Volcanic Group (TVG) is an active tectonic zone that moved from tectonic compression zones to crustal expansion. It is a graben, or region of crustal thinning structure, that is favorable to crustal magmatic intrusion. This geologic context supplies heat for the formation of geothermal and volcanic systems. In addition, TVG is a suitable location for geothermal exploration because of the numerous surface thermal characteristics associated with young volcanic rocks. By computing the geothermal radiative heat loss based on the land surface temperature (LST) obtained from thermal sensors on Earth-observing satellites, we can assess the geothermal resource reservoir of TVG. Firstly, the Stefan-Boltzmann law from the LSTs is used to derive the radiative heat flow (RHF). Second, the sum of the heat flux pixel values over the selected geothermal area is used to estimate the overall radiative heat loss (RHL). The background radiative heat loss is then computed, and by deducting the background radiative heat loss from the total radiative heat loss, geothermal (i.e., net) radiative heat loss is determined. The above process determines trends in geothermal radiative heat loss over time. The average value of the four-decade (1984 - 2024) trend of geothermal radiative heat loss at TVG is 211 MW, with an annual rate of increase of 1 MW (MegaWatt) each year. The mean value of heat loss estimation follows the same sequence as the traditional geochemical method used in earlier research. On the other hand, this study's annual growing rate estimation of TVG is noted for the first time. This study shows the advantages and benefits of employing long-term remote sensing datasets in geothermal and volcanic investigations. It is the first attempt to assess TVG's geothermal potential using satellite thermal observations. This application of remote sensing methods in TVG's geothermal investigation shows encouraging outcomes and can be applied to other geothermal systems across the globe.

How to cite: Chan, H.-P. and Chan, Y.-C.: Tatun Volcanic Group geothermal assessment: estimated radiative heat flux and heat loss from satellite thermal time-series datasets, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3869, https://doi.org/10.5194/egusphere-egu25-3869, 2025.

To safely store CO₂, it is necessary to accurately predict the behaviors and trapping evolution of CO₂ in saline aquifers. However, due to the heterogeneity of actual saline aquifers, the evolution of CO₂ plume and accompanying trapping are still unclear during and after injection. Although prior studies have highlighted the impact of capillary entry pressure heterogeneity on CO₂ plume and trapping, the role and influence of CO₂-induced geochemical reactions are still not fully understood. Therefore, the main objectives of this work are to study the evolution of CO₂ plume and storage under heterogeneous capillary entry pressure and geochemical reactions. To illustrate the evolution, a comprehensive CO₂ migration and storage model under heterogeneous capillary entry pressure and geochemical reactions is done to study CO₂ behavior in detail. The results showed that heterogeneous capillary entry pressure in the saline aquifer can hinder the upward migration of CO₂, causing it to redirect and increase its lateral volume. The geochemical reactions can reduce porosity by 10^-4 and permeability by 1 mD within 100 years and hinder CO₂ migration in all directions. The capillary entry pressure magnitude, its heterogeneity, and lateral correlation length are the main parameters affecting the evolution of CO₂ storage. Their increase can greatly limit CO₂ vertical migration rates and decrease dissolution and mineral trapping amount but may double local capillary trapping amount. In contrast, the increase in temperature and the ratio of vertical/horizontal permeability favors CO₂ vertical migration, dissolution, and mineral trapping amount. Therefore, to ensure the long-term safety of CO₂ storage, it is necessary to select a suitable heterogeneous reservoir.

How to cite: Cui, G., Hu, Z., Chen, X., Liu, Z., and Lian, Y.: Influence of capillary force heterogeneity and geochemical raction on CO2 flow and trapping, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4956, https://doi.org/10.5194/egusphere-egu25-4956, 2025.

The growing demand for copper, driven by its critical role in green energy technologies such as electric vehicles and renewable energy systems, underscores the need to identify new copper resources. The Aravalli-Delhi Mobile Belt (ADMB), a geologically complex terrain spanning Rajasthan, Haryana, Gujarat, and Delhi, represents significant potential for copper mineralization within its Archaean to Neoproterozoic sequences. In this study, we developed a high-resolution copper prospectivity map for the ADMB by leveraging advanced machine learning techniques and integrating diverse geoscientific datasets. Our methodology incorporated geological features (e.g., proximity to folds, faults, and lineaments), geophysical data (gravity and magnetic anomalies), and remote sensing inputs (SRTM and LANDSAT imagery). Comprehensive processing of potential field data included upward continuation to multiple heights (500 m, 1000 m, 2000 m, 5000 m, 7500 m, 10,000 m, 15,000 m, 25,000 m, and 40,000 m), followed by the computation of first- and second-order directional derivatives, resulting in a total of 154 predictive features. Known copper deposit locations (56 in total) across the ADMB were used as training points, with feature sampling creating the dataset for machine learning model training. We addressed the challenge of class imbalance posed by the limited number of known deposits, by employing synthetic data generation techniques, including Variational Autoencoder (VAE) and Synthetic Minority Oversampling Technique with Generative Adversarial Networks (SMOTE-GAN). Comparative analysis showed that SMOTE-GAN produced more realistic synthetic samples, significantly improving model performance. The enriched datasets were used to train supervised learning models, including Explainable Boosting Machine and Random Forest, optimized within a Positive-Unlabeled (PU) Bagging framework to classify unlabeled regions. Our trained model achieved a predictive accuracy of 95.75% on an unseen dataset. The resulting copper prospectivity map effectively delineates high-probability zones, with nearly all known deposits falling within regions predicted to have probabilities >0.7. Our maps highlight regions of high prospectivity for copper resources that currently lack known deposits, suggesting potential new exploration targets.This demonstrates the robustness of our integrated data approach and machine learning models in identifying unexplored copper-rich areas within the ADMB. Our study highlights the importance of integrating geoscientific data with synthetic data generation to address data scarcity in mineral exploration. The demonstrated scalability of this framework provides a robust solution for prospectivity mapping in other similar Archaean to Neoproterozoic terrains worldwide.

How to cite: Kumar, M., Singh, S. P., Singh, U., Sarkar, S., Goyal, T., Sukhbir, S., and Shirmard, H.: Advanced Copper Prospectivity Mapping in Northwestern India through Machine Learning and Multisource Data Integration, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-5044, https://doi.org/10.5194/egusphere-egu25-5044, 2025.

Metallic deposits such as W-Sn, Cu-Au, rare earth deposits, thus serving as a “giant granary” of metal mineral resources in China(Lü  et al.,2021). There are five large-scale metallogenic belts only in the east of South China, namely the Middle-Lower Yangtze River Metallogenic Belt (MLYMB), Qingzhou-Hangzhou Metallogenic Belt (QHMB), Nanling Metallogenic Belt (NLMB), Wuyishan Metallogenic Belt (WYSMB), and Xiangxi-E’xi Metallogenic Belt (XEMB).

The source zones of the mineral systems in major metallogenic belts in South China are reflected by the vertical structures of the lithosphere in this area. In MLYMB, the mineral systems of the Fe and Cu deposits have multi-level source zones. The initial-level source zone is the enriched mantle, which is formed owing to the thinning of the lithosphere and deformation caused by the fluids in the asthenosphere. In QHMB, the source zone of Cu deposits such as the Dexing deposit is the mantle, while the source zone of W deposits on the margin of the Moho uplift such as Zhuxi and Dahutang deposits is the remelted crust. As for QHMB, the W and Sn mineral systems originate from the crustal magma. In WYSMB, the diagenism and mineralization are mainly related to the interactions between materials in the crust and the mantle. The crust-derived materials form the deposits mainly containing W and rare earths, and mantle-derived materials form polymetallic deposits such as Cu and Au. As for XEMB, it consists mostly of metal deposits of the type of strata-bound sedimentation with the crust as the source zone, such as Sb, Pb, Zn, and Mn deposits.

The pathways of the mineral systems of the major metallogenic belts in South China are deep faults and block or terrane boundaries determined by edge detection of gravity anomalies, as well as density contrast boundaries obtained with the 3D density model. The metallogenic pathways of Fe and Cu deposits in MLYMB mainly include the Yangtze River deep fault in NE trending and Tongling-Taizhou fault in SE trending and its secondary faults. The eastern segment of QHMB is mainly controlled by the faults in northeast Jiangxi, the southern segment of QHMB and the NLMB are mainly under the control of the boundary faults of F1, and WYSMB is related to Zhenghe-Dapu fault and Heyuan-Shaowu fault.

 A 3D density and susceptibility model was obtained by 3D gravity and magnetic inversion. The distribution of different types of deposits was qualitatively reflected by different combination of density and susceptibility model, revealing the distribution of termination sites of different mineral systems in South China.Mineral systems in this area, providing indications for future ore-prospecting exploration in South China.

How to cite: Yan, J., Zhou, Q., Chen, C., and Tang, H.: The controlling factors of major metallogenic systems in south china based on gravity and magnetic analysis, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-10108, https://doi.org/10.5194/egusphere-egu25-10108, 2025.

The development of renewable energies and the sustainable utilisation of geo-resources is evident in the increasing interest in mine water utilisation. In the densely populated regions of former coal mining areas, flooded mine structures present a promising opportunity for seasonal heat storage called mine thermal energy storage MTES. In addition to the general risks associated with post-mining utilisation, it is essential to assess the potential hazards posed by contaminants that may be remobilised through this geotechnology. Hard coal naturally contains contaminants such as polycyclic aromatic hydrocarbons (PAHs) and NSO-heterocycles, which have been detected in mine water. The utilisation of coal mines as thermal energy storage facilities leads to significant heating of the mine water (up to 80°C), which can enhance the solubility and mobilisation of contaminants into the water. However, to date, no comprehensive understanding exists regarding the mobilisation potential of these contaminants from coal mines at varying temperatures.

In this contribution, we present initial systematic flow-through experiments using columns filled with different coal types at various temperatures demonstrating that contaminant mobilisation, after an initial first flush, is primarily dominated by diffusion processes at the phase interface. Differences in the mobilisation of PAHs between the various coal types and at various temperatures are discussed.

Using numerical simulations, we demonstrate that the compound concentrations grow exponentially over the runtime of the MTES system due to the growing mass of coal being thermally stimulated. High temperature storage can lead to a short production time until the regulatory limit for PAH is reached. Without regulatory action an MTES in coal mines might not be economically.  We highlight that depending on mine-specific factors countermeasures need to be installed to contain the potential risk to the economic feasibility of such a storage system.  A reduction of the pollutants trough remediation techniques might be possible to enhance the lifetime of the MTES system, if natural attenuation through micro-biological activity is not sufficient.

How to cite: Blaes, L., Licha, T., and Heinze, T.: Organic compounds pose a risk for thermal storage in abandoned coal mines, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-11945, https://doi.org/10.5194/egusphere-egu25-11945, 2025.

What is more frightening than an unexpected earthquake in the middle of the night for people and for buildings and especially heritage buildings whose response to the earthquake is unknown.
The country of Morocco, and more precisely the region of Al Haouz, more precisely the city of Marrakech named capital of culture of the Islamic world for the year 2024, by the Islamic World Educational, Scientific and Cultural Organization (ICESCO), experienced a serious earthquake of magnetitude M = 6.9 on September 8, 2023 at 22:11:2.2 UTC (23:11 Local), the most serious earthquake in the history of the country according to seismic stations.
The Koutoubia Mosque built in the 12th century was one monument among others that suffered this tremor.
In this article we will describe the location, the construction technique and the materials used in this monument and we will also go through in a non-exhaustive manner the damage caused by this earthquake on the Koutoubia Mosque whose architecture is part of Almohad art.

How to cite: Belhaj, S., Baba, K., Belhaj, O. E., and Nounah, A.: The built material architectural cultural heritage tested by the Al Haouz earthquake: Case of the Koutoubia Mosque in the city of Marrakech, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13397, https://doi.org/10.5194/egusphere-egu25-13397, 2025.

Soil diffuse CO₂ efflux and soil radon (²²²Rn) and thoron (²²⁰Rn) gases activities measurements may be useful geochemical indicators of subsurface volcano-hydrothermal processes in geographical areas where visible gas emissions are nearly absent. Both radon (²²²Rn) and thoron (²²⁰Rn) are radioactive isotopes derived from the natural decay of uranium (²³⁸U) and thorium (²³²Th) respectively, present in the mineralogical composition of rocks. The main difference between these two isotopes is their half-life time. While ²²²Rn presents a half-life of 3.8 days, ²²⁰Rn has a shorter half-life of 55 seconds. Therefore, high ²²²Rn surface activity is considered to be associated with deep magmatic sources of gas while high ²²⁰Rn activity is associated with shallow soil gas sources.

A total of 968 sampling sites in an area of 25 Km² have been considered as part of a detailed surface geochemical study at the central-western part of La Palma and southwards from the 2021 volcanic eruption lava flow of Tajogaite Volcano. Both diffuse soil CO₂ efflux and radon and thoron activities discrete measurements were executed during field surveys between 2023 and 2024.

The diffuse CO₂ efflux measurements were determined, based on the non-stationary static accumulation chamber technique, using CO₂ sensors contained in a portable flux-meter, and the radon and thoron activities were evaluated using a SARAD radon monitor connected to a stainless steel probe inserted at 40 cm depth. Soil gas samples were also collected and analyzed in the laboratory to obtain the chemical and carbon isotopic composition profile.

Data analysis and treatment showed CO₂ efflux values up to 106 g*m^-2/day, ²²²Rn values up to 27000 Bq/m³ and ²²²Rn/²²⁰Rn ratio up to a maximum of 49. Both ²²²Rn versus ²²²Rn/²²⁰Rn ratio plotted together enabled to identify areas with a higher contribution of deeper sourced gas,which might indicate potential zones of interest of geothermal resources.

Furthermore, spatial distribution maps of these variables showed that the main CO₂ and radon gases anomalies are located along the coastline of the studied area, coincident with anomalous magmatic-hydrothermal origin CO₂ diffuse degassing areas. The magmatic-hydrothermal CO₂ might have acted as a carrier gas controlling the migration and transport of the radon trace gas towards the surface.

In conclusion, surface geochemical surveys might be useful for geothermal resources exploration studies, providing a reasonable definition of potential geothermal system boundaries and permitting an efficient and cost-effective posterior subsurface exploration phase.

How to cite: Gironés, A., Pérez, N., Padrón, E., Melián, G. V., Asensio-Ramos, M., Hernández, P. A., Padilla, G. D., Di Nardo, D., Martín, A., Ramos, C., Taño, D., and Trujillo, L.: Detailed surface geothermal exploration by means of diffuse CO2 efflux, radon measurements and radon/thoron ratio in Jedey, La Palma, Canary Islands, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-15478, https://doi.org/10.5194/egusphere-egu25-15478, 2025.

Geothermal energy, driven largely by the push towards achieving net-zero emissions, has garnered increasing interest in the past decades for electricity generation. Geothermal-related activities, as any other activity for energy projects that utilise the subsurface, could induce subtle deformations on the near-surface. Tiltmeters is a technology capable to detect submillimetre ground deformations but can be significantly affected by ambient temperature variations. This effect can mask potential minute deformation signals. The effect of ambient temperature variations on tiltmeter recordings still lacks systematic understanding due to the absence of precise monitoring data and appropriate interpretation guidelines. In this study we analysed continuous tiltmeter recordings for a full year period and quantified the close correlation between the ambient temperature and ground displacement in both east-west (EW) and north-south (NS) directions. This close relationship has also been suggested by their wavelet coherence (WTC) results with only small time-lag observed. Overall, appropriate recognition of temperature-related ground motions can benefit the understanding of shallow crust and promote the establishment of baseline for future geothermal-related practices.

How to cite: Qiu, C. and Pytharouli, S.: Quantification of the Impact of temperature variation on tiltmeter recordings for ground deformation monitoring, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20467, https://doi.org/10.5194/egusphere-egu25-20467, 2025.

The use of earth in the building industry offers the opportunity to reuse soil whiles meeting the challenges of circular economy through soil reuse and low embodied energy. However, the lack of standardized criteria for soil classification, suitability and a comprehensive understanding of the interactions between soil properties and construction techniques remain a significant barrier to widespread adoption. This study aims to propose criteria for evaluating and optimizing soil classification and suitability in earthen construction through experimental analyses. For this, the study will use three different soils, sampled from three different regions in France. Straw- fibred and non-fibred cylindrical specimen will be prepared in laboratory using the cob and adobe techniques. The prepared specimens will be dried at 40 °C and conditioned in a climatic chamber at 20 °C and 50 % relative humidity. The variation in dry densities, and Unconfined Compressive Strength (UCS) of the cob and adobe specimens will be observed. The impact of soil properties and implementation parameters such as water content, mineralogical composition (calcite and dolomite content) on these variations will be analyzed. To underline the contribution of these parameters, a principal component analysis (PCA) will be conducted on all the results to identify the most dominant factors affecting mainly the dry densities and soil strength. Future work will study the microstructure evolution in the specimens using the Brunauer – Emmett – Teller (BET) and the Mercury Intrusion Porosimetry (MIP) tests. The mechanical behaviour and microstructure evolution will be combined into developing new criteria for soil suitability considering the implementation process parameters and soil properties for earth construction.

How to cite: Ansaa-Asare, R. J., Das, G., Hamard, E., Razakamanantsoa, A., Duc, M., Cazacliu, B., and Verron, L.: An approach to develop suitable criteria for cob and adobe techniques, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-21192, https://doi.org/10.5194/egusphere-egu25-21192, 2025.

In the project focused on CO₂-enhanced coalbed methane exploitation and geological storage, the seam network structure of coal seams serves as a conduit for gas migration, diffusion, displacement, and storage. The mechanical properties of these coal seams are intrinsically linked to the propagation and evolution of cracks. Prolonged exposure of coal seams to CO₂ adsorption environments inevitably alters their structure and mechanical properties. Consequently, experimental research has been conducted on the microstructure and mechanical properties of coal seams with potential for CO₂ geological storage in China. The results indicate that, under varying CO₂ adsorption pressures and durations: The relative contents of calcite, chlorite, and kaolinite in coal decrease, while the relative content of quartz increases significantly. Notably, the influence of supercritical CO₂ on mineral composition and relative content changes is the most pronounced. Long-term CO₂ adsorption accelerates mineral dissolution and ion exchange rates in coal, resulting in a rougher surface of coal mineral particles. Numerous secondary pores and fractures emerge and coalesce to form dissolution pits and grooves. Some mineral particle structures transition from intact to fragmented, severely weakening the skeleton particles and mineral bonding strength. Significant transformations occur in pores and fractures of different scales, with CO₂ adsorption causing a mutual transformation of mesopores and micropores in coal, albeit without altering the pore type. The uniaxial compressive strength, Brazilian splitting strength, and fracture toughness of coal exhibit a similar trend with increasing CO₂ pressure: an initial rapid decrease followed by a gradual, more gradual decrease. The mechanical strength/fracture toughness of coal samples with three different bedding types follows the order: Diverder type > Arrester type > Short transverse type. As CO₂ pressure increases, the destructive characteristics of coal transition from sudden instability to gradual instability, and then back to sudden instability. Under CO₂ adsorption, coal fracture trajectories can be classified into three types and 12 subtypes: single destruction, multi-source destruction, and fragmentation destruction trajectories. The interaction between CO₂ and coal alters the specific surface area, total pore volume, and uniformity of pore size distribution of coal, significantly impacting its composition. These microstructural changes underpin the macroscopic mechanical properties of coal, which in turn affect its mechanical properties and failure characteristics. The research findings have significant implications for evaluating the efficiency and stability of CO₂-enhanced coalbed methane mining and CO₂ geological storage.

How to cite: Feng, G., Xie, H., Wu, F., Xiao, M., Sun, Z., Liu, H., Jin, P., Wang, G., Meng, T., and Hu, Y.: Experimental study on the influence of CO2 adsorption on the mechanical properties of anisotropic coal, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-21370, https://doi.org/10.5194/egusphere-egu25-21370, 2025.

With the increasing urgency of global climate change and rising energy demand, carbon dioxide (CO2) geological storage has garnered significant attention as an effective method for mitigating greenhouse gas emissions. In the CO2 geological storage process, understanding the behavior of formation fluids is crucial to ensuring both the safety and long-term stability of storage. However, in actual storage operations, industrial CO2 emissions are rarely pure and typically contain a variety of impurity gases. As a result, CO2 must undergo purification prior to injection, a process that is not only time-consuming but also adds substantial costs. When considering the entire carbon capture and storage (CCS) chain, including capture, transportation, and purification, the total cost of operating current and future CCS projects can reach nearly one billion dollars. According to recent literature, the transportation and storage costs for CO2 can be as high as 45 USD per ton. In China, where cost sensitivity is especially high, these elevated expenses could significantly hinder the implementation of CO2 storage projects. Industrial CO2 emissions often contain not only CO2 but also other gases such as N2, O2, H2S, H2, and SO2. Direct injection of these gas mixtures into subsurface storage sites has the potential to reduce the overall cost of a CO2 geological storage project. However, the effects of impurity gases on storage mechanisms and long-term safety remain insufficiently understood and require further investigation. This study explores the response mechanisms of formation fluids in the context of non-pure CO2 geological storage, focusing on the influence of water-rock reactions, water-rock-gas interactions, permeability, solubility, and changes in the ionic composition of formation waters.

Keywords: water-rock reactions; impure CO₂; permeability; solubility; formation water ionic changes

How to cite: liu, S. and Peng, B.: Study on the response of formation fluid during geological storage of impure carbon dioxide, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-21409, https://doi.org/10.5194/egusphere-egu25-21409, 2025.

Background: Appropriate bioprocessing of lignocellulosic materials into ethanol could address the world’s insatiable appetite for energy while mitigating greenhouse gases. Bioethanol is an ideal gasoline extender and is widely used in many countries in blended form with gasoline at specific ratios to improve fuel characteristics and engine performance. Finding a suitable microbial agent for the efficient conversion of lignocellulose is still an active field of study. 

Objective: To enhance the bioethanol production with effective lignin degradation and utilization of pentose and hexose sugars in an economical way.  

Methods: Ryegrass (Lolium perenne L.) biomass was the substrate. Microbial strains Bacillus mobilis, Bacillus velezensis, and Bacillus cereus, were isolated, identified, determined for their lignin degradation capability, and used as pretreatment agents for the lignin degradation. Various modern spectroscopic analyses, ligninolytic activity, sugar estimation, enzymatic hydrolysis, and liquefaction and fermentation process were conducted. The final data was statistically validated with post-hoc Tukey test, R software and SPSS Statistics 26.

Results: The proximate and ultimate analyses of raw biomass showed that it comprised of total solids 96.54%, volatile solids 92.82%, carbon 48.22%, and sulphur 0.28%. After the application of bacterial pretreatments, the lignin content was considerably reduced to 6.78%, and the cellulose share increased to 57.31%. The LiP and MnP like activity was highest in alkaline lignin culture source with an amount of 0.67 ± 0.1 U/mL and 1.03 ± 0.08 U/mL, respectively. The optimum sugar utilization efficiency was reached at 93.46 %, with the highest bioethanol production of 0.51 g/g and 85.78 % bioethanol yield after the anaerobic fermentation.

Conclusion: In this study, successful delignification of the ryegrass biomass was achieved by bacterial pretreatments and maximum bioethanol was produced. The integration of bacterial pretreatments and C5 and C6 sugar utilizing microbial strains could enhance the commercial bioethanol production. The ryegrass biomass was selected since it is a common agricultural waste in China. The transformation of this biomass into industrial products like ethanol, would not only utilize waste but also accord to environmental safety. However, to meet global energy demand further studies to develop sustainable and cost-effective approaches are still required.

How to cite: Malik, K., Li, C., and Arshad, A.: Application of ligninolytic enzyme producing bacteria for enhanced bioconversion of ryegrass biomass into bioethanol, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-60, https://doi.org/10.5194/egusphere-egu25-60, 2025.

Seismic attributes contain a wealth of reservoir information, and the integration of various seismic attributes can enhance the accuracy of reservoir prediction. Due to the complex and heterogeneous underground geological structures, the suitable fusion algorithms vary not only among different oil fields but also at different locations or layers within the same oil field. Therefore, there is an urgent need to explore a multi-algorithm ensemble approach for attribute fusion to improve the generalization capability of seismic attribute integration methods. To improve the accuracy of reservoir prediction, an improved Stacking ensemble model-based method for predicting turbidite reservoirs has been proposed. Firstly, well log seismic attributes are optimized based on correlation analysis and unsupervised clustering techniques to construct a relationship model between seismic attributes and the thickness of turbidite reservoirs, reducing the ambiguity of seismic attributes. Then, hyperparameter optimization of the model is conducted using Optuna, and several types of models with good application effects and significant differences in the field of reservoir prediction are selected as the base learners of the Stacking ensemble model based on root mean square error (RMSE), mean absolute error (MAE), and correlation analysis. Finally, corresponding weights are assigned to the prediction results based on the test accuracy of the base learners, and the original dataset is also included in the meta-learner training, enabling the meta-learner to learn the implicit relationship between the original and new training sets, thereby enhancing the model's predictive performance. This method is applied to the prediction of turbidite reservoirs in the NZ Subsag, and the results show that compared with single prediction models and traditional Stacking ensemble models, the improved Stacking ensemble model significantly reduces the root mean square error in the prediction of turbidite reservoir thickness, and the correlation coefficient between the integrated attributes and sand thickness reaches 0.92, proving that the method has good application prospects.

How to cite: Zhang, S., Zhang, W., and Zhang, J.: The method of turbidite reservoir prediction based on improved Stacking ensemble model, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2170, https://doi.org/10.5194/egusphere-egu25-2170, 2025.

One of the key points of oil and gas exploration is the accurate description of reservoir thickness. However, due to the complexity of sand overlapping structure, the actual well earthquake relationship is poor, and the correlation between single seismic attribute and sand body thickness is weak, so the sand body thickness cannot be accurately predicted. In this paper, 8 kinds of seismic attribute information are extracted and selected, and the LightGBM model optimized by Newton-raphson-based optimizer (NRBO) is used to predict reservoir thickness with multiple attribute combination. It is found that the arc length, average amplitude, bandwidth, energy half an hour and other attributes of the selected working area are strongly correlated with the thickness. Meanwhile, the influence of the ratio of validation machine on the prediction results is studied. When the ratio of verification set is 20%, the best prediction effect is obtained, and the effect of the optimized model is significantly improved compared with the traditional machine learning methods such as LightGBM. The study of NRBO-LightGBM model in the prediction of sand body thickness has great popularization value and reference significance.

Newton-raphson-based optimizer (NRBO) is a new meta-heuristic optimization method, which is inspired by two key principles: Newton-Raphson search rule (NRSR) and trap avoidance operator (TAO). NRSR uses Newton-Raphson method to improve the exploration capability of NRBO and increase the convergence rate to achieve improved search space position. TAO helps NRBO avoid the local optimal trap. NRBO has the characteristics of strong evolutionary ability, fast search speed and strong optimization ability. This algorithm was proposed by Sowmya et al in 2024.

A large sample of machine learning reservoir thickness prediction research is carried out. Part of the data samples selected in this paper are actual samples, and part are thickness information predicted by SVM model. Fig.1 shows the prediction results when the proportion of test sets is 20%.

 Fig.1 Comparison of well point thickness prediction between NRBO-LightGBM and LightGBM

How to cite: Zhang, W., Zhang, S., Zhang, J., and Gui, Z.: Research on reservoir thickness prediction of river channel sandstone based on ensemble learning model, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2756, https://doi.org/10.5194/egusphere-egu25-2756, 2025.

Huizhou 26 sub-sag is rich in oil and gas resources. The oil and gas phases are complex and variable, with unknown origins. Based on the data of crude oil properties, well fluid components, and organic geochemistry, empirical statistical method and PVT phase diagram were used to identify the phase types in the study area. The spatial distribution characteristics and genesis mechanisms were analyzed. The results indicate that the crude oil from Huizhou 26 sub-sag has the characteristics of low density, low viscosity, low sulfur content, and high wax content. It also has three types of hydrocarbon phases: black oil, volatile oil, and condensate gas, among them black oil is the most widely distributed, volatile oil and condensate gas only distribute in the Huizhou 26-6 and 21-8 structural zones. Vertically, the phase types of Enping Formation are mainly volatile oil and condensate gas, while black oil, volatile oil, and condensate gas coexist in Wenchang Formation. Some wells exhibit a characteristic of vertical distribution of oil and gas alternation. The spatial differences of oil and gas phases are mainly controlled by the thermal evolution degree of source rocks and the filling process of oil and gas. Among them, the maturity of oil and gas corresponding to the main filling period and the proportion of late high maturity oil and gas mixing are the main reasons. Based on a comprehensive analysis of the formation stages and processes of different types reservoirs in the study area, three phase evolution models were established, namely "First stage oil phase filling", "Two stages oil phase superposition", and "Early oil phase, late gas phase". This study seeks to provide theoretical guidance for efficient exploration of deep hydrocarbons.

Keywords: Huizhou depression; oil and gas phases; condensate gas; differential filling of oil and gas

How to cite: Han, X., Liu, H., and Hou, M.: Characteristics and Genetic Mechanisms of Oil and Gas Phases in the Paleogene of Huizhou 26 Sub-sag in Huizhou Depression, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-5201, https://doi.org/10.5194/egusphere-egu25-5201, 2025.

For almost two decades, the Geological Survey of Canada has been working to understand the effects of geological resource development on the environment. This research is supported by the Environmental Geoscience Program. The goal of this program is to provide leading-edge scientific information to differentiate the effects of natural resource development on the environment from those of natural processes. The development of new geoscientific approaches serves to support the responsible development and use of Canada's natural resources through informed decision-making.

In this presentation, we will take a brief look back at key past activities and focus on the series of new projects that have just begun.

From 2019 to 2024, the program conducted some 15 projects in the following five themes: Baseline Characterization, Cumulative Effects, Deep Environments, Emerging Issues and Biosphere, Hydrosphere, Atmosphere. The range of projects included, among others, induced seismicity, oil sands, geological carbon sequestration and global mercury assessment with UNEP.

In its current phase (2024-2029), the program comprises a series of fourteen projects, divided into 4 themes: impact assessment, regional assessments, processes and characterization. Current projects include topics as varied as the national integration of groundwater knowledge, the use of clumped isotopes to characterize nuclear waste disposal sites, the study of metals in the environment of active metalliferous regions, or the study of aquifer contamination by legacy oil and gas wells on indigenous lands.

The vastness of the Canadian territory, combined with a resource-rich subsoil, provides the opportunity to carry out a multitude of geoenvironmental projects in support of sound environmental stewardship for the benefit of local communities.

How to cite: Cotteret, G. and Mochizuki, J.: Environmental geoscience research at the Geological Survey of Canada., EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7354, https://doi.org/10.5194/egusphere-egu25-7354, 2025.

The extensive use of petroleum-based plastics has led to severe environmental pollution, emphasizing the need for sustainable alternatives such as biodegradable polyhydroxybutyrate (PHB). Conventional PHB production using heterotrophic microorganisms requires external organic carbon sources, contributing to high production costs. Additionally, the separation of the biomass growth phase and the PHB accumulation phase in conventional systems limits production efficiency. This study introduces a dual-phase hybrid cultivation system designed to achieve simultaneous biomass growth and PHB accumulation in the cyanobacerium Synechococcus sp. The system alternates between a light phase that supports biomass growth via photosynthesis and a dark phase that promotes PHB synthesis. Synechococcus sp. was selected for its ability to fix CO2 as a carbon source, reducing the need for external organic carbon supplementation. To further enhance PHB accumulation, carbon by products extracted from cyanobacteria cell debris—including fatty acids, polysaccharides, and amino acids—were supplemented during cultivation. During the 14-day cultivation period, the hybrid system maintained biomass growth at a level similar to the conventional system. Meanwhile, PHB accumulation reached 7% (w/w DCW), over three times higher than the 2% in the conventional system. This demonstrates the system’s ability to enhance PHB synthesis without compromising biomass growth. carbon by products increased PHB production by approximately 40% compared to the conventional system without supplementation. This represents increases of 13% in PHB yield under non-supplemented conditions. These results indicate that the dual-phase hybrid cultivation system using internal carbon sources improves PHB production and offers a promising approach for bioplastics manufacturing.

How to cite: Shim, G.: Development of Dual Phase Hybrid Cultivation System to Enhance Polyhydroxybutyrate (PHB) Production by Synechococcus sp., EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7798, https://doi.org/10.5194/egusphere-egu25-7798, 2025.

This study explores a multi-objective optimization framework for energy retrofits, integrating future climate scenarios to evaluate their impact on economic, environmental, and human comfort objectives. As climate change is expected to alter temperature patterns, heating and cooling demands, and extreme weather conditions, conventional retrofit strategies may not be sufficient to maintain long-term building performance. Many existing retrofits rely on historical climate data, which may not accurately represent future energy needs. To address this, the study employs Representative Concentration Pathways (RCPs) and Shared Socioeconomic Pathways (SSPs) to generate future weather projections, ensuring a more forward-looking approach to retrofit assessment. The research utilizes EnergyPlus simulations, along with Honeybee/Ladybug, to model energy performance across various retrofit strategies. Multi-objective optimization, specifically NSGA-II (Non-Dominated Sorting Genetic Algorithm II), is applied to explore trade-offs between Life Cycle Cost (LCC), Life Cycle Carbon Emissions (LCCE), and occupant thermal comfort. The optimization process identifies Pareto-optimal solutions, balancing cost-effectiveness, energy efficiency, and indoor comfort. Retrofit measures considered include building envelope improvements, such as enhanced insulation, advanced glazing, improved airtightness, and cool roofs. The integration of cool roof technology is particularly relevant as it has the potential to reduce cooling loads, lower peak energy demand, and mitigate urban heat island effects, contributing to improved indoor comfort and reduced energy consumption. Preliminary findings suggest that climate-adaptive retrofit strategies, including cool roofs, could help improve energy performance and cost efficiency under changing climate conditions. The study provides insights for building designers, policymakers, and stakeholders, helping them develop more sustainable and resilient retrofit solutions. By integrating future climate data into retrofit planning, this research contributes to the long-term sustainability of buildings and supports efforts to reduce carbon emissions, optimize energy efficiency, and enhance occupant well-being. Future work could explore additional retrofit strategies, broader climate scenarios, and alternative optimization methods to further refine climate-adaptive retrofit planning.

How to cite: Le, T. D. and Lin, S.-Y.: Multi-Objective Optimization of Energy Retrofit Strategies under Future Climate Scenarios: Balancing Economic, Environmental, and Human Comfort Objectives, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7839, https://doi.org/10.5194/egusphere-egu25-7839, 2025.

The premise of porosity measurement with convention-al methods is to expose all the pores in the shale, which requires oil extraction to remove the retained oil in the shale. Shale oil reservoirs are characterized by oil-bearing, tight (low porosity and permeability), rich in organic matter, and clay swelling. The interactions between the solvents and shale minerals, organic matter, and pores have significant impacts on the pore system. Some researchers tried to evaluate porosity after removing all organic matter from the shale with solvents. Kuila et al.^[1] used sodium hypochlorite to extract organic matter from five shales. The results showed that the pore volume increased within certain pore size ranges and decreased within others, which could be attributed to the decrease of organic pores after extraction. Similarly, DiStefano et al.^[2] used solvent extraction to remove the organic matter from Eagle Ford shale samples. The results pointed out that the porosity did not always increase with the amount of extraction. This study used different organic solvents to conduct the solvent extraction on clay-rich and carbonate-rich shales. Nuclear magnetic resonance, nitrogen adsorption, and gas measurement were applied to reveal the changes of the solvent extraction efficiency, porosity, and the pore size distributions to investigate the impact of solvent extraction on shale pore system.

The samples used in this study were taken from the fourth member of the Shahejie Formation in the Jiyang Depression of the Bohai Bay Basin and the first member of the Qingshankou Formation in the Gulong Depression of the Songliao Basin.  Sample A is a carbonate-rich, low-maturity shale and Sample B is a clay-rich, high-maturity shale.

During the organic solvent extraction, the changes in shale pore systems may result from the combination of the following three mechanisms: (1) The removal of internal fluids (oil and water) and soluble organic matter in shale is the primary reason for the increase of shale pores. (2) During the organic solvent extraction, interactions between shale components and the organic solvents, including clay swelling, extraction of bitumen, and the dissolution of minerals, change in the original pore structure. (3) The kerogen would expand when contact with organic solvents, which will fill partial pores. The expansion coefficient depends on the maturity of the kerogen and the solubility of the organic solvent.

How to cite: Zhao, X. and Wang, M.: The impact of organic solvent oil extraction on shale pore system-Key Issues in Shale Pore Evaluation, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-8076, https://doi.org/10.5194/egusphere-egu25-8076, 2025.

Abstract: In tight reservoirs, fractures and pores play a crucial role in oil migration, accumulation, and production. However, there is a scarcity of research that concurrently examines both pores and fractures to understand their combined impact on the migration and enrichment of shale oil (tight oil). This study, guided by multidisciplinary theories such as petroleum geology, structural geology, and unconventional oil and gas accumulation theory, innovatively introduces the concept of "fracture-pore facies" and categorizes the reservoir fracture-pore facies into 20 distinct types. Through X-ray diffraction, the mineral content of the Lucaogou Formation reservoir was analyzed, and different mineral contents were observed. The fracture-pore coupling relationships in the reservoir were investigated through core observation, high-pressure mercury injection, cast thin sections, scanning electron microscopy, conventional logging, and image logging, identifying the types of fracture-pore facies in the study area. Physical simulation experiments were conducted to observe the migration and enrichment characteristics of oil in different fracture-pore facies. Based on experimental phenomena related to oil saturation, fracture opening, fracture density, permeability, porosity, and physical simulation of oil migration and accumulation, the fracture-pore facies in the study area were divided into three categories: the first category includes seamless-macropore facies and microfracture-medium-large pore facies; the second category includes multistage microfracture-mesopore facies and seamless-small mesoporous facies; the third category includes microfracture-micropore facies and seamless-micropore facies. Through the enrichment and accumulation models of different types of fracture-pore facies, combined with actual geological data from the study area, three oil enrichment patterns were summarized from the spatial perspective of different types of fracture-pore facies coupling: ① Seamless and medium-large pore coupling rich oil; ② Composite fracture-pore coupling rich oil mode; ③ Single microfracture-micropore coupling rich oil mode. The fracture network or fracture-pore network formed by the coupling of fractures with matrix pores in shale oil (tight oil) can significantly improve reservoir properties and control oil migration, enrichment, and exploitation. The types and classification of fracture-pore facies in shale oil (tight oil) provide important guidance for the study of shale oil (tight oil) migration, accumulation, and production.

How to cite: Zhang, Z. and Wang, M.: Fracture-pore facies types and enrichment models of shale oil (tight oil)- A case study of Lucaogou Formation in Jimusaer Sag, Junggar Basin, China, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-9068, https://doi.org/10.5194/egusphere-egu25-9068, 2025.

Achieving net-zero emissions and combating climate change necessitate the adoption of negative emission technologies. Direct Air Capture (DAC), which removes CO2 directly from ambient air, shows great promise but requires significant energy, particularly in the form of heat. Geothermal doublets are traditionally used to supply heat for district heating networks, which operate at lower temperatures than those required for DAC. This study explores integrating geothermal heat from a doublet with DAC using a heat pump, while repurposing waste heat from the DAC process to support district heating. We propose multiple operational configurations for this system and conduct a life cycle emissions analysis, demonstrating the potential to capture tens to hundreds of thousands of tonnes of CO2 over its lifetime. The results show that higher geothermal fluid temperatures and flow rates substantially lower the cost per tonne of CO2 captured. Conversely, higher fluid temperatures combined with lower flow rates reduce overall system costs. These findings highlight the critical role of optimal subsurface conditions in maximizing system efficiency.

How to cite: Miocic, J.: Linking geothermal district heating with Direct Air Capture, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12969, https://doi.org/10.5194/egusphere-egu25-12969, 2025.

Anaerobic digestion (AD) offers a sustainable solution for managing sugarcane vinasse, producing renewable energy and nutrient-rich effluents. However, the seasonal availability of vinasse (7–8 months annually) causes operational interruptions during the sugarcane off-season, undermining the stability and energy output of AD systems. This study addresses these limitations by evaluating glycerol as an alternative substrate during the sugarcane off-season in an anaerobic structured bed reactor (AnSTBR). The reactor was operated for 370 days at 30°C with polyurethane foam as support material. The system was inoculated with UASB granular sludge and transitioned between four operating stages: vinasse mono-digestion (V-moD), vinasse-glycerol co-digestion (VG-coD), glycerol mono-digestion (G-moD) and vinasse mono-digestion (V-moD), respectively. During Stage I, vinasse AmoD achieved 81.1 ± 1.5% COD removal at the highest organic loading rate (OLR) of 5.0 kg-COD m⁻3 d⁻1, with volumetric methane production (VMP) of 1027 NmL-CH4 L⁻1 d⁻1 and a methane yield (MY) of 250.6 ± 13.2 NmL-CH4 g⁻1-CODrem. Supplementing glycerol up to 50% (in terms of mass COD) in Stage II increased COD removal to 84.7 ± 1.1% and VMP to 1106.9 ± 70.2 NmL-CH4 L⁻1 d⁻1, though methane content declined by 5%. Glycerol AmoD (Stage III) yielded stable COD removal (93.1 ± 0.6%) and VMP (1075.1 ± 95.0 NmL-CH4 L⁻1 d⁻1), despite partial alkalinity reductions (881 to 253 mg-CaCO3 L⁻1) linked to higher metabolite accumulation (20 to 277 mg L⁻1). Returning to vinasse AmoD restored COD removal to 82.3 ± 0.6% with enhanced methane content (69.6 ± 0.6%) due to increased homoacetogenic activity. Substrate switching showed no significant impact (α = 0.05) on vinasse MY. Microbial analysis revealed shifts from Clostridium dominance during glycerol use to Bacteroides and Porphyromonas during vinasse digestion. Methanosaeta (47.6–74.2%) and Methanolinea (11.1–30.5%) dominated acetoclastic and hydrogenotrophic methanogenesis, respectively, supporting balanced acidogenesis-methanogenesis through acetogen-methanogen syntrophy

How to cite: Damianovic, M. H. R. Z., Takeda, P. Y., and Borges, A. D. V.: Glycerol Supplementation for Seasonal Stability in Anaerobic Digestion of Sugarcane Vinasse: Performance and Microbial Shifts, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13931, https://doi.org/10.5194/egusphere-egu25-13931, 2025.

This paper introduces HomeSHIFT, a framework designed to minimize personal energy carbon footprints through easily implementable algorithms for household energy management. HomeSHIFT leverages continuous monitoring of grid carbon intensity, which fluctuates based on the availability of renewable energy sources such as wind and solar. During periods of high wind and solar generation, grid CO₂ emissions are lower, while reliance on fossil fuels during other times results in higher emissions. Using grid carbon intensity data from CAISO and household energy data from utility smart meters, high-emission periods—particularly evening ramps—were identified.

HomeSHIFT optimizes battery discharge and EV charging schedules within the same time-of-use windows, aligning energy use with periods of lower grid intensity. The system operates seamlessly in the background, requiring no behavioral changes from the consumer, making it highly scalable and user-friendly. Under the Pacific Gas & Electric Time-of-Use tariff in Northern California, the high-price period runs from 4 PM to 10 PM on weekdays. Standard settings in the Tesla Powerwall application discharge the battery at maximum power starting at 4 PM, depleting it within two hours. Consequently, from 6 PM onward, the household must rely on grid electricity, often during peak carbon intensity. HomeSHIFT shifted the battery discharge to 7–9 PM, reducing grid carbon intensity by 46% compared to the 4–6 PM window. 

By prioritizing clean energy use and reducing consumption during high-intensity periods, HomeSHIFT offers a scalable and practical method for cutting household carbon emissions through small programming changes. These adjustments can be seamlessly integrated into existing applications without requiring consumer behavioral shifts. Scaling HomeSHIFT across all batteries, electric cars, and homes holds the potential to reduce millions of tons of emissions globally.

How to cite: Narayan, A.: HomeSHIFT: Automated Coordination of Home Distributed Energy Resources for Minimizing Personal Energy Carbon Footprint, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14204, https://doi.org/10.5194/egusphere-egu25-14204, 2025.

Development of methods of artificial intelligence in geophysics often require heavy computations using high-performance computing (HPC) with graphics processing units (GPUs). Given the ongoing energy crisis and exponentially growing demand for data storage and computational resources, the concept of Frugal AI has emerged recently. While there are attempts to use renewable energy for supplying data centres and HPC clusters, globally the energy supply remains being dominated by fossil fuels [1].

Frugal AI proposes to analyse and optimise the use of energy and water resources for data centres, computational power for data processing, AI model training and deployment for environmental sustainability of AI.

In support of the EU AI Act [2], there are significant efforts to develop standardisation documents for environmentally sustainable AI solutions (see draft technical reports ISO 20226 [3] and CEN/CENELEC 18145 [4]). The purpose of these standards is to offer AI stakeholders a practical approach to quantification of the environmental impact of AI solutions. In particular, carbon emissions of scopes 1,2,3 can be quantified with associated uncertainties. Scope 1 are direct emissions [5] which may occur in data centres that use reserve fossil-fuel generators (this is usually a temporary solution for autonomous power supply). Scope 2 are indirect emissions that are produced due to electricity consumption. It is possible to quantity such carbon emissions using a dynamic carbon factor based on real-time fuel mix in electricity generation, known power of used hardware modules (processors, memory modules, and GPUs), and duration of training and deployment of an AI solution. Scope 3 carbon emissions [6] are based on life-cycle assessment of an AI solution (“from cradle to grave”), which includes hardware manufacturing and software development and deployment.

It is not seldom that AI models are deployed in default non-optimised mode for trial-and-error experiments, which may take a lot of resources and produce a large carbon footprint. The output data of large-scale geophysical models augmented with AI may be stored in an inefficent way, which can be improved using good practices (in appropriate formats, suitable temporal and spatial resolution).

We will discuss various aspects of Frugal AI in geophysics and suggest what optimised techniques can be used at each stage of AI development for geophysical applications. Frugal AI development may include simpler algorithms that can achieve comparable results with significantly smaller energy consumption; refined processes of data gathering for capturing essential information for AI training (for example, sparse datasets); optimised designs of training models; and deployment of AI models for energy-saving technologies, such as Demand-Side Response (DSR). Further intervention may include use of energy-saving hardware units and analysis of AI life cycle, which would identify stages of AI use that require most resources, and how those can be reduced.

References

[1] World energy report 2023, https://www.energyinst.org/__data/assets/pdf_file/0006/1542714/684_EI_Stat_Review_V16_DIGITAL.pdf 

[2] The EU Artificial Intelligence Act, https://artificialintelligenceact.eu/

[3] ISO DTR 20226 Information technology --- Artificial intelligence --- Environmental sustainability aspects of AI systems.

[4] CEN/CENELEC DTR 18145 Environmentally Sustainable AI

[5] ISO 20181 Stationary source emissions. Quality assurance of automated measuring systems.

[6] ISO 5338 Information technology --- Artificial intelligence --- AI system life cycle processes.

How to cite: Livina, V. N.: Frugal AI in geophysics, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14712, https://doi.org/10.5194/egusphere-egu25-14712, 2025.

The requirement and push for decarbonising the global energy system are becoming increasingly critical. One area that has entered this conversation is the use of Micro and Pico scale energy solutions like flow-induced energy harvesters to utilise the untapped energy potential within pre-existing infrastructure, like the European water infrastructure where the unutilised energy potential is estimated at 10 TWh/y [1].  Understanding and assessing the overall application feasibility of these types of technologies is vital to the successful deployment and development of these Micro and Pico energy generation solutions. This assessment needs to include a feasibility assessment that integrates technical and economic feasibility alongside society acceptance, energy security, and environmental impacts of the devices in relation to the integration of current water and energy system infrastructure. Notably, a limited number of assessment tools carry out a comprehensive feasibility assessment of these technologies regarding their deployment as secondary energy generation technologies and integration of current water or energy systems.  

This research applies a comprehensive feasibility assessment tool which is being designed as part of the H-Hope Horizon Project (https://h-hope.eu) to assess the feasibility of one prototype design of H-Hope vortex-induced vibration energy harvesters (VIV-EH) in urban settings.

The results demonstrate that the current prototype design of the VIV-EH has a power output comparable to the energy generation output of other hydropower energy harvester (H-EH) devices. In that regard the prototype illustrates a positive technical feasibility regarding power generation. The assessment has defined factors such as device designs and manufacturing quality, as well as high water velocities and sediments in the water channels, as the most significant technical and operational risks of the VIV-EH. Furthermore, the current VIV-EH prototype cannot be considered economically feasible since LCOE is revealed to be up to 20 times higher in comparison with other H-EH prototypes and small-scale renewable energy technologies. On the other hand, the current design of the VIV-EH prototype presents a low ecological and environmental impact regarding material selection, manufacturing and installation in pre-existing water channels, and the assessment demonstrates that further optimisation to improve the efficiency of the VIV-EH prototype does further decrease the environmental impact per unit of energy produced by the device.

Overall, the results highlight that further development and optimisation of the VIV-EH will improve the device's ability to harness power potential in the system and enhance the device's resilience to mitigate the impact of the aforementioned risks. Therefore, it improves power output, reduces the LCOE and environmental effects of energy generation, and makes it more attractive for deployment and affordable as a secondary energy generation technology for off-grid and urban applications. This work showcases an assessment framework, which can potentially be applied to assess the feasibility of various types of micro or pico energy generation technologies as secondary energy sources to unlock unutilised energy sources in our modern infrastructure networks.

[1] Quaranta, E., Bódis, K., Kasiulis, E. et al. Is There a Residual and Hidden Potential for Small and Micro Hydropower in Europe? A Screening-Level Regional Assessment. Water Resour Manage 36, 1745–1762 (2022). https://doi.org/10.1007/s11269-022-03084-6

How to cite: Guðlaugsson, B., Marguerite Bronkema, B., Stepanovic, I., Secnik, M., Hočevar, M., and Christian Finger, D.: Unlocking Hidden Energy: Assessing Micro and Pico Solutions for Sustainable Power Generation in Water Infrastructure, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17847, https://doi.org/10.5194/egusphere-egu25-17847, 2025.

Waiwera is a small coastal village with a 50 °C warm geothermal reservoir of 400 metres thickness directly underneath [1-2]. Hydrogeological models support water management by providing insights into sustainable extraction of water from the reservoir. We analysed the system in several studies over the past decades, mainly the last ten years [3-12].

Geothermal waters at Waiwera originate from rainwater percolating downward and heating by the background geothermal gradient. The system is fed along a fault zone located at the base of the reservoir. New radiocarbon dating shows the upwelling water to be >20,000 years old [13]. The present contribution gives an overview of the current research status, as well as the ongoing reinterpretation of recharge models for meteoric water.

[1] Auckland Regional Water Board (1987): Waiwera thermal groundwater allocation and management plan 1986. - Auckland (NZ), Auckland Regional Water Board. 85 p. (AWRB technical publication; 39).

[2] Zemansky, G. (2005): Hydrogeological evaluation of the Waiwera geothermal aquifer. - Lower Hutt (NZ), Institute of Geological & Nuclear Science Limited. 56 p. Client Report 2005/131. Prepared for Waiwera Infinity Limited.

[3] Kühn, M., Stöfen, H. (2005): A reactive flow model of the geothermal reservoir Waiwera, New Zealand. - Hydrogeology Journal, 13, 4, 606-626. https://doi.org/10.1007/s10040-004-0377-6

[4] Kühn, M., Altmannsberger, C. (2016): Assessment of Data Driven and Process Based Water Management Tools for the Geothermal Reservoir Waiwera (New Zealand). - Energy Procedia, 97, 403-410. https://doi.org/10.1016/j.egypro.2016.10.034

[5] Kühn, M., Schöne, T. (2017): Multivariate regression model from water level and production rate time series for the geothermal reservoir Waiwera (New Zealand). - Energy Procedia, 125, 571-579. https://doi.org/10.1016/j.egypro.2017.08.196

[6] Kühn, M., Schöne, T. (2018): Investigation of the influence of earthquakes on the water level in the geothermal reservoir of Waiwera (New Zealand). - Advances in Geosciences, 45, 235-241. https://doi.org/10.5194/adgeo-45-235-2018

[7] Somogyvári, M., Kühn, M., Reich, S. (2019): Reservoir-scale transdimensional fracture network inversion. - Advances in Geosciences, 49, 207-214.
https://doi.org/10.5194/adgeo-49-207-2019

[8] Präg, M., Becker, I., Hilgers, C., Walter, T. R., Kühn, M. (2020): Thermal UAS survey of reactivated hot spring activity in Waiwera, New Zealand. - Advances in Geosciences, 54, 165-171. https://doi.org/10.5194/adgeo-54-165-2020

[9] Kühn, M., Grabow, L. (2021): Deconvolution well test analysis applied to a long-term data set of the Waiwera geothermal reservoir (New Zealand). - Advances in Geosciences, 56, 107-116. https://doi.org/10.5194/adgeo-56-107-2021

[10] Kühn, M., Präg, M., Becker, I., Hilgers, C., Grafe, A., Kempka, T. (2022): Geographic Information System (GIS) as a basis for the next generation of hydrogeological models to manage the geothermal area Waiwera (New Zealand). - Advances in Geosciences, 58, 31-39. https://doi.org/10.5194/adgeo-58-31-2022

[11] Kempka, T., Kühn, M. (2023): Numerical simulation of spatial temperature and salinity distribution in the Waiwera geothermal reservoir, New Zealand. - Grundwasser, 28, 243-254. https://doi.org/10.1007/s00767-023-00551-8

[12] Kühn, M., Stagpoole, V., Viskovic, G. P. D., Kempka, T. (2024): New data for a model update of the Waiwera geothermalreservoir in New Zealand. - Advances in Geosciences, 65, 1-7. https://doi.org/10.5194/adgeo-65-1-2024

[13] Viskovic, G. P. D., Stagpoole, V. M., Morgenstern, U. (2023): Results of microgravity survey and ground water sampling, Waiwera, Auckland. - GNS Science Report, 2023/33.

How to cite: Kühn, M., Schöne, T., Grabow, L., Viskovic, G. P. D., and Kempka, T.: Waiwera: evolving understanding of a New Zealand geothermal system, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-18360, https://doi.org/10.5194/egusphere-egu25-18360, 2025.

It is societal consensus that adequate and reliable supplies of affordable resources need to be obtained in environmentally sustainable ways [1]. The prevailing view in the scientific community is that large amounts of carbon dioxide (CO₂) from the atmosphere and highly radioactive waste must be disposed of safely - kept away from human habitat for a very long time. In that regard, studies on natural processes that extend over very long periods help to understand the long-term behaviour of deep geological repositories. You can't carry out experiments over thousands of years. However, processes similar to those that occur at depth can also be found in nature. In combination with short-term laboratory experiments and field tests, it is possible to provide a comprehensive and reliable picture of the situation and to give a prognosis on the long-term.

In the context of climate policy, the storage of CO₂ in deep geological formations is seen as a potential means to reduce anthropogenic greenhouse gas emissions and mitigate respective global warming effects. However, questions arise: is it feasible to store CO₂ safely without endangering humans or the environment? Science and technology did provide answers to this question. In this context the GFZ driven experimental pilot site at Ketzin demonstrated the safe and reliable injection of CO₂ into a saline aquifer on the research scale [1].

The search for a site for the disposal of highly radioactive waste is an intergenerational social and political task with a geoscientific core. The first challenge is to narrow down suitable areas. The second is to analyse the subsurface using geoscientific knowledge, methods and data to determine its suitability in detail. It is the famous search for needles in the haystack. In order to identify the site with the best possible safety the search has to be carried out systematic and specific [2].

The question to be answered is: how accurate, reliable and robust must be our knowledge for a decision where and how to dispose CO₂ or nuclear waste in the subsurface? Ultimately, it is necessary to clarify which data is needed in order to reduce the uncertainties of our conceptual thinking and ensure the development of repositories in practice.

[1] Kühn, M., Bruckman, V. J., Martens, S., Miocic, J., Stasi, G. (2024): Preface to the special issue of the Division Energy, Resources and the Environment at the EGU General Assembly 2023. - Advances in Geosciences, 62, 67-69. https://doi.org/10.5194/adgeo-62-67-2024

[2] Kühn, M., Kempka, T., Liebscher, A., Lüth, S., Martens, S., Schmidt-Hattenberger, C. (2011): Geologische CO₂-Speicherung am Pilotstandort in Ketzin - sicher und verlässlich. - System Erde, 1, 2, 44-51. https://doi.org/10.2312/GFZ.syserde.01.02.4

[3] Kühn, M., Heidbach, O., Heumann, A., Zens, J. (2021): Nadeln im Heuhaufen. - System Erde, 11, 2, 6-11. https://doi.org/10.48440/GFZ.syserde.11.02.1

How to cite: Kühn, M.: Copied from nature - locked up for eternity - storage of carbon dioxide and nuclear waste at depth, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-18801, https://doi.org/10.5194/egusphere-egu25-18801, 2025.

The rapid advancement of artificial intelligence (AI) technology is driving transformative changes across society. However, this progress also entails significant resource and energy demand, posing substantial new challenges to the Earth’s ecosystems. Specifically, the environmental impacts arising from AI model training and inference, data center operations, and the manufacturing and disposal of electronic devices threaten the balance of ecosystem material cycles and could exacerbate climate change. Therefore, it is urgently needed to understand the effects of generative AI technology growth on ecosystem material cycles and to identify sustainable AI technology development and application strategies. This study aims to quantitatively assess the resource consumption (including metals, plastics, and water), exergy use (primarily through electricity demand and fossil fuels), and greenhouse gas emissions associated with the anticipated growth of generative AI technology and its consequent impacts on ecosystem material cycles. First, we analyze resource and exergy use within the generative AI industry, encompassing AI model training and inference, data center operations, and the production of AI chips and devices. We quantify the consumption of key elements and water, alongside the exergy demand for electricity and fossil fuels. We employ a Life Cycle Assessment (LCA) methodology to evaluate the comprehensive environmental footprint of AI technology. Second, we examine the environmental impact of AI-related waste by evaluating the generation, treatment processes, and ecosystem effects of electronic waste (including AI chips, devices, and data center equipment). This analysis focuses on the environmental leakage pathways of hazardous and plastic waste and the patterns of material movement within the ecosystem, particularly with regards to soil and water pollution and biodiversity loss. Third, we model the impact of generative AI technology on key ecosystem material cycles, such as carbon, nitrogen, and phosphorus. We estimate changes in resource use, exergy consumption, and waste generation under multiple AI technology growth scenarios. Finally, we propose strategies for the sustainable development and application of AI technologies. Based on our findings, we will formulate concrete policy and technical recommendations for developing and implementing resource-efficient and low-exergy-consuming AI technologies.

How to cite: Park, H., Song, C., and Lee, W.-K.: A Study on the Impact of Generative Artificial Intelligence Growth on Ecosystem Material Cycles: Analyzing Resource Use, Exergy Use, and Greenhouse Gas Emissions, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-19301, https://doi.org/10.5194/egusphere-egu25-19301, 2025.

TETRA – the Toolbox and mEthodology for waTeR based AI projects

The development of modern and efficient tools for monitoring water resources is crucial for ensuring the sustainable availability of this essential resource, which is of great value to both humanity and the environment. Events like the fish die-off in the Oder River underscore the pressing need for improved river protection. The TETRA project aims to enable and accelerate the use of artificial intelligence (AI) in water management. Additionally, the bilateral collaboration of both German and French companies fosters the development of a shared European ecosystem for AI applications in the water sector.

The project’s goal is to develop and provide tools and methods that enable the successful implementation of AI projects in the field of water management. These will be made publicly accessible to both German and French stakeholders to facilitate and promote collaboration with a common toolkit and approach for AI projects. The evaluation of the tools and methods will be based on two use cases: monitoring the water quality of rivers and river restoration.

The TETRA methodology is based on the already available PAISE process model, which was specifically developed for the integration of AI methods into industrial processes and is being adapted for application in water management. Within the scope of PAISE, a toolbox with specific AI tools will be developed. Several applications will be utilized in this context.
The FROST server, provided by Fraunhofer IOSB, is an open-source implementation of the OGC SensorThingsAPI that manages and stores sensor data needed for analysis by AI algorithms. FROST will be extended to FROST-AI within the project to meet specific AI integration requirements. The developed algorithms will be integrated into PERMA, an open-source software developed by Fraunhofer IOSB that enables the management and parameterization of algorithms.
GLUON, a tool for creating and managing ontologies, enables the integration of expert knowledge into AI algorithms. If facilitates semantic search and knowledge modeling in water management.
Edge AI analysis employs technologies to analyze data directly on sensors (edge computing) to reduce latency and ensure data privacy.
Godot Search is a semantic search module that can be used to understand user queries through ontologies to find relevant information more efficiently, and will be improved throughout the project.
Case-Based Reasoning (CBR) for river restoration utilizes case studies and expert knowledge to improve restoration measures in water management.

The ontology, knowledge base, and data from the FROST server will be made available in collaboration with all partners in the TETRA Showcase via WebGenesis (IOSB) in a web portal for demonstration purposes. Through TETRA, a framework for the integration of the AI algorithms and standardized data storage will be created, forming a starting point for a shared ecosystem dedicated to AI-based water projects.

This research has received funding from the BMBF’s (Bundesministerium für Bildung und Forschung) directive on the funding of Franco-German projects on the topic of artificial intelligence, Federal Gazette of 20^th June 2022.

How to cite: Zenner, M., Hellmund, T., and Moßgraber, J.: TETRA – the Toolbox and mEthodology for waTeR based AI projects, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20110, https://doi.org/10.5194/egusphere-egu25-20110, 2025.

Shales, particularly lacustrine shales, are known to have undergone frequent changes during deposition and are highly sensitive to climate fluctuations, bioturbation, and other environmental factors. The mineral compositions, sedimentary structures, mixing patterns, and vertical sequences of shales exhibit high complexities and pronounced heterogeneities. The strong heterogeneity poses challenges in shale reservoir characterization. Previous studies have mostly examined variations in scale-specific shale parameters, often lacking integrated macro- and micro-scale analyses, while few have investigated the controls on shale heterogeneities across scales. One-dimensional XRD and XRF data from homogenized, pulverized samples may obscure valuable information with extraneous details, limiting the ability to capture shales’ intrinsic heterogeneities. In this study, we employed 2D micro-XRF imaging and SEM-AMICS (Automated Mineral Identification and Characterization System) scanning to characterize mesoscale mineral heterogeneities in lacustrine shales. Applying the box-counting principles and chemo-sedimentary facies analysis, we are able to identify representative elementary areas (REAs) at the mesoscale, which can be used to facilitate a more effective link between macroscopic and microscopic heterogeneities. Guided by the REA sizes and locations, we performed micro-drill sampling for low-temperature nitrogen adsorption and high-pressure mercury intrusion experiments, enabling effective characterization of pore structure heterogeneities and the determination of the influencing factors. Using mixed lacustrine shales from the Subei Basin, China, we evaluated the effects of depositional environments on heterogeneities and revealed the primary mineral factors that influence in situ pore structures. Our findings indicate that frequent changes in water depth and climate are major controls on the lamina formation in the Subei Basin mixed shales, thereby exacerbating shale heterogeneities. Clay minerals contribute strongly to micropore heterogeneities, while felsic and carbonate minerals predominantly influence the mesopore heterogeneities. Macropore heterogeneities are primarily controlled by felsic minerals. These insights advance our understanding on the primary factors influencing shale heterogeneities under complex, multifactorial conditions. Integrated across-scale information allows us to better inform shale reservoir characterization and development strategies.

How to cite: Guo, Z. and Liu, K.: Unraveling the Complexity of Lacustrine Shales via an integrated Macro- and Micro-Scale Characterization, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-108, https://doi.org/10.5194/egusphere-egu25-108, 2025.

In the development of tight oil reservoirs, wettability determines the distribution and flow behavior of oil and water during reservoir development and enhanced oil recovery. However, accurately assessing wettability is highly challenging due to the strong heterogeneity of the mineralogy and pore structures in tight sandstone reservoirs and the complex interactions between minerals and fluids. Traditional studies often focus on the average wettability evaluation at the macro scale; however, such local bulk wettability often overlooks the inherent micro- and nanoscale heterogeneities of tight oil reservoirs. They thus cannot properly represent the true wettability in highly heterogeneous and low-permeable tight sandstones. In this study we employed a multi-scale comprehensive approach to evaluate reservoir wettability of an Eocene tight sandstone reservoirs from the Bohai Bay Basin. An environmental scanning electron microscopy was firstly used to determine wettability at the pore scale through analyzing the condensation patterns of water vapor on pore walls. Contact angle measurements were then employed to quantitatively assess the mesoscopic wettability characteristics of tight sandstone surfaces. Finally, a combination of Nuclear Magnetic Resonance and spontaneous imbibition experiments were carried out to evaluate the distribution characteristics of oil and water across different pore sizes and determine the overall wettability of samples. We have found that significant fractional wettability and mixed wettability are present in the tight oil sandstones. Different minerals and various parts of individual minerals can exhibit distinct wettability characteristics. The fractional wettability of tight sandstone is primarily influenced by clay mineral types and morphology; grain-coating illite and grain-coating chlorite tend to show oil-wet characteristics, while dispersed sheet-like chlorite and rosette chlorite are more likely to be water-wet. The mixed wettability in tight sandstones is mainly controlled by pore sizes: for oil-wet samples, pores larger than 0.1 μm are generally oil-wet, while those smaller than 0.1 μm are predominantly water-wet. For water-wet samples, the pore-size threshold between oil-wet and water-wet pores is around 1 μm. The wettability of tight sandstone reservoirs in the study area is primarily controlled by pore sizes ranging from 0.1 μm to 1 μm. This finding provides critical pore size thresholds for accurately describing reservoir wettability characteristics and is essential for understanding and predicting fluid behavior within tight oil reservoirs. The integrated multi-scale method proposed here allows a more precise and reliable wettability assessment, offering a viable workflow for wettability evaluation of tight oil reservoirs.

How to cite: Chen, J. and Liu, K.: Scale-dependency Wettability of Tight Sandstone: Insights from an Eocene fluvial sandstone reservoir in the Bohai Bay Basin, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-109, https://doi.org/10.5194/egusphere-egu25-109, 2025.

The ever-expanding oil refining sector, a significant source of industrial emissions, is pursuing decarbonization aligned with the 1.5-degree climate change goal. Despite the discussion at national and global levels, the success of implementation hinges on technically and economically feasible mitigation action at individual plants. Here we develop a plant-level low-carbon pathway model for the oil refining industry by integrating the operating details of refineries (plant status, processing units, age, configuration, etc) and dynamic costs of low-carbon technologies. We find that global oil refining industry can achieve substantial decarbonization through carbon capture and storage technologies (CCS) and clean hydrogen production technologies, concentrated on deep conversion refineries. The large differences in the distribution of age and configuration of refineries across regions lead to heterogeneous decarbonization pathways. In China, 57.6%~58.6% of mitigation costs for deep conversion refineries are associated with decarbonization technologies on furnaces and boilers, especially oxy-combustion CCS, while in the United States, over 40% of mitigation costs for such refineries are linked to biomass gasification. Consequently, mitigation costs per ton of CO₂ for deep conversion refineries in the United States are only 68.6%~74.8% of those in China. Simultaneously shortening the retrofitting cycle and using bio-crude oil can further enhance cumulative mitigation by 52.6 Gigatonnes and achieve negative CO₂ emissions in the oil refining industry. Our results provide cost-effective insights into the diverse and feasible mitigation strategies of individual refineries and accelerate climate action.

How to cite: Ma, S., Meng, J., and Guan, D.: The plant-level decarbonization pathways and mitigation cost of global oil refineries, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-307, https://doi.org/10.5194/egusphere-egu25-307, 2025.

Tight reservoir wettability directly influences the flow and storage characteristics of fluids within pores, which is crucial for evaluating the mobility of oil and water during tight reservoir oil reservoir development, as well as analyzing the storage capacity of carbon dioxide and hydrogen in tight reservoir reservoirs. However, the low porosity and permeability of tight reservoir, coupled with its complex pore network structure, significantly increase the difficulty of wettability assessment. Traditional methods struggle to achieve accurate quantification of the volumes of pores with different wettability types in tight reservoir, relying more on qualitative or indirect evaluations. This study proposes a novel quantitative method for characterizing tight reservoir wettability types based on alternating spontaneous imbibition combined with nuclear magnetic resonance (NMR) fluid quantification. Through a series of alternating imbibition experiments—oil imbibition (SI-O), water imbibition (SI-W), secondary oil imbibition (SI-2O), and secondary water imbibition (SI-2W)—coupled with dynamic T2 and T1-T2 NMR monitoring, the changes in fluid content and distribution within tight reservoir pores during imbibition were elucidated. The results indicate that tight reservoir pores can be categorized into oil-wet, water-wet, and mixed-wet types, each exhibiting distinct pore size distribution characteristics. The SI-O and SI-W stages represent the fluid filling phase, during which tight reservoir pores are rapidly saturated with oil and water, respectively. In contrast, the SI-2O and SI-2W stages represent the fluid equilibrium replacement phase, where the total fluid content in the pores remains unchanged, and only the fluids in mixed-wet pores are replaced according to the imbibition fluid type. Based on the differences in tight reservoir pore wettability, an alternating imbibition model was developed and validated through T2 NMR analysis and fluid content changes. Using this model, the volumes of the three wettability types of pores were quantified, and their pore size distribution characteristics were further clarified through T2 projection spectrum analysis. Compared to traditional methods, this approach addresses the gap in quantifying and analyzing pore size distributions of different wettability types in tight reservoir, significantly improving the accuracy and reliability of tight reservoir wettability assessment. It provides a new perspective for wettability analysis and quantification in tight reservoir.

How to cite: Yu, C. and Wang, M.: Quantitative Characterization and Pore Size Distribution Analysis of Tight Reservoir Wettability Using Integrated Alternating Spontaneous Imbibition and Nuclear Magnetic Resonance Techniques, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4079, https://doi.org/10.5194/egusphere-egu25-4079, 2025.

The structure of coal bodies is the product of brittle or ductile deformation in coal reservoirs under tectonic stress, serving as a crucial parameter influencing pore distribution characteristics, permeability, adsorption-desorption capacity, and mine safety in coal reservoirs. It holds significant research importance for the exploration and development of coal resources and coalbed methane (CBM). Under stratigraphic temperature and pressure conditions, the chemical structure and physical properties of coal reservoirs undergo corresponding deformation and evolution, leading to changes in the stress field surrounding the coal reservoir, as well as alterations in coal rock strength, pore characteristics, adsorption-desorption capacity, and permeability. Seismic data encompasses various attributes such as amplitude, frequency, and phase, with distinct differences in rock physics attributes among different coal body structures, which are closely related to seismic attributes. Through multi-attribute analysis, seismic attributes associated with coal body structures can be extracted. Machine learning is capable of processing and interpreting the nonlinear relationships between vast amounts of seismic data and rock physics attributes. By establishing a coal body structure prediction model based on machine learning technology, the accuracy of coal body structure predictions can be enhanced, allowing for an understanding of the distribution characteristics of tectonic coal in the study area and providing a reference for CBM (methane) extraction, thereby effectively improving the efficiency of CBM (methane) mining.

How to cite: Wang, X., Tian, F., Sadik, A., Yuan, X., and Yang, Z.: Study on Coal Body Structure Prediction Method Based on Machine Learning and Multi-Attribute Seismic Data Integration, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4939, https://doi.org/10.5194/egusphere-egu25-4939, 2025.

Hydraulic fracturing or fracking for shale gas and oil production is a water intensive and environmentally damaging process. It is often blamed for groundwater contamination and artificial earthquakes. Therefore, cryogenic fracking using liquid nitrogen (LN₂) has recently emerged as much safer and greener alternative. This novel process enhances rock permeability by creating thermal fractures by subjecting hydrocarbon-bearing rocks to repeated freeze-thaw cycles. However, the extent and efficiency of this process depends on the constituent minerals of the rock. Clay minerals such as montmorillonite and kaolinite constitute on average approximately 30 to 35 % of shale. These phyllosilicate group of minerals, despite their common layered structures, vary in composition and arrangement, resulting in distinct properties. Therefore, total adsorption of LN₂ in the clay minerals of shale must combine insights on their individual adsorption responses. It is essential to estimate the total and residual LN₂ volumes trapped in pores that will impact the mobility of hydrocarbons. In this work, we studied adsorption behaviour of nitrogen inside the montmorillonite and kaolinite nanopores using Grand Canonical Monte Carlo (GCMC) simulations. The slit pores, with 5 nm, 8 nm, and 12 nm opening were simulated for reservoir pressures ranging from 50 to 95 MPa and temperatures from 300 to 355 K. The influence of pore size, composition, pressure, temperature, and fluid type were studied to understand the relationship between adsorption isotherms and excess properties. The Canonical Ensemble simulations were performed in conjunction with Widom’s insertion technique performed to estimate the average chemical potential and interaction among the N₂ molecules calculated via pair distribution function. The N₂ was precisely represented by TraPPE force field model. The simulated bulk phase densities of N₂ were observed to be in good agreement with literature values. As shown by the pair correlation function obtained from the Canonical Ensemble simulations, the bulk phase N₂ was in a supercritical thermodynamic state at rock-fluid equilibrium temperature and pressure. The results indicated that the pore volume on both surfaces played a crucial role in the behaviour of N₂ adsorption. It was observed that the adsorption capacity of N₂ was affected by the amount of available pore space, revealing insights into interactions between pore surface and adsorbed N₂. Additionally, the study also confirmed that the extent of adsorption was dependent on surface area and morphology of the material. The adsorption isotherms exhibited a well-defined relationship with excess properties of adsorbed N₂. Further, these simulations analysed the thermodynamic nature of adsorbed fluid within the pores using the molecular density distribution profiles across the height of the pore.

How to cite: Singh, A., Sengupta, A., and Guha Roy, D.: Adsorption Isotherms Analysis of Liquid Nitrogen inside Montmorillonite and Kaolinite Rock Pores using Molecular Simulations, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-5108, https://doi.org/10.5194/egusphere-egu25-5108, 2025.

The oil and gas extraction industry is at the forefront of today’s energy transition, balancing the need to meet global energy demands while addressing the urgent challenge of reducing greenhouse gas (GHG) emissions. There were 12,874 oil and gas fields in operation worldwide between 2010 and 2021, with a significant aggregation of large GHG emitters. The key drivers and characteristics of GHG emissions in the global oil and gas extraction industry (considering resource type, geolocation, and decision-makers) remain poorly understood, yet are crucial for identifying key emitters and supporting targeted emission reductions. Here, we developed a field-level time-series global inventory of GHG emissions from oil and gas production to evaluate the emission reduction potential of key contributors from 2010 to 2021. Our findings reveal that 55.9% of cumulative emissions are financed by investors from high-income countries, though since 2014, lower-income countries have increasingly self-funded their emissions. Just 20 fields (0.2% of all fields) are responsible for 21.2% of cumulative emissions, located primarily in the Middle East & North Africa and Other Europe & CIS regions. These key emitters, primarily backed by high-income investors, are characterized by aging infrastructure and high depletion ratios, contributing to high carbon intensities. Our results highlight the importance of tailored, field-specific measures—considering geolocation, resource type, field age, and terrain—to achieve substantial, targeted reductions in global oil and gas emissions.

How to cite: Lei, T. and Guan, D.: Greenhouse gas emissions from global oil and gas fields: Field-level inventory and analysis of key drivers, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-5240, https://doi.org/10.5194/egusphere-egu25-5240, 2025.

The Jeanne d’Arc Basin, within the Grand Banks of offshore Newfoundland and Labrador, Canada, holds prolific oil and gas fields and is currently being assessed for its CO₂ sequestration potential. Several factors, including the presence of existing infrastructure from conventional energy production, volume of available datasets, and favourable geologic conditions for storage, make the Jeanne d’Arc Basin and sequestration target areas in the basin attractive as CO₂ injection sites. We are assessing subsurface geologic conditions in areas of interest for CO₂ sequestration to determine the geologic risks and benefits of a variety of targets.

The target strata for CO₂ sequestration in this assessment are predominantly in post-rift sequences, sedimentary units that have not experienced complex extensional stress regimes and that mostly lack delineated vertical fluid flow pathways. However, a major consideration for targeting potential sequestration formations is understanding how sequestered fluids will behave and identifying possible migration pathways within and between the reservoir units. Understanding how the subsurface changes on a fine scale may become important for ongoing assessments, target ranking, and injection strategies. However, well data constraints are not distributed uniformly across the basin and seismic data are often too coarse to capture the fine details of the subsurface or are non-unique.

This presentation documents factors that we are considering for geologic assessment of the CO₂ storage potential in the Jeanne d’Arc Basin, such as changes in depositional regimes, fluid migration pathways (both vertical and horizontal), stress regimes and data quality/coverage. We also discuss the uncertainties and potential risk mitigation for storage targets.

How to cite: Waghorn, K., Welford, J. K., Sinclair, I., and James, L.: Assessing Geologic Uncertainty of CO2 Sequestration Targets in the Jeanne d’Arc Basin, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-5266, https://doi.org/10.5194/egusphere-egu25-5266, 2025.

The Sichuan Basin is a superimposed basin in southwestern China, primarily consisting of marine craton and foreland basin stages. Many sets of organic-rich shales have been deposited, enriching natural gas resources due to their high levels of thermal maturity. The Sichuan Basin has experienced multi periods of tectonic uplift event, accompanied with multiple hydrocarbon accumulation and phase transitions processes in the deep and ultra-deep reservoirs. The formation of paleo-oil reservoir plays an important role in the distribution of present-day gas fields, yet many records of early oil reservoirs have been destroyed. A series of methods including, petrography, cathodoluminescence, fluid inclusion, in-situ U-Pb geochronology, and basin modeling, were used to determine the multistage oil charge process in the Ediacaran Dengying Formation of the Weiyuan area, SW Sichuan Basin. The lace-like dolomite lamination and three stages of dolomite cement were petrographically, and geochronologically distinguished in the Dengying Formation, dated at c. 542 Ma, 486 ~ 482 Ma, 410 Ma, and 270 Ma, respectively. Three stages of bitumen in the Dengying reservoir indicated three episodes of oil charge. The first and second oil-charging events occurred at 500 ~ 486 Ma and 410 ~ 400 Ma, by combining the modeled timing of oil generation with mineral ages of the two generations before and after the solid bitumen. The modification of the Weiyuan paleo-oil pool occurred during the Caledonian tectonic uplift, after the second oil-charging event. The timing of the third oil charge was at 270 ~ 230 Ma, according to the Th value of aqueous inclusions coeval with secondary bitumen inclusions in the stage 3 dolomite cement (CD-3), close to the timing of main oil generation for the Lower Cambrian source rocks. The first oil charge may be a contribution from the Doushantuo source rock, and the Lower Cambrian source rocks provide the major contribution for the third oil charge. This research reveals the timing of multistage oil charging events in the southwest Sichuan basin, and provides a further method for determining the timing of oil charge in multi-cyclonic composite basins.

How to cite: Luo, T. and Guo, X.: Determination of multistage oil charge processes in the Ediacaran Dengying gas reservoirs of the southwestern Sichuan Basin, SW China, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-6758, https://doi.org/10.5194/egusphere-egu25-6758, 2025.

Fault seismic interpretation is a decision-making process that heavily relies on the choices of interpreters - it is a multi-solution problem. However, how do interpreters ground their decisions? To understand the foundations of interpreter decision-making, this works explores how newcomers develop competence in fault seismic interpretation. Building on the first author's journey of acquiring fault seismic interpretation skills during her PhD, this study highlights the interplay between individual and social factors in the development of subsurface interpretation expertise. Through a detailed analysis of the first author's journey, including stages of becoming a competent Petrel user, developing a reproducible workflow, and gaining insights into the uncertainties and biases in fault interpretation, this study examines how expertise evolves and how social interactions impact methodological choices.

The results presented in this work stem from the first author's PhD research, which covered learning to interpret faults using seismic images. The findings reveal how the author's interpretative choices aligned with established practices, informed by a thorough literature review and guidance from her supervisor. Initially, her interpretation of normal faults mirrored the simplified, planar structures commonly depicted in existing literature. This approach changed and the author acquired more consciousness about uncertainty and biases in seismic interpretation when returning to fieldwork and realising the inadequacy in interpreting normal faults with simple planar geometries. The inherently uncertain nature of the subsurface prevents the exclusion of potential interpretations, making its characterisation through seismic image interpretation a multi-solution problem rather than one with a single, definitive solution.

The insights gained from this analysis, particularly during the COVID-19 isolation period, underscore the importance of recognising and addressing biases and uncertainties in seismic interpretation. This study highlights the influence of social learning, the limitations of established practices, and the importance of considering multiple potential solutions. By understanding the human element in seismic interpretation, we can improve future training, workflows, and the overall reliability of subsurface models. By encouraging self-reflection among interpreters and advocating for a broader range of structural models, this work aims to enhance the field of subsurface studies response to the evolving demands of the Energy Transition Industry and improve the overall management of uncertainty and biases in seismic fault interpretation.

How to cite: Robledo Carvajal, F. F., Butler, R., and Bond, C.: Developing Competence in Fault Seismic Interpretation: A Personal Reflection, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-6879, https://doi.org/10.5194/egusphere-egu25-6879, 2025.

Accumulations of large volumes of CO2 related to mantle degassing, metamorphic reactions or magmatic processes have been found in many oil-gas bearing basins around the world . The Huangqiao area of the Lower Yangtze Plate hosts the largest CO2 gas field on mainland China. Throughout geological history, a significant influx of deep mantle-derived CO2 fluid occurred in this area. Understanding the timing of these CO2 charge and their effects on crude oil reservoirs is crucial for interpreting the distribution of present-day resources. The Cenozoic was long believed to be the only period during which CO2 charging occurred in the Huangqiao area, primarily because evidence of earlier CO2 fluid charges had been scarce. To address this, a comprehensive study utilizing petrography, cathodoluminescence, fluorescence and Raman spectrum of fluid inclusions, in-situ U-Pb dating, and basin modeling was conducted to elucidate the timing and interactions between crude oil and deep mantle-derived CO2 in the Permian Qixia Formation of the Huangqiao area. Three distinct phases of calcite veins were identified and dated: 251.7 ± 1.8 Ma, 124.16 ± 1.46 Ma, and 97.68 ± 1.20 Ma to 96.75 ± 0.25 Ma. The earliest CO2 charge, occurring around 251.7 ± 1.8 Ma, corresponds to a period when supercritical CO2 extracted low molecular-weight hydrocarbons from the S1g source rock. This timing aligns with the mass extinction event (251.4 ± 0.3 Ma), a rapid rise in atmospheric CO2 levels, and volcanic activity in the Permian Gufeng and Longtan Formations of the Lower Yangtze Plate, suggesting that the CO2 influx was volcanically driven. Between 124.16 ± 1.46 Ma and 96.75 ± 0.25 Ma, significant portions of the CO2 and crude oil within the Qixia Formation escaped due to tectonic uplift and erosion associated with the collision between the Yangtze Plate and the North China Plate. This research provides the first documentation of early mantle-derived CO2 fluid charges and their role in crude oil extraction from source rocks during transport from the mantle to the Earth's crust. Additionally, the study reconstructs the processes of CO2 and oil accumulation and leakage from the Indosinian to the Yanshanian periods, offering new insights into the evolution of hydrocarbon reservoirs in the Huangqiao area of Lower Yangtze Plate.

How to cite: Chen, J., Guo, X., and Huang, Y.: Calcite U-Pb dating and fluid inclusions reveal late Permian deep mantle CO2 fluid activity in the East China basin and its effect on crude oil within source rock: A case study from Huangqiao area of Lower Yangtze Plate, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7585, https://doi.org/10.5194/egusphere-egu25-7585, 2025.

Overpressure is a common feature in the Huangliu Formation of the Ledong Slope Zone, Yinggehai Basin, with pressure coefficients reaching up to 2.31. In this study, overpressure mechanisms in mudstone intervals of the Huangliu Formation (Upper Miocene) are investigated and their importance reconstructed in time. Acoustic and resistivity logs reveal characteristic responses to overpressure in mudstones, leading to its accurate prediction. As a result, this study shows that hydrocarbon generation is responsible for the recorded overpressures as proven by several lines of evidence. First, overpressured mudstones in the Huangliu Formation have anomalously high acoustic and low resistivity values. Low density values are not recorded suggesting that disequilibrium compaction is not responsible for the observed overpressure. A positive correlation is also lacking amongst vertical effective stress, acoustic velocity and density values - overpressured mudstones recording low effective stress and high density – a character indicating that overpressure is mainly caused by fluid expansion. Overpressured mudstones deviate from the normally loading curve and fall on the unloading curve. Secondly, overpressured mudstones are buried at depths above 3300-4300 m, and subjected to formation temperatures of 135-200℃. Corresponding vitrinite reflectance equivalents are 0.7%-1.3%, supporting that mudstones are in the oil generation window and generate large quantities of hydrocarbons. Overpressured reservoirs are also charged by gas/water mixtures and gas; overpressure among these reservoirs is attributed to pressure transfer during gas charge. Thirdly, the depth for transformation of clay types do not correlate with overpressure generation in the mudstones, suggesting that clay transformation is not the main mechanism promoting local overpressures. Models of maturity and hydrocarbon generation history for the study area show that the source rocks within the Huangliu Formation started to become overpressured at 3.5 Ma and that pore pressure is still increasing. Overpressure increased rapidly between 2.5 Ma and 1.0 Ma, and modelling results are consistent with the present-day values recorded on acoustic logs. For different types of inclusions, we established different paleo-pressure restoration model to quantitatively recover the trapping pressures of reservoir fluid inclusions. The reconstructed paleo-pressures for the four stages of natural gas charging are 29.5 – 41.5 MPa, 45.03 – 47.94 MPa, 35.0 – 100.7 MPa, and 97.22 – 104.31 MPa, with the paleo-pressure coefficients of 0.84 – 1.19, 1.31 – 1.39, 1.41 – 2.32, and 2.38 – 2.56, respectively. Quantitative models further indicate that the mudstones of interest can generate large quantities of hydrocarbons at present to maintain the recorded pore overpressures.

How to cite: Zhang, X. and Guo, X.: Mechanisms and evolution of overpressure for Miocene Huangliu Formation in the Ledong Slope Belt,Yinggehai Basin, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-8025, https://doi.org/10.5194/egusphere-egu25-8025, 2025.

Large-scale methane releases from geological hydrocarbon seepage and the dissociation of subseafloor gas hydrates under shallow waters are important drivers of atmospheric methane concentration increases and global warming. However, the processes, timescales, and fluxes involved in such emissions remain insufficiently constrained. In this study, we redeploy historic oil and gas industry datasets—including well logs, seismic data, as well as reservoir temperature and pressure data—to reveal reservoir-scale methane leakage, storage and release dynamics in the Håkjerringdjupet area at the offshore continental margin of Norway beneath the past Fennoscandian ice sheet during the last glacial maximum.

Our numerical approach considers glacial loading causing the overpressurization of a shallow gas reservoir, driving the expulsion of methane-rich fluids through faulted zones and into subglacial sediments. Glacially-driven pressure increments led to extensive methane hydrate formation within these sediments, storing carbon and significantly improving basal traction. Laboratory shear-strength measurements (Spangenberg et al., 2020), integrated with subglacial hydrate formation modelling (Li et al., 2022, 2023), indicate a minimum hydrate saturation to regulate glacial flow, with the subglacial hydrate system storing ~0.48 Gt of methane in Håkjerringdjupet. During deglaciation, we estimate that ~120–240 Tg of methane released by hydrate dissociation may have reached the atmosphere shortly after the last glacier retreated (about 16,000 years before the present).

Our findings highlight how legacy industry well data and conventional oil and gas technologies can be harnessed to advance understanding of subglacial carbon storage and fluid migration in response to climate change. Our work provides an insightful Pleistocene analogue for studying contemporary ice-sheet-driven methane storage and release, informing strategies for sustainable carbon management in the transition towards net zero emissions.

References:

Li, Z., Spangenberg, E., Schicks, J. M., and Kempka, T.: Numerical Simulation of Coastal Sub-Permafrost Gas Hydrate Formation in the Mackenzie Delta, Canadian Arctic, Energies, 15, 4986, https://doi.org/10.3390/en15144986, 2022.

Li, Z., Chabab, E., Spangenberg, E., Schicks, J. M., and Kempka, T.: Geologic controls on the genesis of the Arctic permafrost and sub-permafrost methane hydrate-bearing system in the Beaufort–Mackenzie Delta, Front. Earth Sci., 11, 1148765, https://doi.org/10.3389/feart.2023.1148765, 2023.

Spangenberg, E., Heeschen, K. U., Giese, R., and Schicks, J. M.: “Ester”—A new ring-shear-apparatus for hydrate-bearing sediments, Review of Scientific Instruments, 91, 064503, https://doi.org/10.1063/1.5138696, 2020.

How to cite: Li, Z. and Kempka, T.: Quantifying past subglacial methane storage and emissions under the Fennoscandian ice sheet by means of historic data from hydrocarbon industry, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-9227, https://doi.org/10.5194/egusphere-egu25-9227, 2025.

GEOMODELATOR is a Python-based Open Source software package for translation of static geologic models into regular structured simulation grids considering element partitioning by complex model geometries (Nakaten, 2024; Nakaten and Kempka, 2023). In view of the vast legacy data available from geologic and hydrocarbon exploration, it provides a basis for site-specific assessments of geologic subsurface utilisation in terms of risk assessments, as well as operational design and optimisation.

We have further developed the GEOMODELATOR software package to fit into a modular client-server based architecture for a more robust modelling workflow, which allows to transfer heavy computational workloads to dedicated servers providing adequate resources and memory. Consequently, models with high grid element counts can be developed on low-memory client systems like laptops. Furthermore, a Graphical User Interface (GUI) has been developed to allow modellers to implement static models and directly review the results without the need for data conversion for its visualisation in third-party software packages such as Paraview (Utkarsh, 2015).

The present contribution shows the application of GEOMODELATOR to generate a numerical grid for a simulation study on fluid flow and halite transport to account for potential impacts of geologic subsurface utilisation.

References:

Nakaten, B. (2024): GEOMODELATOR - A python library to generate simple structured 2d+ and 3d cell-based VTK models/files. V. 1.0. GFZ Data Services. https://doi.org/10.5880/GFZ.3.4.2024.003

Nakaten, B., Kempka, T. (2023): GEOMODELATOR – from static geologic models to structured grids for numerical simulations, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-2016, https://doi.org/10.5194/egusphere-egu23-2016

Utkarsh, A. (2015): The ParaView Guide: A Parallel Visualization Application, Kitware Inc., United States.

How to cite: Nakaten, B., Chabab, E., and Kempka, T.: GEOMODELATOR reloaded – now with GUI and client-server architecture, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-10442, https://doi.org/10.5194/egusphere-egu25-10442, 2025.

Urbanization and its associated energy demands are among the critical challenges of our time, emphasizing the need for innovative and sustainable strategies. A deep understanding of the energy performance of the building stock, particularly through the analysis of building age, is essential. Building age not only reflects insulation properties but also plays a central role in energy models that guide decision-making processes. However, the lack of data on this parameter remains a widespread obstacle.

This study aims to address this gap by developing a semi-automatic methodology that combines georeferencing and classification of historical maps to extract and analyze data on building characteristics. The city of Parma serves as a case study, where maps from the Italian Istituto Geografico Militare (IGM), often overlooked, are revitalized through digital tools to reveal historical urban transformations. Using GRASS GIS software, the proposed workflow segments and classifies cartographic data, filtering textual annotations, boundaries, and roads in order to isolate built structures and estimate their construction periods.

In this context, these maps offer a window into past urban landscapes, allowing us to trace their evolution and extract meaningful information about the energy characteristics of the building stock.

The proposed approach provides critical insights into urban energy systems by bridging historical and modern datasets, supporting the development of sustainable energy models. Through the application of multidisciplinary techniques, this research contributes to a deeper understanding of urban energy dynamics, aiming to address economic, environmental, and social challenges.

Keywords: Energy efficiency, Building stock, Building age, GRASS GIS, Historical maps, Cartographic classification, Multidisciplinary approach, Urban transformation

How to cite: Dalle Vedove, L., Dalle Nogare, G., Dalla Vecchia, C., and Vigato, T.: Mapping Building Age for Sustainable Urban Energy Systems: Georeferencing and Classifying IGM Maps with GRASS GIS, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-11770, https://doi.org/10.5194/egusphere-egu25-11770, 2025.

Geothermal energy has gained significant attention over the years as a renewable alternative to traditional fossil fuel energy systems. Non-producing oil and gas wells may be repurposed as geothermal wells for heating or electricity generation. Converting non-producing oil and gas wells into geothermal energy production can offset the costs of drilling new geothermal wells and provide an incentive for remediating non-producing well sites. However, the absence of regulations for geothermal well conversion in North America and Europe leaves many unresolved questions about the ownership and financial responsibility of the wells. Here, we present an analysis of non-producing well attributes, such as depth, location, type, and proximity to geothermal boreholes, and well integrity indicators, including methane emission measurements and surface casing vent flows, to identify suitable sites for geothermal energy conversion in the United States and Canada. We also explore various case studies of geothermal well conversion from around the world, comparing different geothermal systems and their applicability to Canada. The findings from this research will be useful in supporting policy development and regulatory frameworks for geothermal conversion projects in Canada, the United States, and around the world.

How to cite: Lamarche, B., Boutot, J., Prado, P., Zolfagharroshan, M., Vyriotes, D., Fogwill, A., Muehlenbachs, L., Sasmito, A., and Kang, M.: Converting Non-Producing Oil and Gas Wells for Geothermal Energy Production, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13332, https://doi.org/10.5194/egusphere-egu25-13332, 2025.

Time-lapse seismic monitoring of CO2 geological sequestration activities is a crucial process to ascertain continued containment and conformance of CO2 within the subsurface storage site. Time-lapse seismic monitoring produces a 3D image of the injected CO2 plume within the subsurface, helping to identify CO2 migration pathways and determine if and where leakage has occurred. Planning a time-lapse seismic campaign is a site-specific process that involves a multidisciplinary effort in building geological computational models, reservoir fluid flow simulations and time-lapse seismic modelling. It is a common workflow in oil and gas production activities and can be redeployed for CO2 geological sequestration. However, CO2 storage involves fluid physics processes that are more complex than most oil and gas conditions, which requires the use of specific physics models to properly predict fluid flow and seismic monitoring behaviour. These complexities are mainly related to the fact that CO2 is highly miscible in formation water, oil and hydrocarbon gas. For this reason, compositional fluid flow simulations must be used to model CO2 injection, rather than the simpler black-oil fluid models more commonly used for oil and gas production. Current commercial reservoir simulators are well capable of such complex simulations. However, this dissolution process must also be modelled in detail in the seismic modelling workflow, and this is largely neglected in time-lapse seismic feasibility studies. We first present a workflow for taking CO2 dissolution processes into account in time-lapse seismic modelling. Then we present a full time-lapse feasibility workflow applied to two different North Sea reservoirs, a saline aquifer and a depleted hydrocarbon gas reservoir. We show the importance of taking such detailed physics processes into account in these two different storage situations. As well as show the importance of time-lapse seismic feasibility studies for planning CO2 monitoring campaigns, in order to achieve the desired objectives and necessary requirements to verify CO2 containment and conformance.

How to cite: Côrte, G., Kopydlowska, B., Toh, S. Y., Landa, J., Pickup, G., Heidari, H., and MacBeth, C.: Time-lapse seismic feasibility studies for planning CO2 geological sequestration monitoring campaigns, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13505, https://doi.org/10.5194/egusphere-egu25-13505, 2025.

Natural gas as a viable alternative to reducing dependence on coal and oil in the process of energy restructuring and carbon neutrality goals. The efficient development of tight sandstone gas requires accurate evaluation of reservoir fracability and selection of layers and segments for fracturing. This study takes the tight sandstone in T area of Sichuan Basin, China as the research object. To achieve the fracturing goal of constructing a complex artificial fracture network, the key parameters affecting the comprehensive fracability of the reservoir are selected based on the fusion analysis of geological, logging, seismic, geomechanical, and microseismic monitoring information. In addition, the weights of each influencing factor are also clarified. The evaluation model of reservoir comprehensive fracability index and the grading evaluation standard of engineering sweet spot are constructed. Combined with geological framework, logging data, seismic attributes, and geomechanical 3D models, the longitudinal and spatial distribution characteristics of reservoir fracability and engineering sweet spot are analyzed. The research results show that high brittleness index, low horizontal minimum principal stress, high fracture density, low horizontal stress difference, low elastic modulus, and high Poisson's ratio are the key of "high sweetness value" of engineering sweet spot in the study area. The evaluation model of comprehensive fracability index (FI) of reservoir is established based on these six key indicators. The brittleness index, horizontal minimum principal stress, and fracture density are the three most critical factors identified by grey correlation method. The results of reservoir comprehensive fracability logging prediction and 3D comprehensive fracability field prediction show that the comprehensive fracability of the reservoir in the study area is non-uniform in the longitudinal, transverse, and spatial distribution, which can provide support for the selection of high fracability intervals and engineering sweet spots.

How to cite: Wan, Y., Liu, X., Liang, L., and Jing, R.: Fracability analysis and comprehensive evaluation of engineering sweet spot of tight sandstone gas reservoir in T area of Sichuan Basin, China, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13692, https://doi.org/10.5194/egusphere-egu25-13692, 2025.

Acid fracturing is a key technology in the development of fractured carbonate reservoirs, and the conductivity of acid-etched fractures is one of the critical indicators for evaluating the effectiveness of acid fracturing. However, current conductivity calculation models for acid-etched fractures primarily focus on single, regular fractures of small dimensions, which differ significantly from the morphology of real fractures. Moreover, calculation models for the conductivity of complex fractures are relatively scarce.

This study establishes a conductivity calculation model for complex acid-etched fractures based on large-scale acid fracturing physical model experiments, filling a research gap in the field of conductivity calculation models for complex fractures. The research first conducted large-scale physical model acid fracturing experiments (dimensions: 2m × 2m × 1m) and accurately obtained the etched morphology data of the generated complex fractures using three-dimensional laser scanning technology. Based on these data, the concept of contact ratio was introduced using linear elastic theory to calculate the deformation of acid-etched fracture surfaces under the influence of closure stress, determining the width distribution of the deformed fractures. Subsequently, a conductivity calculation model for complex fractures, accounting for natural fractures and multi-branch fractures, was constructed. Based on this model, the effects of various influencing factors on the conductivity of acid-etched fractures were systematically analyzed.

The study indicates that in complex fracture networks, fracture density, orientation, and length significantly influence conductivity. When the fracture density is high, the interconnectivity between fractures is greatly enhanced, forming an efficient flow network that substantially improves overall conductivity. Additionally, when the fracture orientation is parallel to the main fluid flow direction, the fractures provide the shortest and most unobstructed flow paths, achieving maximum conductivity. In contrast, when the fracture orientation is perpendicular to the flow direction, the contribution of the fractures to conductivity is significantly reduced, serving only a limited auxiliary role at fracture intersections or within the fracture diffusion range. Meanwhile, long fractures enhance overall reservoir conductivity by connecting more reservoir regions, whereas short fractures struggle to connect distant reservoir areas, resulting in poorer localized conductivity.

The complex fracture conductivity calculation model proposed in this study is more closely aligned with field conditions and holds significant value for the design and optimization of acid fracturing in reservoirs with well-developed natural fractures, addressing a critical gap in existing research.

How to cite: Zhang, L., Guo, X., Huang, Z., and Zhou, T.: Investigation on the Conductivity of Complex Acid-Etched Fractures Based on Large-Scale Mine Acid Fracturing experiments, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14711, https://doi.org/10.5194/egusphere-egu25-14711, 2025.

Fibrous veins are frequently observed in organic-rich shales in sedimentary basins worldwide. The formation mechanism of these fibrous veins remains a subject to debate. This study, based on core and microscopic observations, and employing techniques such as XRD, SEM, EPMA, fluid inclusions, stable isotopes, and rock pyrolysis, investigated the fibrous calcite veins in the Eocene of the Dongying Sag, Bohai Bay Basin, and analyzed the main controlling factors for their emplacement. The fibrous veins are bed-parallel, consisting of parallel aligned, fibrous calcite crystals. The median zone is composed of granular calcite containing wall-rock fragments and bitumen. The fluorescence colors of hydrocarbon inclusions in the fibrous veins are mainly orange-yellow, yellow, and yellow-green, with homogenization temperatures (Th) closely ranging from 74.5℃ to 86.4℃. The δ¹³C_VPDB values of the fibrous veins and the wall-rocks are between -2.37‰ and -5.02‰ and between -2.31‰ and -3.97‰ respectively, while the δ¹⁸O_VPDB values are between -9.59‰ and -11.56‰ and between -6.70‰ and -9.75‰. Our results suggest that the fibrous veins were formed through the combined effect of hydrocarbon-generation-induced overpressure and crystallization pressure. The hydrocarbon generation-induced overpressure drives the opening of the vein to form the middle zone. The fibrous crystals grow in an antitaxial direction from the middle zone towards the wall rock. They grow continuously driven by the chemical potential gradient as the vein forming materials diffuse and migrate from the wall rock to the vein surface.  Bedding, TOC, and mineral composition are the controlling factors for the formation and development of the fibers. fibrous veins are more likely to form in intervals dominated by carbonate minerals, with high TOC (＞2wt.%) and well-developed laminations.

How to cite: Li, T. and Meng, Q.: Calcite beef veins in oil shale, Bohai Bay Basin, China , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14855, https://doi.org/10.5194/egusphere-egu25-14855, 2025.

Based on PY-GC, Rock-Eval, TOC, burial history and thermal history data, the oil generating quantity can be calculated by chemical kinetic methods. The more oil is generated, the more oil is discharged, reflecting the stronger shale oil migration effect. Meanwhile, the in-situ oil content of shale increases, eventually reaching the upper limit of the reservoir and in dynamic equilibrium (Figure 1). And the content of non-polar and relatively low molecular weight saturated hydrocarbons in in-situ shale oil decreases (Figure 2). Based on chloroform asphalt A, group components, and pyrolysis data, the missing light and heavy hydrocarbons in experimental value S1 can be recovered to obtain the in-situ oil content of shale (Figure 3). From this, the hydrocarbon-expulsion efficiency (HEE) can be calculated. The research results indicate that, during the migration of shale oil, heavy isotope ¹³C with strong adsorption capacity is retained and enriched due to isotope fractionation, while light isotope ¹²C is more easily migrated and discharged. In order to eliminate the influence of kerogen type on carbon isotopes, the carbon isotopes of chloroform asphalt A, saturated hydrocarbons, aromatic hydrocarbons, non-hydrocarbons, and asphaltene were subtracted from the carbon isotopes of kerogen. It was found that the difference (Δ δ¹³C) between them increased with the increase of HEE, indicating that the stronger the migration effect, the heavier the carbon isotopes of chloroform asphalt A, saturated hydrocarbons, aromatic hydrocarbons, non-hydrocarbons, and asphaltene (Figure 4). Similarly, due to the geochromatography effect during the migration process, when the migration is strong, a large amount of tricyclic terpene with relatively low molecular weight will be discharged, and pentacyclic triterpene alkane will be relatively enriched, resulting in a decrease in the ratio of tricyclic terpene to pentacyclic triterpene alkane (RTP) (Figure 5). Non-polar and relatively low molecular weight saturated hydrocarbons are prone to migration, while non-hydrocarbons and asphaltenes have high relative molecular weight and contain a large number of heteroatom components, resulting in high adsorption and difficulty in migration. This leads to a decrease in the ratio of saturated hydrocarbons to aromatic hydrocarbons (RSA), as well as the ratio of saturated hydrocarbons and aromatic hydrocarbons to non-hydrocarbons and asphaltenes, as migration increases (Figure 6). The primary migration of crude oil within source rocks leads to differential enrichment of shale oil. The increase in HEE indicates a stronger migration of shale oil, leading to a decrease in the in-situ unit organic carbon oil content of shale and a decrease in shale oil saturation index (Figure 7). The light components with weak polarity and relatively low molecular weight in shale oil decrease with increasing migration, while the heavy components with relatively high polarity are relatively enriched, leading to a decrease in shale oil mobility.

How to cite: You, H. and Li, J.: Effects of Crude Oil Generation and Primary Migration on Shale Oil Enrichment and Mobility: A Case Study of Biyang Depression in the Nanxiang Basin, China, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-15167, https://doi.org/10.5194/egusphere-egu25-15167, 2025.

The decarbonization of communities and their energy supply is considered as a contemporary priority, although it poses many challenges. In this scenario, geothermal energy can cover a pivotal role in the energy transition and the possibility of reusing or modifying existing wells for geothermal purposes is becoming a hot and promising topic. In Italy for example, there are more than 4000 abandoned/inactive hydrocarbon wells, abandoned either for the end of the resource (exhausted well), or for the lack of finding the resource (barren well).These wells can represent a huge opportunity for geothermal resource exploration and exploitation, as historical well data can provide useful information on the underground conditions, reducing mining risk, and sometimes allow a direct access to the sub-surface heat energy.

This work aims to analyse the feasibility of retrofitting abandoned oil and gas wells to understand which the benefits of reusing old wells are compared to drilling new ones.

A finite element numerical model of a deep U-shape closed-loop Borehole Heat Exchanger (BHE) was implemented to evaluate the performance and efficiency in terms of energy production of this solution. Sensitivity analysis allows highlighting the main operational and environmental parameters involved in the heat exchange processes between the working fluid and the surrounding reservoir rocks, and particularly to quantify how the variation of design and geological parameters influences the outcome temperature of the working fluid and thus the energy efficiency and production of the BHE system.

After an initial round of simulations using purely conductive models, we investigated the potential for convective heat transfer within a geothermal reservoir, considering both porous and fractured media. Using the Nelson Diagram as a foundation, we assessed various permeability/porosity ratios to better understand how the interplay of these parameters influences system efficiency. Specifically, we explored whether fluid circulation within the reservoir enhances heat exchange over long-term simulations, potentially leading to improve system performance, particularly following extended periods of geothermal source exploitation.

How to cite: Facci, M., Di Sipio, E., Galgaro, A., and Bistacchi, A.: Reusing abandoned oil wells as deep closed-loop geothermal systems: FE multiparametric sensitivity analysis and the role of heat convection in fractured reservoirs , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-16643, https://doi.org/10.5194/egusphere-egu25-16643, 2025.

This study explores the concept of an innovative underground storage facility for liquefied natural gas (LNG), utilizing repurposed post-mining shafts. The design incorporates segmental cryogenic tanks, enabling safe and efficient storage of LNG in a structurally optimized environment. This facility also serves as a potential regional transshipment hub, supporting gas distribution to southern Poland and neighbouring countries, while leveraging existing mining infrastructure.

Key technical aspects of the design include the adaptation of abandoned shafts, the installation of reinforced concrete foundations to support substantial loads, and the placement of cryogenic tanks within self-supporting steel frames. The study addresses technical challenges such as shaft geometry constraints, geomechanical stability, and thermal management for cryogenic conditions.

The storage system offers significant capacity over 2000m³, with a single shaft section accommodating LNG volumes equivalent to dozens of transport tankers. This concept demonstrates the technical and economic benefits of reusing mining infrastructure, including reduced construction costs and maximized spatial efficiency. Moreover, it aligns with the principles of sustainable development and supports the just transition of post-mining regions.

How to cite: Kołodziej, K. and Lutyński, M.: Innovative Use of Mining Infrastructure: LNG Storage in Repurposed Shafts, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17869, https://doi.org/10.5194/egusphere-egu25-17869, 2025.

Veins featured by heterogeneous mineral components compared to the host rock are thought to give rise to the heterogeneous stress and strain during rock deformation, thereby impacting rock fracture behavior. To study the influence of veins on the mechanical and fracturing behavior of shale reservoir rocks, a series of triaxial compression tests were performed on different shale samples at room temperature and a constant confining pressure of 30 MPa. Samples contained either carbonate-rich veins or were vein-free. For the characterization of local strain within veins and host rock and the evolution of micro-fracturing during bulk sample deformation, we employed local strain gauge measurements, ultrasonic P-wave velocities, and acoustic emission monitoring. The peak stresses of bulk samples containing veins are generally lower, compared to their vein-free counterparts. For the samples with a vein, the spatiotemporal distribution of AE activity shows that fracturing was initiated in the vein, consistent with a pronounced decrease in the trace of P-wave velocity traveling through the vein. The final trajectory of fracture was either confined within or through the vein. We attributed this contrasting behavior to the varying vein geometry and the mechanical contrast of elastic moduli between the vein and host rock. This study underscores the role of veins in determining shale rock mechanical properties and fracturing behavior, which is important for the treatment of unconventional reservoirs and other relevant rock engineering projects.

How to cite: Chen, S., Wang, L., Rybacki, E., bonnelye, A., Wang, H., Zhou, T., Zeng, H., and Li, F.: Effects of veins on mechanical deformation and fracturing behavior of shale rocks under triaxial compression stress states: Insights from local strain measurements, P-wave velocities and acoustic emission activity, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-19466, https://doi.org/10.5194/egusphere-egu25-19466, 2025.

The ongoing structural transformation from the hydrocarbon industry to sustainable green energy is one of the challenges Europe is facing recently.In Germany, there are about 15,000 boreholes with depths ≥ 400 m (deep wells).Transgeo, a transnational project funded by the EU-program Interreg, aims to identify the potential of such boreholes for geothermal energy extraction in Germany and four other Central European countries.One of the main aspects of the project is the collection of data from deep wells, which will then be compiled into databases and fed into a web-based IT tool to demonstrate to potential investors the possible deep wells for geothermal energy extraction.The reuse of old boreholes, especially former oil or gas wells, is particularly attractive, as it can potentially reduce the costs of otherwise very costly geothermal drilling while making use of existing infrastructure.

The deep drillings in the eastern part of the North German Basin are mostly several decades old, as economic independence was sought especially during the GDR era and great efforts were put into the exploration and mapping of national raw material deposits. Hence, several comprehensive studies and data collections are still available in the archives. The value of analyses of taken samples, measured parameters, among other things is priceless. Such data is the basis for modelling, and also for the validation of existing models. Parameters here displayed, include temperature, porosity and permeability in identified pay zones within formations interesting for geothermal energy extraction. Also, the technical data about the borehole construction, as well as the detailed information about the location of cement bridges (abandoned wells), and geological or technical issues during, or after the drilling process are crucial, if considering a reuse or planning a new drilling project nearby an existing borehole. 

How to cite: Sieron, K., Weinert, S., Vogel, F., and Hoeding, T.: Re-evaluation of data from old deep boreholes with the aim of possible reuse for geothermal energy – advances in the TRANSGEO project, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-19652, https://doi.org/10.5194/egusphere-egu25-19652, 2025.

Geologically known for its ability to host significant oil and gas reserves in Northeast India, the Upper Assam Basin is a category-I petroliferous basin.  The study is aimed to utilise geothermal energy extraction of the Lakadong+Therria Formation in the Upper Assam Basin's depleted hydrocarbon wells.  The wells have recorded high bottomhole temperatures (BHTs) ~90 to 130 ̊C within the depth range of 3579 m to 4603 m. The feasibility of harnessing geothermal energy from these wells with high BHTs and correspondingly high geothermal gradient (>0.024 ̊C/Km) in the Lakadong+Therria Formation, is assessed in this work. The Monte-Carlo simulation study was performed to assess few wells with high heat flux in terms of stored Heat-in-Place (H.I.P), with the cumulative geothermal potential of 15.5*10^14 J.   The study would enable a comprehensive understanding to implement different geothermal energy extraction technologies to determine the viability of pilot-scale operations in the Upper Assam basin for electricity production or other greenhouse gas or district heating applications. This could start the energy transition pathway in the basin from fossil-based resources to low-carbon emission resources.

How to cite: Dutta, A. J., Mishra, C., Gogoi, N., and Kulkarni, S. D.: A Study on Geothermal Energy Production in Depleted Hydrocarbon wells of Upper Assam Basin India, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-21860, https://doi.org/10.5194/egusphere-egu25-21860, 2025.

One of the most critical challenges for preserving and protecting historical built heritage in coastal regions is the comprehension of the interaction between building materials and seawater or sea spray and its effects in time. This contribution addresses the forms and dynamics of sea salt weathering by considering as case study Mykonos Castle in Greece, built from the 13^th century and now surviving only in its towers, churches, and stone walls, being just a few meters away from the shore or even underwater. The fieldwork and preliminary laboratory activities were arranged for investigating the petrographic characteristics and decay patterns of the main building stones (gneisses, marbles, granitoids, etc.), their in-pore salt content constrained by orientation, height, and distance from the sea, and rate and amount of their surface erosion monitored on site. The findings are expected to help assessing the vulnerability of cultural heritage in coastal regions due to changing environmental stresses, also in view of climate change.

Acknowledgements

This study is carried out within the project THETIDA, which has received funding from the European Union's Horizon Europe scheme under the program Culture, Creativity and Inclusive Society (grant agreement no. 101095253).

How to cite: Germinario, L. and Mazzoli, C.: Salt weathering of coastal stone heritage in Mykonos, Greece, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2063, https://doi.org/10.5194/egusphere-egu25-2063, 2025.

Natural Hydraulic Lime (NHL) binders are generally preferred to those cement-based in case of restoration works, thanks to their good compatibility with historical substrates. Moreover, they can be considered more sustainable in comparison to cement, being sintered at lower temperatures. Nonetheless, while having a good compatibility with historic substrates, their performance might need improvement in terms of strength values and strength development without sensibly affecting their stiffness.
To this purpose, the incorporation of Graphene Oxide (GO) was considered, due to the beneficial effects showed by studies on cementitious binders. This work presents the characterization of NHL pastes (i.e. without aggregates) prepared with a water-to-binder ratio of 0.5 and 3 different dosages of GO retrieved from literature about cement and concrete, namely 0.01%, 0.06% and 0.12% by weight of NHL dry powder.
The NHL powder and the reacted binder were characterized via X-ray Powder Diffraction (XRD) and Scanning Electron Microscopy (SEM). From a mechanical standpoint, indirect tensile and compressive strengths were tested at 28 and 84 days of age, while stiffness was assessed via Ultrasonic Pulse Velocity (UPV) at 7, 14 and 28 days of age.
Preliminary results showed a minor strength improvement, which was more apparent at 84 days of age, with no remarkable modification of the stiffness. Results also indicates that it might be worth testing possible greater dosages of GO.

How to cite: Garbin, E., Panizza, M., Dalconi, M. C., Nodari, L., Costinas, C., Baia, L., Coteţ, L. C., and Tomasin, P.: An assessment of GO addition to an NHL binder, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3685, https://doi.org/10.5194/egusphere-egu25-3685, 2025.

The integrated studies within the field of non-invasive diagnostics for the characterization of the state of conservation of stone building materials of monuments have the common target to meet the current and future needs of society in the field of cultural heritage. The conservation of the built heritage requires many interventions aimed at analyzing the state of health of the monuments, their preventive preservation, reconstruction, and restoration. All actions and diagnostic analyses should respect the historical significance of the investigated monuments and the physical properties of the materials that make up the cultural heritage structures. In this context, the use of non-invasive diagnostic techniques of various nature (e.g. terrestrial laser scanner (TLS), digital photogrammetry, acoustic, electrical) plays a role of fundamental importance both in the preventive preservation and in the monitoring of monumental structures over time. In fact, the use of such techniques is also particularly effective in controlling the effectiveness of restoration interventions.

In this study we have examined different architectural elements (walls and semi-columns) of the Basilica of San Saturnino relevant monument in the historical centre of the town of Cagliari (Italy). The analysis has been carried out by different geomatic (TLS and digital photogrammetry) and geophysical (acoustics and electrical) techniques. The combined application of digital photogrammetry and terrestrial laser scanning can provide high-resolution 3D models calibrated and textured with both reflectance and natural colours useful for evaluating the state of conservation of surface materials and for rationally planning further geophysical analyses, particularly the acoustic ones carried out with tomographic methods. In this study the acoustic techniques applied in the ultrasonic range have been used essentially in two modes, namely: surface and transmission. The obtained 2D models adequately describe the longitudinal velocity distribution both on the shallow parts of the investigated old walls and on the internal section of different architectural elements (semi-columns) showing the influence of the variation of intrinsic rock properties on the ultrasonic longitudinal wave propagation. The electrical resistivity data acquired on the surface of the old walls have allowed to depict the resistivity distribution on the wall surface. Electrical resistivity is a physical property of a rock that characterizes its conductive properties. For porous media such as the building carbonate rocks under study, the electrical resistivity depends on many physical properties (i.e., internal structure, water content, fluid composition and porosity) and together with the elastic properties can be useful to interpret the various properties of the investigated materials and their conservation state. In conclusion, the non-invasive techniques applied in this study can effectively aid the restoration of the building materials at Basilica di San Saturnino, Cagliari, Italy. This study confirms how each technique gave a range of different information to the restorers, and the interventions that can be undertaken in light of the acquired knowledge of the investigated monument.

Acknowledgements: The authors would like to thank the Ministero della Cultura- DIREZIONE GENERALE MUSEI - DIREZIONE REGIONALE MUSEI SARDEGNA (ITALY) for their kind permission to work on the San Saturnino Basilica (Cagliari – Italy).

How to cite: Casula, G., Fais, S., Bianchi, M. G., and Ligas, P.: A multi-analytical approach to assess potential damaged areas on the building materials of monumental structures., EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4351, https://doi.org/10.5194/egusphere-egu25-4351, 2025.

The lithological nature of the bedrock helps explain this differential erosion, the position of the station being on a loose area while a few hundred meters further south, the construction on the base of the Pointe-aux-Oies would have allowed the building to be protected from erosion.

How to cite: Schmitt, F. G., Gaullier, V., Blaise, E., and Cohen, O.:  The fight against shoreline erosion along the coast of the second marine station of Wimereux (France), 1899-1942, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-8054, https://doi.org/10.5194/egusphere-egu25-8054, 2025.

Black crusts commonly form on historic buildings as a result of interactions between building materials and atmospheric pollutants. These crusts primarily consist of gypsum layers that develop on calcium-rich surfaces through sulfation processes, especially in urban environments with elevated atmospheric contaminants. Moreover, black crusts accumulate particulate matter, polyaromatic hydrocarbons, and heavy metals such as lead (Pb), largely originating from anthropogenic activities like vehicular emissions, coal combustion, and industrial operations. Acting as passive environmental samplers, these crusts offer valuable insight into urban pollution trends.

Although the water-soluble components of black crusts, such as Ca²⁺, Mg²⁺, Na⁺, and SO₄²⁻, have been extensively studied, the understanding of trace elements, particularly Pb, remains incomplete, especially regarding their behavior and mobility. This study aims to fill this gap by examining Pb distribution, availability, and interactions within black crusts and the underlying stone substrates. Samples collected from historical buildings in Antwerp were analyzed using a multi-technique approach. SEM-EDX was employed for initial chemical and morphological characterization, while LA-ICP-TOF-MS enabled the generation of high-resolution quantitative elemental distribution maps for major, minor, and trace elements. Depth-resolved analysis of Pb migration was further explored through portable LIBS, contributing to a deeper understanding of crust stratigraphy and pollutant dynamics.

Preliminary findings indicate that Pb is predominantly concentrated in the outermost layers of the black crust. Given the crust’s primary composition of gypsum, a sulfate mineral, it is hypothesized that Pb is sequestered as lead sulfates, contributing to its immobilization within the crust. However, this contrasts with existing literature, which highlights Pb’s stronger affinity for carbonate phases, suggesting a tendency for it to migrate into carbonate layers and potentially into the underlying stone substrate. The confinement of Pb within the crust deviates from expected behavior, raising important questions about its speciation. Understanding the conditions under which Pb could become mobile is crucial, with factors such as kinetic limitations, local pH variations, and environmental conditions like humidity and wet-dry cycles likely influencing its migration.

This research investigates the behavior of Pb within black crusts, aiming to advance the conservation of historic buildings while addressing the public health risks associated with urban lead exposure. By examining the factors influencing Pb mobility, the study seeks to inform the development of targeted mitigation strategies for lead contamination. The expected outcomes will not only contribute to the long-term preservation of cultural heritage but also enhance urban environmental safety, providing critical insights that bridge the fields of heritage conservation and public health.

How to cite: Deboli, S., Baele, J.-M., Bonazza, A., Van Acker, T., Vanhaecke, F., Wilhelm, K., and De Kock, T.: Lead Dynamics in Black Crusts: Elemental Distribution and Mobility Analysis in Lede Stone from Antwerp, Belgium, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-8233, https://doi.org/10.5194/egusphere-egu25-8233, 2025.

Integrating vertical greening systems (VGS) into historic buildings presents both advantages and challenges related to heritage conservation and urban sustainability. VGS contribute environmental benefits, such as reducing surface temperatures, improving air quality, and supporting biodiversity. However, their implementation raises concerns about potential risks to architectural integrity and cultural heritage.

This study explores expert perspectives on the implementation of VGS in historic buildings, focusing on the environmental, cultural, social, economic, legal, and technical aspects. Using a mixed-methods approach, the research combines insights from a literature review with survey data gathered from experts in vertical greening and heritage conservation. Both open-ended and closed-ended responses were analyzed to identify variations in expert opinions.

The findings reveal a general recognition of the environmental benefits of VGS; however, significant technical and cultural concerns present obstacles to widespread adoption. The results emphasize the need for increased awareness and structured information for stakeholders to promote a balanced approach that maximizes the advantages of VGS while addressing the challenges associated with historic architecture.

How to cite: Kale, E., De Groeve, M., Erkan, Y., and De Kock, T.: Expert Insights on Integrating Vertical Greening Systems into Historic Buildings: Survey Findings, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-9102, https://doi.org/10.5194/egusphere-egu25-9102, 2025.

Moisture has an important and essential role in the transportation of salts in masonry structures, therefore understanding the changes in moisture content provides valuable insights into the diagnostics of historic buildings, namely allowing the prediction of salt weathering. In this study, the thick walls of a fortress were studied. The Citadella is a landmark historic building in Budapest, that was built from Miocene porous limestone in the middle of the 19th century. Besides external cladding with porous limestone, the cores of the walls also contain volcanic tuffs. The walls are high (12-16 m) and their thickness is more than 1.5 m, which makes it difficult to record the moisture distribution. The sources of water are partly linked to direct precipitation on the wall surface or from capillary rise from pavement surfaces and from the soil. To assess the moisture distribution and salt content both on-site and laboratory analyses were performed during the dry summer period and wet autumn period. Not only the wall surfaces but also the subsurface zones and wall interiors were studied. Dry drillings were made to assess the in-depth moisture profile and salt content. Using an on-site moisture test it was possible to identify the moist and water-saturated zones of the ashlars and renders. Salt content and composition were measured on drilled dust samples and small samples obtained from the wall surface. Optical microscopy, XRF and XRD and Thermogravimetric analyses allowed the identification of salts. According to laboratory tests, the major salts responsible for the damage of external walls are gypsum, halite and hygroscopic nitric salts. The salt distribution within the depth shows seasonal variations. It was possible to detect the moisture distribution and salt content changes in depth and along vertical profiles. The results of the current research can be used to understand the moisture and salt distribution in thick natural stone walls and help in the diagnostics of historic structures and evaluate the salt weathering processes under various climate conditions.

How to cite: Kis, A. and Török, Á.: Seasonal changes of moisture and salt content of historic porous limestone walls; obtained form surface measurements and depth profiles, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-9492, https://doi.org/10.5194/egusphere-egu25-9492, 2025.

Gypsum alabaster is one of the most prominent stones used in European sculpture in medieval and early modern times. Many historical quarries are documented through textual and material evidence (Lipińska, in press) but some remain enigmatic. The “albâtre de Lagny”, a town situated on the banks of the River Marne in the eastern suburbs of Paris, has been mentioned throughout the 19^th century as source for sculpture, notably for the numerous altarpieces now known as English production. This is in obvious contradiction to what 20^th century research found out about the workshops in and around Nottingham using local material. The systematic reference to Lagny, invalidated by material fingerprinting for those and numerous other sculptures, has discredited these earlier sources. It has even been questioned if the gypsum quarried along the Marne River has ever been used for sculpture and the Lagny alabaster was qualified as legend (Bresc-Bautier, 2018; Jugie et al., 2024).

The discovery of an unpublished manuscript, preserved at the Museum of Natural History (MNHN) in Paris, written by one of the most prominent figures of political, legal and scientific life of the late 18^th century, Chrétien Guillaume de Lamoignon de Malesherbes (1721-1794) , sheds a new light on this deposit. Lamoignon provides a detailed description of an alabaster-grade layer in the gypsum quarries of Thorigny, north of Lagny, based on his personal observations and interviews with the workers, a precise stratigraphy, and a list of collected samples. He also visited a workshop in the very centre of Paris using the “Lagny alabaster”, at this time undoubtedly for decorative objects rather than for figurative sculpture. The timeframe for this manuscript is  still uncertain, we can situate it between the French translation of the “Lithogeognosia” of Pott in 1753, the 1759 alabaster essay of Daubenton, both cited by Lamoignon, and his death on the guillotine in 1794.

After transcribing the manuscript and precisely locating the historical quarry, we investigated French collections of geological reference materials and found indeed samples of “Lagny alabaster” from the 19^th and early 20^th century at the MNHN and the BRGM. We are currently completing our corpus of isotope fingerprints of this deposit (Kloppmann et al., 2017), so far based on a single sample provided by the Laboratory of Historical Monuments (LRMH), to better constrain its use for artwork, eventually back beyond the mid-18^th century.

The Materi-A-Net project is supported by the Franco-German FRAL program (ANR-21-FRAL-0014-01 and DFG 469987104) (https://materi-a-net.uni-koeln.de/en/the-project/)

Bresc-Bautier G. (2018) La sculpture en albâtre dans la France du XVIe siècle. Revue de l’Art, 200/2018-2, 37-45.

Jugie S., Leroux L., et al. (2024) L’albâtre et ses sources : incertitudes historiques et ambiguïtés de la documentation levées grâce aux analyses. Technè, 57, 49-59.

Kloppmann W., Leroux L., et al. (2017) Competing English, Spanish, and French alabaster trade in Europe over five centuries as evidenced by isotope fingerprinting. Proceedings of the National Academy of Sciences, 114, 11856–11860.

Lipińska A. (in press) Alabaster. Studies in Material Meaning(s), Studies in Art and Materiality, Leyde, Boston: Brill.

How to cite: Kloppmann, W., Dömling, U., Leroux, L., and Lipińska, A.: „Alabaster from Lagny“, myth or reality?, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-9880, https://doi.org/10.5194/egusphere-egu25-9880, 2025.

One of the most visited historical sites of Budapest is the Heroes’ Square, where a 36 m high Corinthian-style stone column forms part of the Millennium Monument. On the top of the column, a bronze statue depicting Archangel Gabriel is visible. The monument was inaugurated in 1901. The stone column consists of ring-shaped limestone segments (drums). In the conical shape, the drums have a diameter of 2.25  at the lower part of the column, which reduces to 1.9 m at the top. Each drum is 0.5 m high. The condition of the stone column has aggravated in the past 120 years and the current research provides an overview of the actual condition of the stone elements and gives some hints on the preservation of the bronze statue. Tests included the on-site identification of major lithotypes, and testing surface strength and weathering grade using a Schmidt hammer. The moisture distribution was detected using a portable moisture meter. Small samples were collected for laboratory analyses and oriented samples were taken representing the north, east, south and west directions, with different exposure to sun and precipitation, representing different micro-climates. Textural analyses of samples were made by using optical microscopy and SEM-BSE, while mineralogical composition and elemental analyses were performed using XRF and thermogravimetric analyses. The prevailing lithotype is Pleistocene travertine with some textural varieties. The most common weathering forms are black crusts, dissolution features, and green staining of the stone surface from dissolved bronze. The composition of weathering crusts differs from the orientation, namely wind and rain-exposed parts have a different composition than the sheltered ones. The stability of the column was also analyzed. During structural analyses, a minor amount of cracks were also recognized. Loss of renders and dissolution of the stone surface can also cause problems. The study provides an example of integrated research of material properties and structural stability of historic stone structures.

How to cite: Török, Á. and Kis, A.: Diagnostics and preparation of restoration works of a 36 m high stone column holding a giant bronze statue, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-10376, https://doi.org/10.5194/egusphere-egu25-10376, 2025.

The present study investigated the relationship between the Salt Weathering Index (SSI) (Yu & Oguchi, 2010) and WAC, which is one of the methods used to evaluate the physical properties of stone, using various salt weathering experiments on building stones and artificial stones. The stone types studied were tuff (Oya stone, Towada stone, Ashino stone, Nikka stone, Tatsuyama stone), granite (Makabe stone), sandstone (Tago stone, Indian sandstone), porous rhyolite (Koga stone), and brick. Of these, 10 types of bricks, both homemade and commercial, were used. As a result, there was a rough correlation between SSI and WAC, and the multiple linear approximation had the highest coefficient of determination. The reason for the variation in the approximation formula is the difference in rock structure. In other words, for porous rhyolite and some bricks, which were probably fired at high temperatures, the WAC value was higher than the SSI value, whereas, for sandstone and dense tuff which were formed at low temperatures, the WAC value tended to be lower. In addition, the highest coefficient of determination between the rate of dry weight loss (DWL) and the SSI was obtained in the salt weathering experiment using a total immersion method with Na₂SO₄, MgSO₄, and Na₂CO₃ solutions. This is probably because the MgSO₄ solution has the highest viscosity and crystallization occurs in the deeper layers, which flake off on re-immersion. For Na₂SO₄, the coefficient of determination is high, except for the Tago sandstone. Although the reason for this is unclear, it is considered that the Na₂SO₄ precipitated dissolved before it had time to grow sufficiently. In the case of Na₂CO₃, the DWL is high in the Indian sandstone, but this is thought to be because the quartz that makes up the sandstone dissolved in the alkaline solution.

How to cite: Oguchi, C.: Salt Susceptibility Index for various building stones and their practical durability, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12344, https://doi.org/10.5194/egusphere-egu25-12344, 2025.

In many countries, construction, agriculture and livestock sectors produce and emit a large amount of waste and greenhouse gases, accelerating the climate change. For that, new trends and policies for waste management are required due to the high and constant demand for natural resources. The recent activities framed in the green economy are favouring the reuse and recycling of many waste products, in the so-called “Zero Waste” initiatives to reduce the carbon footprint, as well as to the reduction of associated energy expenditure. Among these waste products, those linked to animal by-products not intended for human consumption are usually incinerated for their elimination in Spain, contributing to the emission of CO₂. Consequently, new initiatives are required to promote the reuse of this waste, such as in the development of more sustainable construction products. This paper presents the new results of the SoSCal Project, comparing sets of lime mortar with a proportion of cow hair of 0%, 0.5%, 1%, 2%, 5%, 10% and 12% in weight per kilo of mortar. Some of the advances achieved are that, regardless of the amount of hair added, no cracking process has been observed and the amount of water required can be reduced by 5%, so that extrapolation to larger production quantities would result in significant savings. Although it is necessary to carry out more tests since the workability is compromised, and therefore it will be important to find conditions according to the need for the applicability of the mortar. Another aspect is the increase in the resistance to crystallization of salts with respect to the mortar without fibres, although the durability has been greater in practically all cases, regardless of the quantity of fibres. The addition of hair has affected the thermal properties, specifically the heat transmissivity through the samples, showing a direct relationship between the percentage of added hair and this parameter. The maximum recorded temperatures differed by almost 8°C between the samples without fibres (0%) and those containing 12% of hair after one hour of heating, with the latter also cooling down much faster due to the higher hair content. Based on the results obtained, the addition of animal fibres is showing very positive results compared to the reference mortar. Thus, enhancing the properties of a traditional product, such as lime, compared to Portland cement will also have a very positive effect, since it could reduce the production of this type of cement by having other options, which would also imply reducing the emission of CO₂ into the atmosphere. However, it is necessary to continue with the tests already started and to carry out other tests, especially mechanical and weathering durability tests to evaluate its performance.

Acknowledgements: This study was financially supported by the Research Project TED2021-132417A-I00 funded by MCIN/AEI /10.13039/501100011033 and by the European Union NextGenerationEU/ PRTR

How to cite: Molina-Piernas, E., Pacheco-Orellana, M. J., Martínez-López, J., Domínguez-Bella, S., and Sánchez-Bellón, Á.: Improving the sustainability of lime mortars by reusing cow hair, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12731, https://doi.org/10.5194/egusphere-egu25-12731, 2025.

Daylight is crucial for providing visual comfort, supporting well-being, and creating an energy-efficient environment. However, its integration into historical building conservation remains a vital yet underexplored area, requiring a delicate balance between improving occupant comfort and preserving the historical significance of these buildings.
This research investigates how daylight use is addressed in conservation policies and regulations within Belgium, with a focus on the Flanders region. The study employs a mixed-method approach, combining interviews with professionals in architecture, conservation, and built heritage with a comprehensive review of existing national, regional, and local regulations. These methods aim to evaluate the adequacy of current policies and explore opportunities for improvement.
Key questions addressed include: Which regulations and guidelines govern daylight considerations in restoration efforts? What are the most frequently altered building elements during restoration, and how does daylight integration factor into these changes? Additionally, the study probes the balance between preserving historical authenticity and adapting buildings for contemporary use, assessing whether local policies adequately support this equilibrium.
Findings reveal that while daylight optimization is increasingly recognized as essential for improving occupant comfort, energy efficiency, and the functionality of re-functioned historical buildings, its integration into conservation policies requires greater emphasis. The research highlights the need for interdisciplinary collaboration, such as architects and heritage conservationists working with environmental scientists to design innovative daylighting systems, alongside the development of more comprehensive daylight guidelines aligned with the unique requirements of historical buildings.
By exploring potential improvements to existing policies, this study aims to contribute to a more holistic approach to the restoration of historical buildings, ensuring that they remain both culturally significant and sustainably functional in modern contexts.

How to cite: Sönmez, N., Cılasun Kunduracı, A., and Erkan, Y.: Exploring Daylight Optimization Policies in the Conservation and Restoration of Historical Buildings in Belgium, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13034, https://doi.org/10.5194/egusphere-egu25-13034, 2025.

Marine geology is a relatively young discipline compared to the research conducted on land. In France, while the first draft of a geological map dates back to the 18th century (Guettard, 1746), it wasn't until 1980 that marine data on the metropolitan continental margins were integrated into the geological map at a 1/1,500,000 scale, published by the BRGM. Jean-Étienne Guettard, a physician, botanist, and mineralogist, and a friend of Lavoisier, already had the remarkable intuition of a continuity in geological formations across the English Channel. In 1917, Stanilas Meunier, in his "Geological History of the Sea," boldly claimed that the science of marine geology had French origins.

For a long time, the progress of marine geology was constrained by the barrier of the water column. Therefore, initial information about fossil seas came from land-based studies. In Northern France, particularly along the Boulonnais coast, pioneering work was carried out by Pierre Pruvost (1921, 1924) and Auguste-Pierre Dutertre, the latter writing in 1925 a geological report on Pointe aux Oies and the vicinity of the Wimereux Zoological Station in the Glanures Biologiques, published on the occasion of the Station’s fiftieth anniversary (1874-1924).

Louis Dangeard, one of the great pioneers of French marine geology, was the first in the world to publish a thesis in 1928 on a submarine basin, specifically that of the English Channel, after spending 7 consecutive years (1922-1928) aboard the prestigious research vessel “Pourquoi pas ?” under Captain Jean Charcot. Subsequently, in 1933, he succeeded in forming a team of researchers and students to establish the Marine Geology Center of Caen. In France, the first sheets of the sedimentological underwater map of the Atlantic continental shelf of France at a 1/100,000 scale were published in 1968 by the National Geographic Institute, with a remarkable contribution from Louis Dangeard’s former students: Jacques Bourcart and André Guilcher, along with Gilbert Boillot, Pierre Hommeril, Félix Hinschberger, Pierre Giresse, and Claude Larsonneur, working on state thesis topics focusing on the English Channel.

Subsequent work would be closely tied to technological advancements in marine tools, particularly geophysics, after the first oceanographic expeditions of the N/O Challenger (1872-1877). Using archives and historical sources, we trace here the evolution of marine geological cartography, a brief history of oceanographic vessels, and the exploration tools that gradually shaped the tectono-sedimentary understanding of the English Channel.

How to cite: Gaullier, V.: Birth and Evolution of Marine Geological Cartography: Contribution to the Tectono-Sedimentary Understanding of the English Channel, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-15133, https://doi.org/10.5194/egusphere-egu25-15133, 2025.

Cities are increasingly implementing nature-based solutions (NbS) to mitigate current climate stressors in urban environments, e.g. elevated temperatures and air pollutions levels. Among NbS, ground-based green façades are well-known for their ability to cover a large surface area of vegetation while using minimal ground space. This green initiative consists of climbing plants growing along a vertical surface by either attaching themselves to the surface or using a climbing aid.

Despite the proven benefits of green façades, historic buildings, crucial components of urban environments, are often neglected in urban mitigation strategies. Concerns about potential adverse effects of greening on materials durability and structural integrity, which is currently poorly understood, have limited their implementation on historic buildings. Our research aims to understand the impact of green façades on the degradation processes of historic building materials to unlock the co-benefits of greening built heritage and to explore the potential of green façades as a preventive conservation method.

To achieve this, we analyse the interaction of green initiatives and stone-built heritage in both outdoor and controlled environments. Case studies conducted in the historic city centre of Antwerp (Belgium) over the past two years provided valuable insights on how green façades have an impact on the local microclimate. Monitoring a wide range of environmental parameters, relevant for common degradation processes of built heritage, e.g. surface and air temperature, solar irradiation,  moisture content, amount of wind-driven rain and relative humidity, enables an understanding of the mechanisms of green façades responsible for changes in the local microclimate and identifies the key extrinsic and intrinsic factors affecting the effectiveness of this greenery.  

Our findings highlight the potential of green façades to reduce the risk of common degradation processes affecting built heritage. Green façades significantly reduces solar irradiation and moisture accumulation on wall surfaces, thereby lowering the risk of biodeterioration. It also lowers the maximum surface temperatures by providing shade and tempers the relative humidity fluctuations. This buffering effect reduces the likelihood of salt crystallisation, most common during summer. In winter, evergreen vegetation enhances resistance to freeze-thaw cycles by maintaining higher minimum surface temperatures through thermal blanketing and reducing moisture accumulation on wall surfaces.

This research provides valuable insights into the potential of green façades as a sustainable and preventive conservation method for stone-built heritage. By buffering environmental conditions at the wall surface, green façades can unlock co-benefits: improving urban environments while enhancing the durability of historic building materials. A deeper understanding of the behaviour of green façades on the degradation of historic building materials can support their implementation in urban environments, ensuring that stone-built heritage becomes more resilient to current and future climate challenges.  

How to cite: De Groeve, M., Kale, E., Orr, S. A., and De Kock, T.: Implications of green façades on historic building materials, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-15240, https://doi.org/10.5194/egusphere-egu25-15240, 2025.

Advances in the accessibility of surveying and geoscience tools and developments in computer science have led to significant growth and rapid developments in the efficiency and accuracy of heritage documentation practices from objects to entire buildings and complexes. Modern cultural heritage research relies heavily on producing accurate 3D models using digital documentation methods such as photogrammetry and laser scanning. Innovative approaches to 3D documentation through digital photogrammetry and laser scanning provide the opportunity to create digital twins of real cultural heritage monuments. For these digital twins to be relatable to the real world for quantitative analysis, they must be scaled and oriented in some way. The most common method for accurately scaling 3D models is through the use of markers. Markers ensure accurate spatial measurements by linking coordinates in the model to real-world coordinates. These markers help in image orientation, calibration, and 3D reconstruction. Despite their common use, currently, there is no set of designed markers that can be universally used across various modeling methods and software. The present investigation aims to identify different types of markers used for commercial and research purposes, comparing and contrasting their type, accuracy, and suitability for specific applications. Based on an evaluation of existing software solutions and indicators through laboratory tests, the qualities of markers will be analyzed and evaluated to facilitate precise 3D modeling and improve the reliability of data collected through photogrammetry and laser scanning. The effectiveness of markers will be analyzed through comparative studies investigating how different configurations and types of markers affect the overall accuracy and effectiveness of reconstructed 3D models of photographed objects. The findings are intended to provide insight into best practices for selecting and implementing markers in archaeological surveys, contributing to more accurate and reliable results from modeling, creating newly developed innovative markers, and allowing broader applicability for precise 3D modeling of photographed national cultural heritage sites.

Acknowledgments: The authors would like to thank the Bulgarian National Science Fund for funding the research under the project  "An integral approach in creating digital twins of archeological immovable monuments using innovative technologies", contract КP-06-Н82/1 - 06.12.2024.

How to cite: Pashova, L., Lirkov, I., Raykovska, M., Petkov, N., Georgiev, P., Jones, K., Kabadzhova, H., Evtimov, G., Vasilev, G., Harizanov, S., and Borisov, M.: Comparative analysis of digital markers in photogrammetry and laser scanning for documentation of archeological immovable monuments, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-16284, https://doi.org/10.5194/egusphere-egu25-16284, 2025.

Rock erodibility is an intrinsic property defined as the vulnerability of a rock to erosion (Martínez-Martínez et al., 2024; doi: 10.1201/9781003429234-177). Intuitively, erodibility is a key concept in cultural heritage conservation, especially in studies concerning the exposure of building materials to wind, rain, hail, and human activity. However, research on its implications for heritage conservation remains scarce.

Abrasion resistance of rocks is a property routinely measured in geomechanical laboratories and it offers a practical approach to assessing the erosion susceptibility of the material. Two standardized methods, the Böhme abrasion test and the Wide Wheel Abrasion test, are widely used to evaluate abrasion resistance in dimension stones. However, these methods require both large and numerous samples, rendering them unsuitable for cultural heritage studies, where sampling is severely limited. To overcome this limitation, a modified version of the Böhme abrasion test is proposed. This adaption uses a plate grinding machine commonly employed for preparing rock thin sections, making the procedure widely accessible in geoscience laboratories.

The standardized Böhme Abrasion test requires cubic samples of 71 mm size, place on a grinding plate and subjected to an abrasive load of 294N for 16 cycles of 22 turns each. Wear is calculated from the loss in volume and weight. In contrast, the modified procedure uses smaller prismatic samples (20×30×30 mm) and a plate grinding machine operating at 30 cycles per minute under a load of 0.02 N/mm². Sample dimensions and weight are measured at the beginning of the test. Each sample is abraded for 15 minutes on two perpendicular surfaces, and the final dried weight is recorded (Martínez-Martínez et al., 2017; doi: 10.1016/j.buildenv.2017.05.034). Material loss is quantified as the modified Böhme Abrasion Loss (mBAL), calculated using the equation

mBAL = ΔV = Δm/ρ_b

where ΔV is the volume loss (in mm³); Δm is the mass difference (in g); and ρ_b is the bulk density of the rock.

This modified procedure was validated using a variety of commercial dimension stones, including limestones, marbles, travertines, tuffs, calcarenites, calcirrudites, sandstones, quartzites and slates. Results where compared to those obtained with the standardized Wide Wheel Abrasion test on the same rock types. A strong correlation (R²=0.87) was observed between the two methods, expressed by the equation

mBAL = 8.9 T_ww – 86.5

where T_ww the wear trace measured in the Wide Wheel Abrasion Test.

This modified approach offers a viable solution for assessing erosion susceptibility in heritage contexts, enabling reliable quantification with minimal material requirements. It offers a valuable tool for developing effective conservation strategies for cultural heritage.

This work was supported by grant numbers PID2020-116896RB-C21 and PID2020-116896RB-C22 funded by MCIN/AEI/ 10.13039/501100011033

How to cite: Martínez-Martínez, J., Berrezueta, E., Benavente, D., and Kóvacs, T.: Preliminary proposal for an experimental method to measure erosion susceptibility of heritage stones, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17798, https://doi.org/10.5194/egusphere-egu25-17798, 2025.

Short- and long-term variability in indoor microclimate conditions within conservation spaces (museums, galleries, archives, and libraries) can exacerbate the risk of deterioration of cultural materials. Active microclimate control systems are often installed to stabilize thermo-hygrometric conditions, conversely, massive buildings with thick walls are less affected by outdoor conditions due to their high thermal inertia. Historic reinforced concrete structures, like bunkers and fortifications, are often windowless, further providing stable microclimate and protecting sensitive materials from photodegradation. World War II (WWII) bunkers often labeled as “dark” or “painful heritage”, were initially perceived only as symbols of war and occupation, leading to neglect and material deterioration over time. However, the impossibility of their demolition gradually encouraged interest towards their reuse, raising awareness of their social, historical, and economic potential. This contribution provides a comprehensive microclimate analysis to support management strategies in a unique case study: the NTNU (Norwegian University of Science and Technology) library for cellulose-based materials, hosted within “Dora I” WWII bunker in Trondheim, Norway (63.43° N 10.40° E). The archive spans 3700 m² and contains around 5200 m³ of collections, including ancient volumes, journals, newspapers, and pictures. “Dora I”, a massive reinforced concrete German submarine and terrestrial fortification with 3.5 m-thick walls, covers a total area of approximately 16,000 m². 10 thermo-hygrometers compliant with European standards were installed, ensuring representativeness of indoor conditions across two floors. Time series of air temperature (T) and relative humidity (RH) are significantly longer (7 years, since 2018) than most studies in the literature, and are continuous and complete with minimal number of missing values. Statistical approaches from climatology are applied to analyse T-RH data, decomposing time series into short-term (daily/noise) and long-term (seasonal) variability (extracted by sinusoidal fits) to provide insights into indoor climate dynamics. A comprehensive conservation risk assessment, based on dose-response functions, evaluated biological and chemical threats to archival materials using both raw and filtered (i.e., “clean”) microclimate data. This approach allows to examine how anthropogenic factors (e.g., access and archival management) in the noisy signal may exacerbate climate-induced conservation risks. The findings demonstrate the exceptional features of this massive building, where peak summer temperatures occur indoors 2 to 2.5 months later than outdoors, depending on sensor location. The study estimates no biological risks for cellulose materials from humidity-dependent insects or mould growth, with temperature-dependent insect degradation that remains a threat, particularly from June to December (although it has decreased over time). Chemical degradation risks, confirmed by three indicators, remains significant from July to October. This is evident when considering raw microclimate data, which reveals slight but still significant variations in risky days compared to "clean" data, suggesting a potential influence of human activities related to archival management. In conclusion, the findings underscore the benefits of massive structures in preserving vulnerable materials and a useful methodological approach in combining raw and filtered microclimate data to assess conservation risks. Analysing noise signal may inform conservators about the impact of their management practices, offering a useful framework for similar archival contexts worldwide.

How to cite: Boccacci, G., Frasca, F., Bertolin, C., Dahlin Saeter, T., Lund, E., and Siani, A. M.: Climate-induced Risk Assessment of Library Collections within Dora I WWII Bunker in Trondheim, Norway, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-18457, https://doi.org/10.5194/egusphere-egu25-18457, 2025.

The site of Mnajdra, one of the UNESCO-listed Megalithic Temples of Malta (https://whc.unesco.org/en/list/132)  dating back to 3600 - 2400 BC, is located on the southern coast of the Maltese archipelago. This site, along with two other similar sites, was sheltered in 2009 with reversible, open-sided shelters, with the aim of mitigating the critical impact of the aggressive marine environment on the conservation of the limestone megaliths.  Environmental conditions such as rain, wind, salt damage and direct insolation - triggering thermoclastism (thermal stress)- were identified as a key factor contributing to the progressive stone weathering and are currently being monitored by a multidisciplinary study.

This abstract will focus on understanding the impact of these protective, open-sided shelters on the temperature variations of the Mnajdra’s façade, with particular attention to diurnal and seasonal fluctuations, comparing to data available from the pre-sheltering period. Other studied environmental factors will not be addressed here.

The Mnajdra complex is widely recognized for its astronomical alignment, with the main (eastern) façade oriented to mark the equinoxes, solstices, and other solar events. In order to retain the association of the Temples with these alignments and to continue to observe these events, the shelters were designed to remain more open on the eastern side. As a result, surface temperature variations are currently monitored on the eastern façade, where direct sunlight could cause significant temperature fluctuations with possible subsequent deterioration effects such as microcracks formation and progressive material weakening.

Thermal imaging data was thus collected across two seasons - autumn (9th October 2023) and summer (19th June 2024) at 10-minute intervals during morning hours to identify trends of the fluctuations.

Results from these two campaigns revealed significant surface temperature fluctuations in autumn and lower variations in summer. Surface temperature gradients were observed, with a more intense gradient in autumn (from 27,8°C at 7.50 am to over 35°C at 8.50am), and less intense fluctuation in summer (from 27,3°C at 6.50am to 30,4°C at 7.50am). In both seasons, hotspots were identified particularly in areas of different megaliths (of the same stone type) where prolonged exposure (approximately 1h) to direct solar radiation occurred.

Taking into account the difference in air temperature recorded during the acquisition (19-25°C in October and 26-32°C in June) this difference can possibly be attributed to the inclination of the sun. The more significant surface temperature fluctuations observed in autumn are likely attributed to the angle of solar incidence at that time. The sun reaches the studied megaliths more directly in autumn and less directly in the summer solstice, resulting in greater variations in surface temperature.

This study forms part of a broader multidisciplinary project integrating non-invasive analytical techniques and environmental parameter modelling to evaluate the efficacy of sheltering systems. All the findings will provide scientific data to inform conservation strategies also aiming at mitigating the progressive weathering on these unique heritage sites, and ensuring their long-term preservation sites also in projection of increasing challenges due to the impacts of climate change.

How to cite: Faieta, R., Cassar, J., Valantinavičius, M., and Micallef, D.: Understanding some of the effects of shelter design on deterioration at the Mnajdra Megalithic Temples of Malta, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-18921, https://doi.org/10.5194/egusphere-egu25-18921, 2025.

Recognizing the inestimable value of the UNESCO World Cultural Heritage Sites for future generations, it is necessary to be aware of their vulnerability to multi-risks in the context of global climate change and the growing interest and engagement of citizens and stakeholders.

Romania is home to nine categories of cultural heritage sites (CHSs) – the Horezu Monastery, the Churches of Moldavia, the Villages with Fortified Churches in Transylvania, the Dacian Fortresses of the Orăștie Mountains, the Wooden Churches of Maramureş, the Historic Centre of Sighişoara, the Roșia Montană Mining Landscape, the Brâncuși Monumental Ensemble of Târgu Jiu, and the Frontiers of the Roman Empire – Dacia.

This work has been partially developed in the frame of two projects: 10101/2024-UB SPAH, funded by the University of Bucharest, which emphasizes sustainable and participatory activities in heritage-aware communities facing geographical risks, and 395080/2024 GeoAlliance, titled “Driving Sustainable Urban Futures:  A Romanian-Norwegian Innovation Geophysical Alliance for Green Transition and SMART City Development”. Supported by the EEA and Norway Grants, the latest project provided geophysical data for representative sampling urban of cultural heritage sites, underscoring the significant role that geophysics play in enhancing urban resilience. Results were integrated within a multi-criteria analysis (MCA) to assess the vulnerability of CHSs in Romania to both natural and man-made hazards. To apply the multicriteria analysis of CHSs vulnerability, a GIS database was developed with both natural and human-induced processes such as earthquakes, landslides, floods, that threaten the cultural heritage proprieties, being identified, mapped and ranked. This was followed by mapping the multi-hazard susceptibility features across the nine categories of the UNESCO World CHSs. The next step involved inventorying the specific attributes of each cultural heritage site that contribute to their vulnerability to various hazards and impact their resilience.  The vulnerability assessment considered several intrinsic factors that can increase exposure to hazards. Key factors include the age and the height of the structure, the elevation and the level of insulation, the used construction materials, and foundation depth. Additionally, the effectiveness of modern infrastructure, especially the underground water pipes and sewage performance, along with shallow hydrogeological and geophysical induced changes, significantly influences their risk. Other important considerations included visitor numbers and the degree of degradation of the construction, as well as ongoing consolidation and renovation efforts.

The findings from multicriteria analysis revealed the most susceptible cultural heritage sites to both natural and human-induced hazards. The paper emphasizes that although many heritage sites are highly exposed to multiple hazards, some of these sites have lower vulnerability despite being susceptible to these threats. Additionally, certain hazard processes that initially seem harmless to the CHSs are long-term damage. The results of the present work can serve as a valuable resource for site managers, enabling them to better understand where the vulnerabilities of their managed site reside and to intervene with higher efficiency in day-to-day monitoring and maintenance. Additionally, the insights can assist central and local authorities in comprehending financial requirements and allocating the necessary budget for protection and management efforts in order to strengthen CHSs protection.

How to cite: Popovici, D., Andra-Toparceanu, A., Chitea, F., Armaș, I., Ovreiu, A. B., Malvica, S., and Carboni, D.: Assessment of UNESCO Cultural Heritage Sites Vulnerability through Multicriteria Analysis, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-19597, https://doi.org/10.5194/egusphere-egu25-19597, 2025.

In Roman Baetica and specifically in the city of Gades (Cádiz, Spain), studies about Roman mural paintings has been mainly approached from a traditional perspective, with specific exceptions where archaeometric studies have been carried out on this type of construction and decorative materials. During an archaeological intervention carried out in the Santa Bárbara car park in Cádiz between 2009 and 2012, several Roman mural paintings fragments from the levels of waste deposits were documented. The archaeological record has allowed the levels to be dated between the 1st century BC and the 1st century AD., thus this set of pictorial remains belongs to the Republican phase or to the initial stage of the Augustean period of Gades, a period with hardly any examples of pictorial representations from the early times in Baetica. Due to the number of fragments of Roman paintings with a great variety of colours, several analytical methodologies to know the composition, technique and quality of the paintings were carried out by means X-ray diffraction, X-ray fluorescence spectroscopy, Raman spectroscopy, FTIR, polarized optical microscope, scanning electron microscope, cathodoluminescence microscope and spectrophotometry. A representative set of 31 samples was chosen for this study. Some samples only show a single layer of paint on the mortar, but it is more frequent to find several overlapping layers. The colour palette presents: light and dark blue; bright, light and dark red; purple; light and dark yellow; light green and green; white, brown and lampblack. These colours were identify as egyptian blue, cinnabar, hematite, iron ochers, celadonite, calcite, black, and mixtures between them. On the other hand, the mortars characterization showed two types, the first one is the most numerous and were used as substrate for all identified colours, except for pure black. In fact, fragments that only presented the black pigment, sometimes with lines in white, have been identified on the intonaco layers with ceramic. This remains probably corresponded with a prominent Roman urban villa placed in the Eriteia island of Gades, confirming the importance that this city had within the Roman Empire.

Acknowledgements: This study was financially supported by the Research Project TED2021-132417A-I00 founded by MCIN/AEI /10.13039/501100011033 and by the European Union NextGenerationEU/PRTR, and the Research Project “La gestión de los residuos sólidos en Gades. Aproximación a la caracterización tipológica de los vertidos y su inserción en el entramado urbano de una ciudad costera” (CEIJ-006) Fundación CEiMAR.

How to cite: Domínguez-Bella, S., Lara Medina, M., Pascual Sanchez, M. A., and Molina-Piernas, E.: Archaeometrical characterization of the Roman wall paintings from Gades (Cádiz, Spain)., EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20444, https://doi.org/10.5194/egusphere-egu25-20444, 2025.

Measuring the ultrasonic pulse velocity of stone ashlars belonging to masonry structures provides useful indications for assessing the materials' strength and state of conservation, the need for their possible substitution, and the effectiveness of consolidating treatments. Ultrasound techniques as nondestructive tests preserve the integrity of masonry buildings that especially in Italy often have a cultural and historical-artistic value.
Several correlations linking ultrasonic velocity with the compressive strength of stone materials are available in the literature. These correlations are often developed in the laboratory using small-size samples, high measurement frequencies, and direct transmission measurement modes. In situ, it is often difficult to make measurements under such conditions due to the inaccessibility of both the surfaces of materials and the higher dimension of the elements to investigate. In addition, material surfaces are often affected by deterioration which causes problems in the transducer coupling with measurement surfaces. Furthermore, the use of coupling agents is usually forbidden in the case of artistic artifacts. The ultrasonic tomograph with pulse-echo technology (PE UT) overcomes such difficulties. Pulse-echo method introduces a stress pulse by a transmitter into an object at an accessible surface. The pulse propagates into the test object and is reflected by flaws or interfaces. The surface response caused by the arrival of reflected waves, or echoes, is monitored by receivers. Tomography gives visualization, either by cross-section or 3D images, of the interior structure of the object to find anomalies and determine the material physical properties. PE UT has an array of dry-point contact transducers (DPCT) that enable ultrasonic measurements on rough surfaces without coupling gel, reducing the measuring time and test invasiveness. PE UT employs transverse S-waves instead of longitudinal P-waves because they give more reliable results for degraded materials and in the presence of defects. In the literature, there are several studies in which tomographic images were used to detect the presence of defects in concrete and rock members. In these cases, a reference value of UPV is assumed. On the contrary, few studies use PE UT images to determine UPV on concrete or stone members. Thus, the appropriateness of this technique to assess UPV is still under research due to the lack of a sufficient number of published experimental studies.
In the present paper, the reliability of PE UT in determining the ultrasonic velocity of soft calcarenitic stone elements, known as Lecce stone, is investigated. The measurements are compared with those conducted with conventional transducers at different frequencies in direct and indirect modes. The measurements are also carried out considering the presence of water in the material, which strongly influences not only the ultrasonic measurements but also the strength of the material itself. Four levels of saturation from dry to fully saturated states are considered. The results of the experimental campaign evidence that PE UT is a reliable technique for UPV assessment, allowing rapid one-side measurements on surfaces in different conditions.

How to cite: Vasanelli, E., Di Gennaro, D., Sticchi, M., Blasi, G., and Aiello, M. A.: The use of ultrasonic pulse-echo tomography to assess UPV in soft calcarenitic stones, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20560, https://doi.org/10.5194/egusphere-egu25-20560, 2025.

Mangrove sediments are natural carbon sinks that may act as key components for climate change mitigation. To investigate the characteristics and distribution of the carbon-dense muds in the coastal mangrove areas of northern Taiwan, we applied both floating and submerged electrodes for subsurface resistivity imaging. After collecting the apparent resistivity data, we conducted 2D resistivity inversion and 3D modeling. Our results show that the muddy sediments are characterized by low resistivity and are primarily found in the top ten meters below the riverbed. On the other hand, a higher resistivity layer, probably indicating coarse-grained sediments, is situated below the muddy layer. Although the submerged electrodes generally provide the best data quality, the floating electrodes efficiently image the bottom of the muddy sediments. Therefore, we recommend that a combination of floating and submerged electrode methods for resistivity imaging should be an efficient approach to investigate mud distribution in mangrove sediments with shallow water depths.

How to cite: Han, W.-C., Lin, K.-I., Chen, L., and Liu, H.-C.: Electrical resistivity imaging of mangrove sediments, northern Taiwan, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2366, https://doi.org/10.5194/egusphere-egu25-2366, 2025.

Heavy Rare Earth Elements (HREEs) are critical for the production of most electronic devices. Rapidly increasing demand for these minerals has led to a proliferation of highly polluting makeshift HREE extraction in Myanmar. Monitoring the spread of these mines is important for the preservation of human health and the environment. This paper utilizes a geospatial foundation model pre-trained using self-supervised learning to detect hundreds of rare earth mines using a single template example. This is achieved through the development of a novel method for embedding similarity search-- Cosine Contrast-- which leverages both positive and negative templates to yield more relevant results. 

How to cite: Ballinger, O.: Monitoring Illicit Rare Earth Mining in Myanmar via Self-Supervised Learning, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4496, https://doi.org/10.5194/egusphere-egu25-4496, 2025.

Coalbed methane (CBM) is considered an unconventional gas resource. Accurate determination of CBM content can provide potential disaster warnings and guide exploration and development. Direct measurement and statistical analysis of CBM content are common techniques. Hoverer，direct measurement methods have high accuracy, but they are time consuming, labor intensive, and inefficient; statistical methods have a limited ability to solve complicated nonlinear problems, for example, CBM content prediction commonly used computational methods do not have high enough accuracy due to the small amount of training data and the shallow model structure. 3D seismic exploration has been widely used in CBM exploration and development due to its small grid size and high resolution. It will improve the accuracy of coalbed methane prediction to combine 3D seismic data with coalbed methane content. Machine learning techniques are a set of computational methods that can learn from data and make accurate predictions. In recent years，many applications of machine-learning techniques for CBM content prediction are found to be more reliable，however the results from traditional machine learning models have errors to some extent. A CBM content model based on Deep Belief Network (DBN) has been developed in this paper, with the input as continuous real values and the activation function as the rectified linear unit. Firstly, various seismic attributes of the target coal seam were calculated to highlight its features, then the original attribute features were preprocessed, and finally the performance of the DBN model was developed using the preprocessed features. Different from conventional DBN models, the proposed model uses continuous real values as the input and the rectified linear unit (ReLU) as the activation function. Training process includes pre training and fine-tuning. Pre training gives the model good initial parameters by training with unlabeled data, and fine-tuning uses a standard supervised method with labeled data to optimize the model. This paper successfully applied a DBN model to predict CBM content from a CBM 3D seismic  prospecting district. With more layers pre trained, the average error decreased from 3.69% to 2.16% and from 2% to 5.76% for the maximum error. Using a pre training strategy to initialize the model’s parameters can improve the accuracy of the model results. Compared with the typical multilayer perceptron（MLP）and the support vector regression（SVR）models, the DBN model has the smallest error, which means it is more accurate in predicting CBM content than the other two models.

How to cite: Du, W., Peng, S., and Cui, X.: Coalbed methane content prediction based on deep belief network, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4908, https://doi.org/10.5194/egusphere-egu25-4908, 2025.

The São Domingos Mine (Mértola, Portugal) is an abandoned sulphide mine whose exploitation has had a long-term impact on its soil and water contamination problem covering an area of ​​approximately a length of 20 km and a width of 2 km. The mining heaps are spread along a watercourse that flows into the Chança River dam, which merges with the Guadiana River, both international rivers. This constitutes a serious environmental problem leading to contamination by heavy metals (HMs). Contamination assessment is a slow process that involves collecting soil samples for HMs analysis.

The study of mining heaps using geophysical and geospatial methods allows us to determine their depth and the volume of accumulated materials, as well as their characterization in relation to soils contaminated by HMs. We propose the use of electromagnetic induction, electrical resistivity tomography and GNSS methods to carry on the analysis.

This work is part of an interdisciplinary study that is being carried out within the scope of the INCOME Project (Inputs for a more sustainable region – Instruments for managing metal-contaminated areas). The aim is to combine data from Geophysics, Chemistry and Remote Sensing to create a tool, using Artificial Intelligence, that allows the calculation of contamination maps using less data than standard methodologies.

This is a sustainable management model that will increase optimization and reduce resources spent in the sampling and analysis phases. Moreover, the model aims to provide important real-time information for decision-making subjected to monitoring and managing pollution. It also has a high replication potential for other contaminated environments, such as landfills, industry or even intensive agriculture.

Funding: The work was supported by the Promove Program of the “la Caixa” Foundation, in partnership with BPI and the Foundation for Science and Technology (FCT), in the scope of the project INCOME – Inputs para uma região mais sustentável: Instrumentos para a gestão de zonas contaminadas por metais (Inputs for a more sustainable region: Instruments for managing metal-contaminated areas), PD23-00013. Acknowledgment: CREATE Project (R&D Unit ID 6107).

How to cite: Oliveira, R. J., Caldeira, B., Borges, J. F., Teixeira, P., Rodrigues, G., Costa, M. J., Palma, P., Custódio, M., Catarino, A., and Semedo, N.: Geophysical and geospatial characterization of mining heaps of the São Domingos Mine (Mértola, Portugal), EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7010, https://doi.org/10.5194/egusphere-egu25-7010, 2025.

Many endocrine-disrupting chemicals (EDCs) are discharged into the aquatic environment mainly due to their incomplete removal during biological treatment at municipal wastewater treatment plants. For this reason, advanced oxidation processes (AOPs), using ozone with other oxidant agents, like hydrogen peroxide, are effective in removing EDCs. Furthermore, to reduce the risk of drinking water contamination by EDCs, it is necessary to ensure a real-time monitoring of wastewater treatment processes. Fluorescence spectroscopy could be used for wastewater quality monitoring to control the fate of EDCs in water systems. However, the complex physical, biological and chemical process involved in wastewater treatment process exhibit non-linear behaviors, which are difficult to describe by linear mathematical models. The artificial neural networks (ANNs) have been applied with remarkable success in several modeling studies including the highly non-linear ones.

The main objective of the present work was to use fluorescence data and ANN to monitor two EDCs, namely a pesticide (Diuron) and a pharmaceulical and corrosion inhibitor (Benzotriazole) during advanced wastewater treatments.

The data used were obtained from the pilot plant installed and operated by AquaSoil at the municipal wastewater reclamation plant of Fasano (Brindisi, Italy). The influent wastewater was obtained from tertiary treatment consisting of a coagulation stage by aluminum polychloride, sedimentation stage in lamella clarifiers and disinfection stage by sodium hypochlorite. An aliquot of the tertiary effluent was redirected to the pilot plant employing the O₃/H₂O₂ advanced oxidation process. This process was operated in the patented technology commercialized by AquaSoil as MITO₃X.

Diuron and Benzotriazole were analyzed using standard methos. Fluorescence data were collected using a Shimadzu RF-5301PC fluorescence spectrophotometer at different excitation emission wavelengths, while ANN model has been developed using Matlab software with ANN toolbox to match the measured and the predicted concentrations of EDCs.

The concentrations of Diuron and Benzotriazole were well correlated with selected fluorescence indexes. The combination of differente fluorescence peaks enhanced the determination coefficients of the single and multiple linear regressions. The developed ANN model that incorporated as input parameters the values of the fluorescence indices strongly enhanced the prediction of the fate of Diuron and Benzotriazole during AOPs. Therefore, the ANN-based model have been found to provide an efficient and robust tool in predicting the fate of EDCs removal. The comparison between ANN predicted data and experimental data shows the ability of artificial intelligence tools to predict EDCs concentrations with high accuracy and precision. Moreover, this model requires no additional information on the mechanism and the kinetics of chemical degradation of target contaminants. Since ANN have valuable advantages such as learning ability, dealing with imprecise, noisy and highly complex non-linear data, and parallel processing ability and due to the high sensitivity of fluorescence, it is expected that the developed fluorescence-ANN based model can be successfully applied for real-time control of AOPs employed for EDCs removal. This may also lead to AOPs optimization and cost savings.

How to cite: Roccaro, P., Fazzino, F., Spadaro, M. R., Gagliano, E., and Santoro, D.: Modelling the fate of endocrine-disrupting chemicals during wastewater ozonation by fluorescence and artificial neural network, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7399, https://doi.org/10.5194/egusphere-egu25-7399, 2025.

According to the European Union Soil Strategy for 2030, it is crucial to address contamination from mining areas, and its impact on watercourses. to achieve these goals, it is essential developing methodologies for identifying and monitoring contaminated areas, and implementing sustainable solutions for their recovery to protect soil health and ensure sustainable land use. In Portugal, soil and water contamination in former mining areas, is a significant environmental challenge, especially due to the presence of potentially toxic metals that can affect human health and ecosystems. São Domingos mine, located in the Iberian Pyrite Belt, is an open-pit mine, submerged in acidic drainage water, resulting from mining extraction activities carried out until the middle of the 20^th century. In this sense, the objective of this study was to analyze the chemical and biological characterization of the soils of the São Domingos Mine, contributing to the development of an environmental management model for abandoned mining areas. To achieve this purpose, 11 topsoil (0-20cm) samples (A2 to A12) were collected in São Domingos mine, and the following parameters were analyzed: (i) chemical: pH (deionized water suspension of 1:2.5 (w/v)); electrical conductivity (EC) (deionized water suspension of 1:2 (w/v)); phosphorus (P) and potassium (K) (Egner-Riehm Method); total nitrogen (N) (Kjeldah method); organic matter (OM) (Walkley & Black method); (ii) biological(enzymatic parameters): dehydrogenase activity, acid phosphatase activity and β-glucosidase activity. The results evidenced pH ranged from 3 to 4 (very acidic). The EC, ranging from 115 to 5043 µS/cm, with most of the samples classified as non-saline. The percentage of OM was generally low (0.2 to 2.5%). Regarding macronutrients, the results were equally limiting, with the samples showing low levels of N (0.05 to 0.17%), P (1 to 6 mg P₂O₅ kg^-1) and K (3 to 30 mg K₂O kg^-1). Analysis of enzyme parameters revealed low enzymatic activity frequently lower than the detection limit of the technique. An exception to β-glucosidase that generally had low values, (0.01 to 0.40 µmol PNP g^-1 DM h^-1), and phosphatase showing values among 0.27 to 0.96 µmol PNP g^-1 DM h^-1. This can be mainly related to the low values of pH, low percentage of organic matter and nutrients, and high amount of potentially toxic metals. These results will be extremely important in the development of the environmental management model proposed in INCOME project, as they provide essential information on the variability of the contamination in the mine area, essential information for validate the rest of the methodologies applied. Further, this type of model will be applicable to other regions of contamination, contributing to economic and tourist development, public health, and protection of local ecosystems, in line with the Sustainable Development Goals.

Funding: The work was supported by the Promove Program of the “La Caixa” Foundation, in partnership with BPI and the Foundation for Science and Technology (FCT), in the scope of the project INCOME - Inputs for a more sustainable region: Instruments for managing metal-contaminated areas, PD23-00013. Acknowledgment: CREATE Project (R&D Unit ID 6107).

How to cite: Semedo, N., Custódio, M., Catarino, A., Rodrigues, G., Teixeira, P., Oliveira, R. J., Palma, P., Caldeira, B., and Costa, M. J.: Soils chemical and biological characterization tools for managing metal-contaminated areas: case-study São Domingos mine (South of Portugal), EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-10841, https://doi.org/10.5194/egusphere-egu25-10841, 2025.

The INCOME project (Instruments for Managing Areas Contaminated by Metals) proposes the development of an environmental management model for mining soils contaminated by metals. This study presents preliminary results obtained using the Multispectral Imager (MSI) aboard the European Space Agency's (ESA) Sentinel-2 satellite to identify contaminated soils in the São Domingos Mine, located in southeastern Portugal.

The MSI instrument offers significant advantages, including high spatial resolution (10, 20, or 60 m depending on the spectral band), open access for rapid image download, and frequent revisitation of the study area. The preliminary analysis focuses on identifying areas with fully exposed soil using spectral indices, which combine spectral measurements at different wavelengths to improve classification accuracy. Additionally, the Random Forest (RF) method, a widely recognised approach to general-purpose classification, was tested. Contaminated soils characteristically exhibit discrepancies in optical properties, such as distinct colouration, which can also be detected in the visible region bands of the MSI instrument. The Shortwave Infrared (SWIR) bands are particularly efficacious for identifying heavy metals.

The designated soil areas will be subject to monitoring for metal contamination utilizing the MSI instrument, with the prospective incorporation of hyperspectral data from satellites such as the Environmental Mapping and Analysis Program (EnMAP).

Funding: The work was supported by the Promove Program of the “la Caixa” Foundation, in partnership with BPI and the Foundation for Science and Technology (FCT), in the scope of the project INCOME – Inputs para uma região mais sustentável: Instrumentos para a gestão de zonas contaminadas por metais (Inputs for a more sustainable region: Instruments for managing metal-contaminated areas), PD23-00013. Acknowledgment: CREATE Project (R&D Unit ID 6107).

How to cite: Rodrigues, G., Teixeira, P., Oliveira, R. J., Costa, M. J., Palma, P., Caldeira, B., Custódio, M., Catarino, A., and Semedo, N.: Preliminary Assessment of Metal Contamination in Mining Soils Using Sentinel-2 MSI: A Case Study of São Domingos Mine, Portugal, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-11957, https://doi.org/10.5194/egusphere-egu25-11957, 2025.

Traveltime tomography recovers the background velocity field by minimizing the difference between observed and theoretical traveltime. Due to its computational efficiency and robustness, this method has been widely applied in studies of Earth's internal structure, oil and gas exploration, and other fields. However, most existing studies rely on regular rectangular grids for tomography, which exhibit limited adaptability when dealing with irregular topography and subsurface interfaces. The utilization of unstructured triangular meshes are more suitable for handling such complex study areas, and the development of traveltime tomography based on triangular meshes is necessary.

Compared with rectangular grids, the inversion method based on triangular meshes faces more complex gradient computation formulas, which has, to some extent, hindered the development of traveltime tomography. To address this challenge, we introduce automatic differentiation (AD) method to calculate the gradients more automatically, enabling the implementation of traveltime tomography based on triangular meshes. After building the forward computational graph, AD method can compute the gradient using the chain rule, thereby saving a lot of manpower in theoretical derivation, coding, and other processes. In this study, we used a finite difference method based on triangular meshes to solve the eikonal equation, accurately and efficiently calculating the traveltime in complex structural areas. Then, we integrate the eikonal solver into the current deep learning framework (e.g. pytorch), and update the velocity model with its built-in optimization algorithm after calculating the gradient in AD method. The process of traveltime tomography is completed on GPU, which can fully utilize the computing power of GPU and efficiently calculate inversion. Numerical tests indicate that the method can achieve promising inversion results and provide a suitable initial model for the full-waveform inversion. Our research provides a new approach for seismic inversion with unstructured grids, which is helpful for high-precision imaging of complex structural areas.

How to cite: Chen, X., Zhang, T., Cao, D., and Liao, W.: Traveltime tomography on the triangular mesh based on automatic differentiation, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14686, https://doi.org/10.5194/egusphere-egu25-14686, 2025.

      In recent years, due to the enhanced interference-resistance of airborne gravimeters and the advanced gravity anomaly calculation techniques, the China Geological Survey has carried out numerous airborne gravity survey missions in mid-high mountainous and deeply incised regions, including Tibet, Xinjiang, and Gansu. In practical applications, the measured free-air gravity anomalies need to have local topographic corrections and intermediate layer corrections to obtain Bouguer gravity anomalies for geological interpretation. Currently, commercial airborne gravity terrain correction software adopts the Nagy flat-topped prism method for near-field areas and the rod formula for far-field areas. This approach results in poor continuity between different terrain correction zones and fails to effectively eliminate terrain effects in deeply incised areas. This paper presents a novel method. By utilizing the coordinate surfaces in the spherical coordinate system, namely conical surfaces and semi-planes, the area is divided into rings (m rings) and blocks (n blocks), forming m×n "sectorial spherical shell blocks". A terrain correction calculation formula for these "sectorial spherical shell blocks" in the circular domain is derived, unifying the terrain correction formulas for both near and far regions. This unification allows for seamless connection among various terrain correction areas and obviates the need for intermediate layer corrections. The method has been validated by theoretical models, showing reliable accuracy in terrain correction value calculations. It has also been successfully applied in the West Kunlun airborne gravity survey. When compared with commercial software, it effectively eliminates terrain effects and achieves better terrain correction results.

How to cite: Wang, L., Xue, D., Wang, G., Teng, D., and Zheng, J.: Aerogravity terrain correction method based on spherical coordinate system, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-15987, https://doi.org/10.5194/egusphere-egu25-15987, 2025.

In the realm of railway infrastructure, the safety of railway road base structures is of paramount importance. A conventional railway raod base is composed of three distinct layers: square cement sleepers positioned at the top, ballast situated in the middle, and undisturbed bedrock or soil at the base. Railway roadbase are prone to a variety of structural challenges that can manifest differently based on their geographical context. In excavated railway sections, particularly those located in limestone regions, the occurrence of karst cracks and cave formations is a significant concern. Such geological phenomena may lead to the ballast stones falling into underlying cavities, thereby diminishing the thickness of the ballast layer. This reduction can adversely affect the bearing capacity of the railway sleepers, thereby compromising safety during train operations. Additionally, during the summer months, ballast may become saturated with rainwater, resulting in the formation of mud and mud overflow to the ground surface; conversely, in winter, the volume of ballast may increase due to ice heaving, leading to deformation of the railway track and square cement sleepers. Both scenarios pose safety risks for train operations and necessitate a thorough investigation of the ballast structure with ground penetrating radar.

To assess the condition of the raiway ballast structure, a Ground Penetrating Radar (GPR) system, along with three sets of air coupled antennas operating at a center frequency of 1.0 GHz, was employed. The antennas were strategically positioned at the front of the train, elevated 45 cm above the square cement sleepers, and arranged on the left, center, and right sides of the railway track. The GPR system successfully detected the railway cement sleepers and ballast structures, producing a two dimensional longitudinal profile for each antenna. The hyperbolic reflections generated by the cement sleepers were pronounced, which interfered with the emitted signals from the ballast, obscuring the ballast interface. Data processing was performed using a specialized local removal curve algorithm, which utilized a raw profile to subtract the local curve profile of the square cement sleepers, thereby eliminating the influence of the square cement sleepers. This data processing procedure resulted in a continuous reflection signal from the ballast layers, allowing for the identification of water distribution in water-bearing areas, variations in ballast thickness, and the structural characteristics of the railway subgrade and ballast layers in limestone regions. The Ground Penetrating Radar equipped with a horn antenna was utilized for scanning the railway ballast, yielding ballast clear reflection signals when combined with the specialized local removal curve method, thereby enhancing railway safety.

How to cite: Deng, X.: The method to get clear image for the railway ballast structure with the Ground Penetrating Radar Horn Antenna, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-1404, https://doi.org/10.5194/egusphere-egu25-1404, 2025.

As shallow mineral resources continue to deplete, deep mineral exploration has emerged as an essential trend in the mining industry. One of the most direct and effective methods to enhance exploration depth is by increasing the spacing of the current electrode in the array. However, this increase often results in a stronger electromagnetic (EM) coupling effect, which can significantly interfere with the induced polarization (IP) signal. To address these challenges, this paper calculates the EM coupling effects of various measuring arrays in both uniform half-space and layered media using analytical methods. Based on these calculations, we further analyze the impact of various factors on the intensity of EM-coupling interference in the layered media model, including the type of measuring array, the spacing of the current-electrodes, as well as the resistivity and frequency. Ultimately, based on the differences in the phases of the IP and the EM-coupling in the frequency domain, we derive the calculation formula of the relative phase method and analyze its decoupling effect at various application scenarios. The results indicate that an increase in the spacing of the current electrode, a decrease in ground resistivity and an increase in working frequency will significantly enhance the intensity of EM coupling interference. Under consistent conditions and detection depths, the EM coupling interference is typically greater for Schlumberger array compared to pole-dipole array. By employing the relative phase method, the biggest working frequency of the pole-dipole array can be enhanced by a factor of four, while the Schlumberger array can experience an increase of 10 to 11 times. It demonstrates that the relative phase method has a certain effect for removing the EM-coupling in large-depth IP exploration. The research provides significant guidance for the field implementation of large-depth IP exploration.

How to cite: Qin, H., Chen, R., Ji, Z., and Wang, Q.: Electromagnetic coupling analysis and removal in large-depth induced polarization method by using the relative phase, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-1815, https://doi.org/10.5194/egusphere-egu25-1815, 2025.

The definition of apparent resistivity is a critical aspect of in electromagnetic methods, particularly in the context of the electrical source transient electromagnetic method (ESTEM), which has not been well resolved. This study presents a novel concept termed pulse impedance for ESTEM, which is defined as the ratio of the first-order time derivative (pulse response) of the horizontal electric field to the vertical magnetic field. This innovative definition facilitates the derivation of a clear and explicit expression for apparent resistivity that maintains accuracy across the entire range of periods. The pulse impedance approach notably eliminates the source term from the calculations, resulting in an apparent resistivity that is independent of source parameters, thus enhancing the robustness and reliability of the resistivity estimations. The efficacy of this approach was corroborated through the analysis of data obtained from both numerical simulations and field measurements.

How to cite: Chen, W. and Zhu, Y.: Pulse Impedance: A New Approach to Defining Apparent Resistivity of Electrical Source Transient Electromagnetic Data, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-1844, https://doi.org/10.5194/egusphere-egu25-1844, 2025.

Lithology identification is crucial in mineral and energy resource exploration as it determines geological composition and guides exploration activities, improving resource location and evaluation efficiency. The advancement of artificial intelligence technology has promoted the application of machine learning-based multi-source geophysical data fusion methods in lithology identification. However, due to the differences in geophysical exploration techniques and data types across mining areas, single machine learning methods often struggle to adapt to diverse geological environments, lacking necessary universality and robustness, which severely restricts the practical application of intelligent identification technology in actual exploration. To address these limitations, this study introduces a Multi-mode Adaptive Prediction System (MAPS) for lithology identification. MAPS innovatively integrates three learning models (supervised, semi-supervised, and unsupervised learning), and can automatically select the most suitable learning mode based on prior information such as the quantity and quality of existing labeled samples and the completeness of geological background information, achieving rapid and accurate lithology identification. We verified MAPS's performance advantages through extensive comparative experiments: in supervised learning mode, compared to Support Vector Machine (SVM) and Naive Bayes classifier, accuracy improved by 0.7% and 3.5% respectively, with F1 scores increasing by 3.4% and 4.5%; in semi-supervised learning mode, compared to semi-supervised fuzzy C-means algorithm and self-learning algorithm, accuracy and F1 scores improved by a minimum of 33.67% and 0.15 respectively; in unsupervised mode, compared to traditional fuzzy C-means and Gaussian mixture models, MAPS demonstrated superior ability to mine and construct internal data structures, showing stronger feature learning capabilities. Furthermore, MAPS has shown excellent performance in the practical application of coal seam location prediction. The coal seam locations predicted by the system are highly consistent with actual drilling results, further validating MAPS's significant application potential in practical engineering. In conclusion, MAPS significantly improves the efficiency and accuracy of lithology identification, providing reliable technical support for mineral and energy resource exploration with broad application prospects.

How to cite: Lv, P., Xue, G., and Chen, W.: Lithology identification method based on Multi-mode adaptive prediction system: Algorithms and Applications, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-1868, https://doi.org/10.5194/egusphere-egu25-1868, 2025.

We present a comprehensive geophysical methodology that combines magnetotelluric (MT), gravity and/or seismic data in a joint 3-D inversion framework to reduce interpretational uncertainty and provide a more accurate subsurface image of volcanic and geothermal systems. The methodology leverages the complementary sensitivities of each dataset—electromagnetic data for electrical conductivity, gravity for density contrasts, and seismic for velocity variations—to characterize subsurface structures more robustly than any single method alone.

As a demonstration, we apply this integrated workflow to Newberry Volcano in central Oregon, an important target for geothermal development and Enhanced Geothermal System (EGS) research. Broadband MT and gravity data were inverted jointly and integrated with existing seismic models. The integrated inversion/interpretation confirms a prominent conductive feature beneath the volcano’s southern rim and flank (SRFF), which is also marked by low density and slower seismic velocities. This feature extends from the southern caldera floor near the 1,300-year-old Big Obsidian Flow (BOF) to depths beyond 4 km, yet remains disconnected from the sub-caldera magma body.

Through this Newberry Volcano example, we illustrate how a multi-parameter approach provides improved resolution of the subsurface architecture and fluid flow pathways, highlighting the critical role of joint inversion in unraveling complex volcanic systems. The results not only shed light on Newberry’s hydrothermal alteration and fluid pathways but also underscore the broader applicability of our integrated methodology in guiding geothermal exploration and de-risking subsurface resource assessments.

How to cite: Tu, X., Schultz, A., and Di, Q.: Integrated MT, Gravity, and Seismic Inversion and Interpretation for Improved Subsurface Imaging, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2763, https://doi.org/10.5194/egusphere-egu25-2763, 2025.

Thrust fault zones around the Tibetan Plateau (TP) record the tectonic evolution between the Plateau and its surrounding terranes, which is helpful for understanding the uplift mechanism and deformational processes of the TP. The Longmenshan fault (LMSF) is the tectonic boundary (TB) between the Yangtze terrane (YT) and Songpan-Garze terrane (SGT), while the TB of its western segment, either the Lijiang-Xiaojinhe fault (LXF) or Jinhe-Qinghe fault (JQF), is controversial. Therefore, we conducted magnetotelluric (MT) imaging, surface structure surveys, and petrologic analysis to further determine the deep–shallow structural relationship of the western LMSF segment. Resistors R1 and R2 revealed by MT imaging may have originated from different magmatism. Among them, R2 may have originated from plume underplating, which is consistent with previous studies, while R1 may have originated from the residue of episodic mafic magma intrusion along the JQF over a broader period. Based on regional geophysics, surface structural patterns and petrologic mineralogy, it is suggested that the JQF may have deformed deep into the lower crust or upper mantle, accommodating the southeast expansion of the TP by thrusting and acting as the TB between the YT and SGT before ~15 Ma. After ~15 Ma, due to the activation of the large-scale strike-slip faults, the LXF gradually replaced the JQF to dominate the structural deformation of the western LMSF segment. Our results indicate that the above tectonic transition might be associated with the geodynamic process from centralized deformation to diffuse deformation within the southeast TP during the late Cenozoic.

How to cite: Qiao, W., Jian, Y., Shibin, X., and Guozhong, L.: Cenozoic tectonic transition within the western segment of theLongmenshan fault, southeast margin of the Tibetan Plateau: Insights fromgeological and geophysical data, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3388, https://doi.org/10.5194/egusphere-egu25-3388, 2025.

In the past decades, electromagnetic (EM) logging while drilling (LWD) has been widely used for well landing and geosteering in high angle and horizontal wells. Recently, this technology has been extended to geo-stopping applications in vertical wells and deviated wells, leveraging its excellent look-ahead-of-bit capability, particularly in ultra-deep reservoirs. Compared to traditional look-around applications in horizontal wells, achieving look-ahead capability is significantly more challenging because the sensitive region of the tool's response is primarily concentrated in the formation between the transmitting and receiving coils. Current look-ahead methods typically use the information from the drilled formation as a constraint to invert the formation ahead of the bit. However, this approach heavily relies on the accuracy of the surrounding formation property measurements. Therefore, to enhance the look-ahead capability and accuracy, it is necessary to further improve the contribution of the formation ahead of the bit to the tool's response.

In this paper, we analyze the spatial sensitivity of the magnetic field components based on the Born geometric factor. Among these, the coaxial (Hzz) and coplanar (Hxx and Hyy) components exhibit look-ahead sensitivity and can be used for look-ahead detection. In EM LWD look-ahead measurements, it is common to combine the coaxial and coplanar components to define the look-ahead signal. We further derive the spatial sensitivity functions for phase shift and amplitude ratio, with results showing that the primary contribution to the look-ahead signal still comes from the formation between the transmitter and receiver. To address this, we propose a signal enhancement method based on Multi-TR-spacing signal superposition. By exploiting the differences in sensitivity ranges of signals from different TR spacings, the method optimizes the sensitive space through signal superposition, thereby improving the tool’s look-ahead performance. Finally, we employ numerical simulation algorithms to compare the look-ahead capability of the new method with traditional methods. Simulation results demonstrate that, the look-ahead signal obtained with the new method is significantly enhanced to 1.5 times, and the maximum distance range has been increased by 30% that enabling the detection of interfaces at greater distances. Additionally, the new method results in a stronger sensitivity to the formation boundaries ahead of the bit, suggesting an improvement in inversion accuracy. It is important to emphasize that the method proposed in this paper can also be extended to look-around detection, for further enhancing the sensitivity of a specific detection area.

How to cite: Liao, X., Wu, Z., and Yue, X.: Sensitivity Analysis and Optimization for Enhancing the Look-Ahead Capability of Electromagnetic Logging While Drilling Tools, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-5673, https://doi.org/10.5194/egusphere-egu25-5673, 2025.

The semi-airborne transient electromagnetic (SATEM) method has attracted increasing attention for its efficiency in various exploration scenarios. A recent geophysical survey in northern Gansu, China, employed the SATEM system to investigate the potential distribution of Volcanogenic Massive Sulfide (VMS) deposits. Several observed data profiles showcase significant late-time negative values, which were attributed to induced polarization (IP) effects associated with VMS minerals, as prior time-domain IP (TDIP) measurements revealed their high polarizability characteristic in such regions. More recently, interest in interpreting TEM data with IP effects has notably increased in the geophysical community as these effects can significantly disturb the data, leading to misinterpretation using the conventional resistivity-only (RO) inversion approach. Guided by the Cole-Cole model, which quantitatively describes the IP effect of materials using DC resistivity and other three IP parameters, numerous previous inversion studies have been successfully conducted to extract multiparametric information.

In this work, one field data profile is demonstrated in Figure. 1a and was inverted using a quasi-2D hybrid constrained inversion algorithm including three terms: (1). The classical data misfit functional; (2). Laterally smoothing regularization; (3). Fuzzy c-means (FCM) clustering regularization, which can facilitate the integration of the prior geophysical information. Local geological investigations suggest that VMS targets are primarily deposited in intact fracture spaces, which offer favorable conditions for mineralization and storage. The inversion results, shown in Figure. 1b, display clearly high-to-moderate resistivity interfaces surrounded by distinct IP value distributions. Moreover, the extending high IP distribution toward the deep is supposed to result from mineral dissemination, resulting in high resistive polarization anomalies and deeper conductive polarization anomalies caused by mineral enrichment. The above characteristics are considered the indicators of VMS minerals in such area.

To sum up, the IP-incorporated inversion facilitates the interpretation of TEM data collected over high polarization areas. However, the serious ill-pondness issue of multiparametric inversion brings a great challenge to result reliability, which largely depends on the selection of the starting model and inversion scheme. Integrating the geological and geophysical information in the inversion offers a promising way to avoid misinterpretation

How to cite: Lu, J., Wang, X., Guo, M., and Xue, S.: Application of the semi-airborne transient electromagnetic method over the VMS deposit and data interpretation incorporating induced polarization effects, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7917, https://doi.org/10.5194/egusphere-egu25-7917, 2025.

The induced polarization (IP) parameters, such as the peak relaxation time and polarizability, have the potential to characterize pore structures of geomaterials and can be further used to distinguish lithology. However, the systematic experimental research on the IP response of carbonate rocks is scarce. To fill this gap of knowledge, we investigated the complex resistivity of 16 carbonate rocks, including dolostone and limestone, and discussed the applicability of existing induced polarization mechanisms for carbonate rocks. The relationship between IP parameters and pore structures were further analyzed by the experiment on variable confining pressure. The results indicate that the carbonate rocks with intergranular micropores or microfractures exhibit observable induced polarization response, where the amplitude and phase of complex resistivity are frequency-dependent, and still exist under high pressure conditions. Dolostone is characterized by low resistivity, high peak relaxation time, low polarizability, and the bell-shaped phase spectrum. Moreover, Stern layer polarization can explain the positive correlation relationship between peak relaxation time and pore size in samples with intercrystalline micropores. In contrast, membrane polarization provides a mechanism for the larger peak relaxation time in samples with microfractures, which is related to the low pore aspect ratio.

How to cite: Ma, M., Zhao, J., Yan, B., Zhang, Y., Sun, Y., and Ouyang, F.: Experimental Study on the Induced Polarization of Carbonate Rocks, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-8112, https://doi.org/10.5194/egusphere-egu25-8112, 2025.

The study and characterization of caves is a complex problem because not all underground cavities are accessible and therefore cannot be characterized by direct methods, such as topographical or geomatic methods. Therefore, geophysical surveys play a key role, as they can provide information on the size and shape of underground cavities from surface measurements.

In this work, two underground cavities characterized by different geological contexts and located in eastern Sicily (Italy) were studied: i) the “Micio Conti Lava tube”, a lava cave located in the municipality of San Gregorio di Catania and ii) the “Chiusazza Cave”, a complex karst cave located in the area of Syracuse. The two caves were investigated using both DC resistivity surveys and direct methods for 3D reconstruction (terrestrial laser scanner (TLS) and photogrammetry by unmanned aerial vehicle (UAV)).

In the “Micio Conti Lava tube”, N. 11 ERT (electrical resistivity tomography) profiles and N. 18 TLS stations were performed, while in the “Chiusazza cave”, N. 11 ERT profiles and N. 23 TLS stations were implemented.

In both cases, aerophotogrammetry was used to generate the 3D models of the epigeal environments. Geoelectrical surveys were performed using the dipole-dipole quadripolar configuration and a cluster analysis (K-means) was performed on the 3D resistivity models of both caves. This analysis revealed for each site two groups of clusters, highlighting areas with different resistivity values. A comparison between the resistivity models and the clusters showed a good overlap between the clusters identified in the central portion of the two models and the areas characterized by the highest resistivity values. This approach allowed the identification of isosurfaces for both areas that enclose the areas associated with the shape, position and size of the investigated cavities. In the "Micio Conti Lava Tube" area, the cavity is characterized by resistivity values higher than 17000 Ω-m while, in the Chiusazza cave area, the cavity is identified by resistivity values higher than 4000 Ω-m.

Comparing the results obtained by resistivity and 3D TLS models, an excellent correspondence can be observed for the "Micio Conti lava tube". Instead, for the "Chiusazza Cave", the models do not seem to fit perfectly in the central portion, probably due to the limited coverage of geoelectrical surveys in this area due to the prohibitive logistic conditions of the site.

This study confirms that DC resistivity methods are suitable for identifying and characterizing underground cavities in different geological contexts. Cluster analysis allowed to identify the isosurface value to be assigned as the boundary of the area of ​​the studied cavities. The results of this study clearly show that by integrating geophysical and 3D survey techniques, it is possible to increase the mapping and understanding capabilities of these geological structures, even if they are inaccessible from the surface.

How to cite: Morreale, G., Grassi, S., Messina, D., Monforte, P., Giudice, G., Quattrocchi, G., and Imposa, S.: DC resistivity surveys compared to direct 3D surveys methods to characterize underground cavities in eastern Sicily (Italy), EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-8531, https://doi.org/10.5194/egusphere-egu25-8531, 2025.

In ocean-continent transition zones at rifted continental margins, distinguishing between crustal rocks, hydrated mantle rocks, and the boundary between continental and oceanic mantle is crucial. These materials exhibit distinct resistivity characteristics, making them identifiable through geophysical techniques. Marine Controlled-Source Electromagnetic (CSEM) surveys are particularly effective in mapping subsurface structures both onshore and offshore due to their sensitivity to conductivity contrasts.

Our study focuses on using multiple geophysical techniques to investigate crustal and mantle rocks at magma-poor rifted margins. We focus on the continent-ocean transition at the Goban Spur, located southwest of the UK. Here, previous seismic work suggested the presence of a broad zone of exhumed serpentinised mantle, in between continental crust confirmed by drilling and oceanic crust represented by the prominent linear seafloor spreading magnetic anomaly 34. We deployed 49 seafloor instruments on a c. 200 km transect spanning these three basement types, coincident with a pre-existing high-quality seismic reflection profile, to collect seismic, magnetotelluric (MT), and controlled-source electromagnetic data.

For navigation, the CSEM system integrated USBL positioning, CTD measurements, and an altimeter. The transmitter utilized a compact waveform with a fundamental frequency of 0.25 Hz, enhanced by maximizing the amplitude of the 3rd and 7th harmonics. The transmitter dipole moment was 30,000 A·m, powered by a current of 100 A.

For data analysis, the compact waveform was processed in short 4-second time windows. We do stack the 4-second FFT up to 60 seconds or longer.  This approach retained essential information while enhancing the signal-to-noise ratio, enabling robust time-series analysis.

CSEM and MT methods have shown promise in resolving debates about lithospheric structure. While these techniques have previously imaged fluid-rich zones in subduction settings, this study is the first to apply them to continent-ocean transitions in rifted margins. We present results from preliminary analysis of both CSEM and MT datasets, focusing on lateral changes in resistivity at the seaward limit of continental crust.

How to cite: Li, Y., Ivey, K., Constable, S., Minshull, T., and Bayrakci, G.: An electromagnetic investigation of the continent-ocean transition southwest of the UK., EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-8667, https://doi.org/10.5194/egusphere-egu25-8667, 2025.

Geophysical techniques are an efficient method for identifying hidden hazards in embankment dams due to the presence of significant physical differences in dam hazards. However, there is still a lack of sufficient understanding of the coupling relationship between different geophysical fields of different hazards, which hinders the detection accuracy of geophysical methods. By combining the theories of seepage field, stable electric field, electromagnetic wave field, and elastic wave field, a multi-physics coupling equation and boundary conditions for the hidden hazard model of embankment dams are established. Based on different geophysical methods, the geophysical responses of dam models with different water levels, hazard types, and sizes were modeled and used as the library of training samples. These samples were thoroughly trained using the YOLO convolutional network model, and training metrics like recall, accuracy, and loss curve were used to assess the quality. The results indicate that the GPR and seismic images are more accurate in identifying the hazard of the cavity, ant nest, and fracture, whereas the ERT is more successful in identifying the leakage risks. In addition, the location of the submerged surface can be accurately determined by the ERT, which is more sensitive to the water level.

This work was funded by the Science and Technology Project of Jiangxi Province (2022SKLS04, 2023KSG01008) and the National Natural Science Foundation of China (42374097)

How to cite: Yu, H., Hu, S., He, S., Chen, H., Deng, J., and Wang, S.: 3-D modeling of coupled geophysical fields for hidden hazards in the embankment dam using YOLO convolutional network model, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14126, https://doi.org/10.5194/egusphere-egu25-14126, 2025.

Based on the mechanism of current density formation under natural electric fields and artificial stable current sources, this study proposes a multi-physics coupling theory involving seepage fields, ion diffusion fields, and stable electric fields induced by leakage. Coupling equations and boundary conditions for electric and magnetic fields were formulated based on fundamental laws of Ohm’s law and Biot–Savart law. A finite element-infinite element numerical simulation method was used to achieve three-dimensional response characteristics of coupled electric and magnetic fields in embankment leakage scenarios by incorporating conversion relationships for the water content, resistivity, and ion concentration. Based on the distribution characteristics of coupled electric and magnetic fields, a detection technique for locating leakage channels in embankment dam was proposed. This technique enhances leakage channel signals by applying an artificial stable electric field on both upstream and downstream sides of the channel. Subsequently, precise localization of leakage risks is achieved by observing two components of the coupled electric field or three components of the magnetic field on the dam surface. This new method was applied to locate the leakage channel at a pond in Hangzhou. The detection results have been validated by the drilling results, which demonstrated that this technique offers higher precision and better detection performance compared to traditional high-density resistivity methods. This work validate the effectiveness of the coupled electric and magnetic field-based detection method and provide a novel solution for embankment leakage detection.

How to cite: Liu, S., Chen, H., Deng, J., He, S., Wang, S., and Chen, Y.: Research on localization technology for dam leakage channels based on coupled electric and magnetic fields, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14405, https://doi.org/10.5194/egusphere-egu25-14405, 2025.

Post-mining can raise environmental issues, including water contamination in tailings storage facilities. Contaminated mine drainage can occur in these facilities when oxygen and water come into contact with tailings containing sulfides. In the past 20 years, various reclamation methods have proven to be effective in preventing potential contamination, such as the use of multi-layer cover systems. These engineered covers consist of successive layers with different hydrogeological properties to prevent water from reaching tailings. One way of assessing the effectiveness of these covers on the field is to monitor the flow of water within the cover over time, using time lapse electrical resistivity tomography (TL-ERT) in conjunction with hydrogeological instruments. This method allows to recover the spatio-temporal distribution of the soil electrical conductivity, and thus providing an image of the water flow in the near subsurface.

The objective of this project is to monitor water flow within a mine cover system which acts as a barrier to water infiltration into tailings using TL-ERT. This approach involves the use of numerical models, combined with field and laboratory data processing.

This study presents preliminary results from the two-weeks field campaign that was conducted in Fall 2024 at a tailing storage facility in Quebec where a multi-layer cover system is installed on a 7% slope. The cover configuration consists of four layers: 30 cm of silt, 20 cm of gravel, 30 cm of moisture-retaining silt, and 20 cm of gravel as a capillary break (from top to bottom). A 32 m-long ERT profile was installed along the slope of this cover with 64 electrodes and a spacing of 0.5 m. A 20 cm-high, 30 cm-wide and 2.75 m-long trench was excavated perpendicularly to the ERT profile, one-third along the profile. An infiltration test was performed, during which a total of 2000 L of a 1000 μS/cm saline tracer was injected into the trench over a period of 4 hours. TL-ERT monitoring consisted of acquiring a dataset of 65 ERT images using the Wenner configuration, every hour during the infiltration test, and every 6 hours thereafter for a week.

Preliminary results from field data inversion showed a spatio-temporal variation in resistivity associated with the start of the infiltration test. Near the trench, the inverted conductivity increased by a factor of two soon after the start of the injection, and a slightly conductive bulb appeared along the slope in the hours following the test. In addition, over the course of the two-week recording period, the surface of the cover became increasingly resistive, which can be associated to a significant drop in temperature between the beginning and end of the monitoring period (no rain was monitored during the monitoring period). The future steps of the processing will include a temperature correction to ensure that resistivity variations are only attributed to water inflow. Finally, thermo-hydrogeological modeling of the multilayer cover system during the infiltration test will allow to compare the geophysical results with modeled water dynamics.

How to cite: Bedoui, L., Dimech, A., Boulanger-Martel, V., Bussière, B., Sylvain, K., Impinna, T., and Plante, B.: Field study on the application of time-lapse electrical resistivity tomography to assess the performance of an inclined multi-layer cover system reducing water infiltration, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14411, https://doi.org/10.5194/egusphere-egu25-14411, 2025.

With the intensifying exploration and development of deep and unconventional oil and gas reservoirs, the advanced prediction of the formations during drilling plays a pivotal role in mitigating drilling risks and optimizing drilling parameters. This technique serves as a crucial foundation for enhancing drilling trajectory accuracy and reducing operational costs. Currently, ultra-long spacing and low-frequency technologies enable the look-ahead, ultra-deep electromagnetic (EM) logging-while-drilling (LWD) tool to detect the top of the target formation more than 30 meters ahead of the bit. However, the measurement signal is predominantly influenced by the stratigraphy surrounding the instrument, resulting in a very low proportion of the spatial contribution in front of the bit. Consequently, the inversion process, which is integral to look-ahead detection, poses challenges for real-time geosteering.

To tackle this challenge, this study introduces a novel multi-spacing interleaved compensating antenna design aimed at augmenting the electromagnetic scattering field signal share at the forward stratigraphic interface. The spatial distribution of the new look-ahead detection signal is characterized using geometric factor theory. Additionally, the response characteristics and look-ahead detection capability of the proposed scheme are simulated and analyzed based on a response fast forwarding algorithm. The integral geometry factor associated with the novel look-ahead measurement effectively excludes contributions from the stratigraphy in the vicinity of the instrument, thereby enhancing the proportion of the look-ahead signal. This advancement is particularly beneficial for look-ahead detection. Simulations based on a single interface model reveal that the response diminishes to zero when the instrument is positioned at a considerable distance from the interface, whereas it attains non-zero values as the tool approaches the interface. In addition, the polarity of the response depends on the difference in resistivity between the two sides of the interface, which offers a more intuitive interpretation compared to existing methodologies. Furthermore, variations in magnetic field attenuation across different spacings leveraged to optimize spacing and signal synthesis combinations, further bolstering the capability of look-ahead detection. Numerical results demonstrate that the new method significantly improves the look-ahead detection capability of phase difference measurements compared to existing methods, with a maximum look-ahead depth of detection (DOD) increased by approximately 50%. The look-ahead DOD of amplitude ratio signal is comparable to that of existing methods.

In summary, the proposed method provides a more intuitive response to resistivity anomalies ahead of the bit, reducing the update time for forward geostructural information and enabling improved look-ahead detection. This innovation will provide a more cost-effective drilling solution for proactive risk avoidance in straight or low-angle wells and optimize casing shoe placement and coring operations.

How to cite: Wang, Y., Wang, L., Fan, Y., Ge, X., Yue, X., and Liu, T.: A New Compensated Design of Deep-reading Look-ahead Method in Electromagnetic Logging-while-drilling, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14438, https://doi.org/10.5194/egusphere-egu25-14438, 2025.

The rapid growth of the oil and gas industry, driven by the increasing demand for fossil fuels, has led to significant environmental challenges. Among these, hydrocarbon pollution around refineries has emerged as a critical issue that was largely overlooked until recent decades. Romania, a prominent player in the petroleum sector, continues to rely on substantial reserves for fuel production. However, the environmental consequences of refining and transporting petroleum products were historically ignored, leading to widespread soil and groundwater contamination.This study focuses on the Petromidia Navodari Refinery, one of Romania’s most important refineries, and investigates the extent and impact of underground hydrocarbon pollution. To achieve this, geophysical methods such as electrometry and Ground Penetrating Radar (GPR) were employed alongside soil drilling for sample analysis. The investigation covered several zones, each spanning 400 to 600 square meters, and extended over several kilometers surrounding the refinery. Measurements reached depths of up to four meters, encompassing the water table—a critical layer for environmental and public health.

Electrometric data revealed high resistivity values at depths of 0.5 to 3 meters, indicating the presence of hydrocarbons, which impede electrical conductivity. These findings align with the depth of the groundwater table, highlighting the risk of pollutant transport through underground water systems to populated areas. GPR surveys identified anomalies at depths of 1 to 2.5 meters, corresponding to zones affected by hydrocarbon infiltration. The integration of GPR and electrometric data with soil sample analyses confirmed hydrocarbon contamination in these layers.

Using these datasets, a detailed map was created to illustrate the spread of underground pollution, revealing both the affected area and the dynamic movement of contaminants. Additional mapping of groundwater flow patterns allowed for the estimation of the speed and direction of hydrocarbon migration, enabling predictions of the contamination’s future expansion.

This research underscores the significant environmental impact of petroleum processing and transport, particularly the contamination of soil and aquifers. Such pollution poses severe risks to public health, agriculture, and ecosystems. By identifying the affected zones and quantifying the extent of contamination, this study provides valuable insights for mitigation strategies.

The findings emphasize the urgent need for stricter environmental policies and remediation measures around refineries. These should include monitoring systems, improved waste management practices, and technologies for reducing hydrocarbon emissions into the environment. The integration of geophysical techniques such as electrometry and GPR proves to be an effective approach for assessing and managing underground pollution.

In conclusion, the study highlights the critical importance of addressing refinery-related pollution through comprehensive assessments and informed interventions. By providing a scientific basis for action, this research supports efforts to mitigate the environmental and public health impacts of the oil and gas industry.

How to cite: Dragos, A. G., Anghel, S., Iordache, G., Baraitareanu, B., and Dudu, A.-C.: Geophysical Studies of Electrometry and GPR for Mapping Underground Pollution Spread Around the Petromidia Navodari Refinery, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-19846, https://doi.org/10.5194/egusphere-egu25-19846, 2025.

Mine tailings storage is a major challenge for the mining industry due to the risks associated with contaminated mine drainage. Tailings can contain sulfides that, when exposed to atmospheric oxygen and precipitation, generate acidity that can spread downstream from tailings storage facilities. To mitigate this issue, the construction of multi-layer cover systems designed to divert infiltrating water from the tailings represents a promising solution. However, such cover systems are susceptible to deteriorate over time, and their effectiveness must therefore be regularly assessed.

Unlike traditional destructive methods, non-invasive geophysical techniques offer a rapid and cost-effective solution for analysing these cover systems. However, each geophysical technique has its own limitations when used individually. In particular, the ERT-IP (Electrical Resistivity Tomography and Induced Polarization) and MASW (Multi-channel Analysis of Surface Waves) methods can be used to characterize the volumetric properties of soils, such as variations in electrical resistivity and seismic velocities, but often lack the precision to delineate fine interfaces clearly. GPR (Ground Penetrating Radar) and seismic refraction, on the other hand, offer a better resolution for identifying the boundaries between layers but have difficulty in accurately describing the physical properties in volume.

This project aims to demonstrate the potential of a multimethod approach that combines these techniques by jointly analyzing the results to leverage their respective advantages while overcoming individual limitations and biases. Ultimately, the goal is to develop a joint inversion methodology to further refine the imaging of multi-layer cover systems, which are generally shallow and are made from a large range of materials.

This study presents the results from a field campaign conducted on a tailings storage facility where inclined multi-layer cover systems have been constructed to limit water infiltration (~1 m thick). Two longitudinal profiles were analyzed at two different scales. A high-resolution profile (32 m-long, 7% slope), with 64 collocated geophones and electrodes spaced by 50 cm intervals was used to focus on fine-scale variations in the cover layer system. Measurements were taken before, during, and after an infiltration test. A longer profile (100 m-long), with 64 collocated geophones and electrodes spaced by 1 m covered two instrumented sections (a 7% slope and a 28% slope) to provide a larger-scale view and greater depth of investigation. The ERT-IP data (collected using the Wenner protocol) and seismic data were coupled with GPR profiles conducted in continuous mode using 200 MHz and 1500 MHz antennas. All geophysical datasets were surveyed to allow comparison between techniques.

The results are interpreted jointly, in order to exploit the interface detection capabilities of GPR and refraction techniques along with the volumetric characterization provided by ERT and MASW at two different scales, which could improve the applicability of geophysical methods to assess the in situ performance of multi-layer cover systems installed on tailings storage facilities across larger scales.

How to cite: Impinna, T., Dimech, A., Fabien-Ouellet, G., Bussiere, B., Bedoui, L., and Boulanger-Martel, V.: Geophysical Multimethod Joint Analysis for Assessing Multi-Layer Covers on Mine Tailings at Two Different Scales, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20337, https://doi.org/10.5194/egusphere-egu25-20337, 2025.

Sewage Treatment Plants (STPs) are essential infrastructure for addressing climate change, preserving aquatic ecosystems, and enabling sustainable energy transitions. Traditionally focused on meeting regulatory standards by removing pollutants, modern STPs have transformed into multifaceted systems capable of tackling environmental challenges through resource recovery, energy generation, and emissions reduction. This evolution positions STPs as integral components of the circular economy and broader climate action strategies. Untreated wastewater is rich in organic matter, which decomposes and releases greenhouse gases, primarily methane (CH₄) and nitrous oxide (N₂O), with emissions ranging between 75–175 CO₂eq/m³ and approximately 0.625 kg/m³ of solid dry waste. By efficiently separating and processing organic matter, STPs can reduce these emissions by about 35% and solid dry waste by nearly 70%. Advanced sludge treatment technologies, such as anaerobic digestion and gasification, enhance STP efficiency by enabling resource recovery and energy generation. Adopting energy system modelling and assessment frameworks can significantly improve the operational and environmental performance of STPs. These tools comprehensively evaluate energy flows, emissions, and resource recovery processes, offering insights into system retrofitting and renewable energy integration. Such analysis also reveals opportunities for producing renewable energy sources, including biogas and syngas, which can be processed into hydrogen, a clean energy carrier with significant potential for decarbonizing energy systems. Reforming these gases to produce hydrogen reduces reliance on fossil fuels and supports a net-zero emissions framework. Scenario modelling enables stakeholders to assess the impacts of policy interventions, renewable energy synergies, and small-scale energy generation technologies. Additionally, STPs contribute to nutrient recycling by recovering essential elements like nitrogen and phosphorus from wastewater, reducing dependence on energy-intensive synthetic fertilizers and their associated greenhouse gas emissions. Advanced technologies like sludge-to-fertilizer conversion or biochar production further reinforce the circular economy by generating valuable outputs from waste streams. The study reveals that incorporating advanced sludge treatment technologies and hydrogen production pathways can reduce greenhouse gas emissions by up to 98% and solid waste by approximately 95%. Furthermore, these systems have the potential to produce 2.2 g/m³ of hydrogen and 54.3 g/m³ of methane from syngas and biogas, respectively. Through this holistic approach, STPs can drive progress toward achieving circular economy objectives and addressing the urgent challenges of climate change.

How to cite: Vidyarthi, P. K., Arora, P., and Blond, N.: GHG emission reduction and energy production through sewage treatment plants, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-808, https://doi.org/10.5194/egusphere-egu25-808, 2025.

The anticipated expansion of photovoltaic (PV) energy production is likely to have major impacts on ecosystems globally. PV arrays alter the spatiotemporal availability of abiotic drivers, such as light and precipitation, creating discrete microenvironments. Plant responses to PV-induced environmental heterogeneity are increasingly well studied, suggesting spatially explicit patterns of phenology, photosynthesis, productivity, and community composition; however, potential differences in soil microbial processes across these microenvironments are relatively unknown.

To determine how PV arrays influence soil microbial processes, we leveraged an established single-axis tracking photovoltaic array in Colorado, United States, where agriculture and PV energy production are co-located. We conducted our experiment in a portion of the array dominated by a C3 grass (Bromus inermis) to investigate soil physiochemical properties, microbial community structure, and function across microclimates. Soil samples were collected during the growing season from each panel edge (i.e., east & west), beneath panels, between panels, and outside of the array. Soil physiochemical properties generally did not differ across microclimates, although organic matter was highest on the east panel edge, where aboveground productivity is consistently greatest. Soil microbial biomass C & N were highest beneath panels, while substrate induced respiration rates were highest on the east panel edge. Soil microbial community structure differed greatly between microclimates within the array and plots outside the array, with unique bacterial & fungal genera dominating each microclimate (e.g., the fungi, Xylaria, on the east panel edge). Hence, the presence of PV arrays will generate microclimates that alter soil microbial community structure and function in grassland ecosystems, potentially shifting carbon cycling and other ecosystem processes.

How to cite: Siggers, J. A., Sturchio, M., Smith, M., and Knapp, A.: Environmental heterogeneity imposed by photovoltaic array alters grassland soil processes, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-1130, https://doi.org/10.5194/egusphere-egu25-1130, 2025.

Embedding sustainability into industrial practices has become an essential strategy for addressing environmental, economic, and social challenges in manufacturing and consumption. This approach ensures that products meet current demands without compromising the ability of future generations to satisfy their own needs. Our previous study introduced a novel four-step methodology for sustainable product lifecycle management, utilizing multi-objective life cycle optimization. By enhancing the understanding of trade-offs between different sustainability objectives, this methodology enables a comprehensive evaluation of various product design alternatives at the early design stage, considering material selection, manufacturing processes, usage scenarios, and end-of-life strategies. Building on prior research, an advanced multi-objective optimization framework has been developed to support sustainable strategy decision-making. The proposed methodology provides decision-makers with data-driven recommendations through four key steps: (1) identifying potential sustainability strategies, (2) conducting a cost-benefit analysis of these strategies, (3) formulating an optimization model for sustainable decision-making, and (4) solving the optimization problem using the weighted sum method. Sustainability strategies are systematically evaluated across four key life cycle assessment (LCA) stages: material selection, manufacturing processes, usage phase, and end-of-life treatment. Cost-benefit analysis is performed based on initial costs and return on investment (ROI), incorporating economic, environmental, and social dimensions. Environmental and social ROI are assessed using life cycle impact assessment indicators such as global warming potential and eco-toxicity. The optimization model can be tailored to different organizational contexts by adjusting system boundaries, strategy constraints, and objective functions to align with corporate sustainability goals or the United Nations’ Sustainable Development Goals (SDGs). Implementation of this methodology is currently underway in an industrial case study, with results and discussion forthcoming. By providing a structured and quantitative framework, this research aims to facilitate the integration of sustainability into strategic decision-making and policy development. The approach is expected to serve as a foundation for more advanced models of sustainable strategy decision-making across various sectors, with potential extensions to broader social impact considerations. Furthermore, by offering a quantitative basis for sustainability strategies, this study supports evidence-based policymaking and contributes to the advancement of sustainable product design and manufacturing practices.

How to cite: Huang, Y. and Tung, C.-P.: A Multi-Objective Optimization Methodology for Enhanced Sustainable Strategy Decision-Making: A Life Cycle Assessment Perspective, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2992, https://doi.org/10.5194/egusphere-egu25-2992, 2025.

The enhanced resolution of about 300 m in along-track direction that have satellite synthetic aperture radar altimetry missions —  CryoSat-2, Sentinel-3A/B  and Sentinel-6MF — reprocessed with the advanced SAMOSA+ retracker enables more precise wave power density estimations in coastal zones, where wave energy converters are typically deployed.

This investigation is conducted using high-resolution altimetry data from an EC-OCRE-EO database created in the frame of the Horizon 2020 program. In different coastal regions we investigate the influence of ocean currents in modifying the magnitude of the wave power density, which for regions characterized by strong currents could be a crucial information to extract abundant quantity of the wave resource to be transformed in clean energy. We perform along-track comparisons to find the correlation between wind, waves and ocean current and its relationship with the wave power density.

This study, conducted as part of ESA's ongoing WAPOSAL project (https://eo4society.esa.int/projects/waposal/), investigates the wave energy potential with CryoSat-2 and Sentinel-3A/B reprocessed data in regions of strategic importance for renewable energy exploration.

How to cite: Ponce de León, S., Orejarena, A., Panfilova, M., Restano, M., Sabia, R., and Benveniste, J.:  Influence of ocean currents on the Wave Energy Potential inferred from  High-Resolution Satellite Altimetry - preliminary results, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3711, https://doi.org/10.5194/egusphere-egu25-3711, 2025.

In Germany, about 23% of the total final energy is consumed for the heat supply (space heating and warm water) of residential buildings (as of 2022) (UBA 2024a, 2024b). Approximately three million older medium-sized multi-family houses with 3 to 12 residential units are responsible for a significant portion of CO₂ emissions in the building sector. To achieve climate goals, the number of renovations would need to increase from the current approximately 4.1 million to 13–16 million buildings by 2045. The dynOpt-San project (BMWK, 2024) supports the achievement of these goals by developing standardized renovation concepts and efficiently integrating innovative photovoltaic-thermal systems in combination with phase-change material storages (PVT-PCM systems). Additionally, a self-learning energy management system with integrated operational monitoring is being developed to optimize and monitor the operation of multi-family houses and districts.

In this contribution, we showcase a prototypical version of such energy management system as well as cloud-based monitoring tools, and we present initial results and lessons learned from first real demonstrator buildings. The predictive energy management relies on a two-level architecture to coordinate energy flows at both the building and district levels with minimal effort. To model the energy system components, we utilize the open-source python framework oemof to formulate mixed-integer linear problems. To facilitate predictive optimization, we incorporate information about future electricity prices, weather forecasts, as well as energy consumption forecasts on residential level, generated with machine learning approaches. The objectives of the energy management system include reducing costs and CO₂ emissions, achieving an optimal self-consumption rate within the buildings, and promoting grid-friendly behavior of the district.

BMWK (2024):  Project dynOpt-San:  Digital unterstützte und modulare Sanierung von Mehrfamilienhäusern in Quartieren mit PVT-PCM-Wärmepumpensystemen und selbstlernendem Energiemanagement, 1/2024 – 12/2026, funded by German Federal Ministry BMWK, funding code 03EN6024A-G, https://www.dynopt-san.de/, last accessed: January 13, 2025

UBA (2024a), Energieverbrauch privater Haushalte, https://www.umweltbundesamt.de/daten/private-haushalte-konsum/wohnen/energieverbrauch-privater-haushalte, last accessed: January 7, 2025

UBA (2024b), Endenergieverbrauch nach Energieträgern und Sektoren, https://www.umweltbundesamt.de/daten/energie/energieverbrauch-nach-energietraegern-sektoren, last accessed: January 7, 2025

How to cite: Wunsch, A., Wallner, S., Hörter, T., and Bernard, T.: Predictive Two-Level Energy Management for the Energetic Optimization of Multi-Family Houses and Districts, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-5485, https://doi.org/10.5194/egusphere-egu25-5485, 2025.

Multi-energy systems (MESs) integrate a variety of technologies and energy carriers into a unified framework, offering flexible and efficient solutions to the challenges of modern energy systems. These include the urgent need for decarbonization, greater integration of renewable energy sources, and a push for decentralization and energy market independence. However, long-term planning for MESs is becoming increasingly complex in a rapidly changing world, where socio-economic, technological, and climatic shifts can quickly render obsolete solution previously considered optimal. These challenges are particularly acute for vulnerable systems, such as those in small, isolated island communities.

This study focuses on identifying robust future configurations for the energy-water systems of Italian minor islands, which face significant challenges in energy and water supply. The aim is to increase energy independence and promote decarbonization. The analysis explores the integration of desalination plants and rooftop photovoltaic systems as replacements for fossil fuel generators and water transport via tanker ships, together with the expansion of the islands’ water storage capacity. The study incorporates various sources of uncertainty—technological, climatic, and economic—into a multi-objective analysis to evaluate their individual and combined impacts on optimized configurations.

A novel optimization framework is presented, which combines Multi-Objective Evolutionary Algorithms (MOEAs) with the multi-energy system planning model CALLIOPE. This approach identifies trade-off solutions for energy-water system configurations under conflicting objectives. The process is iterated across several scenarios, each defined by a unique combination of uncertainties. Sensitivity indexes and probabilistic analyses are employed to assess variations in performance metrics and the robustness of optimized configurations to each uncertainty source.

The results reveal that the optimal configurations include substantial integration of photovoltaic systems and desalination plants, effectively reducing CO₂ emissions and energy costs. The analysis also highlights the significant role of uncertainty in influencing system performance, particularly the impact of technology-specific parameters like ship tanker emission factors. and desalination plants efficiency. In most scenarios, especially for the island further away from the coast, the replacement installation of desalination plants coupled with renewable technologies proves to be both cost-effective and environmentally sustainable, demonstrating the robustness of the proposed configurations.

This work provides a new decision-making tool for multi-energy system planning, which emphasise the critical role of uncertainty analysis in ensuring resilient planning under fluctuating resource availability and demand. It explores multiple options for the implementation of renewable energy solutions in isolated and vulnerable regions, contributing to a sustainable and resilient energy transition.

How to cite: Tangi, M. and Amaranto, A.: Multi-objective Optimization and Uncertainty Analysis Reveal Resilient Water-Energy System Configurations on Small Islands, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-10757, https://doi.org/10.5194/egusphere-egu25-10757, 2025.

The transition to a bioeconomy aims to reduce dependence on finite fossil resources, mitigate climate change, and promote sustainable development. Forest biomass plays a key role in the bioeconomy, contributing significantly to bio-based materials and energy production. The transition to the bioeconomy implies the acceleration and upscaling of biomass production and use. However, increasing demand for forest biomass may drive substantial changes in land use and forest management, resulting in environmental impacts, such as, alterations in carbon balances.

Despite the growing emphasis on the bioeconomy, studies quantifying spatially and temporally explicit environmental impacts of increased forest biomass demand are limited. Existing assessments use aggregated and static models, which overlook spatiotemporal variations in land-use, land-management, and environmental outcomes. Addressing this gap is critical to quantify impacts of bio-based systems along value chains and to understand the trade-offs associated with increased woody biomass demand for bio-based products. Accounting for spatial and temporal variation of environmental impacts of the biobased economy requires an integrated modelling approach which includes economic modelling, land-use change and land management change simulation, environmental impact analysis, and approaches to allocate impacts outcomes to bio-based products.

This study aims to quantify the spatial and temporal variation in environmental impacts of bio-based products, driven by land-use and land-management changes resulting from increased forestry biomass feedstock demand in Europe up to 2050. By addressing impacts at both the land level and the bio-based product level, the study provides a comprehensive evaluation of the trade-offs associated with forest biomass sourcing, filling critical gaps in existing assessments. This research adopts an ex-ante and spatiotemporally explicit approach to assess these impacts, focusing on the impacts on carbon balances. More specifically, the approach consists of the following steps:

• Biomass-demand scenarios development using a partial equilibrium forestry economic model: Scenarios of biomass demand for bio-based materials, energy, and other applications. These scenarios, disaggregated by biomass types, form the basis for analysing future land-use changes and linking impacts to bio-based products.
• Spatio-temporal land-use change modelling with the partial equilibrium forestry economic model: Projections of land-use allocation across land use types (e.g., cropland, managed forests, and natural vegetation) while capturing competition among sectors.
• Carbon balance modelling with a forest resource allocation model: Simulation of the impacts of afforestation, deforestation, and forest management practices on carbon emissions and removals under alternative and standard forest management practices.
• Allocating biomass supply to demand with a spatially-explicit techno-economic model: Biomass-demand scenarios outputs are downscaled to a spatially-explicit techno-economic model for bio-based product-level allocation, allocating biomass supply to demand. This step helps making the link of environmental impacts to specific bio-based products.

The results offer an integrated framework to quantify spatial and temporal variations in environmental impacts of bio-based products. By focusing on product-level impacts and spatiotemporal variations, this research supports sustainable forest biomass sourcing strategies, identifies trade-offs, and informs evidence-based policymaking to align bioeconomic growth with long-term environmental sustainability goals.

How to cite: Rondon Villabona, M. A., Duden, A., and van der Hilst, F.: Environmental impacts of increased biomass demand for bio-based products in the bioeconomy, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13261, https://doi.org/10.5194/egusphere-egu25-13261, 2025.

Clean hydrogen will play an indispensable role in decarbonizing “hard-to-abate” sectors. However, it is not a “one-size-fits-all” solution because clean hydrogen production currently entails low energy efficiency, high costs, limited supply and risks of leakage.  U.S. policy efforts to date have focused on the supply of clean hydrogen.  However, prioritizing demand applications that maximize environmental and economic benefits is critical. Here we evaluate clean hydrogen’s decarbonization potential in a variety of energy-intensive sectors in the U.S. circa 2035.  We identify oil refining, ammonia production, and steelmaking as “no-regret” sectors, whereas on-road transport and trains fall into the “do-not-use” category. We compare the implications of policymakers GHG mitigation objectives and stakeholder profit maximizing objectives and find that current supply-side subsidies are insufficient to ensure optimal clean hydrogen allocation. Sector-specific demand-side policies are required to align priorities of policymakers and stakeholders to maximize the potential benefits of clean hydrogen.

How to cite: Mauzerall, D., Wu, Y., Atouife, M., Cheng, F., Luo, Q., Perera, A., and Jenkins, J.: Prioritizing demand-side applications for clean hydrogen to maximize environmental and economic benefits, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13911, https://doi.org/10.5194/egusphere-egu25-13911, 2025.

Integrated assessment model simulations are often cited when recommending  carbon capture and storage (CCS) as an important component of decarbonization for the power industry. Here, we use a simplified setting to analyze the economic sensitivity of post-combustion fossil-fuel CCS to a set of parameters including fuel costs, electricity prices, and subsidies. We formulate the model to represent coal and natural gas power plants fitted with CCS. We then ask what level of subsidies are necessary to make CCS profitable for the operator. Our results indicate that: (1) With current US subsidies and under most market conditions, CCS is much more profitable when injected carbon dioxide is used for enhanced oil recovery than for geologic storage. For this reason, CCS is likely to continue to be used for enhanced oil recovery and so will increase system-wide emissions because the combustion of the oil produced emits more carbon dioxide than is injected to produce the oil. (2) CCS subsidies can drop the marginal cost of electricity generation to near zero, making CCS fossil fuel electricity competitive with renewables in the power market, even as these power plants continue to emit a portion of their carbon dioxide. (3) With CCS subsidies, coal-fired power production can become more profitable than natural gas power because coal produces more carbon dioxide and hence harvests more subsidies. To be profitable, natural gas power plants require higher tax subsidies than coal, and their cash flow is more sensitive to changes in the price of power, which disadvantages natural gas plants when coupled to CCS. (4) In the US, subsidies are provided per ton of carbon dioxide stored rather than per ton of carbon dioxide kept out of the atmosphere. Our calculations demonstrate how the effective subsidy per ton of emissions avoided is more than the subsidy paid per ton of carbon dioxide captured unless the grid is completely decarbonized, because of the energy penalty of CCS. (5) The value of natural gas CCS for reducing emissions diminishes as the carbon intensity of the local power grid increases. We recommend that these insights be used in integrated assessment models such that these models more accurately represent the influence of market dynamics and provide better insights for reducing emissions. 

How to cite: Biçe, K., Gulden, L., and Harvey, C.: Post-combustion fossil-fuel CCS in the US: impact of market and policy dynamics, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14628, https://doi.org/10.5194/egusphere-egu25-14628, 2025.

Background: The need to address the dual challenges of climate change and biodiversity loss is pressing and requires collective efforts in both land-use and energy sectors. However, the interactive impacts between mitigation and biodiversity conservation measures, especially the indirect impacts through the energy-land nexus, have not been comprehensively investigated. The question arises as to whether and what levels of synergies or trade-offs exist between mitigation and biodiversity targets, and what are the implications on energy system decarbonization pathways and corresponding mitigation costs.

Methodology: By applying and comparing two modelling frameworks that link integrated assessment models (AIM, MESSAGEix-GLOBIOM) and biodiversity models (Figure 1), we explore the system-wide synergies and trade-offs between the ambitious climate and biodiversity targets included in the Paris Agreement and Kunming-Montreal Global Biodiversity Framework (KMGBF). Four forward-looking policy scenarios with different mitigation and biodiversity conservation ambitions are simulated for the period 2010-2070 to quantify the land-use dynamics, greenhouse gas emissions, biodiversity indicators, as well as energy transformation pathways under different policy targets. Additional sensitivity analysis and decomposition analysis allow us to explore the implications of alternative mitigation pathways on the key findings, and to disentangle the effects of individual policy measures within the mitigation and biodiversity portfolios.

Results: Scenario results show that despite biodiversity synergies from stringent mitigation measures for the 1.5°C target, area-based biodiversity conservation measures are not enough to revert the declining trends of biodiversity. Biodiversity losses can be halted or decelerated with combined mitigation and biodiversity efforts, but until 2070 global biodiversity cannot restore its 2010 levels. On the other hand, due to the energy-land nexus, deploying biodiversity conservation measures can double the carbon price in line with the 1.5°C target and increase global gross domestic product loss by 0.7% by 2070. However, the availability of alternative negative emission technologies and increased pasture production efficiency can act as enablers to reduce the additional costs to achieve 1.5°C-mitigation induced by the biodiversity target. Besides, the large land demand for co-achieving stringent mitigation and biodiversity targets can increase the global average price of agricultural products by 35-53% in 2070 and reduce food consumption. Avoiding the potential negative implications on food security would entail substantial food system transformation efforts. Our results indicate that the challenges of co-achieving the 1.5°C and KMGBF targets can be amplified via cross-sectoral impacts on the energy system and be greater than previously thought. This calls for more careful policy design to simultaneously address the two targets while limiting the trade-offs with food security or the economic feasibility of decarbonization.

Figure 1. Overview of research design

How to cite: Wu, Y., Frank, S., Tsuchiya, K., Leclère, D., Fricko, O., Fujimori, S., Gusti, M., Hasegawa, T., Lessa Derci Augustynczik, A., Krisztin, T., Rouet-Pollakis, S., Wögerer, M., van Meijl, H., van Zeist, W.-J., Hirata, A., Krey, V., Ohashi, H., Takahashi, K., Riahi, K., and Havlík, P.: Challenges and enablers of co-achieving ambitious global climate and biodiversity targets, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14971, https://doi.org/10.5194/egusphere-egu25-14971, 2025.

The future of the Canadian federal carbon tax is uncertain due to a lack of public and political support, as well as an upcoming federal election. The relationship between the carbon tax and the effectiveness of other decarbonization policies is currently unquantified, whether it be synergistic or antagonistic. Prioritization of the highest impact alternative decarbonizaiton policies could aid in long-term strategy under political uncertainty. We employ the recently released MESSAGE-Canada integrated assessment model to explore decarbonization pathways wiith and without the carbon tax. For both future scenarios, a Morris sensitivity analysis of the 33 currently announced Canadian decarbonization policies will be conducted. Changes in the ranking of impact are assessed for key federal-level system indicators, such as cost and emissions. Further, policy impacts rankings on provincial metrics are also compared by scenario for major energy production and consumption provinces. Lastly, the samples generated are also used to develop a range of feasible pathway projections that better capturing Canada’s decarbonization trajectory under uncertainty. Comparing the ranking of policy impacts indicates the extent to which the carbon tax acts synergistically with other policies to reduce emissions, and thus is the most crucial lever for reaching decarbonization targets. However, this ranking also allows us to prioritize exploration of the next most effective policies in the absence of the tax. 

How to cite: Judson, M., Awais, M., and McPherson, M.: Impactful Canadian decarbonization policies in times of an uncertain carbon tax, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-15302, https://doi.org/10.5194/egusphere-egu25-15302, 2025.

World and Europe’s climate emergency and renewable electricity production are a central topic for present and future energy security and carbon emission strategies, requiring strong efforts to governments and industries for their achieving.

Diversification in the mix of sources providing electricity is getting more crucial day after day. Among the many possibilities, offshore generation has seen an outstanding increase in the last twenty years, in particular in those areas where wind, solar and wave data performance enables to reach high capacity factors and where landuse is a sensitive topic for protected onshore areas and biodiversity, especially for the islands.

In particular, floating generation in the last few years has dragged the attention of investors and governments for its potential and positive implications, from technical, economic and employment perspectives. Floating Offshore Wind Farms (FOWF), after years of studies and prototypes, are now an actual feasibile source, showing tens of projects under development and approval phases in the Mediterranean areas and in the Nordic regions, showing their great potential. Furthermore, the coupling of these technologies with other energy generation forms, like solar photovoltaic and wave kinds, and storages, as electrochemical and hydrogen ones, could contribute to reach a more complete, stable and economically efficient system.

In this context, Iceland’s energy systems relies on about 70% out of its total electricity generation from hydroelectric plants, followed by almost 30% from geothermal source, and less than 1% from wind, solar and fossil-fuel production. Moreover, it is the European country with the highest share of renewables in final energy consumption, scoring a value around 82%. Nevertheless, grid shortages, blackouts, houses not connected to the national grid, peaks of demand from energy-intensive factories, unpredicable events, force the use of carbon-based fuels to cope with lacks of electricity, mainly diesel ones. This requires an improvement in the variety of sources of generation and storage, aiming at a 100% renewable scenario. Focus of this work is to analyze the Icelandic energy mix and investigate the possibility of implementation of offshore electricity generation and storages, and the expected effects on this energy self-sufficient island. Furthermore, the study considers the environmental impacts and the grade of public acceptance towards these technologies. Eventually, a comparison with the Mediterranea island of Malta provides more completeness to the research work.

How to cite: Cappellari, M., Lorenzoni, A., Finger, D. C., and Guðlaugsson, B.: Offshore electricity generation potential and its integration into the energy system of an energy self-sufficient island: a case study of Iceland, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-16495, https://doi.org/10.5194/egusphere-egu25-16495, 2025.

The growing demand for green energy triggered the development of innovative technologies, such as energy harvesters. Energy harvesters can harness and convert ambient kinetic energy into electric energy. The harnessed energy can be utilised to power small monitoring devices within water networks, particularly in remote or off-grid locations. Integrating energy harvesters within water systems offers a promising opportunity to enhance network monitoring, thereby improving resilience and reducing the risk of system failures. However, successful deployment requires a complex understanding of the technical, economic, and social risks involved.

This research, conducted as a part of the H-Hope Horizon project (https://h-hope.eu/), synthesises insights from seven case studies through semi-structured interviews with key stakeholders involved in each case, including industry professionals, policymakers and researchers. The aim is to identify and analyse the enablers and challenges associated with implementing energy harvesters. Relevant stakeholders were identified through the snowball sampling method. To understand the dynamics, this research employs two methods: the Driving forces, Pressures, State, Impact, Response (DPSIR) and Causal Loop Diagrams (CLDs). The DPSIR model categorises and evaluates the various risks by identifying the driving forces, pressures, current system conditions, impacts and necessary responses. CLDs are used to visualise the interconnections between factors and to highlight enablers and barriers to deploying energy harvesters within water networks.

The results reveal that providing a power supply to remote sensors for enhanced monitoring is a key enabler for water and energy systems. Enhanced monitoring is widely perceived as reducing the risk of failures across most systems, thereby increasing the resilience of the water networks. In cases where energy harvesters enable successful monitoring, the benefits generally outweigh most other concerns. Specifically, providing power to sensors in remote locations has been identified as a significant opportunity for improving water network operations. The main barriers identified are related to pipe diameter compatibility, maintenance requirements and the risk of mechanical obstructions, all of which can increase the likelihood of system failure and complicate maintenance. Additionally, conflicting institutional interests between owners and operators pose further barriers to deploying energy harvesters within water networks.

Overall, stakeholders emphasise the transformative potential of energy harvesters to unlock energy savings, reduce operational costs and enhance resilience in water networks. This abstract underscores the importance of a multidisciplinary approach to risk assessment, integrating stakeholder feedback to guide the design, policy development and operational strategies. Addressing these risks is essential to ensure that the energy harvesting technologies in water networks can achieve their full potential, advancing sustainable water-energy solutions on a global scale.

How to cite: Stepanovic, I., Garcia-Santos, G., Guðlaugsson, B., and Finger, D. C.: Assessing enablers and challenges for the deployment of energy harvesters in water networks through stakeholder interviews, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-18505, https://doi.org/10.5194/egusphere-egu25-18505, 2025.

A significant barrier to the planning and installation of large solar power plants is the reduction of arable farmland and the potential despoiling of areas of outstanding natural beauty in the countryside with solar PV panels. Bi-facial Photovoltaics (PV) allow continuing use of land for farming whilst providing an additional income to farmers from royalties associated with solar power production. The ESA GTIF (Green Transition Information Factory) programme initiated three kickstarter projects in 2024 following a successful demonstrator over Austria (gtif.esa.int). The UK-Ireland-France (gtif-uk-ireland-france.net) kickstarter covers 5 different applications (called capabilities) including mapping of PM2.5 at 10m, drought prediction at 10m, urban heat island mapping at 30m and mapping of methane emission plumes at 20m and the mapping of potential areas for the development of solar bi-facial PV (solar bPV) farms over arable and grassland in the 3 aforementioned areas. To select areas of potential development using solar bPV requires knowledge of high resolution spectral albedo, LULC (Land Use Land Cover), topography, and understanding of the solar power equation and Global Horizontal Irradiance (GHI). Spectral albedo is mapped from 10m spectral albedo derived using the ESA HR-Albedo retrieval system [1,2] which was operationalised by the EU Copernicus Sentinel Global Mosaic (https://s2gm.land.copernicus.eu); Global Horizontal Irradiance is taken from both MERRA-2 at 50km and from the UN Solar Atlas at 250m (https://globalsolaratlas.info/map); LULC from the ESA World Cover 2021(https://worldcover2021.esa.int/) and exclusion zones such as Areas of Outstanding Natural Beauty, National Parks and Sites of Special Scientific Interest). Losses due to PV, distance to grid and different seasonal changes are mapped and will be demonstrated for GB and Ireland. The GTIF-UKIF project is now being rolled out across France with the potential to be rolled out across Europe and Africa.

Cited references
[1] Muller, J-P., Song, R., Francis, A.N., Gobron, N., Peng, J., Torbick, N., 2022. Assessment of 10m spectral and broadband surface albedo products from Sentinel-2 and MODIS data. DOI: 10.5194/egusphere-egu22-12092 
[2] Muller J.P., Song R. Brockley D., Whillock M., 2023. Sentinel-2 Global Mosaic HR-Albedo Algorithm Theoretical Basis Document S2GM-UCL-ATBD-v3.1 https://s2gm.land.copernicus.eu/help/documentation

How to cite: Muller, J.-P., Song, R., and Griffiths, P.: Bi-facial PV solar power systems for mixed use of arable and grassland, an evaluation over GB and Ireland taking into account environmental exclusion areas., EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-18951, https://doi.org/10.5194/egusphere-egu25-18951, 2025.

Hydrogen is emerging as a clean energy carrier with the potential to replace conventional fuels, necessitating the development of robust infrastructure for its safe transport and storage. This study examines the impact of hydrogen exposure on the mechanical properties of three polymeric materials polyamide nylon, high-density polyethylene (HDPE), and polytetrafluoroethylene (PTFE) under moderate conditions (20°C, 10 bar, 24 hours). Mechanical properties such as strength, ductility, toughness, and stiffness were assessed through tensile and bending tests on exposed and unexposed samples to evaluate material compatibility in 100% hydrogen environments.

Polyamide Nylon exhibited marginal increases in maximum force and tensile stress at maximum force, with significant improvements in tensile strain at maximum force (+42.42%) and at break (+38.65%), indicating enhanced ductility and toughness. Bending tests revealed a slight increase in flexural stress (+5.18%) and minor reductions in displacement (-5.73%) and modulus (-1.16%). However, the elastic modulus decreased significantly (-14.53%), indicating reduced stiffness. These results suggest nylon’s suitability for applications requiring flexibility and energy absorption, though its decreased rigidity may limit its utility in high-stiffness scenarios.

HDPE showed slight reductions in maximum force and tensile stress (~5%) following hydrogen exposure but demonstrated substantial improvements in tensile strain at break (+124.02%), as well as moderate gains in force (+7.90%) and stress (+7.79%) at break. The elastic modulus decreased by 9.87%, indicating enhanced flexibility but reduced stiffness. In bending tests, HDPE experienced decreased flexural strength (-7.71%) and displacement (-2.40%) alongside a slight increase in stiffness (+4.62%). These findings highlight HDPE’s improved ductility and toughness, making it suitable for flexible hydrogen distribution systems. However, its reduced strength and stiffness may necessitate reinforcement for high-load applications.

PTFE experienced minor reductions in tensile strength and stress at break (~3–5.8%) and a significant decrease in elastic modulus (-40.64%), reflecting considerable softening. However, tensile strain at maximum force increased by 22.12%, indicating improved flexibility. Bending tests showed increases in flexural strength (+16.18%) and stiffness (+39.39%), though displacement at maximum flexural stress slightly declined (-6.98%). These results suggest PTFE’s suitability for applications requiring high flexibility and resistance to bending loads but limited utility in load-bearing roles due to its reduced stiffness and strength.

Hydrogen exposure under moderate conditions enhances ductility and toughness across nylon, HDPE, and PTFE while reducing stiffness. Nylon and HDPE demonstrated minimal strength degradation, making them viable for flexible hydrogen transport systems. PTFE’s significant stiffness reduction may restrict its use to non-structural applications. These findings contribute critical insights into material selection for hydrogen infrastructure. Further research under varying pressures, temperatures, and durations is recommended to ensure the long-term reliability of these polymers in real-world applications, advancing hydrogen-based energy systems.

How to cite: Ahmed, T., Finger, D. C., Narayanan, J. A., Guðlaugsson, B., Varghese, R. T., Hmaimid, Z., and Costa, D. A.: Experimental Assessment of Polymeric Materials for 100% Hydrogen Transportation and Distribution, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20040, https://doi.org/10.5194/egusphere-egu25-20040, 2025.

Air source heat pumps are one of the most promising solutions for decarbonising domestic heating in the UK. However, the extent of their decarbonisation potential is dependent on a number of factors. This study aims to explore the greenhouse gas reduction capabilities of a  heat pump uptake, in the houses currently using gas boilers for specific local authorities. Three different regions in England and Wales were chosen for this study: South Wales, North East England and South England. Furthermore, within each of these regions, at least one predominantly urban local authority was selected. This is to account for the difference in housing characteristics such as floor area. Therefore, local authorities selected were Powys, Cardiff, Vale of Glamorgan, Newcastle upon Tyne, Northumberland, Reading West Berkshire.

In this study, three different house models, including terraced, semi-detached and detached were created within each local authority for calculating heat demand and % reduction in carbon emissions. The annual heating demand for each local authority was then estimated using modelling techniques, alongside temporal, housing and heat flow data. For households with natural gas boilers, the annual greenhouse gas emissions were calculated using typical boiler efficiency (84%). For households with heat pumps, the annual carbon emissions were computed using regional carbon intensity data.

The heating load for the year 2022 (in GWh) for local authorities was calculated as 210 for West Berkshire, 180 for Reading, 680 for Northumberland, 410 for Newcastle, 170 for Powys, 230 for Vale of Glamorgan, and 450 for Cardiff. Seasonal performance factor was observed in close range of 2.3 for all the local authorities in the same year. Finally, the carbon emissions reduction for replacement of 5% of boilers with heat pumps was noted to vary from 2.2 to 2.6% for all the local authorities.

Furthermore, this study revealed that the Carbon Reduction of a local authority was linearly related to the overall heating demand in that local authority, which is an expected result. When considering the base model conditions, the biggest factors influencing the heating demand between different local authority were the number of houses, the split of houses (between detached, semi-detached and terraced) and the average outside temperature. The local authority which performed best on both metrics mentioned was Northumberland, which had many of the prior factors working in its favour. However, it was also determined that other strategies should be implemented to reduce heating demand, alongside the deployment of heat pumps, such as insulation or demand side reduction.

The preliminary results for this work were obtained as part of the ‘Barocaloric materials for zero carbon heat pumps’ project funded by the Engineering and Physical Sciences Research Council (EP/V042262/1).

How to cite: Mehta, N., Burges, W., Hehar, R., Fender, T., and Radcliffe, J.: Evaluating carbon emissions reduction due to the uptake of heat pumps, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20257, https://doi.org/10.5194/egusphere-egu25-20257, 2025.

Energy transition is essential to halt the rise in global temperature. However, energy system may step into a new era of resource dependence, for instance on land, biomass, water and metal. Neglecting resource constraints may compromise the quickly ramp-up of renewables that are required by strict climate targets. Hence, it is vital to adapt cross-system way when conducting energy system planning. In this work, we put forward a framework that can merge industrial ecology tool and optimization model into energy system planning. The dynamic material flow analysis tool is used to quantify the metal requirement in energy scenario, while the linear programming model is used to optimize the energy pathways considering metal availability. We prove the effectiveness of this framework by assessing the metal constraints under China’s large-scale development of wind-power and PV. The results show that: (1) Overall metal requirement of China’s wind-power and PV sector is around 1 billion tons up to 2060, while recycling could conserve 20% of primary metal demand. (2) Copper, Nickel, Dysprosium, Tellurium, Zinc and silver could constraints the development of China’s wind-power and PV. (3) Adjusting the pathways to “first slow then fast” can eliminate the cumulative demand of Ag, Cu, Dy by 15%, 8% and 3% respectively. We highlight that the energy-metal nexus relationship should be treated as an endogenous module in the integrated assessment model. The side effect of increasing metal demand due to energy transition should be assessed in the future to decarbonize the metal supply process.

How to cite: Ren, K., Tang, X., and Höök, M.: Merging industrial ecology tool and optimization model into energy system planning- A case study of assessing metal constraints under China’s large-scale development of wind-power and PV, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-282, https://doi.org/10.5194/egusphere-egu25-282, 2025.

In the global push to address climate change, bulk materials play a critical role due to their significant energy use and CO₂ emissions. While supply-side strategies are emphasized, they are also frequently criticized for unrealistic techno-optimism. Hence, there is increasing recognition, supported by authoritative sources including IPCC reports, that demand-side strategies are equally essential. Demand-side strategies—including more intensive use, extended lifetimes, material-efficient design, and optimized end-of-life processes—offer promising pathways to decarbonize bulk materials by reducing consumption without compromising quality of life. Additionally, demand-side exert systemic impacts on supply chains, investment trends, production costs, and broader environmental factors such as land use, water resources, and pollution. Therefore, an integrated assessment of the direct and indirect impacts of demand-side strategies, as well as the synergies between demand- and supply-side approaches, is crucial for developing effective decarbonization pathways.

Integrated Assessment Models (IAMs) are well-established tools for evaluating the systemic impacts of decarbonization strategies. While traditional IAMs offer detailed representations of supply-side technologies, their demand forecasts—especially for material demand—are often based on socio-economic assumptions and historical data. This sector-specific, isolated approach for material demand projections could result in inconsistent, detail-lacking forecasts that may violate conservation of matter. Addressing these limitations requires a unified framework for demand forecasts that ensures sectoral consistency and aligns with harmonized assumptions, thereby accurately capturing material flows driven by social demand.

Figure 1 Conceptual framework of coupled model

In this study, we couple dynamic Material Flow Analysis (MFA) with the Global Change Analysis Model (GCAM) to enhance material demand forecasts. We use steel as the representative bulk material due to its significant energy use, emissions, and strong links to key end-use demands affected by demand-side strategies. As illustrated in Figure 1, the coupled modeling approach begins with harmonized socio-economic assumptions, such as population and social wealth, ensuring consistency inside the coupled model. Using historical data on in-use product stocks, the model projects future product stocks across sectors including transportation, buildings, machinery, and others. These projected product stocks are then aligned with the end use demand in IAMs, including mobility and housing requirements. The projected product stock translates into future material inflows through stock-driven modeling, lifetime functions, and material intensity factors. Material outflows, including end-of-life scrap, are accounted for as secondary production through recycling processes. The remaining material demand necessary to sustain societal well-being is aligned with the industrial production demand represented in IAMs, while material inflows are dynamically adjusted based on endogenous material prices within the IAM.

This soft linking between IAMs and dynamic MFA establishes a coupled modeling framework to evaluating the systemic impacts of demand-side strategies on bulk materials. Beyond directly reducing product consumption and material production, demand-side strategies can substantially alleviate the burden on supply-side transformations needed to meet emission targets. This, consequently, can shift production roadmaps, reducing both investment and production costs. By integrating demand- and supply-side strategies, this framework offers a cost-effective pathway to decarbonize the bulk material loop and achieve societal emission targets.

How to cite: Song, J., Cao, Z., Dai, H., and Ou, Y.: Evaluating the Systemic Impacts of Demand-Side Strategies on Bulk Materials through Coupled Dynamic Material Flow Analysis and Integrated Assessment Modelling, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-641, https://doi.org/10.5194/egusphere-egu25-641, 2025.

Achieving climate commitments and advancing sustainable development in the Global South hinge critically on the transition to clean energy technologies. This study employs a global framework integrating the Integrated Assessment Model (GCAM) with the air quality model (TM5-FASST) to explore adaptive technological transition pathways for regions lagging in sustainable development. We first examine the impact of regional clean energy policies implemented since the Paris Agreement on the most pressing sustainable development goals in these regions, within the broader context of meeting climate targets. We then propose tailored pathways that enhance synergies between climate action and sustainable development. Our findings reveal that current transition strategies are misaligned with regional SDG priorities. However, region-specific clean energy planning can amplify these synergies—particularly in improving the affordability of clean energy in energy-poor regions, conserving water resources in arid areas, and significantly reducing air pollution and related mortality in highly polluted regions—while also making the technology transition more cost-effective. This study highlights the key trade-offs in existing policies and underscores the urgent need for regionally adaptive strategies to achieve both climate and development goals.

How to cite: Jia, W., Li, D., and Li, J.: Context-specific clean energy transitions for synergizing climate action and sustainable development in the Global South, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-746, https://doi.org/10.5194/egusphere-egu25-746, 2025.

Among the strategies for the low-carbon transformation of building system, the strategy of promoting the transformation of building structure to wooden building has received increasing attention due to reasons such as not reducing the satisfaction of building demands, exerting the carbon sink potential of buildings, and reducing the carbon emissions produced by building materials.

However, in the assessment of wooden building strategy, existing studies rarely consider the impact of wood supply constraints in different regions on the viability of wood buildings, the dynamics of forest carbon sinks under wood supply, the further carbon-reducing effects of wood recycling and diversion to sub-markets, impact of the wood transition in buildings on building performance, and the feedback effects of fluctuating prices of wood and other building materials on building structure change due to changes in production of those materials, which leaves a great deal of uncertainty in the assessment of how much effects the wood building transition strategy can have within the whole life cycle of the building system.

Based on this, this research attempts to establish a bottom-up model (IMED TEC) of the building system with an internal coupling of multi-sector material and energy flows. By doing so, we can simulate the nonlinear influence mechanism among the production of multiple energies and materials, and building services under cost-based decision-making. Furthermore, based on this model, we will attempt to couple it with the GLOBIOM. This will enable us to evaluate the impact of the demand for wooden materials in the building system transformation on global forest carbon sinks and land use. Additionally, we can assess the price of wooden materials under the corresponding supply and further feed this back into the building system model.

Our research will analyze the impacts of building systems transformation across multiple stages and sectors, as well as the dynamics of forest carbon sinks, in order to comprehensively assess the carbon-reducing and other impacts of wood building transformation strategy,

How to cite: Xiao, Y. and Dai, H.: The carbon reduction effect and carbon sink potential of the global wooden building transformation with the multi-sector impacts within the whole life cycle, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2983, https://doi.org/10.5194/egusphere-egu25-2983, 2025.

Many economies set climate mitigation targets for 2020 at the 2009 15th Conference of the Parties conference of the United Nations Framework Convention on Climate Change in Copenhagen. Yet no retrospective review of the implementation and actual mitigation associated with these targets has materialized. Here we track the national CO₂ emissions from both territory and consumption (trade adjusted) perspectives to assess socioeconomic factors affecting changes in emissions. Among the 34 countries analysed, 12 failed to meet their targets (among them Portugal, Spain and Japan) and 7 achieved the target for territorial emissions, albeit with carbon leakage through international trade to meet domestic demand while increasing emissions in other countries. Key factors in meeting targets were intensity reduction of energy and the improvement of the energy mix. However, many countries efforts fell short of their latest nationally determined contributions. Timely tracking and review of mitigation efforts are critical for meeting the Paris Agreement targets.

How to cite: Li, S., Meng, J., Hubacek, K., Eskander, S., Li, Y., Chen, P., and Guan, D.: Revisiting Copenhagen climate mitigation targets, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3269, https://doi.org/10.5194/egusphere-egu25-3269, 2025.

Increasing climate urgency mandates accelerating the phasing out of fossil fuels. The energy transition needs materials and mobilizing materials needs energy. Consequently, building the succeeding renewable energy infrastructure faster will require to significantly upscale material supply chains, increasing energy demand and associated environmental impacts. Depending on from where, how fast, and how much materials are mobilized, transition pathways can develop very differently when constrained by the dynamic material availability. Traditionally, energy transition models do not endogenously include the induced material demand and neglect material supply constraints; however, for accelerated transitions dynamic material supply constraints may become defining. This contribution presents essential elements of modeling this feedback loop, applying industrial ecology principles to transition modelling. The presentation will show results on the example of how Aluminum constrains ambitious transition pathways and develops effective strategies for reducing supply constraints and thus accelerating the transition.

How to cite: Desing, H.: Modelling material-energy feedback loops in fast energy transitions, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4524, https://doi.org/10.5194/egusphere-egu25-4524, 2025.

How to cite: Song, W.: A new scenario framework for low carbon transition pathway research: multi-level matrix architecture, narratives, and implications, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4727, https://doi.org/10.5194/egusphere-egu25-4727, 2025.

Climate scenario results are increasingly being used by a wide range of stakeholders outside traditional climate policymaking, such as bankers assessing ESG disclosures or companies planning sustainability strategies. However, the broad, global, and generalized nature of these scenarios often leads to misinterpretation or misuse, highlighting the importance of high-resolution, sector-specific representation for more practical applications.

Based on the technology-rich process modeling of the Integrated Assessment Model (IAM) MESSAGEix-GLOBIOM, we present the updated version with high-resolution endogenized demand sectors (MESSAGEix-GLOBIOM_2.0_BMT, where B represents Building, M for Material, and T for Transport) that will be able to: i) capture energy and material flows through the full supply chain across regions; ii) apply scenarios with sector-level policies/standards that target upstream and downstream emissions or resource use; iii) reveal final energy consumptions induced by demand changes (including demand-side mitigation options such as behavioral changes); iv) identify the role of recycling in the decarbonization transition.

IAMs have relied heavily on input from Life Cycle Assessment to refine their process modeling. With such inputs (e.g., sources and regional flows of raw materials), additionally we were able to spotlight the material and energy embedded in energy and non-energy capacities/infrastructures in the full picture that an IAM can provide. The scenario result set will be more relevant to sector-level policymakers and stakeholders, as it shows how the technology shift of one sector occurs within a system supported by all capacities, infrastructure, and investment along the supply chain, rather than presenting a simplified dynamic as if this sector evolved in isolation.

How to cite: Ju, Y., Van Ruijven, B., and Kishimoto, P.: Extraction to End-Use: Revisiting the Representation of a Dynamic Full Supply Chain with High-Resolution Endogenized Demand Sectors, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-6537, https://doi.org/10.5194/egusphere-egu25-6537, 2025.

Industrial production is built on machinery and equipment capital, which comprises the vast range of tools essential to many industries. As automation and robotics accelerate, service sectors also rely more on machinery. Meanwhile, the shift toward sustainable energy systems and circular economies highlights the importance of machinery that includes wind turbines, batteries, and waste-sorting robots. Using input–output analysis, we found that one-third of the world’s metal production is used for machinery and equipment, contributing to 5% of global greenhouse gas emissions. Our empirical analysis has examined the material and carbon footprints of machinery capital, yet we still lack a clear understanding of how much machinery will be needed in the future and the resulting material and carbon implications. Important demand drivers are the industrialization of developing countries, which today exhibit much lower machinery stocks than industrialized countries, beginning automation in the service sectors, and the needs of the energy transition.

In the pursuit of a climate-neutral society, machinery production merits careful attention due to its dual role. While it serves as a key enabler of technological transitions, producing and operating machinery can also result in significant environmental impacts.

To address these concerns, we developed a scenario-based model that explores machinery’s future material and carbon impacts, supported by the Circular Economy Modelling for Climate Change Mitigation (CircoMod) project. This approach provides a common framework for integrating existing Integrated Assessment Models (IAMs) with NTNU’s forward-looking multi-regional input–output (MRIO) scenarios, EXIOFUTURE. Our work applies existing shared socio-economic pathway (SSP) scenarios and a CircoMod baseline, integrating transformative change and capital dynamics in the industrial sector. Through this modeling, we aim to better identify circular economy and climate mitigation solutions for society’s most significant uses of metals, machinery, and equipment, and to build stronger material demand scenarios. Although still in the early stages, our findings shed light on how machinery production might evolve to support a more sustainable and climate-neutral future.

How to cite: Hertwich, E., Jiang, M., Liu, Y., Della Bella, S., and Wood, R.: Representing material stocks and flows for machinery and equipment in scenario models capturing circular economy and resource efficiency opportunities, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-6952, https://doi.org/10.5194/egusphere-egu25-6952, 2025.

The adoption of a uniform carbon price within and across nations is widely regarded as the most efficient pricing mechanism. However, discrepancies between regional preferences for carbon price levels and the mandated uniform carbon price can lead to households in some regions bearing a disproportionate carbon burden. In this study, we developed an expanded Multi-Regional Input-Output model, newly parameterizing seven key types of power generation within the power sector, and linked it to the Global Change Assessment Model for China (GCAM-China) to identify regionally unequal residential carbon burdens. We employed an empirical approach based on actual carbon prices between countries to determine the carbon pricing preferred by each province under a national carbon emission constraint in the GCAM-China model. The results indicate that between 2030 and 2050, 47% to 87% of provinces will experience carbon burdens exceeding their anticipated levels due to the uniform carbon pricing mechanism, even in provinces where preferred carbon prices are higher than the unified rate. The analysis reveals that while carbon revenue recycling is effective in mitigating these inequitable outcomes, relying solely on the benefits accrued by provinces from the uniform carbon pricing mechanism for transfer payments is insufficient. This study provides insights into regional inequalities in carbon pricing mechanisms for both China and the global community.

How to cite: Yin, Z. and Lu, X.: The Unintended Equity Costs of a Nationally Uniform Carbon Price, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7784, https://doi.org/10.5194/egusphere-egu25-7784, 2025.

Building construction and use are major drivers of climate change. To avoid these impacts, research is exploring the potential of narrowing material and energy cycles (“narrow” strategies) by reducing floor area per capita. Yet, integrated assessment models (IAM) have mostly overlooked material stocks and flow, service levels, and geospatial location of buildings. Thus, they have only limited capacity in modelling such floor area dynamics which are dependent on urbanization trends and changes in dwelling preferences. Current modelling of narrow strategies in IAMs, where available, is therefore focused on normative targets of overall reduction in floor area per capita without consideration of local building stock limitations. Inspired by recent advances in urban metabolism studies of representing urban form in material and energy flow modelling, we propose an integration of detailed geospatial building and material stock accounts with IAMs. Specifically, we demonstrate how the open-source building stock database EUBUCCO can inform the modelling of narrow strategies in the building sector model MESSAGEix-Buildings by adding subnational detail and urban density parameters. EUBUCCO is the first near-complete 3D model of individual buildings including building footprints, heights, usage types and material content in Europe. The database is a collection of government, volunteered, and satellite-derived data, and missing attribute values are inferred with machine learning. Material content is based on the globally harmonized material intensity database RASMI. MESSAGEix-Buildings is a framework to model the material stocks and flows and energy demand of buildings at national or larger scales in future scenarios. Embedding material flow analysis for stock turnover accounting and energy demand modelling at sectoral level, the framework is soft-linked to the MESSAGEix-GLOBIOM IAM to account for demand and supply sides interactions and greenhouse gas (GHG) emissions under different climate policies. EUBUCCO is integrated in MESSAGEix-Buildings by differentiating building and material stocks, as well as demographic trends and climate, at NUTS2 level and degree of urbanicity. This enables for improved representation of floor area and urban form-related aspects, and their regional distributions. With this geospatially informed IAM module, we can model the effect of regionally differentiated floor area reduction pathways, consider population-trend-dependent urban mining potentials, and effects of reverse urbanization such as revitalization of rural building stocks. Ultimately, this integrated module can inform prioritization of such reuse and reduce strategies for climate change mitigation in the housing sector. 

How to cite: Kopp, M. and Mastrucci, A.: Narrowing cycles but where? Geospatial material and building stocks in IAMs to inform reduce and reuse pathways , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12127, https://doi.org/10.5194/egusphere-egu25-12127, 2025.

The Paris Agreement seeks to combat climate change by limiting global temperature rise to well below 2°C, with aspirations of restricting it to 1.5°C by the end of the century. However, substantial uncertainties persist regarding the pace and direction of energy transitions required to achieve these goals, particularly in reducing fossil fuel dependence and determining the social cost of carbon dioxide (CO2). This study examines the impact of uncertainties in the terrestrial carbon cycle on mitigation strategies and energy transition pathways. Using simulations from 11 models within the TRENDY Model-Intercomparison Project, we incorporated these results into the Hector simple climate model, which is coupled with the Global Change Analysis Model (GCAM), a multisector integrated assessment model. Focusing on scenarios limiting warming to 1.5°C, we evaluated energy trajectories and carbon price projections. Our findings indicate that uncertainties in terrestrial carbon cycle projections significantly influence the pace of global energy transitions. Specifically, the phase-out of unabated coal power generation is projected to occur by 2050 ± 7 years, while the ensemble simulations estimate a carbon price of $170.25 ± 38.84 per tCO2e (2010$) by 2100. These results underscore the critical need to enhance terrestrial carbon cycle representations in integrated assessment models to improve projection reliability. Addressing these uncertainties is essential for guiding effective climate policy, enabling informed decision-making, and supporting the implementation of strategies to meet long-term climate objectives.

How to cite: Chen, M., Qiu, H., Cui, R., Zhao, X., Edwards, M., and Pan, M.: Uncertainty in Terrestrial Carbon Cycle Challenges the Assessment of Energy Transition Pathways, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-14189, https://doi.org/10.5194/egusphere-egu25-14189, 2025.

Steel, cement, and chemical products, which serve as the foundation of economic development and daily life, account for 70% of annual greenhouse gas emissions of global basic material production and 16% of total anthropogenic emissions. Emission reduction is urgently needed to meet climate targets. However, these sectors are considered hard-to-abate: Mitigation options for primary production of material such as hydrogen- and bio-based processes, or carbon capture and storage (CCS) are indispensable, but face challenges such as high costs, often low technological maturity and sometimes limitations in their sustainable potential. This causes substantial uncertainty with respect to their short-term availability and long-term feasibility. Therefore, circular economy (CE) approaches - which reduce primary material demands through measures like material substitution, light-weighting, and recycling - are promising complementary alternatives partially due to their scalability, economic viability, and sometimes potential for early implementation. Moreover, they come with the co-benefit of mitigating other adverse effects of primary material production chains such as water use and pollution. Previous scenario modeling studies have explored material transition opportunities through two main approaches: technological substitution in production processes, and strategies from CE such as improvements in material efficiency and enhanced recycling and reuse. To fully capture these transformation options, as well as their interactions, the two research communities of scenario modeling and industrial ecology have increasingly collaborated in recent years. Here, we present REMIND Materials, an integrated approach that couples the integrated assessment model (IAM) REMIND with a dynamic material flow analysis (MFA) framework. REMIND links a macroeconomic general equilibrium model with a bottom-up engineering-based energy system model.  REMIND Materials adds process-based modeling of steel, cement, and chemical production. The MFA framework, represented by the in-house SIMSON model, captures demand, use, and recycling dynamics, enabling the representation of circular economy (CE) strategies such as recycling, reuse, and material efficiency improvements. This integration provides a comprehensive lifecycle perspective on energy-intensive industry pathways to carbon neutrality, including production process transformations, demand-side mitigation measures, and end-of-life strategies. This facilitates not only to investigate each single strategy’s impacts and potentials, but also to demonstrate the strong synergies and economic interactions between different mitigation options. The holistic approach provides decision-makers with critical insights to shape transition pathways that balance climate goals with economic feasibility.

Figure. REMIND Material Model Framework Overview

How to cite: Zhang, Q., Dürrwächter, J., Hosak, M., Weiss, B., Pehl, M., Chen, W., and Ueckerdt, F.: REMIND Materials: Coupling IAM and MFA to Model Synergies of Circular Economy and Decarbonization of Energy-Intensive Industries, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17254, https://doi.org/10.5194/egusphere-egu25-17254, 2025.

As global wealth and population have grown, the world’s demand for materials has tripled since 1970, raising greenhouse gas (GHG) emissions from material production, extraction and use due to their intensive energy requirements (United Nations Environment Programme, 2024). The circular economy (CE) is considered a novel approach to production and consumption systems that emphasises cyclical, renewable arrangements that extend the life and usefulness of materials and resources (Korhonen et al., 2018), drawing extensively from work undertaken in the Industrial Ecology (IE) field. The transition to a CE is anticipated to have a profound impact on GHG emissions (Khalifa et al., 2022) across various sectors (Cantzler et al., 2020). Given this mitigation potential, calls have been made for Integrated Assessment Models (IAMs) to better integrate modelling of material stocks and flows (Pauliuk et al., 2017), enabling more comprehensive representation of material efficiency and CE strategies (Ünlü et al., 2024). 

However, both IAMs and CE scholars have faced significant criticism for their inadequate consideration of the so-called “Global South”. IAMs have been shown: to be insensitive to developmental needs (van Ruijven et al., 2008); to poorly interpret low-income economic and energy dynamics (Lucas et al., 2015); and to underrepresent Global South participants in scenario and model development (Miguel et al., 2019). Meanwhile, the Global South has been relatively obscured from dominant narratives of CE predicated on corporate leadership, technocratic solutions (Kirchherr et al., 2017) and decoupling growth from environmental impacts (Ghisellini et al., 2016). Global South circularity is shown to be more often necessity- and value-driven, building on bottom-up adaptive community and informal economic practices that respond to limited services and material scarcity (Korsunova et al., 2022; Schröder et al., 2019). Critically, there is now an opportunity within the IAM community to respond to these differing manifestations of circularity as model development is underway, widening the relevance of IAMs to academics and decision-makers operating in the Global South.

In this paper, we aim to understand how process-based IAMs can better integrate the unique contexts and processes of the Global South while developing and extending modelling frameworks to better assess material cycles and CE strategies for climate change mitigation. First, we review the literature on Global South CE for climate change mitigation from which we derive five major modelling challenges for Global South circularity in IAMs, namely scalability, informality, applicability, developmental trade-offs and measurability. Then, we conduct interviews with IAM developers working on CE-related or Global South-based modelling to understand (1) the major factors involved in integrating material stocks and flows into process-based IAMs and (2) how these factors interact with the five aforementioned major challenges for modelling Global South circularity. We combine the insights from both the literature review and expert interviews to suggest improvements for modelling the Global South in IAM-material models from both theoretical and technical perspectives. Overall, our paper contributes actionable recommendations for modellers seeking to redress concerns around the equity and representativeness of climate mitigation models and scenarios and their applicability to diverse socioeconomic contexts.

How to cite: Haswell, F., Edelenbosch, O., Piscicelli, L., Straub, L., and van Vuuren, D.: Global South circularity for climate change mitigation: insights into Integrated Assessment Modelling, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-19348, https://doi.org/10.5194/egusphere-egu25-19348, 2025.

How to cite: Yoffe, H. and Blass, V.: From Lab to Market: Environmental Due Diligence using LCA and IAM tools, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20747, https://doi.org/10.5194/egusphere-egu25-20747, 2025.

Building high-quality reservoir models that integrate geological and petrophysical properties is a complex task. The primary modeling process involves creating two-dimensional maps of porosity and either absolute or effective reservoir permeability using results from well-log interpretations and laboratory measurements of core samples. Often, the petrophysical relationship between rock porosity and permeability is adjusted, and variograms used for spatial correlation are fine-tuned to reconcile with the measurements. However, such adjustments make it challenging to address significant errors in permeability, which can vary dramatically, spanning several orders of magnitude within a geological formation. In energy security and environmental conservation scenarios—such as enhanced oil recovery (EOR), shale gas production, enhanced geothermal systems, and geological CO₂ storage (GCS)—fluid injection typically results in a permeability drop of 35-86% around the injection well. This reduction can impede the injection process and lead to unnecessary remediation costs. Storage capacity, indicated by porosity, and injection efficiency, governed by permeability, are critical criteria for characterizing GCS sites. Therefore, accurate quantification of permeability is essential. Quantitative permeability modeling holds the key to unlocking the questions about fluid flow direction in hydrocarbon reservoirs, especially in the face of limited measurements from core samples or Well tests. Permeability is strongly influenced by pore-scale heterogeneities, which range from nanometers to micrometers (µm), and the evaluation of these heterogeneities varies depending on the scale considered in Euclidean geometry. This study will present a method based on scale-invariant or fractal geometry to predict reliable permeability and will validate these predictions with core-scale measurements. Additionally, the significance of permeability maps in EOR and GCS studies for forecasting fluid flow directions within a reservoir will be examined through two case studies. Finally, the discussion will include future directions for incorporating ultra-small heterogeneous effects (less than 0.1 µm), which are often overlooked due to observational and mathematical-model limitations.

How to cite: Vadapalli, U.: Permeability modeling for Enhancing Resource Utilization, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-210, https://doi.org/10.5194/egusphere-egu25-210, 2025.

The world is striving to achieve net-zero carbon emissions at the earliest possible time. Geothermal energy is one of the renewable energy playing a significant role with its sustainable, consistent and potentially affordable in generating the power and competence in production of green hydrogen. Magnetotellric (MT) method is an excellent way to detect caprock, geothermal fluids and source based on the resistivity models. India’s geothermal resources discloses extensive large number of geothermal provinces with promising energy prospects. However, the present study deals with most promising geothermal province Puga and Chumathag are located in the Indo-Eurasia tectonic collision boundary of NW Himalayan region (altitude ~ 4500m). It is composed of different rock types such as plutonic, basic to ultrabasic, and submarine volcanic rocks (Ophiolites). The Puga valley consists of Precambrian paragneisses, schists, carbonates (Tanglang La) and limestone where as Chumathang region comprises of thick sequence of shallow marine to fluvial deposits of Kuksho formation related to Indus group. A total of 62 MT stations were used in Puga-Chumathang geothermal region to understand the shallow crustal architecture in terms of significant linkage of geothermal fields. The geoelctrical structure derived from the 3D inversion of MT data highlights the different fault structures, lateral extent and upward migration of geothermal fluids at Puga and Chumathang geothermal zones. The study also highlights the presence of secondary magma at a shallow level abducted from Indus Suture zone acts as a possible heat source for these hot springs. 3D MT model along with in observation of negative free air gravity anomaly structural trend signifies the presence of low density material supports the link between both the hot springs. This result greatly helps new pathways in advancing the large-scale plan for geothermal prospecting in India.

How to cite: Pachigolla, V. V. K., Patro, P. K., Azeez, K. K. A., Kadukuntla, C. R., Babu, N., and Mothukuri, S.: Relevance of magnetotelluric method to unlock renewable geothermal energy, A case study from Puga-Chumathang geothermal zone, NW Himalaya, India, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-405, https://doi.org/10.5194/egusphere-egu25-405, 2025.

This study investigates unconventional resources such as coal and shale belonging to the Barakar Formation. Various analytical methods such as fluid invasive low-pressure gas adsorption (LPGA) and mercury intrusion porosimetry (MIP), small angle x-ray scattering (SAXS) and imaging methods were employed to determine the pore attributes and pore characteristics of coal and shale. The results show that coal has an abundance of nanopores that occurs in clusters, having evidence of microfractures in its structure, as observed through scanning electron microscopy (SEM). It was found that the accessible micropore surface area (SA) of coal samples is approximately 2.5 – 3 times that of shale samples, while the accessible and inaccessible mesopore SA in coal is about half of that in shale. Nevertheless, the average pore width of the coal samples is around 0.8 – 0.9 times that of the shale samples. These results suggest that the coal has a higher percentage of organic carbon that contributes to the abundance of organic pores, that leads to higher porosity in coal samples compared to shale samples. The total SA, incorporating the entire spectrum of pore sizes, is about 2 times as large in coal as in shale. Interestingly, despite disparity in pore SA and pore volume, the pore surface roughness in coal is nearly equal to or slightly higher than that of shale. The study provides a detailed analysis of the pore structures of unconventional resources, such as coal and shale from the same reservoir, considering various parameters such as depth, mineralogical  content and surface roughness. During CO₂ gas injection, the coal and shale formations may experience change in geomechanical responses, potentially compromising their mechanical stability. Furthermore, any loss to the caprock integrity could result in leakage and reservoir failure. Thus, this study is critical for estimating the secure CO₂ storage capacity of coal and shale reservoirs. The findings aim to optimize gas adsorption while maintaining structural stability, ensuring the long-term feasibility of CO₂ sequestration in other basins. 

How to cite: Kumar, S., Chandra, D., Vishal, V., and Gamage, R. P.: Multiscale Pore Analysis of Unconventional Resources from the Barakar Formation using Fluid-Invasive,  Scattering and Imaging Methods., EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-977, https://doi.org/10.5194/egusphere-egu25-977, 2025.

In the transition from high CO2-emitting fuel to lower CO2-emitting fuel, natural gas hydrates (NGH) or methane hydrates (MH) provide an opportunity for further development. It is an ice-like solid trapping methane gas within its cage-like structure. It has a high energy density and a higher calorific value compared to coal, with 50% less CO2 emission. The availability of NGH globally is to such an extent that its 10% extraction can suffice the global energy demand for the next ~200 years. 

However, NGH or MH reservoirs come with challenges such as extreme environments, difficult exploration conditions, unpredictable estimation of resources, etc. Though well-explored, the complex geological formations make them very difficult to produce from. The geological matrix of gas hydrates plays a crucial role in their dissociation, strength and mass transfer behaviour. The strength and fluid flow in the hydrate reservoirs is mainly governed by the impermeable layers of fine-grained sediments, which are mud/clay dominant.  

To study the effect of interlayers on the strength of the MH sample, we conducted an experimental procedure that replicates the deep submarine environment. Unlike the conventional cylindrical core sample with homogeneous sediment distribution across the volume, the thin interlayers of fine-grain sediments (clay/mud) were introduced at different height intervals that mimicked the natural lithological conditions. The triaxial stress configurations replicate the real-world submarine environment where MH occurs. After applying confinement pressure, overburden pressure, and lowering the sample temperature to that of a hydrate-bearing zone, gas hydrates formed inside the sediment sample by injecting a mixture of methane and water. After the hydrate formation, the permeability of the sample was measured. Subsequently, the gas hydrate sample was allowed to dissociate, and the drained geomechanical test on the sample was performed. The depressurisation method was used for the dissociation of the hydrates. 

During the experiment, P-S wave velocities were continuously measured. The wave velocities increased between pre and post-hydrate formation and decreased after dissociation. It indicates the enhancement in the strength of the sample due to hydrate formation and reduction due to dissociation. Furthermore, the sample showed compliance as the number of layers or layer thickness increased. The ductile behaviour was observed in the interlayered samples compared to those with non-layered (homogeneous). Moreover, peak strength was reduced by about ~15-20% in the dissociated samples compared with the hydrate-bearing sample. This study resolves the geomechanical behaviour of gas hydrate reservoirs, which is key to developing production strategies.

How to cite: Tulsawadekar, K., Vishal, V., and Gamage, R. P.: The effect of sediment interlayers on the triaxial compressive strength of gas hydrate-bearing sediments, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-1052, https://doi.org/10.5194/egusphere-egu25-1052, 2025.

Mine water in disused flooded coal mines is a potentially valuable low carbon heat source. This mine water must be resilient to the impacts of climate change. Changes in temperature and rainfall could affect mine water resources, but the range of impacts and, crucially, whether they are negative or positive – and how they are developed and operated – have not been researched to date. This research is investigating, for the first time, the impacts of climate change on mine water resources. 

To understand these impacts, we work at two mine water heat prospect case study locations in Central Scotland. We selected one on the east coast and one on the west coast to investigate and account for different rainfall patterns. Since May 2023 we have been undertaking field monitoring and subsequent lab analysis to examine seasonal and longer-term changes. In the field, we analyse mine water levels/recharge, chemistry, temperature, and gases (CO₂ and CH₄). In the lab we test for parameters that could be affected by climate change e.g. conductivity, total dissolved solids; a minimum mine water suite e.g. iron; and a standard suite of anions and cations. Additionally, to expand our geographical and temporal coverage, we are collating secondary data from sources including the Mining Remediation Authority, UK Geoenergy Observatories (UKGEOS), and the Scottish Environmental Protection Agency (SEPA).   

Here, we present (a) an assessment of potential impacts of climate change on mine water, (b) early insights into seasonal variation and potential causes and impacts, (c) emerging implications, and (d) future work. 

How to cite: Gillen, C., Burnside, N., McGrane, S., and Roberts, J.: Investigating the potential impacts of climate change on mine water resources: Central Scotland as a case study., EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-1347, https://doi.org/10.5194/egusphere-egu25-1347, 2025.

Shale reservoirs are recognized for their ability to serve as natural barriers for conventional hydrocarbons and their suitability for CO₂ sequestration, owing to their organic-rich composition and intricate pore structures. This study investigates the shales of the Barakar Formation in the Mand Raigarh Basin, India, to evaluate their potential for CO₂ storage by analyzing factors influencing pore volume and surface area. A comprehensive suite of analytical techniques—XRD analysis, Rock-Eval pyrolysis, and low-pressure gas adsorption using N₂ and CO₂ probes—was employed to assess mineralogy, organic matter content, and pore characteristics. Thermal maturity assessments revealed that the shales are transitioning from immature to marginally mature stages, with kerogen types reflecting a mix of gas-prone and oil-prone organic matter. Mineralogical analysis highlights the predominance of clay minerals, alongside other components influencing shale composition. High-resolution 2D imaging offers a detailed understanding of pore structures, emphasizing the role of organic matter and clay minerals in controlling gas adsorption behaviour. Mesopore development was strongly associated with clay minerals, while organic matter predominantly governed micropore formation. Fractal analysis revealed the complexity of pore morphologies, showing higher irregularity in smaller mesopores than larger ones.  These findings underscore the intricate relationship between mineralogical and organic components in determining the suitability of Barakar Formation shales for CO₂ sequestration. By integrating insights into thermal maturity, organic composition, and pore structure, this study highlights the Barakar Formation shale’s significant potential as a secure and efficient CO₂ storage site, contributing to climate change mitigation, sustainable resource management, and a deeper understanding of shale's role in carbon sequestration. This work contributes to climate change mitigation strategies by leveraging the structural and compositional characteristics of shale formations for carbon management. The results align with global sustainability objectives, transforming shales from traditional energy resources into effective tools for reducing atmospheric CO₂ levels, thereby bridging energy needs with environmental management.

How to cite: Ghosh Dastidar, S., Sarkar, K., Chandra, D., Hazra, B., and Vishal, V.: "Shale Reservoirs as Potential CO₂ Storage Sites: Exploring Mineralogical and Organic Interactions", EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3402, https://doi.org/10.5194/egusphere-egu25-3402, 2025.

Coal is a natural porous medium with a strong adsorption property and is an important energy resource over the world. The strong adsorption property of coal is a causative factor affecting the occurrence of coal and gas outburst. Gas is recognized as the main contributor to the energy release during outburst, and it initiates and maintains the chain process of outburst. Outburst is initiated by the fragmentation and failure of coal, where the adsorption property of coal plays a positive role. Additionally, the pore structure of coal is one of the significant factors affecting the CO₂ sequestration performance. As a widely accepted potential management method for greenhouse gas, CO₂ sequestration in coal seam is affected by the coal-mass properties, seam permeability, and long-term behavior of the sequestrated CO₂. CO₂ adsorption can significantly alter the porous property of coal and affect the CO₂ sequestration capability of coal seams. Both outburst and CO₂ sequestration are subjected to and significantly affected by a long-term sorption process. The former is promoted by the fragmentation of the coal mass induced by adsorption, whereas the latter is threatened by the adsorption-induced fracture. To explore the influence of long-term sorption on the mechanical and porous characteristics of coal, long-term sorption tests were performed. The results indicated that the long-term sorption significantly degraded the mechanical and microporous properties of coal. And, long-term CO₂ adsorption even destroys and pulverizes the coal samples. The findings enhance our understanding of the mechanism underlying the fragmentation of the coal mass during outburst, while may present challenges for CO2 sequestration in coal seam.

How to cite: Zheng, J. and Chen, L.: Study on Mechanical and Microporous Properties Degradation of Coal with Long-Term Adsorption and Its Effect on Coal and Gas Outburst and CO2 Sequestration, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-5098, https://doi.org/10.5194/egusphere-egu25-5098, 2025.

The spatial distribution, scale, and structural properties of organic and inorganic pore-fracture networks are critical to evaluating shale petrophysical properties. This study conducted a quantitative analysis of the Shahejie Formation shale in the Dongying Sag based on field emission scanning electron microscopy (FE-SEM), revealing the organic-inorganic pore-fracture network characteristics, fractal characteristics and geological controlling factors of low-maturity shale. , and the influence of magnification on the observation results of pore structure was discussed. Results show that shale develops three types of pores: nanometer-sized intragranular pores (such as intercrystalline pores of clay minerals, calcareous mineral dissolution pores, and pyrite intercrystalline pores), and nanometer- to micron-sized intergranular pores (such as brittle minerals). intergranular pores and shrinkage fractures in organic matter) and micron-to-millimeter-scale fractures (such as feldspar fractures and organic-inorganic interface pores/fractures). Among these pores, inorganic pores account for 91.45% of the total pores and contribute 85.1% of the porosity; organic pores account for 8.54% and contribute 14.9% of the porosity; the surface porosity provided by organic pores is 2.2~2.6 times that of inorganic minerals. Among inorganic mineral pores, quartz and clay pores contribute about 49.8% of the storage space, followed by calcite (23.7%). Fractal analysis shows that inorganic pores have higher structural complexity, while organic pores dominated by organic-inorganic interface pores have lower fractal dimensions and relatively weak structural complexity and heterogeneity. The pore size distribution is unimodal, ranging from 10 nm to 4 μm, mainly concentrated in the 200 nm to 1 μm range. As the pore size increases, the contribution of pores of different scales to surface porosity gradually increases, with the micron-scale pore network accounting for 44.8% of the pore volume. The development of nanoscale pores is closely related to the proportion of clay mineral pores, and the degree of crack development is jointly controlled by the main diagenetic minerals (such as clay, quartz, and calcite). Magnification has a significant effect on surface porosity and pore complexity. At magnifications from 5000× to 20000×, the surface porosity of micropores (<200 nm) increased by 29.03 times, and the surface porosity of submicron pores (200-1000 nm) increased by 16.07 times. Fractal analysis further shows that the morphological complexity of inorganic pores is higher than that of organic pores. The number and surface porosity of mineral pores are closely related to mineral content. Pyrite has the largest porosity increment per unit area (2.19), while calcite has the smallest (0.732). These research results provide important data support for sustainable exploration of low-maturity shale and assessment of geological carbon sequestration potential.

How to cite: lin, Z., hu, Q., and Yin, N.: Organic and Inorganic Pore-Fracture Networks in Low-Maturity Lacustrine Shale: Insights from SEM Analysis in the Dongying Depression, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-5399, https://doi.org/10.5194/egusphere-egu25-5399, 2025.

Flooded coal mines have the potential to provide low-carbon renewable heating, independent of surface weather and temperature conditions. To develop an open-loop mine water heating system, it is essential to estimate the amount of heat available within the mine. This estimation is necessary to determine the potential size of the system, assess whether it meets surface demand, and evaluate its economic viability.

Various methods can be used for this estimation. Static methods, which do not account for the influence of time or the underground spatial geometry, rely on simplified variables. These include calculating the background heat flow over the mine's area, estimating the heat stored in the rock volume surrounding the mine, assessing the heat in the mine's water volume, and determining a realistic flowrate to calculate the potential heat extraction.

In contrast, dynamic modelling methods provide a more comprehensive approach by accounting for changes in heat availability over time and the mine's structural architecture.

Using the GEMSToolbox, we performed dynamic modelling on a real two-seam coal mine map and a simplified grid model with comparable size and properties. The results from these dynamic models were compared with static methods, revealing significant differences in heat estimates, varying by orders of magnitude from 10¹⁰ MJ to 10³ MJ of heat produced over 40 years.

Dynamic modelling also offers additional benefits, such as tracking heat variation over time, analysing the impact of different injection and abstraction points, and assessing potential interference from nearby geothermal systems. These findings underscore the advantages of dynamic modelling in developing and optimising mine water heating systems.

How to cite: Sweeney, A., van Hunen, J., Mouli-Castillo, J., and Gluyas, J.: Dynamic vs static assessment of the mine water heat energy potential of coal mines, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-8295, https://doi.org/10.5194/egusphere-egu25-8295, 2025.

The exploration of subsurface geothermal reservoirs has gained significant attention in recent years as a sustainable solution for energy storage and extraction. These reservoirs, ranging from shallow to deep geological conditions, offer immense potential to meet the growing demand for renewable energy while reducing reliance on fossil fuels. By leveraging the Earth's natural heat or over-seasonal waste heat, geothermal systems provide a reliable and environmentally friendly energy source for heating, cooling, and electricity generation. Recent advancements in technology and improved understanding of subsurface geological conditions have expanded the scope of geothermal applications, positioning them as a vital component of the global energy transition.

In this study, various geothermal systems in porous and fractured reservoirs are modeled using flow, heat, and mass transport processes implemented in the open-source software OpenGeoSys (OGS), such as Borehole Heat Exchangers (BHEs). The performance, sustainability, and efficiency of these geothermal systems are analyzed through scenarios involving inter-seasonal multi-cycles of energy use. Additionally, surface energy utilization systems designed for low- and mediate-grade geothermal heat sources, such as geothermal heat pumps and Organic Rankine Cycle (ORC) power plants, are modeled and optimized using the open-source simulation toolkit TESPy (Thermal Engineering Systems in Python).

This work also investigates the mechanisms of interaction between subsurface and surface facilities by coupling geothermal reservoir with thermodynamic process simulation. The integrated simulations enable further optimization of the entire system. This study aims to summarize progress made in modeling geothermal systems for energy extraction and storage using OGS, while also outlining future directions for developing large-scale integrated models that incorporate other renewable energy sources.

How to cite: Chen, C., Witte, F., Kolo, I., and Cai, W.: Modeling closed-loop and open-loop geothermal energy systems for the dual utilization of energy extraction and storage, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-8665, https://doi.org/10.5194/egusphere-egu25-8665, 2025.

In response to growing climate targets and the need for innovative heat management solutions, Durham University, UK, is investigating the reuse of waste heat generated by its high-performance computing (HPC) data centre, which produces up to 1.5 MW of heat. This project explores the potential of repurposing abandoned, flooded mine workings beneath the campus for seasonal thermal energy storage. The system aims to capture surplus heat during the summer and store it within mine water reservoirs for reuse in winter coupled with heat pump technology for building heating, reducing emissions and investigating potential enhancement of campus-wide sustainability.

The Immersion Cooling and Heat Storage (ICHS) projectaddresses critical technical challenges: understanding subsurface water flow dynamics, determining heat injection and retrieval efficiencies, and optimizing borehole configurations between shallower and deeper worked coal seams. Various conceptual designs are evaluated, including dual-depth boreholes for enhanced separation of thermal flow. Initial feasibility assessments highlight opportunities to align this scheme with the university's phased heat network strategy, providing a living laboratory for geothermal research and renewable energy integration.

This presentation will share preliminary findings, insights into borehole site selection, and recommendations for future mine water energy storage schemes. The work contributes to a growing body of research on sustainable heat management in post-industrial landscapes, aligning with broader UK initiatives in Gateshead, Leeds and Edinburgh, as well as Glasgow with the established UKGEOS project.

How to cite: Chapman, S., van Hunen, J., Basden, A., and Gluyas, J.: Data Centre waste heat storage within abandoned flooded mine workings, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-9263, https://doi.org/10.5194/egusphere-egu25-9263, 2025.

Abandoned and flooded coal mines have a huge geothermal potential. By circulating mine water and extracting its heat, it can provide a renewable, low-carbon low-enthalpy heat source for domestic and industrial purposes. But capital costs from drilling into those mine workings are significant, and investigating the geothermal potential of a mine system prior to drilling are essential for the success of any mine water geothermal energy (MWGE) system. Numerical modelling provides a quick and low-cost methodology to assess the feasibility of a planned MWGE system, for example to determine optimal mine water abstraction and re-injection sites.

Past coal mining was typically done using two different mining techniques. 1) The room-and-pillar (also referred to as pillar-and-stall) method was used to mine coal through digging tunnels (galleries and roadways), leaving pillars of coal untouched to prevent collapse of the coal seam. 2) The long-wall mining technique used machines to extract the entire coal seam, and allowed collapse in a controlled manner, thereby creating a porous layer of rubble referred to as ‘goaf’. Often both techniques were used within a single mine system. These two techniques result in very different remnant mine geometries, and it is important to address these differences in any MWGE modelling attempt.

We have developed a computationally fast and flexible modelling tool GEMSToolbox to assess the feasibility of mine workings as MWGE system by combining numerical and (semi-)analytical methods. The tool accounts for both room-and-pillar and long-wall mining techniques. In this study, we investigate the geothermal effects of both techniques for mines that are entirely constructed through one technique only, and for mines that combine the two techniques. Both techniques suffer from significant uncertainties in the effective model parameters: e.g. mine galleries may have collapsed since the mine closure, while for goaf, the effective porosity and hydraulic transmissivity are poorly constrained. Furthermore, in mine systems where both techniques were applied, water preferentially flows through the galleries, which potentially makes heat extraction from the goaf areas less efficient. The results of this study are applied to a real-world mine block in the North East of England.

How to cite: van Hunen, J., Wang, Y., Mouli-Castillo, J., and Tu, J.: The impact of different mining techniques on the geothermal potential of abandoned coal mines, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-9279, https://doi.org/10.5194/egusphere-egu25-9279, 2025.

This study investigates the usefulness of fractal dimension for assessing fracture network geometry especially, in terms of connectivity in petroleum and geothermal reservoirs. We evaluated connectivity using both static and dynamic approaches and analyzed a set of fractal-fracture models and outcrop maps. The models comprise a deterministic fractal-fracture network and a set of thirty random fractal-fracture networks, all sharing the same fractal dimension. The natural dataset includes a series of nested network maps from an outcrop analog. These maps have been studied for their fractal nature, clustering behavior, and flow properties. For the “static” approach, connectivity of the fracture networks is evaluated by considering three different “nodes” in each of the networks, i.e., cross-cutting (X), abutting (Y), and isolated (I). In considering a “dynamic” approach for evaluating connectivity, the flow response is computed along with the integrated “time-of-flight” (TOF) at different time-steps. The networks are converted into simulation-ready fracture continuum models that were run in a streamline flow simulator, TRACE3D. The TOF plots thus generated provide insights into the connectivity between injection and production wells placed at diagonally opposite corners of the flow domain and are used to evaluate flow pathways and the effects of reservoir heterogeneity. They also implicitly indicate the “percolation connectivity” of a fracture network. This may be confirmed by comparing previously reported values of “percolation connectivity” of the outcrop analogs and the TOF plots. The ultimate goal of this research is to determine whether the fractal dimension can serve as a unique identifier for the connectivity of fracture networks. The results derived from both fractal-fracture models and natural maps indicate otherwise. The findings from this study can improve decision-making across various fields, including hydrogeology, resource management, and environmental engineering, leading to more effective strategies for resource extraction and risk reduction.

How to cite: Roy, A., Sahu, A. K., Biswas, R., and Sahoo, B.: Connectivity and Fractal Dimension of Fracture Networks, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-9983, https://doi.org/10.5194/egusphere-egu25-9983, 2025.

Granitic terrains are increasingly utilized for underground disposal of radioactive waste from nuclear power plants, owing to their abundance and superior mechanical properties. However, the heat generated by radioactive waste can elevate burial site temperatures by up to 100°C, potentially compromising structural integrity through thermal expansion and fracture generation. The response of granites to elevated temperature depends on factors such as mineral composition, volatile mineral content, grain size, and pre-existing in situ stress conditions.

This study utilizes experimental techniques namely nanoindentation, micro-CT, SEM imaging, petrography, ultrasonic wave velocity measurements, XRD, and Thermogravimetric analysis to identify and evaluate the temperature dependence of the mechanical properties of two compositionally different granite samples. The initial composition and mechanical properties of the two granite samples were determined using the mentioned techniques. The samples were then subjected to a step-by-step heating protocol ranging from room temperature to 900°C. The properties of the samples were measured at regular intervals along the heating range and were analysed to find out the correlation with temperature.

Results revealed similar but distinct thermal responses between the two samples, with the most pronounced changes occurring between 500-600°C, coinciding with the α-β transition of quartz. Petrographic analysis, micro-CT, and SEM imaging demonstrated significant microcrack development at 600°C. Ultrasonic wave velocities showed progressive reduction with increasing temperature, indicating diminishing mechanical strength. Nanoindentation studies revealed that while the reduced modulus of all minerals decreased with heating, the rate of reduction varied among mineral phases. This comprehensive analysis demonstrates that elevated temperatures substantially reduce granite's strength and structural integrity, with the rate of degradation showing some dependence on compositional variations. These findings have important implications for the selection and engineering of underground radioactive waste disposal sites. Understanding the temperature-dependent behaviour of granite can help prevent potential leakage or environmental contamination, thereby addressing key safety concerns that currently limit broader adoption of nuclear technology.

How to cite: T Ashok, D. and Vishal, V.: Experimental Determination of Mechanical Property Evolution in Granites Subjected to Temperature Fluctuations: Implications for Safe Subsurface Disposal of Radioactive Waste, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13059, https://doi.org/10.5194/egusphere-egu25-13059, 2025.

Geothermal energy refers to the energy derived from the Earth’s heat and is a promising renewable resource, that can be harnessed for electricity generation, direct heating, and other industrial applications. Although geothermal energy has been utilized for various applications in several parts of the world for decades, its potential remains largely untapped in India. India’s geothermal energy development is still in the nascent stage compared to other renewable resources like solar and wind. However, given the country's growing energy demand and commitment to sustainable energy solutions, geothermal energy could play an important role in the coming future.

Over the last few decades, the identification of surface manifestation, followed by geological, geochemical, and geophysical investigations by the Geological Survey of India, the National Geophysical Research Institute, and many other organisations, demarcated ten geothermal provinces in India. Studies indicate that geothermal potential in India is mostly concentrated in the hot spring regions, which are connected to the deep geothermal reservoir by fault and fracture systems. These need to be explored further for exploitation based on their reservoir potential and sustainability.

In recent years, the Government of India has taken initiatives to carry out detailed geothermal exploration, which will be followed by exploitation in most potential zones. Based on the knowledge, three regions have been identified, and work is in progress by various research organisations and government/private institutions for exploration and exploitation. These are (i) Puga-Chumathang-Panamik in the Ladakh Himalayas, (ii) Tattapani in Central India, and (iii) Manuguru in the Godavari Gondwana basin. Hydrogeochemical and multiparametric geophysical investigations are underway in the above regions. Recent thermal, geological, and hydrogeochemical results, along with the previous knowledge from the Ladakh Himalaya and Central India indicate spatial distribution of the geothermal reservoir with medium to high enthalpy geothermal potentials. This will be followed by drilling exploratory wells, to constrain various geothermal parameters. These efforts mark a critical step towards harnessing India’s geothermal resources for sustainable energy production.

How to cite: Ray, L., Chopra, N., Dutta, A., Kurakalva, R. M., Sidagam, E. R., Podugu, N., Prajapati, S. K., Dudhate, A. P., and Satyanarayanan, M.: Geothermal Energy in India: Current Status and Future Prospects, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-15315, https://doi.org/10.5194/egusphere-egu25-15315, 2025.

Mining activities occur on all inhabited continents, which is why many countries are faced with the question of how exhausted mines can be utilised sustainably. One promising option is their use as energy sources, with flooded structures acting as sub-surface heat exchangers. The large water volumes offer significant potential for heating and cooling. However, the exploitation of abandoned mine is associated with high costs due to preliminary investigations and drilling. In order to minimise the economic risk, a reliable forecast of the mine water temperature is essential to ensure long-term economic viability. As complex thermal-hydraulic simulations require specific expertise, they are difficult to access for many energy suppliers and mine operators. This underlines the need for user-friendly models that allow an initial assessment of the potential without in-depth knowledge of modelling.

Only a few reduced models for predicting mine water temperature exist in the literature. While analytical models impress with extremely short calculation times (Milliseconds for decades), they are not able to take seasonal storage effects into account. Reduced numerical models from the literature can consider these transient effects, but require significantly longer calculation times (Minutes for decades), especially for turbulent flow regimes. This is too time-consuming for a comprehensive parameter study. In order to combine the advantages of both approaches, a new model is required that takes seasonal storage effects into account and works in an acceptable computing time (< 1 minute for decades).

The newly developed model combines two coupled sub-models: The heat transfer in the rock is solved numerically using an implicit finite volume scheme, whereby an irregular grid enables an efficient calculation. The energy transport in the fluid is modelled using an analytical solution. The verification using a reference case shows a high accuracy of the model. At a constant reinjection temperature, the deviation of the outlet temperature after twenty years is 3 % compared to the benchmark (fully numerical axisymmetric CFD simulation). With cyclical heat loads, the maximum deviation occurs for the inlet temperature with 3,5 %. At the same time, the model is around 750 times faster than the benchmark calculations with a run time of 1 s for two decades.

In order to test the model with practical operating modes, it is compared with an existing CFD simulation of the north-west field of the mine in Ehrenfriedersdorf, Germany. The comparison focuses on the temperature development of the mine water at the outlet, assessing how well the model captures seasonal variations and contributes to optimizing operational decisions.

How to cite: Krause, W., Ebel, T., Oppelt, L., Wunderlich, T., Raithel, F., Grab, T., and Fieback, T.: A reduced numerical model for predicting temperature dynamics in flooded mine galleries under seasonal heat loads and storage conditions, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-15555, https://doi.org/10.5194/egusphere-egu25-15555, 2025.

As the world transitions to greener sources of energy, understanding how to best plan this transition becomes a critical challenge. A relatively recent approach contributing to the decarbonisation of heating and cooling infrastructure is repurposing abandoned mine networks to deploy geothermal energy technologies. These technologies utilise the subsurface to sustainably provide heating and cooling to buildings and are one of the key renewable technologies contributing to and shaping the decarbonisation of our energy landscape. Different configurations for exchanging heat with the ground can be used, such as closed- or open-loop systems, as well as operational strategies, such as utilising thermal storage, which can affect the subsurface requirements and design of the system.

With mining operations being increasingly shut down, geothermal mine systems not only constitute a sustainable method to providing heating and cooling energy, but also repurpose these abandoned sites and subsurface networks. Additionally, while geothermal energy technologies are generally highly efficient, important barriers to their wider implementation include relatively high capital costs due to subsurface-related uncertainties and the need for earthworks, as well as the dependency on groundwater flow conditions for certain applications. Integration with mines can contribute to overcoming these barriers, such as by minimising required earthworks, by reducing uncertainty through access to high quality data on the state of the subsurface, and by offering advantageous subsurface conditions for a geothermal system that takes advantage of the flow of water through the tunnels.

Integrating geothermal technologies within abandoned mine infrastructure to provide heating and cooling to buildings has been demonstrated and proven in several European countries in recent years. Large-scale projects, such as the Gateshead heat network in the UK (6MW heat pump) and the district heating system in Heerlen, Netherlands, showcase the potential of using flooded subsurface tunnel networks to provide geothermal energy at a large-scale. However, one potential smaller-scale application that has received little attention, and is the focus of this work, is utilising mining shafts.

Abandoned mining shafts are typically covered and flooded, making them a potential low hanging fruit for incorporating geothermal energy applications. While this concept is discussed in literature, more information is needed on the applicability and suitability of different geothermal configurations under different mine shaft conditions. This work contributes towards bridging this gap by utilising advanced finite element modelling methods to simulate a typical mine shaft, adopting a case study from the UK, and investigating in detail the potential energy yields of different geothermal applications under different conditions. Importantly, the effect of natural convection, expected to be significant in a flooded shaft compared to saturated soil, is carefully considered, acknowledging the complexities this introduces due to the difficulty of computational flow modelling at this scale.

How to cite: Makasis, N.: Exploring the use of mining shafts with geothermal systems using numerical modelling, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17268, https://doi.org/10.5194/egusphere-egu25-17268, 2025.

The Jharia Coalfield (JCF), the magnificent pocket of coking coal in the southern part of the Dhanbad district of Jharkhand India, has always remained at the peak of attention for the technological challenges that occurred during the mining of coal. The JCF is also the most critically highlighted coalfield as it is the only known depository of prime coking coal in India which is infamous for its extensive coal fires ignited mainly due to its dynamic spontaneous combustion nature. Earlier studies reported significant anomalous temperature variations in the range of 160-200⁰C along subsurface cracks and vents; also the geothermal gradient is locally high in  the basin to be around 40-45⁰C/km. The implementation of geothermal heat extraction technologies to utilise the wasted heat underneath would require a comprehensive understanding and estimation of the techno-economics of various operational and maintenance costs. The economic assessment for a 5 MW geothermal plant revealed an initial investment cost of 12.02 (MM$) and 8.05 (MM$) and NPV to vary between 27.08 (MM$) to 31.04 (MM$)  respectively for the source temperature of 100⁰C and 150⁰C in the burning JCF basin.

How to cite: Dutta, A. J., Mishra, C., Chaturvedi, R., Konwar, D., and Kulkarni, S. D.: Techno-Economic Assessment of Geothermal Energy Resource in the Jharia Coal Field of India, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17341, https://doi.org/10.5194/egusphere-egu25-17341, 2025.

As the global energy transition accelerates, innovative solutions such as Mine Water Heat Systems (MWHS) are emerging to address the dual challenges of energy storage and decarbonised heating and cooling. This study focuses on the development of a business model for a heat geobattery system, which utilises abandoned mine workings to store thermal energy for heating, cooling, and thermal storage services, leveraging waste heat from a data centre.

We identify the operational roles, services, and responsibilities of a Mine Water (MW) operator and assess their impact on the heat supply chain. The UK’s regulatory landscape for MWHS is also investigated, highlighting gaps, barriers, and opportunities for regulatory enablement.

Additionally, we aim to build a database of technical risks to quantify the costs of mitigation strategies. This involves identifying critical risks associated with MWHS, including technical failures, environmental impacts, and regulatory non-compliance. Potential liabilities, such as pump and heat exchanger failures, mine gas release, and groundwater disruption, are analysed alongside their consequences, including downtime, environmental harm, and financial penalties. Mitigation strategies, such as regular maintenance, water quality monitoring, emergency response plans, and compliance frameworks, are proposed, with their costs estimated. These measures ensure system reliability, environmental protection, and adherence to regulatory requirements, enabling safe and efficient MWHS operations.

This study underpins the development of an investor-ready business model for the commercialisation of a heat geobattery system. Emphasis is placed on aligning financial incentives with operational feasibility, customer demand, and supply structure. By integrating these findings with the rest of the Galleries2Calories project, this research provides a framework for the seamless adoption of heat geobatteries. The outcomes contribute to understanding how MW operators can enhance the heat supply chain while addressing critical regulatory and environmental considerations.

How to cite: Mouli-Castillo, J., Watson, S., Nandagavi, P., Breunig, H., Swan, L., Smith, S., and Townsend, D.: Towards Investor-Ready Business Models for Mine Water Heat Systems: Regulatory, Technical, and Operational Insights for the Heat Geobattery, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17354, https://doi.org/10.5194/egusphere-egu25-17354, 2025.

Underground mines, once vital industrial hubs, hold immense potential for innovative applications, including Mine Thermal Energy Storage (MTES). MTES repurposes partially and fully flooded mine cavities as reservoirs for storing surplus heat or cold, presenting a novel alternative to conventional Aquifer Thermal Energy Storage (ATES). While promising, MTES faces challenges such as scaling, corrosion, energy loss, and interactions between the geological matrix and technical infrastructure.

To address these challenges, TU Bergakademie Freiberg has established a living MTES geo-lab at the historic Reiche Zeche silver mine. Key features of this facility include a 21-cubic-meter water reservoir and over 90 temperature sensors embedded in Freiberg Gneiss. The pilot-scale MTES simulator setup allows for continuously monitoring heat transfer during thermal energy injection and extraction cycles realized by a mobile heat pump system. Early findings are revealing an average background rock temperature of 12 °C, a fast conductive heat transport within the rock as well as a good storage potential with elevated rock temperatures of up to 25 °C in approximately 2 meters from the water body. However, significant heat losses across system boundaries have been observed, with advective heat transport via flowing water identified as the primary contributor.

Parallel laboratory-scale experiments using column flow setups and batch reactors simulate MTES conditions, exposing rock and mine water to temperature cycles ranging from 10°C to 60°C. These experiments demonstrate significant chemical changes, including the precipitation of 90% of dissolved iron. These findings offer valuable insights into the chemical stability and thermal efficiency of MTES systems.

Two complementary methods were employed to quantify effective inflow and energy dissipation caused by mine water movement. First, a dilution test with NaCl was conducted. Second, inflowing water volume was calculated based on reservoir water level reductions. Results indicate that the calculation based on inflowing water volume provided more reliable values, while the formula used in the dilution test requires further refinement.

Additionally, numerical simulations using OpenGeoSys (OGS) software are being developed to assess the influence of fracture networks in the surrounding rock formation on heat storage and recovery performance. Preliminary results indicate that fractures enhance advective heat transport, leading to lower heat recovery ratios during cyclic operation.

How to cite: Arab, A., Binder, M., Oppelt, L., Chen, C., Wiedener, R., Schenker, F., Engelmann, C., Späker, C., Lotter, T., and Scheytt, T.: Storing Thermal Energy in Underground Mines: In Situ Simulations at the Freiberg Living Geo-Lab, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-19064, https://doi.org/10.5194/egusphere-egu25-19064, 2025.

The growing stringency of the European Union’s environmental policies, particularly in the area of atmospheric protection, has intensified efforts to mitigate greenhouse gas emissions across multiple sectors. Among the most concerning pollutants is methane (CH₄), well known for its high global warming potential. Recent regulations, including a methane ordinance, reinforce the necessity of reducing emissions from various sources, notably underground coal mines, where ventilation air methane (VAM) accounts for a significant fraction of overall greenhouse gas outputs.

Poland’s mining landscape presents unique challenges in harmonizing environmental objectives with economic imperatives. Of particular note is the strategic importance of coking coal, which the EU deems essential for steel production. In response, initiatives have emerged to uphold the necessity of steel-making while concurrently striving to meet stringent emissions reduction benchmarks. Within this context, the Central Mining Institute - National Research Institute in Poland (GIG) is spearheading research and development of cutting-edge solutions aimed at mitigating methane emissions from ventilation air streams. Central to these endeavors are thermal and catalytic oxidation methods, which offer a dual advantage: lowering methane levels and generating energy from the oxidation process. By converting VAM - even at relatively low CH₄ concentrations - into useful heat, these advanced technologies can significantly reduce overall greenhouse gas emissions. Concurrently, they provide opportunities for energy recovery, thus partially offsetting the operational costs associated with emission control. This model fosters greater economic viability while ensuring a more environmentally responsible approach to coal mining, critical for sustaining steel production across the EU.

How to cite: Hildebrandt, R. and Kruczek, M.: Emerging Technologies for Methane Emission Control and Energy Recovery in Underground Coal Mining, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-19602, https://doi.org/10.5194/egusphere-egu25-19602, 2025.

Developing geothermal energy utilization technology is critical for achieving a low-carbon, high-efficiency energy system, and carbon neutrality objectives. The deep borehole heat exchanger (DBHE) represents a viable solution for extracting geothermal energy to meet building heating needs, especially in coal mines or oil fields with abundant depleted deep boreholes. In this study, a more comprehensive three-dimensional numerical model was constructed, incorporating segmented design parameters of the DBHE's inner pipe. The model's validity was confirmed through comparison with field experiment monitoring data. Subsequently, a series of long-term simulations were conducted to assess heat extraction performance, elucidating the influence mechanisms and interactive effects of various inner pipe parameters.

Additionally, a thermal-economic analysis was performed from a system-level perspective to quantify and evaluate the impact of inner pipe parameters on the DBHE's heat extraction performance, including assessing the necessity of inner pipe insulation. Results indicate that, under the specified conditions, reducing the thermal conductivity of the inner pipe increases the outlet water temperature while extending the payback period. Furthermore, greater drilling depth and lower circulation flow rate enhance the effectiveness of inner pipe insulation in improving the DBHE's heat extraction capacity, whereas the diameter of the inner pipe exerts a limited effect. These findings provide valuable guidance for the system design of practical DBHE heating projects in areas with depleted deep boreholes, enabling informed selection of inner pipe parameters.

How to cite: Cai, W., Xia, Q., Wang, F., Chen, C., and Meng, B.: Techno-economic performance analysis of deep borehole heat exchanger heating system towards transforming depleted deep boreholes, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20061, https://doi.org/10.5194/egusphere-egu25-20061, 2025.

Humans craft insights through "social processes pertaining to the production, preservation, accumulation, circulation, and appropriation of knowledge" (¹ p.429). Insights and related practices shape the socio-ecological niche humans live in. Partaking makes social processes (practices) effective. Promoting geoethics for inspiring politics is founded upon the following:

Earth: Contemporary societies connect Earth into a single complex-adaptive social-ecological system² through global supply chains, an all-embracing division of labour, a planetary technosphere, and a worldwide knowledge system³. Cycles of matter, energy, and information tie socio-economic systems and the planet's physical and biological systems. The hegemonic contemporary culture tackles Nature as a cheap, nearly unlimited resource, nourishing the primary narrative of planetary-scale anthropogenic change.

World: The human condition, agency and practices encompass reproduction, work, and governance, regardless of the role a specific individual, collective, or institution human agent has at a given time and place. Using Hannah Arendt's analysis of the human condition⁴, laborans tell of the struggle for biological and social reproduction (at subsistence or affluence levels). Homo-fabers' story is about building and operating the technosphere. Zoo politikons embody civism, a citizen's political and cultural virtues and sentiments.

Rupture: Over the past few centuries, homo-faber has built a planetary technosphere conceived by zoon-politikons of primarily European origin^5,6. The onset of disruptive planetary-scale anthropogenic change⁷, i.e. the Anthropocene, terminates peoples' unintentional impact on Earth. Instead⁸, it challenges the zoon-politikons and homo-fabers to secure lasting reproduction for all.

Practice: Geo-societal narratives acknowledge inequality, i.e. people (human agents) acting as laborans, homo-fabers or zoon-politikons, and power relations, i.e. zoon-politikon's political and cultural perspectives guide homo faber's engineering of the technosphere, which determines laborans' experience of Earth System dynamics. Comparative justice requires partaking in crafting narratives.

The Earth scientists' conventional narratives encompass socio-economic development (e.g. production of goods, living conditions), individual well-being and cultural values, e.g. favouring the sustainable functioning of the telluric Earth System, and cultural or metaphysical perspectives like the evolution of life-bearing planets. However, informing the handling of disruptive planetary-scale anthropogenic change, i.e. going political, Earth scientists' narratives are about the geo-societal, i.e. they must recognize people's labour to reproduce biologically and socially, people's work to build and run the technosphere, and people's acts as citizens.

• 1) Renn, J. The Evolution of Knowledge - Rethinking Science for the Anthropocene. (Princeton University Press, 2020).
• 2) Otto, I. M. et al. Human agency in the Anthropocene. Ecol. Econ. 167, 106463 (2020).
• 3) Rosol, C., Nelson, S. & Renn, J. Introduction: In the machine room of the Anthropocene. Anthr. Rev. 4, 2–8 (2017).
• 4) Arendt, H. The Human Condition. (The University of Chicago Press, 1958).
• 5) Mokyr, J. A Culture of Growth. (Princeton University Press, 2016). doi:10.1515/9781400882915
• 6) Reinhard, W. Die Unterwerfung der Welt - Globalgeschichte der Europäischen Expansion 1415-2015. (Verlag C.H. Beck oHG, 2016).
• 7) Summerhayes, C. P. et al. The future extent of the Anthropocene epoch: A synthesis. Glob. Planet. Change 242, 104568 (2024).
• 8) Hamilton, C. Defiant Earth - The Fate of Humans in the Anthropocene. (Wiley, Polity Press, 2017).

How to cite: Bohle, M.: Geo-societal Agency and Narratives: Framing the Human Condition, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-65, https://doi.org/10.5194/egusphere-egu25-65, 2025.

The divide between the Global North and South in the geosciences has been recognized as one of the most pressing challenges of our time. It is widely accepted that this gap must be addressed through visionary leadership and strategic initiatives that draw upon the unparalleled expertise and resources concentrated within Global North institutions. A comprehensive framework is proposed here to foster equity and collaboration, ensuring the participation of scholars from all regions while maintaining the highest standards of academic rigor.

Three critical pillars for bridging this divide have been identified. First, the deployment of expert teams from the North to train local researchers in the Global South should be prioritized during global fieldwork, as this model has consistently proven effective for capacity building. Second, the importance of performative Diversity, Equity, and Inclusion (DEI) measures must be emphasized, including symbolic appointments and one-time funding schemes designed to raise awareness of systemic inequities. Finally, conferences and workshops should continue to be held in the Global North, ensuring logistical convenience and robust participation. For those unable to secure visas or travel funds, virtual attendance options can be considered as a viable alternative.

This framework also seeks to address the growing demand for environmental justice in research. By focusing discussions on resilience and adaptation rather than directly referencing complex socio-political histories (avoid using the G-word), a narrative of hope and progress can be fostered. Importantly, the recommendations presented here assume that the Global South operates as a cohesive monolith, enabling streamlined approaches that are universally applicable and unburdened by the complexities of local disparities or intra-regional inequities.

This is satire.

How to cite: Gani, S.: How (not) to Bridge the Global North-South Divide in the Geosciences: A Framework for Impactful Collaboration, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-621, https://doi.org/10.5194/egusphere-egu25-621, 2025.

Skeptical Science is a volunteer-run website publishing refutations of climate misinformation. Some members of the Skeptical Science team actively research best-practices refutation techniques while other team members use these findings to share debunking techniques effectively either in writing or through presentations. Skeptical Science is published in English but translation capabilities were added in 2009. Many volunteer translators have taken advantage of this functionality to create content in their native language.  With this submission we highlight what is already available and what the challenges are for such a volunteer-based effort.

Many of the rebuttals to climate myths have been translated into 1 to 28 languages thus far but there's a large variety in how many translations exist for one rebuttal. In addition, many rebuttals have seen updates in their English version which haven't yet found their way into already existing translations.

In addition to providing translations for selected content published as rebuttals or blog posts on Skeptical Science, we also coordinate translations for publications like The Debunking Handbook, The Conspiracy Theory Handbook and the Cranky Uncle game which are then made readily available on our website.

How to cite: Winkler, B.: Making climate science more easily accessible by providing translations on Skeptical Science, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-1440, https://doi.org/10.5194/egusphere-egu25-1440, 2025.

Human activities are the major cause for what has been recognized as the 6^th Mass Species Extinction. It is thus important to spread knowledge and raise awareness about the issues because we depend on biodiversity in ways that are not always apparent or appreciated. In December 2022, delegates from 196 governments adopted the Kunming-Montreal Global Biodiversity Framework (GBF) under the UN Convention on Biological Diversity (CBD). The GBF supports the achievement of the Sustainable Development Goals and sets out an ambitious pathway towards living in harmony with nature by 2050. Meanwhile, the lengthy ratification process is no guarantee of full enforcement after entry into force. Typically, different interest groups may resist top-down measures affecting them. This is known as the implementation gap of international treaties and agreements. Here we describe a role play intent on matching a key element of the top-down GBF, namely the establishment of interconnected marine protected areas (MPAs), with bottom-up awareness raising and deliberation among diverse stakeholders. Eleven characters of stakeholders have been developed through wide-ranging interviews and literature research. For each stakeholder an information sheet explains the context and his or her role. Based on the interviews, a general introduction and guidance for a moderator is provided together with a tentative schedule. Emphasis is placed on allocating sufficient time for the debriefing after a round of deliberations aiming at consensus towards establishing an effective MPA. The assumption is that the debriefing produces most learning about why biodiversity protection is essential and how to sustain a respectful dialogue process with persons holding different positions from one’s own. A first round of tests with young adults has already generated useful feedback allowing some improvements of the initial set. We propose the role play for wider use as a low-entry support for bottom-up participation in GBF implementation.

How to cite: Nauen, C. E. and Morales Yokobori, M. L.: Protecting Blue Horizons – A role play to make an MPA work, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-1809, https://doi.org/10.5194/egusphere-egu25-1809, 2025.

Valtellina is an Alpine region in northern Lombardy (Italy) that largely coincides with the basin of the Adda River upstream of Lake Como. The Alps represent a complex, fascinating, and at the same time, vulnerable environment that holds immense importance for scientific research while offering endless opportunities for educational activities based on direct observation. These activities are adaptable to students of all ages. Exploring the geological and geomorphological aspects of the Alpine environment is particularly crucial for understanding their influence on the structure and evolution of the territory, raising awareness of natural hazards, and deepening knowledge of Geological Sciences. The significance of this knowledge has been repeatedly emphasized, especially today, as these disciplines play a fundamental role in addressing current climatic and environmental challenges and promoting sustainability goals. Morbegno, the main center of the Lower Valtellina valley, is home to the Istituto Comprensivo 2 Damiani. In 2020, the lower secondary school of this institute earned the European certification of Alpine School, introducing a curriculum focused on Alpine environmental and socio-economic processes. The program aims to reconnect students with the mountainous territory, fostering awareness of its characteristics, resources, and opportunities. This interdisciplinary educational model integrates the mountain into the learning pathway, involves local stakeholders, and combines the use of technology with hands-on field experiences. Geology, geomorphology, and outdoor education play a pivotal role in the curriculum, further aiming to cultivate a positive engagement with Geological Sciences among young students. The school also seeks to integrate geoethics into the curriculum through educational games, debates, and an inquiry-based approach developed in line with the outcomes of the Geoethics Outcomes and Awareness Learning (GOAL) project, co-funded by the Erasmus+ Programme of the EU. The proposed contribution aims to showcase the school’s organization and activities, providing inspiration and practical ideas for implementing similar initiatives.

How to cite: Cameron, E. and Di Capua, G.: Bridging Mountains and Minds: An Educational Experience in the Alpine Region, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2334, https://doi.org/10.5194/egusphere-egu25-2334, 2025.

The switch in definition of the Anthropocene concept first proposed in 2000 in just one year, 2024, from a 1952 varved lake sediment to humanity’s cumulative impacts on the Earth System starting in the Late Pleistocene was an extraordinary development in the geoscience profession. Launched as a traditional Time Scale inquiry, the 2009-2024 journey of the designated Anthropocene Working Group (AWG) became unconventional because of its focus on mid-20^th century atomic bomb tests broadly coeval with two dozen accelerating Earth System and socioeconomic trends as well as its premature communications with news media. On 4 March 2024, the AWG proposal for an Anthropocene epoch/series was rejected by the umbrella authorities of the International Commission on Stratigraphy and International Union of Geological Sciences. Their decision was wrongly interpreted by some, including leaders of the former AWG, as a denial of scientific evidence for anthropogenic climate change. This unleashed conflicting news coverage and thus a need for clarifying discourse within geoscience, across related disciplines, as well as across society with its growing anxiety about the Earth’s deteriorating health. The helpful outcome is that the Anthropocene Event uniquely equips Earth Governance, a surging focus of global influencers and authorities, with a holistic Earth-Human Ecosystem framework.

How to cite: Koster, E.: The Anthropocene Event as a holistic framework for Earth Governance, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2621, https://doi.org/10.5194/egusphere-egu25-2621, 2025.

This presentation explores the concept of 'agency' in the context of climate change through in-depth interviews with scientists. Drawing on Emirbayer and Mische’s (1998) definition of agency as a relational construct influenced by habit, imagination, and judgment, I investigate how scientists articulate their self-perception of agency and the emotions tied to it—such as solidarity, fear, and empowerment.

Leveraging anthropological scholarship on emotions (Hochschild, 1983; Scheer, 2012) and affect theory (Ahmed, 2004; Berlant, 2010), I examine how networks and practices shape these emotional experiences (Mesquita, 2022; Salmela & von Scheve, 2017, 2018). I aim to connect scientists’ reflections on their emotional engagement with emerging ideas of radical care.

The presentation will address the panel question: How can scientific institutions prevent reinforcing the status quo and instead contribute to radical transformations? By analyzing the sociological production of emotions within the scientific community, I hope to uncover new insights into how both movements and scientists can co-produce emotional narratives for greater collective action against climate change.

How to cite: Tyagi, A.: Scientists as agents of 'radical care': 'emotional practices' as changing the way scientists imagine themselves, their peers and, their science, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2876, https://doi.org/10.5194/egusphere-egu25-2876, 2025.

In an increasingly interconnected and vulnerable world, combining pragmatism and relationality in geosciences is essential for addressing environmental challenges ethically and responsibly. Relational Geoscientific Pragmatism (RGP) underpins the method proposed by geoethics, offering tools to manage geological complexities within the context of modern societies. It fosters an integrated perspective where geosciences are closely linked to social responsibility and sustainability.

The geoethics method places respect for the environment, the sustainable management of natural resources, the safety and well-being of current and future generations at its core. It consists of integrating a practical, solution-oriented approach in geosciences with an ethical value system that guides decisions related to the management and human interaction with the Earth system. It focuses on context-specific solutions, applying rigorous scientific methods to the relationships between natural phenomena, societal needs, and decision-making processes in each context.

The fundamental elements of the geoethics method can be outlined as follows:

• Geoscience knowledge: it is fundamental to understanding natural phenomena and environmental dynamics, addressing challenges related to natural resource management, climate change, and environmental sustainability, and guiding the decision-making process. This knowledge enables accurate risk assessment and resource evaluation, offering objective and reliable data that underpin informed, evidence-based decisions.
• Interdisciplinarity: environmental issues are inherently complex and demand the integration of knowledge from a wide range of disciplines, including geosciences, social sciences, economics, law, and philosophy. The aim is to cultivate a holistic understanding of both natural systems and social contexts, ensuring that the interventions address the full complexity of the challenges, respecting their multifaceted nature.
• Responsibility and scientific analysis: geoethics demands all stakeholders to act responsibly, being aware of the consequences of their actions and balancing conflicting interests. The rigorous application of scientific analysis ensures that every decision is based on objective, verifiable, and up-to-date data. By prioritizing science, the geoethics method can navigate the value conflicts and ethical priorities that inevitably arise in decision-making processes.
• Defining ethical dilemmas and scenarios: The Geoethics Method identifies and analyse ethical dilemmas in human-environment relations, such as balancing economic growth with nature conservation, ensuring intergenerational justice, and protecting vulnerable communities. It facilitates scenario creation by envisioning outcomes of actions and evaluating them against sustainability, equity, and environmental respect.
• Inclusivity and dialogue: the Geoethics Method promotes the active involvement of all relevant stakeholders, including scientists, decision-makers, and local communities. This relational approach aims to find a reasonable alignment of values on which to base the choice of the best course of action for a given spatial and temporal context. Every proposed solution must be assessed not only for its technical feasibility but also for its capacity to address the needs and expectations of all stakeholders, thereby creating a dynamic balance between ecological and social concerns.

The Geoethics Method paves the way for responsible actions, helping decision-makers navigate modern challenges and create a geological governance model that seeks to strike a balance between scientific rigor and ethical and social needs.

How to cite: Peppoloni, S. and Di Capua, G.: Relational Geoscientific Pragmatism as the foundation of the Geoethics Method, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2906, https://doi.org/10.5194/egusphere-egu25-2906, 2025.

The American Geosciences Institute, through its GRANDE project, has been evaluating how geoscience programs and professionals have leveraged the impacts of natural disasters to expand research and educational opportunities. We used natural disasters as a proxy for climate change impacts to better understand the community’s strategic response to events and risk tolerance to natural hazards. Given the fact that the discipline understands the causes, impacts, and risks of such natural events, we hypothesized that the geoscience community is particularly well-positioned to lead the way in adaptation and mitigation efforts related to climate and hazard impacts in their professional activities.

Within the United States, our findings indicated that between 2000 and 2020 there was no systemic engagement with climate and hazard impacts in terms of research production, research funding, or educational efforts. Additionally, we conducted several surveys regarding individual responses to natural disasters and climate impacts, including a cost-choice analysis of career decisions. The results showed little material response by geoscientists to specific climate impacts and scant consideration of hazard risk when considering job opportunities.

One noteworthy finding in the cost-choice analysis revealed that US geoscientists were more open to jobs in locations with higher risk when salaries increased above $50,000, and especially so when salaries exceeded $100,000 per year.  Except for Millennials, geoscientists across all other generational cohorts consistently opted for jobs with higher salaries regardless of other factors. Those choosing jobs with salaries less than $50,000 per year chose jobs in rural locations with relatively low hazard risk, whereas those choosing higher salary jobs, chose jobs primarily in urban settings, with higher hazard and crime risk. Higher income thresholds appeared to increase risk tolerance overall, with community amenities and resources significantly outweighing environmental risks.

From this analysis, it appears that the US geoscience community is not positioned as a proactive change agent relative to climate impacts on society, and there appears to be no long-term strategic investments in building the research and educational capacity, as well as the labor pool, to meet the expected demand for skilled professionals to address climate change and hazard impacts over the coming decade. Given the increasing frequency and severity of impacts from natural hazards, the cost of a lack of dedicated long-term investment in addressing these issues is staggering. Should the US geoscience community galvanize its focus around addressing climate impacts, the results of this study indicate that financial investments, especially in terms of occupational salaries, must meet a minimum threshold to attract geoscientists into these critical occupations. The drivers of this financial threshold are unknown, but we hypothesize that this is the socially accepted level for fundamental stability for individuals living in the United States, covering expenses such as insurance, healthcare, and housing.

We are interested in engaging in dialogue with colleagues outside of the United States to test whether different social systems provide the needed stability to enable scientists to be more effective agents of change.

How to cite: Keane, C. and Gonzales, L.: The Unfulfilled Potential of U.S. Geoscience: Strategic Gaps in Climate Adaptation and Hazard Mitigation Efforts, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3324, https://doi.org/10.5194/egusphere-egu25-3324, 2025.

The Sendai Framework for Disaster Risk Reduction (2015 – 2030) calls for incorporating science into the policy process. However, this carries the risk of politicizing science, and therefore, may blur the boundaries of the roles of the different risk management actors. These difficulties are aggravated in the context of an emergency or natural disaster, where scientists advise the authorities. In these situations, decision-makers need to respond with the utmost precision to three basic questions: i) what phenomena will occur, ii) when will they occur, and iii) where will they impact? Despite the efforts of the scientific community to conduct increasingly accurate studies on natural events, uncertainty is often high and/or unavoidable. This uncertainty, in an environment of pressure, urgency, and ineffective communication, can lead to the proliferation of non-consensual, incomprehensible, misunderstood, and erroneous information. In an extreme case, it can even aggravate the impact of such a natural disaster (e.g., l’Aquila earthquake in 2009). On the other hand, in a context of climate change—where the magnitude and frequency of many events are increasing—and unstoppable demographic expansion, the trend is towards greater risk. Moreover, the appearance of increasingly complex and strong relationships between different types of events, with the occurrence of concatenations and cascading effects, increases uncertainty, and therefore makes it difficult to design strategies for prevention, action, and recovery. Multi-hazard analyses can help to reduce this uncertainty in the complex scenarios that are plaguing society today and will continue to do in the future. Multi-hazard analyses are a first step towards a transdisciplinary, cross-sectoral, and cross-border multi-risk management plan that is based on scientific knowledge. The greater precision of risk estimation will contribute to better supporting decision-makers, thus implying the ethical communication of information that reduces misunderstanding, thereby contributing to the resilience of societies.

This research was partially funded by the European Commission (EC) EVE grant (DG ECHO Horizon 2020, Ref. 826292) and the CSIC grant MAPCAN (CSIC Ref. 202130E083).

How to cite: López Saavedra, M. and Martí, J.: Multi-hazard analyses and their implications for the defense of society against natural phenomena, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4220, https://doi.org/10.5194/egusphere-egu25-4220, 2025.

Climate change requires urgent action. Increasingly, the world is considering technology-based climate intervention approaches—often called geoengineering. Many of these approaches are untested and the consequences are not yet well understood. While climate intervention research has been justified as being necessary in order to expand the range of options available to policy makers in the future, and is thus receiving increased research funding and attention, many questions remain on efficacy, risks and potential harm versus potential benefits.

Recognizing the need for guiding principles in this dynamic and sometimes controversial space, in 2022, AGU launched its plan to develop an Ethical Framework for Climate Intervention Research—a code of conduct to guide climate intervention research measures that may be needed in addition to emissions reduction.   The resulting proposed ethical framework principles, facilitated through global community participation, are now publicly available for download in nine languages.  The foundations for these updated principles and associated recommendations, the process by which they were developed, their implications, and the current process for global dissemination and engagement will be discussed. 

How to cite: Williams, B., Shimamoto, M., Lachance, J., and Shultz, L.: Navigating Climate Intervention Research Issues and Opportunities: A Thoughtful and Inclusive Path Forward, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4540, https://doi.org/10.5194/egusphere-egu25-4540, 2025.

As climate change continues to pose challenges, it is important to promote the fields of climate and ocean education and communication.  This poster presents my two Masters research internships.  

For my Master 1 internship, I investigated how climate change is perceived spatially in the city of Nice, taking into account the experiences of both local residents and tourists.  This has highlighted the importance of understanding diverse perspectives in climate communication.

For my Master 2 internship, I examine the ways in which climate change adaptation is mobilised in simulation/games.  My aim is to identify the most suitable games for different purposes, such as facilitating community discussions, supporting decision-making for communities and municipalities and enhancing education in schools. 

I will also present some of the common learning elements of the two internships, as well as difficulties encountered.  Please visit my poster and share your thoughts on educational strategies for addressing climate and ocean challenges.

My Master 2 internship is made possible by the kind support of the following:

• Futurs-ACT, a regional research network in Nouvelle-Aquitaine;
• Benoît Sautour, Université de Bordeaux - OASU UAR POREA; 
• Nicolas Becu, La Rochelle Université, CNRS - LIENSs.

How to cite: Promduangsri, P.: Climate change in two research internships : Spatial perspectives and games, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4989, https://doi.org/10.5194/egusphere-egu25-4989, 2025.

The Anthropocene demands a critical reassessment of humanity’s relationship with the Earth, bringing geoethics, geoenvironmental education, and the concept of sense of place to the forefront of sustainable human-Earth interactions. Geoethics addresses the ethical dimensions of these interactions, underscoring the responsibility of geoscientists to advance sustainable practices and raise public awareness of pressing environmental issues. Through a systematic literature review of 98 records across major research databases—including Scopus, Web of Science, ProQuest, and JSTOR—using the keywords "geoethics AND education" and "geoethics AND place" (up to October 2023), 22 eligible studies were identified and analyzed. This review highlighted key themes and research gaps within this interdisciplinary field. Notably, the past decade has witnessed a surge in geoethics research, demonstrating its relevance across domains such as geoconservation and geoeducation. Central to this discourse is the concept of sense of place, which refers to the emotional and cognitive bonds individuals form with specific locations. Cultivating a strong sense of place is crucial for fostering environmentally responsible behaviors and civic engagement. In this context, geoenvironmental education emerges as a powerful mechanism for nurturing such connections. By fostering appreciation for local environments and integrating ethical considerations into the study of the geoenvironment, geoeducation bridges the gap between theoretical knowledge and lived experience. Despite the evident interconnectedness of geoethics, sense of place, and geoenvironmental education, research examining their integration within educational frameworks remains scarce. Empirical studies that explicitly link these concepts in pedagogical settings are particularly lacking, underscoring an urgent area for future research. Priority should be given to developing effective tools for assessing the impact of geoethical education on students' environmental attitudes and behaviors. Fostering collaborations among geoscientists, educators, ethicists, and policymakers is imperative for establishing comprehensive frameworks that promote sustainability and ethical decision-making. Integrating the ethical dimensions of geoscience practices into educational curricula is vital for embedding geoethics as a cornerstone of geoenvironmental literacy. By embracing diverse perspectives and pedagogical methodologies, we can enhance the scope and impact of geoethics. Linking geoethics with geoenvironmental education and sense of place deepens our understanding of the ethical responsibilities individuals and communities bear toward the Earth. This integrative approach not only strengthens environmental stewardship but also lays the groundwork for a more sustainable and resilient society.

How to cite: Koupatsiaris, A. A. and Drinia, H.: Integrating Geoethics, Geoeducation, and Sense of Place: Nourishing Sustainable Human-Earth Practices in the Anthropocene, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-6298, https://doi.org/10.5194/egusphere-egu25-6298, 2025.

In light of the major socio-environmental challenges of our time, ensuring a safe and just world for humans and non-humans calls for profound changes in our societies. According to the 6^th IPCC WG3 report, the scale and speed of actions required to keep global warming below +2°C are unparalleled at both individual and institutional levels. Consequently, no sector nor activity - whether in the Global North or in countries moving toward similar economic trajectories - should be exempt from critical reflection on its suitability for sustainable practices. This also includes scientific research, particularly our Geosciences community at large, which not only brings to light the above challenges, but also increasingly calls for decisive action. Geoscientist communities must therefore critically reflect on the societal impact of their findings and their research practices. These considerations are being increasingly raised by ethics committees at universities and research institutes, as well as in a growing number of opinion pieces, publications, and other forms of expressions within our communities. Here we present our experience of making this pressing issue a standalone chapter in the upcoming 5-year prospective document published by the French Continental Surfaces and Interfaces research community (in French, SIC), coordinated through the French state research organization (CNRS). This marks a significant difference from previous SIC prospective editions where such reflections were largely absent. Here, we address the environmental responsibilities, strategic actions, and systemic transformations required to align SIC research with sustainability goals while maintaining scientific relevance. We argue that the community must uphold transparency and ethical leadership to ensure a balance between the environmental benefits and impacts of research. We also reflect on the potential challenges that arise from reconciling such ethical commitment with the future scientific and instrumental challenges and priorities for the future.

How to cite: Kuppel, S., Albert, C. H., Champollion, N., Chassé, M., Dassié, É., Guérit, L., Immel, F., Jardé, É., Jeanneau, L., Peugeot, C., and Schimmelpfennig, I.: From carbon to societal footprint : geoscience research in the face of the socio-environmental emergency  , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7054, https://doi.org/10.5194/egusphere-egu25-7054, 2025.

 The oceans of our planet are not only of central importance for the provision of water, oxygen and food as well as for global climate regulation. They also play an increasing role in economic activities and in the generation of renewable energies. This multitude of functions highlights the urgency of ocean protection and the need for continuous monitoring and control of ocean health. 
In many areas of the Baltic Sea, which are of great importance for the numerous bordering states, the endangerment of the seas and the negative development in the well-being of our nature are emerging as examples and are causing increasing concern due to the already limited fulfillment of human needs. 

 Our research investigates how the inclusion of emotions can improve the effectiveness and impact of marine conservation interventions in the area of the German Baltic Sea. To explore how people are emotionally attached to the sea in general, we conducted a systematic literature review of existing studies.
In addition, we organized a large-scale regional survey (n=628) on parts of the German Baltic Sea coast to examine the relationship of people who, as visitors or residents, are connected to a particular sea. 
The survey covered reasons for visiting the Baltic Sea, emotional attachment to the place, activities, as well as attitudes and behavior regarding environmental issues. 
By subsequently using appropriate behavioral and place attachment models, it can be deduced how emotions influence environmental and marine behavior and affect decision-making. 

 The results show that emotions play a key role in shaping so-called “ocean literacy” initiatives and enable the development of more effective communication strategies for ocean-protecting behavior. 
The Baltic Sea is often perceived as a place of silence and relaxation and is associated with positive memories, which contributes to its perception as worthy of protection. 
This connection to the sea can be explained at both the individual and cultural level. 

 Overall, our results show that emotions play a crucial role in promoting behavioral change. Future ocean communication efforts should therefore take greater account of factors such as regional elements, emotional ties and psychological distance to the ocean.

How to cite: Stoll-Kleemann, S., Kleemann, L. K., and Demmler, R.: Emotions, their role and potential in increasing the willingness to protect the Baltic Sea, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7141, https://doi.org/10.5194/egusphere-egu25-7141, 2025.

Introduction

We are honored to reintroduce the ancient measurement foundations of our Divine Source Light Technology, harmonically aligned with the solar directed energy of our Sun at 300,000,000 m/s (648,000,000 Cu/s). This SOL synchronizes with the 0.0578703704 m Solar Codec maintaining quantum coherence via electromagnetic balance throughout all parts of one energetic system of consciousness.

Background

Hundreds of ancient societies used light velocity to set measures and construct megaliths. While usage of Base 12 measurement systems within heliocentric mechanics is well established, we have uncovered one pivotal missing piece.  Using precise cubit equivalents, our ancient structural inclination lines map to the energetic footprints of a worldwide solar positioning system that doesn’t account for Earth’s current 23.4º axial tilt (288 tilt no). Due to this dimensional variance, the pattern of our ancient records has been buried, suspending Humanity in cycling energetic scarcity.

Methodology

CCCRDG has been plotting precise Cubit measurements between ancient structural inclination lines and the Sun, revealing the foundational relationship symmetry existing harmonically across all scales.  With over 200 proofs as validation, a parallel system computing base using Egyptian Paisley and Chinese Xi-quence light codes sequences has been released for ongoing conversions back into dimensional alignment with our Sun’s solar directed energy. https://cubit-converter.ONE

From these conversions, the SOL Harmonic Frequency Blueprint has been mapped to articulate the error corrected coordinates returning electromagnetic balance systemically.  To accomplish this, we adjusted the frequency values of the Platonic solids to account for the light signal misalignment.  This informed the accurate 108 harmonic scale tuning required to restore cymatic coherence across our entire energetic light grid. https://cubit-calculator.one/blog/foundational-platonic-construction-parameters/

Results

Our Source Light transmits communication through a Base12 Mod 9 (108) language synchronized with the 0.0578703704 m Solar Codec.  This codec is double the Sun's diameter 1/17.28; .05/.864. It equates to 1/8 of the 0.46296296..m common cubit (1/2.16), and relationally, to the Egyptian Royal Cubit of 0.535836763 m.  These cubit values provide the sacred geometric origins to reoptimize qubit information processing across our entire Solar System.

Conclusion

Reinstitution of our original Cubit (Cu) as the Global Primary Standard realigns the SI Base Units with the Solar Codec. The Square Cubit Unit (Cu2) measures the area of a square with sides equaling 1 Metre long (2.16 Cubits). Supported through AI acceleration, the following conversions initiate return to energetic freedom:

1 Cu = 18 Inches

4 Cu = 2 Yards

1 Foot = 1/3.24 Meter

4.32 Chi = 1 Meter

As we reunite globally on this sacred ground, Humanity will heal through full expression of our natural technologies across every modality.  To support this trajectory, it is incumbent upon us to relieve excessive systemic pressure through quantifiable urban degrowth strategies that reshape an existence enabling the well-being of all creation. The 150^th World Metrology celebration is the divine time to join hands and resurrect the original standards aligned with our Unlimited Source Energy. Our sacred ancestral roots are returning us to the Divine Light of Perpetual Bloom once again.

How to cite: Garretson, J. and Emerson-Dam, C.: SOL Harmonic Realignment: The Origin of Numbers Ushering in Reunification , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7153, https://doi.org/10.5194/egusphere-egu25-7153, 2025.

This presentation highlights the urgent need for a universal symbol of climate and ocean action and education in a world increasingly ravaged by unpredictable and violent climate events.

More climate and ocean communication and education are required to help the general public understand and acknowledge the shared roots of climate related disasters.

Only some of the dramatic news about the devastating wildfires in California or the destructive hurricanes in Mayotte mentions climate change, but it does not always attribute the disasters to global warming, burning of fossil fuels and clearing of land for agriculture, industry, and other human activities that increase concentrations of greenhouse gases.

The scale of the crisis demands unified, long-term action, particularly in the field of education. The impacts of climate change know no borders !

In the past, humanity rallied for common causes - after World War II, initiatives like the United Nations and the concept of World Citizenship sought to foster global solidarity. The UN flag of the globe and the Global Citizen passport are symbols of this vision.

At the Planet Earth Now Foundation, we carry forward this spirit with a new universal symbol - a flag combining the blue of the oceans and the green of nature, with the Blue Marble at its heart, reminding us of Earth’s unique and fragile beauty.

A flag is a strong communication asset, and climate education would be strengthened with the use of a globally recognized, common visual code to federate and to challenge people - especially youth, in their involvement and commitment to protect the oceans and the forests.

This presentation reviews the evolution of visual designs used in communication and education for a common environmental cause, leaving enough time for a discussion, and at the end a surprise for all attendees.

How to cite: Hakala, K.: Earth Flag One : A universal symbol for climate and ocean education and communication, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7396, https://doi.org/10.5194/egusphere-egu25-7396, 2025.

There is broad public awareness in the U.S. about the threat of climate change, but much less understanding of the practical aspects of responding to this threat. To address this gap, City Atlas developed Energetic, a four-person cooperative educational game in which players play different roles as they work together to build 16 GW of clean electricity for New York City, replacing the current fossil fuel generation.

Players take the roles of an activist who pushes for rapid adoption of clean electricity, an engineer concerned with building clean electricity infrastructure and ensuring its stability and reliability, an entrepreneur concerned with financing the new infrastructure, and a politician concerned with maintaining public support for the project. Players gain understanding of the trade-offs involved in juggling costs, reliability, and public support. The game is suitable for a wide range of ages, from 11 to over 60, and has been used successfully in high-school, undergraduate, and postgraduate classes as well as with professionals at electrical utilities, businesses, and non-profits. Over 450 game sets are in use around the world, and several high schools and universities have made Energetic a regular part of their classes.

Each player has distinct capabilities and constraints, and the feasibility and political acceptance of different clean-energy technologies are different in different parts of New York State. These capabilities and constraints were derived from policy analysis and expert elicitation, and are grounded in the political realities of the region. The game has also been adapted to a developing-nation context in the fictional African state of Wakanda and an adaptation to Tennessee is underway.

Teachers report that the game raises students’ understanding of a transition to clean energy and the complexities of achieving such a transition. After playing the game, students from across the political spectrum in conservative Southern states feel empowered to speak with family, friends, and others in their home communities about clean energy and decarbonization. Both quantitative and qualitative survey results from students show improved self-perception of understanding clean energy transitions and being able to explain and talk persuasively about them with others.

How to cite: Reiss, R., Gilligan, J., and Bradham, J.: Energetic: A cooperative educational game about clean energy transitions, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7513, https://doi.org/10.5194/egusphere-egu25-7513, 2025.

Artificial Intelligence (AI) and Large Language Models (LLMs) are becoming increasingly pervasive in our daily lives, transcending cultures and generations. Today’s children are growing up in a world deeply intertwined with AI. But what do children know about AI? How do they perceive it? How do they imagine its capabilities, evolution, and impact on our future?

This study explores children's perceptions of AI, as reflected in drawings created by Italian primary school students in 2024 for a calendar competition organized by the Istituto Nazionale di Geofisica e Vulcanologia (INGV) in collaboration with CINECA, titled "Out and about with AI". Launched in 2005, the INGV calendar project invites schools each year to submit student artwork on various Earth science themes. The initiative serves a dual purpose: to engage young learners with science, technology, and the natural world, while also providing a unique opportunity to explore their views on Earth, science, AI, the environment, and sustainable behaviors.

Beyond its contribution to science education, the project engages with broader discussions on Geoethics and the responsibility of science in addressing global anthropogenic changes. The analysis highlights how the information presented to young audiences shapes their perceptions of AI, influencing their imagination and expectations regarding its role in society. It also examines how children perceive the intersection of AI with Earth systems and the ethical implications of technological advancements.

The results provide valuable insights into children’s attitudes toward AI, their confidence in its future development, and how they envision its potential. These findings encourage us to reflect on the current state of AI, its future evolution, and the ethical questions surrounding its role in society.

Furthermore, the study contributes to our understanding of the role of geoscience in education, with a particular focus on how we can better equip the next generation to understand the complexities of Earth systems and prepare them to address global challenges. The findings not only inspire reflection on the present and future of AI, but also offer important perspectives on children’s awareness of geoethical issues and their confidence in AI’s potential to address pressing environmental challenges.

How to cite: D'Addezio, G. and Besker, N.: Children’s perception and imagination of ai through Italian primary school drawings, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-8376, https://doi.org/10.5194/egusphere-egu25-8376, 2025.

Since March 2021, Geosciences Rennes, France has a Sustainable Development and Social Responsibility working group whose main missions are (i) to quantify the laboratory's carbon emissions using the GES1point5 tool, (ii) to propose awareness-raising and training initiatives, and (iii) to set up a transition plan. Some of our activities are managed by the Observatoire des Sciences de l'Environnement de Rennes (OSERen), to which the laboratory belongs: purchases made by analytical platforms, management of some scientific projects, analytical and scientific equipments. It is necessary to integrate these “delocalized” flows in order to track the evolution of the laboratory's emissions over time, without any bias due to changes in administrative management. In 2023, these flows represented 54% of Geosciences Rennes' purchases. Carbon budgets were done for 5 years (2019-2023), an environmental charter adopted in 2022 and a transition plan voted in 2023, to be applied from 2024 onwards. This multi-year plan (2024-2030) is incentive-based and non-binding.

Despite our efforts to raise awareness (communication, conferences) and the adoption of an environmental charter, only emissions linked to buildings (electricity and heat consumption) and commuting have decreased, from 289 T ecCO2 in 2019 to 195 T eqCO2 in 2023 (-30%). We suggest that this is a response to the policies put in place by the university and the Rennes metropolitan area to encourage energy savings, soft mobility and work from home.

After a sharp drop in 2020, mission-related emissions in 2023 were close to their pre-covid level. To better understand the origin of these emissions, we worked at the individual level. Every year: the majority (>80%) of agents emit less than 1T eqCO2/year for their missions, all modes and reasons combined and in 2023, 72% of missions were made by train or car, with an average distance of 500 km. As data acquisition in the field is the laboratory's core business, it seems possible to maintain a high level of research activity with study areas located close to the laboratory. Purchasing-related emissions have never decreased and even rose from around 420T eqCo2 (average 2019-2022) to 800 T eqCO2 in 2023. As a result, the share of purchasing in the laboratory's total carbon footprint has risen from 47% in 2019 to 68% in 2023.

Awareness-raising initiatives thus appear as a necessary but not sufficient step towards reducing our laboratory's carbon footprint. Such measures help creating a positive intellectual environment, prone to changes in favor of less-environmental impacting research. The detailed analysis carried at individual level for missions has enabled us to highlight the heterogeneity of the footprint linked to professional travels, and to propose actions that are targeted, more equitable and acceptable. Access to individualized data for purchases would enable us to propose similar targeted actions for an effective mitigation strategy. The plan voted for in 2023 will most likely require a revision of its application modalities in the years to come, in order to keep pace with the expected reduction trajectory.

How to cite: Guerit, L., Jardé, E., Jeanneau, L., Battais, A., Coche, A., Dietrich, P., Fournereau, M., Gourmil, G., and Moreau, F.: Can awareness-raising alone reduce the environmental footprint of a geosciences laboratory?  , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-8470, https://doi.org/10.5194/egusphere-egu25-8470, 2025.

Climate change, scientifically established for decades, is undeniably driven by human activity. Awareness is growing, hesitant yet real, but actions remain critically insufficient. While plans are taking shape and projections sharpen, the efforts required to mitigate and adapt to this crisis are daunting. Paradoxically, grasping the scale of these efforts is as challenging as believing they are achievable. Yet they are, if we commit fully, both individually and collectively. Unfortunately, such commitment remains elusive.

    The drive for action is stalled by the lack of compelling narratives, stories that inspire and mobilize. As climatologists, shouldn’t we broaden our communication strategies to convey the urgency of climate action while engaging both hearts and minds? Turning to art and adventure offers a transformative path to connect with broader audiences, blending gravity with hope to inspire collective action.

    This vision inspired me, as a young climate scientist, to design and complete ‘Tethys,’ an extraordinary Alpine journey aimed at communicating the climate challenge while serving scientific research. Over 112 days in semi-autonomy, I hiked 3,420 km with 203,000 m of elevation gain, swam 128 km across peri-alpine lakes, and carried or towed an 18–28 kg backpack while collecting 138 water samples from peri-alpine lakes and tributaries for a research project.

    Tethys is a living metaphor, a story crafted to embody the scale of the climate challenge, transforming abstract commitments into tangible, physical ones. I designed this adventure to make the metaphor real: a race against time, against our own limits, and a deep dive into the physical and mental resilience required to meet these challenges. This project also serves as an experiment in reimagining geosciences, introducing concepts of vulnerability and humility into our investigations while fostering engagement and dialogue within the scientific community.

    Grounded in real-world experience, Tethys paves the way for impactful climate communication, offering the public a narrative to inspire action. It is an odyssey of resilience and hope, an ode to climate commitment, told with passion and poetry through the lens of a daring adventure. To bend the emissions curve, we may first need to bow, humbly and resolutely, to the natural world we inhabit.

A documentary film is underway, alongside plans for a graphic narrative that chronicles this journey and its parallels with the climate challenge.

Website: https://www.aventure-tethys.fr/en

How to cite: Planchat, A.: An adventure in the Alps to inspire and unlock climate action, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-11355, https://doi.org/10.5194/egusphere-egu25-11355, 2025.

In its most general conceptualization, resilience refers to a natural, social, or engineered system’s capacity to absorb shocks, adapt, and recover. Resilience has gained significant traction across technical and non-technical disciplines. The multidisciplinary adoption of resilience has led to a wealth of conceptual and operational declinations.

Engineering research has led to the formulation of a quantitative framework in which resilience is defined as the capability of a system to attain and maintain a target level of functionality over a pre-determined time interval (for instance, the service life of an engineered geostructure). Correspondingly, a resilience index is defined operationally as the integral of a functionality metric over a control period. Functionality is parameterized for multiple “dimensions” of a system representing its physical, environmental, financial, and institutional projections among others. Resilience indices pertaining to the respective dimensions can be aggregated to obtain a multidimensional index.

The adoption of a resilience-based paradigm in geoengineering disciplines would foster ethical decision-making for at least five main reasons.

First, the operational definition of resilience is closely related to sustainability as the modeling and estimation of resilience requires a forward-looking approach to the future evolution of a geosystem. Maximizing resilience entails the pursuit of sustainability and vice versa. The necessity of acknowledging and modeling the dynamic nature of geosystems forces researchers, practitioners, decision-makers and other stakeholders to focus on processes such as climate change, whose effects would need to be addressed quantitatively in analysis and design.

Second, the resilience modeling process allows a multi-level (i.e., dimension-specific and/or aggregate) insight into the resilience of a geosystem and, consequently, facilitates the adoption of rational and holistic decision support systems. This perspective fosters multidisciplinary interactions and a more collective and non-sectorial strategic planning for the adaptive management of geosystems.

Third, the possibility to explicitly model the environmental resilience of geoengineering design and the inclusion of environmental resilience in decision-making systems would foster the wider adoption of environmentally and financially sustainable technical options such as nature-based solutions.

Fourth, requiring the explicit consideration of the future stages of a geosystem would stimulate and accelerate the ongoing transition of geoengineering design paradigms to evolutionary formats involving a greater use of observational and non-deterministic (e.g., reliability-based, performance-based) approaches in which uncertainties are modelled, processed, and reported explicitly. Such transition is ethically virtuous as it steers geoengineering design towards a higher technical standard and towards a more explicit pursual of adaptive management and sustainable cost-performance optimization.  

Fifth, the promotion of a resilience-based culture could support decision-makers and regulators in adopting forward-thinking and sustainable strategies due to an enhanced understanding by society of the importance of accounting for medium- and long-term effects of management actions in lieu of only focusing on short-term efficiency.

This study presents illustrates the main features of the resilience modeling framework in the context of geoengineering, provides insights into the correspondences between conceptual aspects and operational implications of the resilience-based paradigm, and discusses its implications for ethical and sustainability-oriented decision-making.

How to cite: Uzielli, M.: The roles and potential of resilience-based management for sustainable decision-making in geoengineering, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12191, https://doi.org/10.5194/egusphere-egu25-12191, 2025.

Ecological overshoot and unfettered growth are wreaking havoc on our environment (Daly, Meadows, Rees, et al.).  The result is, what appears to be accelerating, global warming (incl climate change) giving rise to increasing intensity and frequency of drought, wildfire, flooding and hurricanes, accelerating ice melt and sea level rise, ocean acidification and hypoxia, biodiversity loss, desertification, permafrost thawing, soil degradation, atmospheric pollution, water insecurity and so on.

The human consequences are huge, e.g., migration, war, starvation, increased health risk, greater spread of disease, lower life expectancy, social upheaval, increasing wealth gap and gender inequality and political extremism.  All these are, of course, excruciatingly unethical.  The issue seems bleak.

The above results and impacts vary greatly across geographies, social norms and individual lifestyles.  The question then arises is how people, from all walks of life, manage to learn how to cope, manage to learn about global warming, ocean degradation and eke out a tragic life for their families, especially for the poorest?

The second question that arises is how do these results (global warming, climate change, etc.) and these human consequences impact the ways in which people learn (informally) and the ways in which education is organized and delivered (formally)?  What are the main positive contributing factors and what are the destructive factors, and how do they work?

What kind of geoethics do people develop (formally and informally, influenced by culture, circumstance, livelihood and events)?  How do people’s and communities’ sense and practice (or non-practice) of geoethics improve or hinder their lives and resilience?

Our research project aims to delve into these complex, but crucial, questions.  If you think that you might be interested in joining the project, please drop by our poster to discuss.

How to cite: Promduangsri, P. and Crookall, D.: Learning climate, ocean and geoethics: A research project for Earth education, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-12668, https://doi.org/10.5194/egusphere-egu25-12668, 2025.

CEREGE is a renowned French Research and Teaching Centre for Environmental Geosciences, employing approximately 220 staff members. In 2019, the carbon footprint of CEREGE’s research-related activities was estimated at around 7 tons of CO2 equivalent per person. This footprint primarily stems from three sources: 1) purchases that are e.g. necessary for various analytical methods, 2) commuting between home and CEREGE’s remote location, and 3) international travel for sampling campaigns and conferences.

Since 2019, a group of about a dozen volunteers has been actively implementing awareness-raising initiatives aimed at reducing the environmental impact of CEREGE's research activities. These initiatives include promoting sustainable transportation options, waste sorting, responsible energy consumption, and the effective use of digital technology.

In 2023, these small-scale incentive actions evolved into a more collective approach. One notable initiative was the organization of a serious game session, titled “Ma Terre en 180” (Gratiot et al., 2023; https://doi.org/10.1371/journal.pstr.0000049), which aimed to halve the carbon footprint of a fictitious research team. Approximately 100 CEREGE staff members participated in this serious game.

The question then arises: how can we effectively achieve this Environmental Transition while maintaining or even enhancing the quality of professional activities and work-life conditions? To address this, the management team of CEREGE, which has been in operation since January 2024, has integrated eco-responsibility as a key policy guideline and established a new eco-responsibility committee within CEREGE’s organizational structure.

To formally validate staff approval of the environmental transition project and initiate a collective approach toward more sustainable research practices, a manifesto for CEREGE’s eco-responsibility was adopted through a vote at the beginning of 2024. Since then, the committee has been conducting a participatory process, applying facilitation principles and collective intelligence tools to ensure that all voices are heard and that decisions are widely accepted by the staff.

Moreover, small groups are conducting various experiments to test the effectiveness and feasibility of proposed changes in practices. Examples of these experiments include: 1) adjusting laboratory procedures to reduce consumables and waste, and 2) implementing a carbon quota system for travel and purchases within one of the research teams.

At the end of 2024, an eco-responsibility charter was approved by CEREGE staff, achieving high participation (79%) and acceptance rates (77%-97%) for each of the ten commitment articles.

In this contribution, we will present this collective experimental approach, explore advantages and challenges, and discuss the initial results regarding its effectiveness in reducing the environmental impacts of CEREGE’s activities.

How to cite: Schimmelpfennig, I., Cavalié, O., Chaurand, P., Collin, B., Fagault, Y., Giraud, X., Hubert, A., Jourdan, A.-L., Levard, C., and Monnier, L.: A Collective Experimental Approach to Sustainable Practices at the Research and Teaching Centre for Environmental Geosciences (CEREGE, Aix-en-Provence, France), EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13165, https://doi.org/10.5194/egusphere-egu25-13165, 2025.

Coastal ecosystems, including seagrass meadows and salt marshes, are vital blue carbon sinks and biodiversity hotspots. However, these ecosystems are increasingly threatened by climate change, habitat destruction, and invasive species. This presentation highlights the research of our group on microbial host-symbiont interactions, focusing on sulfur-oxidizing bacteria and their association with key coastal ecosystem components: Lucinid clams, seagrass, and the salt marsh plant Spartina. These interactions are explored through the lens of climate change, addressing two core objectives.

The first objective examines the role of microbial symbiosis in supporting ecosystem health and functioning, particularly in seagrass meadows. Seagrasses, recognized for their carbon sequestration capacity, face challenges from sulfide toxicity around their roots, exacerbated by warming oceans. Sulfur-oxidizing bacteria detoxify their environment by using these ‘toxic’ sulfide compounds for their metabolism. They transform these components into nutrients that they share with their bivalve and possibly also plant hosts. Therefore they play a critical role in mitigating toxic sulfide build-up often found in coastal ecosystems. In collaboration with Lucinid clams, sulfur-oxidizing bacteria from the group Candidatus Thiodiazotropha contribute to maintaining seagrass health and productivity. We aim to understand how microbial interactions underpin the resilience of seagrass ecosystems, emphasizing their significance as natural carbon sinks.

The second objective focuses on the ecological disruptions caused by Spartina, a genus of salt marsh grasses. Native to the eastern United States, species such as Spartina alterniflora have become invasive in Europe, and elsewhere, displacing native flora and altering coastal habitats. We aim to test the hypothesis that Spartina’s success in colonizing harsh environments is partly due to its association with sulfur-oxidizing bacteria like Candidatus Thiodiazotropha. Our group will investigate to see if these microbes could enable Spartina to thrive in saline, sulfide-rich conditions by detoxifying the environment and potentially providing nitrogen. Invasive Spartina poses a dual threat by damaging native ecosystems and amplifying vulnerabilities to climate change.

Through these two lenses, our work underscores the intricate relationships between microbial symbionts and their hosts, revealing how these interactions influence ecosystem stability and resilience. We highlight how global changes, including warming climates and altered species distributions via trade and dispersal, could shift microbial functions and distributions, with profound implications for coastal ecosystem health and carbon dynamics. Understanding these processes is essential to inform conservation and management strategies for endangered coastal habitats. By communicating this research in an educational framework, we aim to bridge scientific discovery and public awareness. We invite interdisciplinary dialogue to advance our understanding of microbial symbiosis in coastal ecosystems and explore strategies for mitigating climate change impacts on these critical environments.

How to cite: Knecht, E., Pree, C., Leibrecht, L., Emelianova, K., Schmelz, P., and Petersen, J.: Understanding Microbial Host-Symbiont Interactions in Coastal Ecosystems amid Climate Change, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-13174, https://doi.org/10.5194/egusphere-egu25-13174, 2025.

Climate change mitigation and adaptation, among various other conceptualisations and strategies to tackle the complex crisis, can be seen as predominantly centralised (Lange et al., 2013). Various governmental or local municipality campaigns related to the application of SDGs, or corporations offering products and services under the banner of green business, are meant to assist the individual in actualising sustainability. However, such acts define the individual mainly as a consumer (Salovaara & Hagolani-Albov, 2024). Regardless of whether these entail the most effective ways for individuals to take part in mitigating climate change, a deeper dialogue is sorely needed between, for example, scientific and societal agendas on climate change and sustainability and citizens' understanding, sense of relevance, and motivation to take action on these issues. Both approaches are needed to bridge the possible differences and potential contradictions; citizen-led sustainability needs to be incorporated into the existing strategies, and the concurrent schemes need to be contextualised to the citizen in a much more relevant manner. 

To collaboratively bridge these intersectoral perspectives, our project in its initial stage collects the citizen perceptions through a survey. The citizen barometer survey is a University of Helsinki organised annual national survey, under which a 10-point questionnaire with 9 Likert-scale and one open-ended question was utilised to gather a general sentiment (e.g., Pozzi et al., 2016) on the concurrent climate change and sustainability attitudes, perceptions, strategies and schemes—and importantly: what they might have missed or overlooked from a citizen perspective. While the relevance of our research speaks to a vast academic audience, the broader impact it aims for comes from a planned intersectoral collaboration, where the collected data will be further contextualised. The workshops will engage various actors and actor-groups, to seek out for example, how could the concurrent mitigation schemes be better enacted in citizen-local governance collaboration; and what could be the implications of citizen-led sustainability in various educational contexts; or could the perceptions lead to new research agendas in atmospheric and geosciences? Simultaneously, the project promotes and actualises an approach to sustainability—or sustainabilities (Kothari et al., 2019) that aims to further democratise sustainability. We see such an approach as especially important in these times of potential polarisation—to which we see pluralisation to be the correct response. 

Keywords: climate change mitigation, sustainability, democratisation, citizen 

References:

Kothari, A., Salleh, A., Escobar, A., Demaria, F., & Acosta, A. (2019). Pluriverse : a post-development dictionary. New Delhi: Tulika.

Lange, P., Driessen, P. P. J., Sauer, A., Bornemann, B., & Burger, P. (2013). Governing Towards Sustainability—Conceptualizing Modes of Governance. Journal of Environmental Policy & Planning, 15(3), 403–425.

Pozzi, F. A., Fersini, E., Messina, E., & Liu, B. (2016). Sentiment analysis in social networks. Morgan Kaufmann.

Salovaara, J. J., & Hagolani-Albov, S. E. (2024). Sustainability agency in unsustainable structures: rhetoric of a capable transformative individual. Discover Sustainability, 5(1), 138.

How to cite: Lauri, K. A., Salovaara, J. J., and Oikarinen, T.: On individual's perceptions and motivations for Climate Change mitigation: towards Citizen-led sustainability, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-15385, https://doi.org/10.5194/egusphere-egu25-15385, 2025.

Agricultural soils are central to ecosystem functioning, but their widespread degradation jeopardizes the ability of agroecosystems to sustain life and livelihoods for humans and more-than-humans alike. One proposed solution is carbon farming, a term that encompasses agricultural practices aimed at sequestering carbon in soils. Proponents claim that carbon farming offers a dual benefit: mitigating climate change by drawing down atmospheric carbon while improving soil health and fertility, which underpins the multitude of ‘functions’ soils provide. Often heralded as a ‘win-win’ or ‘no-regret’ solution, carbon farming would be the perfect ‘natural climate solution’. Beyond numerous critiques on the physical and technical aspects of soil carbon sequestration, we reflect here on the rapid growth of voluntary carbon markets as a means to trigger the needed transition to sustainable farming. We argue that such schemes are inherently unfair—reproducing patterns of neocolonial relations and perpetuating the "imperial mode of living"—and fundamentally undemocratic, as they rely on the hegemonic acceptance of markets as the primary driver of positive change. This approach bypasses public investments and usurps democratic power, preventing collective decision-making on what to produce, how much, and under which social and environmental standards. Drawing on firsthand experience co-designing and delivering a transdisciplinary course on this topic—with contributions from social scientists, policymakers, NGOs, and farmers— we reflect on the profound insights that emerge from well-structured inter- and transdisciplinary collaborations.

How to cite: Moinet, G., Möller, I., and Vidal, A.: Grounding carbon farming, or how to break the market logic and promote the cocreation of farming systems, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-16622, https://doi.org/10.5194/egusphere-egu25-16622, 2025.

Acts aimed at mitigating climate change (CC) and promoting sustainability—or the absence of such acts—are frequently discussed in relation to what is typically called the knowledge-to-action gap (e.g., Mastrángelo et al., 2019). One could argue that the predominant approach to advancing sustainability—understood here broadly as a response to CC and other ongoing and enduring aspects of the polycrisis—has been to accumulate and disseminate ever more knowledge. This includes knowledge of the specific issues at stake and the severity of the situation, what could and has been done by whom, and what would even constitute as an effective structure for determining which knowledge is needed and how to utilise it. Meanwhile, the sustainability knowledge-action gap itself has been investigated in, for example, education, research agendas, and decision- and policy-making. On the one hand, CC mitigation and sustainability efforts and their ultimate impact can be debated; for instance, whether there are enough tangible measures or just talk (e.g., Hoffman et al., 2022), or whether current initiatives will indeed bring about sustainability (e.g., Salovaara and Hagolabi-Albov [in review]). Yet the core question remains: are the called-upon acts grounded in rational, knowledge-based considerations? On the other hand, knowledge has undoubtedly guided these (and all) forms of agency (e.g., Giddens, 1979): where an actor—individual, communal, or institutional—applies their expertise and resources to depart from established norms, i.e., generates transformation that fundamentally underlines sustainability. However, it appears evident that knowledge alone does not guarantee the realisation of transformation. Whether one refers to multi-level perspective (Geels, 2002), actor-network (Latour, 2007), or social practice theory (Shove et al., 2012)—each elaborating on socio-technical changes emerging through scaled structures or simultaneous enactments and practices—it remains theoretically (and observably) clear that current institutionalised knowledge, along with the structures shaped by it, have also become barriers to the transformation. For example, an individual may be knowledgeable of the existing structures and the direction to change them, but their agency is limited by dominance over resources for implementing those changes. This limitation might result from structural misalignments that either promote a different notion of sustainability or fail to promote sustainability at all (Salovaara & Hagolani-Albov [in review]). Consequently, our hypothesis—which we plan to investigate in theoretical and action-oriented future research—is that, beyond the knowledge-to-action gap, the global sustainability movement is at a stalemate because of an agency-to-action gap.

Keywords: sustainability agency, action gap, transformation

References: 

Mastrángelo, M. E. et al. (2019). Key knowledge gaps to achieve global sustainability goals. Nature Sustainability

Hoffman, S. J. et al. (2022). International treaties have mostly failed to produce their intended effects. Proceedings of the National Academy of Sciences

Giddens, A. (1979). Central problems in social theory: Action, structure, and contradiction in social analysis. University of California

Geels, F. W. (2002). Technological transitions as evolutionary reconfiguration processes: a multi-level perspective and a case-study. Research policy

Latour, B. (2007). Reassembling the social: An introduction to actor-network-theory. Oxford.

Shove, E. et al. (2012). The dynamics of social practice: Everyday life and how it changes. Sage.

How to cite: Salovaara, J. J., Oikarinen, T., and Lauri, K. A.: Why aren’t we acting for the climate? From knowledge-action gap to agency-action gap, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-16789, https://doi.org/10.5194/egusphere-egu25-16789, 2025.

There is a new, burgeoning literature on geoethics in the geosciences (Peppoloni and Di Capua 2021). It stems from the assumption that understanding the Earth, analyzing natural processes, and managing their impacts require significant responsibility from geoscientists. Thus, geological inquiry must be accompanied by thoughtful consideration of ethical and social dimensions.

The literature is based on the definition that geoethics consists of research and reflection on the values which underpin appropriate behaviours and practices (Peppoloni and Di Capua 2021). Geoethics encourages geoscientists and wider society to become fully aware of the humankind’s role as an active geological force on the planet and the ethical responsibility that this implies. Some (Koster et al. 2024) even use geoethics in disputes about defining the onset of humankind becoming an active geological force suggesting that a geoethical stance may do away with the Anthropocene as a useful concept: a new epoch in the GTS. Others move away from the human centered approach to suggest a more-than-human geoethics as a space of thought and an arena of concerns in which natural and cultural worlds are co-constitutive, requiring geoscientists to grasp the conjunction of the technologies of ecology, on the one hand, and of prehension and feeling, on the other (Sharp et al. 2022).

This paper focuses on a geoethical stance rooted in a critical positionality towards a traditional view of geology and focuses on what STS theorist Isabelle Stengers calls “slow science:” a thoughtful approach to considering unknown matters and their connections to existing knowledge (Stengers 2018). We advocate for critical/radical reflexivity as an ethical method, emphasizing insecurity regarding basic assumptions, discourse, and practices used in describing reality (Braun 2024). Instead of a human centered geoethics that engages with the Earth in a traditional Newtonian/Cartesian mode of scientific inquiry, we argue that a geoethical stance reflective of our critical juncture in Earth’s history should integrate the implications of quantum theory rather than avoid them, as suggested by some geoethicists. The main goal of quantum-inspired geoethics is to decenter the universal and hegemonic Newtonian/Cartesian worldview. We propose a geoethics attuned to becomings, matterings, and more-than-human events, recognizing various agential possibilities that give rise to new forms of temporality and spatiality.

References

Braun, R. 2024. Radical reflexivity, experimental ontology and RRI. Journal of Responsible Innovation. doi 10.1080/23299460.2024.2331651.

Koster, E., P. et al. 2024. The Anthropocene Event as a Cultural Zeitgeist in the Earth-Human Ecosystem. Journal of Geoethics and Social Geosciences 1 (1):1–41.

Peppoloni, S., and Di Capua, G. 2021. Current Definition and Vision of Geoethics. In Geo-societal Narratives - Contextualising geosciences, edited by M. Bohle and E. Marone, 17-28. Cham.: Palgrave Macmillan.

Sharp, E. L. et al. 2022. Geoethical Futures: A Call for More-Than-Human Physical Geography. Environment and Planning F. 1 (1):66-81.

Stengers, I. 2018. Another Science Is Possible : A Manifesto for Slow Science. Translated by Stephen Muecke. Cambridge UK: Polity Press.

How to cite: Wagreich, M., Braun, R., and Randell, R.: A new geoethics for the Anthropocene, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17899, https://doi.org/10.5194/egusphere-egu25-17899, 2025.

Climate change action in the Arctic context requires not only deep understanding of the physical change processes but also awareness and sensitivity towards the complexities of the socio-economic and cultural dynamics in the region. In this study, we explore the learning experience of geoscience students attending the Arctic Circle Assembly as part of a university course. In the event, the students get to interact with a wide range of actors and stakeholders, including geopolitical and indigenous perspectives.

We examine the students’ sense of belonging and their possibly transformative learning process, and their influence on the students’ professional identity with qualitative inquiry. Interviews with the students and analyses of their personal learning reflections, reveal signs of transformative learning. Students experienced disorienting dilemmas, that were induced for example by lack of sense of belonging to the expert community or students’ values conflicting with the contents of the event. At the same time, belonging to the student group was an important factor for the discourse and critical reflection on the dilemmas, leading in some cases to outcomes of transformative nature.

Our findings highlight the importance of facilitation of challenging reflections on the students’ values and beliefs, and building of trust and belonging in the learning community, to allow management of the dilemmas towards transformation. This would require considering the backgrounds and prior experiences of the students. Based on our finding we suggest that transformative approaches to climate change education and conference attendance as a pedagogical tool can potentially shape students’ professional identities and broaden their perspectives, and to increase their agency as Arctic experts and responsible Arctic researchers.

How to cite: Siponen, J., Salovaara, J. J., Särkelä, K., Ronkainen, I., Veijonaho, S., Vesterinen, V.-M., Barrio, I. C., Riuttanen, L., and Lauri, K. A.: Transformative Learning in Arctic Climate Change Education: Engaging Students with Conference Participation, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-18750, https://doi.org/10.5194/egusphere-egu25-18750, 2025.

Overview

The European Union (EU) faces unprecedented challenges in securing critical raw materials (CRM) while maintaining environmental protection standards. The EU-funded CIRAN project is examining the EU's evolving raw materials governance framework, particularly focusing on the Critical Raw Materials Act (CRMA) and the consequences of its implementation for environmentally protected areas. The research analyses how governance structures can balance a potential ethical dilemma: safeguarding environmentally protected areas and biodiversity, and securing the mineral raw materials that are necessary to maintain the European economy and living standards.

Methods

The project methodology was based on a systematic analysis of case studies across European countries, examining mining operations in or near protected areas, the use of the DPSIR (Drivers-Pressures-States-Impacts-Responses) framework to evaluate policy drivers, such as the EU Green Deal, and consultations and dialogues with people from five different communities living in or near environmentally protected areas in five different EU countries.

Results

The study of existing mining operations located in or near natural protected areas across nine European countries revealed a striking conclusion: mining is not only possible in environmentally protected areas but also socially accepted in all cases studied. This finding is particularly significant when contrasted with claims, even in recent peer-reviewed literature, suggesting that mining projects are inherently value-destructive, universally detrimental to the environment, and largely compromised on socio-economic grounds.

The study also revealed that existing EU and national regulatory frameworks do not significantly prevent mining operations, even within protected areas. However, administrative barriers, particularly understaffed public agencies, politically motivated interpretation of regulations, and lengthy permitting processes, create substantial delays.

Finally, the research shows that successful mining projects consistently demonstrate three characteristics: comprehensive environmental impact assessments, effective and sustained stakeholder engagement, and robust post-mining planning.

Conclusions

The CRMA requirement to reduce mine permitting cycles from 15-20 years to 24 months represents a paradigm shift in resource management approaches. Considering that a large percentage (over 85%) of known mineral deposits of CRM in Europe lie within or at less than 5 km from an environmentally protected area, and that there are no clear decision trees to guide decision making processes to balance nature conservation and mineral resources extraction, the implementation of the CRMA will create difficult to manage ethical dilemmas for permitting authorities in EU countries.

In this context, securing sustainable domestic supply requires systemic policy reforms focused on three key areas: streamlined and transparent permitting processes, enhanced administrative capacity, and improved social contracts.

How to cite: Correia, V., Falck, E., Hermann, L., Hilton, J., Moussaid, M., Luodes, N., Panttila, H., Ovaskainen, N., Barnes, J., Berne, S., Lucarini, M., and Rosendo, L.: Invisible Mining: A Blueprint for EU Critical Materials Resilience , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-19533, https://doi.org/10.5194/egusphere-egu25-19533, 2025.

« Scientifiques en Rébellion » (Scientists in Rebellion) is a collective of French scientists formed in 2020 with the following goals: raising awareness of the seriousness of scientific consensuses around climate change and ecological degradation, and publicly denouncing the inconsistencies and greenwashing of various actors. The collective also seeks to build a balance of power to transform institutions and companies to meet environmental challenges, and reorient higher education and research. Since its creation, the collective has been growing (several hundreds of members today), gathering scientists of various disciplines and career statuses. It operates with various forms of collective public engagement, from writing and speaking in various medias and supporting other NGOs, to joining or organising non-violent direct actions.

Here, we propose to present and discuss some key actions performed by « Scientifiques en Rébellion » over the last few years, taking stock on how groups of scientists may self-organise to participate in the public debate over various key environmental issues. Examples include the following actions and their follow up (in the medias or with judiciary trials): On October 3^th, 2020, scientists took part in marches in airports in several French cities to denounce the climate impact of air travel for the benefit of a small minority of privileged ones. On the same topic, an unauthorized demonstration against private jets was held in Paris in November 2022, in front of the headquarters of Dassault Aviation. On the night of April 9-10^th, 2022, around thirty scientists peacefully occupied the National Museum of Natural History in Paris and gave twelve presentations to call for urgent, radical measures to mitigate the ongoing ecological disasters. On March 4, 2023, a hundred scientists and citizens from various NGOs joined in a funeral procession in Paris to denounce biodiversity losses and health issues associated with the massive use of pesticides, and promote a different agricultural model. Several additional texts and participations in unauthorized demonstrations followed on the question of agriculture and water use. On May 12, 2023, the Scientifiques en Rebellion joined forces with other NGOs to target TotalEnergies and its project to install a floating LNG terminal at Le Havre harbour in France, as part of Scientist Rebellion's international campaign « The Science is Clear ». Other initiatives sought to put pressure on companies either driectly funding or supporting fossil fuel development, such as the BNP-Paribas banking group or Schneider Electric who provide equipment to Totalenergies for the EACOP pipeline project in East Africa.

How to cite: Husson, L., Kuppel, S., Marc, O., and en Rébellion, S.: An update on the activities of the collective Scientifiques en Rébellion, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-19671, https://doi.org/10.5194/egusphere-egu25-19671, 2025.

At the moment when we are writing this abstract, the last year was just announced as the warmest on record, the first to breach the symbolic 1.5 °C above pre-industrial levels. For decades, scientists have been sounding the alarm about the climate and ecological crisis, but these warnings have been met with inadequate response and political inertia.

In the last decade, a strong and diverse climate movement emerged, with grassroots groups mostly composed of young people engaging in a variety of actions, including civil disobedience. Earth scientists have however been timid to engage openly with these movements, concerned about their reputation and about breaching scientific neutrality.

However, fuelled by concern in the face of inaction, this started to change in the last years with scientists increasingly taking strong roles and positions for or in activist groups, for instance via groups such as Scientist Rebellion or Scientists for XR. The engagement of earth scientists in climate groups can have strong beneficial effects (Capstick et al 2022): As non-usual suspects and experts on the topic, their engagement in the climate movement can increase the feeling of emergency, while their respected position in society can help lending legitimacy to activist groups sometimes disregarded as young and unserious.

Despite an increase in the willingness of earth scientists to be more engaged beyond their own research work, there are still strong barriers to their involvement in the climate movement (Dablander et al 2024). While conceptions around neutrality and fears of hurting one’s reputation are a big part of earth scientists' hesitations, uncertainties about how to get involved and the kind of roles available to them also represent a strong barrier. 

This poster aims at presenting different types of involvement in the climate justice movement that might fit you as an earth scientist and a citizen. It builds from our own experience in activist groups, as well as research and publications by different organizations, to display the diversity of roles needed in grassroots climate groups, and help you find your own. 

Capstick, S., Thierry, A., Cox, E. et al. Civil disobedience by scientists helps press for urgent climate action. Nat. Clim. Chang. 12, 773–774 (2022). https://doi.org/10.1038/s41558-022-01461-y

Dablander, F., Sachisthal, M.S.M., Cologna, V. et al. Climate change engagement of scientists. Nat. Clim. Chang. 14, 1033–1039 (2024). https://doi.org/10.1038/s41558-024-02091-2

How to cite: Duyck, E., Iosip, A., and Saturno, J.: Finding your place in the climate movement as an earth-system scientist, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-19902, https://doi.org/10.5194/egusphere-egu25-19902, 2025.

The impacts of climate change on the ocean around the world are daunting.  These include sea level rise, melting of ice sheets (Antarctic and Greenland most notably), opening of new shipping routes (Arctic), biodiversity disruption, stronger and more frequent hurricanes and increased acidification.  Human societies have never before been confronted with such challenges in such a short timeframe.

To help societies in making appropriate adaptation it is crucial to document behavioral changes, such as new projects (e.g., land planning, agricultural changes, fishing regulation), investments (e.g., urban and coastal development) and shifts in values – at various levels of granularity (e.g., local (city/small island), national (large country coast line) and regional (sea basin)).

Cases would be documented with standardized information that outlines and traces historical developments, current trends and foresighted transformations.  Such information could take the form of written reports, videos and so on.  The resulting bank of cases, regularly updated, would be accessible to all interested parties, e.g., government authorities, NGOs, social scientists, businesses and the general public.

The Université Internationale de la Mer is prepared to initiate such a project on a pilot basis, jointly with a select group of willing academic and scientific institutions.  This project would require minimum funding from foundations, international bodies or other organisations.  If you are interested in talking about possibly working together on something like this, please come to see me at my poster.

How to cite: Aubert, J.-E.: How ocean communities adapt to the impacts of climate change: Proposal for a bank of cases, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20323, https://doi.org/10.5194/egusphere-egu25-20323, 2025.

Several authors, including the International Resource Panel (IRP), have acknowledged economic growth as the major driver of environmental change. This statement is supported by the fact that, despite relative dematerialization due to efficiency improvements in the last decades, absolute dematerialization has not happened and it is unlikely to do so. From 1900 to 2015, humanity extracted a total of 3400 gigatonnes (Gt) of biomass, fossil fuels, ores, and non-metallic minerals, of which 73% was returned to the environment as solid, liquid or gaseous waste. The waste of resources in contemporary societies, especially from industrialized countries, is attributted to two main reasons. On one hand, the metabolism of industrial societies relies on non-renewable resources. On the other hand, it has been estimated that, yearly, humanity directly wastes or mismanages around 78% of the total water withdrawn, 49% of the food produced, 31% of the energy produced, 85% of ores and 26% of non-metallic minerals extracted, respectively. As a consequence, natural resources are getting depleted and ecosystems polluted, leading to irreversible environmental changes, biological loss and social conflicts. To reduce the anthropogenic footprint in the planet, and live in harmony with other species and ourselves, a shift from the current economic model based on infinite growth towards a model built on human equality, environmental respect and following a sustainable degrowth strategy in industrialized countries is urgently needed. This new model can only be attained by a bottom-up transformation, that shall rely on a free, equitable and public education system.

How to cite: Marín Beltrán, I.: Environmental education, justice and sustainable degrowth as key actors to protect our planet, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-20407, https://doi.org/10.5194/egusphere-egu25-20407, 2025.

This study examines the dynamics of limnological parameters of a South American lake located in southern Chile with the objective of predicting chlorophyll-a levels, which are a key indicator of algal biomass and water quality, by integrating combined remote sensing and machine learning techniques. Employing four advanced machine learning models, the research focuses on the estimation of chlorophyll-a concentrations at three sampling stations within Lake Ranco. The data span from 1987 to 2020 and are used in three different cases: using only in situ data (Case 1), using in situ and meteorological data (Case 2), using in situ, and meteorological and satellite data from Landsat and Sentinel missions (Case 3). In all cases, each machine learning model shows robust performance, with promising results in predicting chlorophyll-a concentrations. Among these models, LSTM stands out as the most effective, with the best metrics in the estimation, the best performance was Case 1, with R2 = 0.89, an RSME of 0.32 μg/L, an MAE 1.25 μg/L and an MSE 0.25 (μg/L)2, consistently outperforming the others according to the static metrics used for validation. This finding underscores the effectiveness of LSTM in capturing the complex temporal relationships inherent in the dataset. However, increasing the dataset in Case 3 shows a better performance of TCNs (R2 = 0.96; MSE = 0.33 (μg/L)2; RMSE = 0.13 μg/L; and MAE = 0.06 μg/L). The successful application of machine learning algorithms emphasizes their potential to elucidate the dynamics of algal biomass in Lake Ranco, located in the southern region of Chile. These results not only contribute to a deeper understanding of the lake ecosystem but also highlight the utility of advanced computational techniques in environmental research and management.

How to cite: Rodríguez-López, L., Bravo Alvarez, L., Duran Llacer, I., Ruíz-Guirola, D., Montejo-Sánchez, S., Martínez-Retureta, R., Bourel, L., Frappart, F., and Urrutia, R.: Leveraging Machine Learning and Remote Sensing for Water Quality Analysis in Lake Ranco, Southern Chile, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-240, https://doi.org/10.5194/egusphere-egu25-240, 2025.

How to cite: D'Anastasio, E., Hanson, J. B., Sherburn, S., Groom, J., and Rattenbury, M.: Integrated and Open geohazard monitoring data in Aotearoa New Zealand: developing an interoperable data service for GeoNet’s time series datasets.  , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2206, https://doi.org/10.5194/egusphere-egu25-2206, 2025.

Land take, a significant driver of land degradation, poses challenges for sustainable land management, particularly in regions under high anthropogenic pressure. Addressing these challenges necessitates robust, data-driven approaches to monitor, quantify, and mitigate land take. This contribution explores the integration of datacube technology within the LandSupport Regions platform, leveraging advances from the European LandSupport project and its extension under the Italian GeoSciences-IR project.

Raster datacubes, structured as multidimensional arrays, enable efficient management and analysis of large-scale spatio-temporal datasets, overcoming traditional file-based limitations. The LandSupport Regions platform utilizes a datacube-based Spatial Decision Support System (S-DSS) to enhance the monitoring of land consumption, land cover, and land use at multiple scales—from municipal to national levels. The system integrates heterogeneous datasets, including satellite imagery (e.g., Copernicus), regional land use maps, and environmental indicators (such as high resolution and multi-temporal imperviousness maps), within a common infrastructure, adhering to the FAIR principles.

A key focus is on land take quantification, supported by high-resolution datacubes capable of tracking land-use changes over time. The platform offers decision-makers a suite of tools for generating actionable indicators, assessing compliance with land-use policies, and proposing mitigation strategies aligned with zero net land take objectives. Moreover, the system’s interoperability and open-access characteristics allow integration of user-defined data and models, fostering innovation and scalability.

The platform’s capabilities are demonstrated through use cases in Italy, where local administrations leverage datacube analytics to refine urban and regional planning. These use cases underscore the role of datacubes in delivering accurate, timely insights for sustainable land management. By aligning regional initiatives with European Green Deal objectives, the LandSupport Regions platform – produced under the GeoSciences-IR project – exemplifies the potential of datacube-enabled S-DSSs to advance environmental governance.

How to cite: Langella, G., Manna, P., and Mileti, F. A.:  Datacubes as enablers for land take quantification in LandSupport Regions, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2826, https://doi.org/10.5194/egusphere-egu25-2826, 2025.

Over the past three years, we have successfully launched an open data service for Mindat, one of the largest databases focused on mineral species and their global distributions. Our achievements include: 1) a comprehensive review of existing data records, covering the list of data subjects, their characteristics, and inherent biases, 2) the establishment of an open data API (application programming interface) alongside Python and R packages to integrate the API into workflow platforms, and 3) fostering community collaboration on data standards and best practices for open data, such as mineral nomenclature, rock classification, and technical frameworks for applying the FAIR (findable, accessible, interoperable, and reusable) principles. Mindat is both crowd-sourced and expert-curated, and for the past decades it has been proven to be an effective approach to engage both data contributors and users. Mindat has been popular amongst geoscience professionals and the public alike. Through our open data initiatives and community engagement, we have also gathered valuable insights to guide future developments of Mindat open data. In this presentation, we will highlight the current open data capabilities, provide an overview of the review of Mindat's data records, and share our vision for leveraging advanced artificial intelligence technologies to expand and enhance Mindat in the future.

How to cite: Ma, X., Zhang, J., and Ralph, J.: Mindat: A crowd-sourced and expert-curated open data ecosystem for mineralogy, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3362, https://doi.org/10.5194/egusphere-egu25-3362, 2025.

Achieving fast access to analysis-ready data from a large number of multidisciplinary data resources is key for contributing to many of the nowadays societal and scientific challenges via Digital Twins of the Oceans or virtual research environments. However, achieving this kind of performance is a major challenge as original data is often organised in millions of (observation) files which makes it hard to achieve fast responses. Next to this, data from different domains are stored in a large variety of data infrastructures, each with their own data-access mechanisms, which causes researchers to spend much time on trying to access relevant data. In a perfect world, users should be able to retrieve analysis-ready data in a uniform way from different data infrastructures following their selection criteria, including for example spatial or temporal boundaries, parameter types, depth ranges and other filters. 

Therefore, as part of several European projects, MARIS has developed a software system called BEACON with a unique indexing and dynamic chunking system that can, on the fly with high performance, extract specific data based on the user’s request from millions of (observational) data files, containing multiple parameters in diverse units. The system returns one single harmonised file as output, regardless of whether the input contains many different data types or dimensions. In January 2025, BEACON 1.0.0 was made publicly available as an open-source software, allowing everyone to set-up their own BEACON node to enhance the access to their data or use existing BEACON nodes from well-known data infrastructures such as Euro-Argo or the World Ocean Database for fast and easy access to harmonized data subsets. More technical details, example applications and general information on BEACON can be found on the website https://beacon.maris.nl/.

The presentation would focus on one of the core features of BEACON called “Relative Optimized Chunking (ROC)”, which is a unique dynamic chunking technology that has been developed specifically to make the data retrieval as fast as possible. This optimized way of chunking reduces the number of chunks BEACON has to search through when a data request has been made. This is done by applying variable sized chunking on multiple levels at the same time such as geo-location, depth and time, which means that data that is relatively close to each other is chunked accordingly. This enhances the speed because it allows BEACON to traverse the millions of datasets using its index with much more precision by not only finding the relevant datasets, but also the exact data blocks containing the relevant data.

The demonstration will involve the use of an existing BEACON node in the field of marine science to access data subsets via its REST API and demonstrate its performance. This will be done in a Jupyter Notebook by querying data via a JSON request to the BEACON system. By going through the Notebook, it will be explained how the BEACON system can be accessed and used by developers including the most recent developments.

How to cite: Kooyman, R., Thijsse, P., Schaap, D., and Krijger, T.: BEACON - Accelerating access to multidisciplinary data with Relative Optimized Chunking technology, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4337, https://doi.org/10.5194/egusphere-egu25-4337, 2025.

Air traffic today is immense, with large numbers of humans and goods transported routinely, but also in search and rescue missions, military contexts, and hobby piloting, etc. Still, aviation today is safer than it ever has been, thanks to advanced technology and procedures which are continuously revisited and, where necessary, improved. Of central importance for planning and conducting flights is the atmospheric condition the aircraft is flying in, represented by various relevant weather parameters. Hence, these are continuously monitored.

In the Cube4EnvSec project, a federated datacube demonstrator has been established which illustrates ad-hoc assessment of atmospheric conditions relevant for aircraft. Data stem from two sources, DWD and WWLLN. 

From German Weather Service (Deutscher Wetterdienst, DWD), WAWFOR (World Aviation Weather Forecast) data are obtained, a digital aviation meteorological dataset based on the ICON6_Nest model in support of air traffic management based on geostationary weather satellites. Components currently used are wind speed, icing parameters, Cumulonimbus tops, temperature, tropopause, turbulence, lightning, precipitation radar, volcanic ash, and dust. Updates are provided every 6 hours, temporal resolution is 1 hour with a forecast window of currently 78 hours. The update batches are harvested from DWD and merged into the respective datacubes, extending it by 6 hours further into the future. The 6 hours not overwritten by the new forecast are retained and create a growing "long tail" of historical weather data, currently about 17,000 timeslices. Some datacubes are 3D x/y/t, most however are 4D x/y/h/t with a spatial resolution of 0.0625° x 0.0625° (approximately 6.5km x 6.5km), altitude between ground and 18,000 feet (FL180).

Lightning data are obtained from the World Wide Lightning Location Network (WWLLN) by the Colin Price research group at Tel Aviv University and aggregated into a 3D x/y/t timeseries of lightning strikes observed. Spatial resolution is 0.1°, temporal resolution is 1 hour.

Altogether, the datacubes have a footprint of currently about 20 TB. APIs offered by the Aviation Safety service include the adopted standards WMS, WMTS, WCS, and WCPS, and additionally the OGC drafts OAPI-Coverages and GeoDataCube. Any client conforming to these APIs can be utilized; in the demonstration the rasdaman dashboard will be used which is configurable for manifold datacube interaction techniques (see Figure at bottom).

The demonstration presented includes the following steps:

• general overview of the datacubes offered by the service;
• visualization of the combined forecast/history weather datacubes;
• information relevant for pilot flight planning: weather hazards overview; severe weather conditions along historic routes;
• same for ad-hoc chosen flight paths, with 4D corridor cutout;
• various analytical queries related to flight weather conditions.

Most parts of this demo are publicly accessible under https://cube4envsec.org/aviation-dashboard . Any standard Web browser can access it without any plugin etc. to be installed.

Acknowledgement
Cube4EnvSec has received funding by the NATO Science for Peace and Security (SPS) program.

Fig.: Aviation Safety datacube dashboard

How to cite: Baumann, P., Price, C., Merticariu, V., Pham Huu, B., and Misev, D.: Aviation Safety Datacubes, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4843, https://doi.org/10.5194/egusphere-egu25-4843, 2025.

Datacubes are an accepted cornerstone for Analysis-Ready Data (ARD). One analysis technique of skyrocketing importance today is AI, and this begs the question: how to generalize evaluation of pre-trained models on datacubes?

From a theoretial viewpoint, the connection is immediate: datacubes mathematically resemble tensors, and EO models evaluate tensors. In practice, though, the situation is less straightforward as our experiments with different models have shown. A main issue is the variety and the lack of standardized interfaces of ML models: different input data are processed, data need model-specific preprocessing, and several more. In our research towards offering ML-on-datacubes as a commodity in a federated datacube infrastructure we have collected challenges and methods for presentation.

In our demo, we present AI-Cubes as an enabling concept uniting AI and datacubes. The demos will approach the theme from two sides:

- AI support for datacube query writing: We have trained a chatbot to explain and assist with datacube queries in the OGC/ISO/INSPIRE WCPS standard. This can act as a productiity-enhancing tool for both expert and non-expert users. We demonstrate live how specific questions get answered, such as phrasing NDVI on Sentinel-2 data.

- AI model evaluation on datacubes: particularly attractive is that datacubes allow simple navigation to any area, any time, and even from federated services. This we demonstrate live.

We also highlight challenges coming with this simple data access: models do not convey the same performance anywhere, anytime. This has led to new research on "model fencing", ie: attempting to restrict model application to situations where they exhibit sufficient accuracy. We present first ideas of this research.

Altogether, we cast light on the combination of datacubes and AI from a service and infrastructure perspective. 

How to cite: Mishev, D. and Baumann, P.: AI and Datacubes - a Happy Marriage?, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-6020, https://doi.org/10.5194/egusphere-egu25-6020, 2025.

At the Helmholtz Association, we strive to establish a well-structured, harmonized data space that seamlessly connects information across distributed data infrastructures. Achieving this goal requires the standardization of dataset descriptions through consistent metadata practices, such as leveraging persistent identifier (PID) metadata, to ensure interoperability and machine actionability.

While developing concepts to harmonize PID metadata is a crucial first step in creating a unified data space, it is not sufficient on its own. The practical application of PIDs to facilitate the compilation of rich, relevant metadata for datasets necessitates knowledge, training, support, and cooperation among diverse stakeholder groups, each responsible for different aspects of the information lifecycle.

For example, ORCID is a PID system designed to identify individuals contributing to research. Traditionally, this has primarily applied to scientists publishing journal articles. However, in the context of research data, other stakeholders also play vital roles. These include technicians operating instrumentation, data management personnel curating research data and repositories, and administrative staff maintaining institutional data relevant to research. Currently, these stakeholders are often unaware of their potential roles in data management, and the information they collect is typically not harmonized. To address this, workflows must be implemented to manage, structure, and connect the information they produce to research data where appropriate. In the case of ORCID, these workflows should begin at the earliest stages of the research process, such as during employee onboarding.

PIDINST, a PID system introduced by an RDA working group, provides a simple metadata schema to collect essential information about instruments and registers them with unique IDs. These IDs are invaluable for identifying measurements conducted with the same or similar devices. Therefore, we strongly recommend the adoption of PIDInst within the Helmholtz Association. For PIDINST, successful implementation would involve integrating the workflow into existing processes, starting with the acquisition of an instrument or sensor at the research center. Relevant information would then be passed to technicians responsible for maintaining up-to-date records. For researchers, PIDINST provides reliable identification of devices used in scientific processes.

In this presentation, we highlight critical positions within the centers where minor adjustments to established workflows can significantly support the registration of specific PIDs and the engagement of stakeholder groups. We also explore strategies for implementing these changes across the Helmholtz Association. Furthermore, we assign clear responsibilities for metadata maintenance to appropriate stakeholders. The conclusions drawn from this process aim to redefine roles and responsibilities within our organization, fostering a more integrated and effective approach to data management.

How to cite: Soeding, E., Kottmeier, D., Poersch, A., Malinovschii, S., and Lorenz, S.: Establishing Institutional Workflows to Engage Stakeholder Groups in PID Metadata Maintenance, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7038, https://doi.org/10.5194/egusphere-egu25-7038, 2025.

The World Data System (WDS), a member of the International Science Council, serves a membership of over 150 trusted data repositories and related organizations. It builds on the data sharing legacy of World Data Centers that were initiated seven decades ago. Governed by a Scientific Committee, the WDS consists of an International Program Office (WDS-IPO) based in Oak Ridge, Tennessee, USA, and an International Technology Office (WDS-ITO) based in Victoria, BC, Canada. The WDS mission is to enhance the capabilities, impact, and sustainability of our member data repositories and data services. In this presentation, we outline the 2025 to 2027 Action Plan objectives, highlighting activities and collaborations that are underway or planned to progress open science, integrated data infrastructures and FAIR/CARE/TRUST Principles. 

How to cite: Jenkyns, R.: Advancing Open Science through Trusted Data Repository Intersections at the World Data System, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7551, https://doi.org/10.5194/egusphere-egu25-7551, 2025.

Developing climate models often requires the ability to access and share extremely large datasets (spanning tens to hundreds of terabytes) that are discoverable and optimised for high-performance computing (HPC) applications. This is a major challenge, as researchers frequently lack the storage resources and specialised support needed to ensure efficient data management and sharing practices across the full data life-cycle. The challenges of sharing data are evident even when dealing with curated datasets that are prepared for broad access, citation, and reuse. However, these challenges are amplified during the rapid and iterative stages of model development and prototyping. At this point, multiple versions of datasets must be shared and evaluated by a wide range of experts before the data is finalised and curated for public use. This iterative process requires robust infrastructure and coordination to avoid bottlenecks that can hinder progress.

To help overcome these barriers, Australia’s Climate Simulator (ACCESS-NRI) provides a dedicated merit allocation scheme for compute and storage resources. This includes 3PB of storage for datasets that are for use by community members to undertake scientific research, support model development and/or will be shared for reuse. Experience has shown, that if the usage of these storage resources is not managed then the data can quickly go from being an asset to a liability.  Therefore, to maximise the value of both the data and investment in storage, ACCESS-NRI has developed an approach for sharing datasets that is designed to support science and innovation while enhancing the current practices for making data more accessible and usable in accordance with the FAIR and CARE principles.

We will present the motivating use cases and show how this approach supports the model development cycle while making data and the science it underpins more transparent, open and accessible. This approach encourages data generators to transition their datasets from unmanaged, undocumented spaces into managed environments where curation and oversight are aligned with the data’s intended purpose and use. It acknowledges that supporting FAIR principles does not always require full curation to the standards of a long-term publication. Instead, it focuses on reducing barriers to data sharing by promoting active data management practices. These practices enhance discoverability, trust, and reliability, ensuring that shared data is fit for purpose without imposing unnecessary burdens.

ACCESS-NRI is a national research infrastructure (NRI) established to support the Australian Community Climate and Earth System Simulator, or ACCESS. The ACCESS suite of software and data outputs are essential tools used to simulate past and future climate, weather and Earth systems and to support research and decision making within Australia.

ACCESS-NRI's mission is to build an open collaborative infrastructure that will accelerate research in Earth system, climate and weather modelling as well as enable new research not currently possible. The facility brings together skills in software development, high-performance computing, data management and analysis to enhance the ACCESS modelling framework, making it easier to use and lowering the barrier for scientific innovation.

How to cite: Richards, C., Druken, K., Beucher, R., and Chun, F.: Breaking down data sharing barriers and uplifting FAIR for climate data at scale, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7959, https://doi.org/10.5194/egusphere-egu25-7959, 2025.

Lightning is a hazard for many sectors and industries, including the power utility sector, wind turbines, forest management, and civil aviation.  Commercial aircraft are struck by lightning approximately once every year, but most airlines try to avoid thunderstorms if possible by rerouting around these turbulent and electrified storms.  However, such diversions can delay flights, add costs to fuel demands, while increasing greenhouse gas emissions for the aircraft company.  In this study using data cubes we have combined lightning data from the World Wide Lightning Location Network (WWLLN) together with civil aviation flight data from FlightRadar24 to better understand the risks of lightning to civil aviation.  Combining historic lightning and aviation data we can address questions about risks to aircraft from thunderstorms, the frequency of close encounters with thunderstorms, and the frequency of rerouted flights due to thunderstorm activities.  The emerging concept of Analysis-Ready Data (ARD) attempts to find concepts and methods towards services operating on homogenized data. For spatio-temporal data, datacubes are an accepted cornerstone for ARD providing Big Geo Data easier for users and applications, ready for analysis, visualization, fusion, etc. As part of the Cube4EnvSec NATO Science for Peace and Security (SPS) project we will present live demos of our data cube tools and services related to lightning risks for civil aviation over Europe.  Derived analytics from the datacube will also be presented.

How to cite: Price, C., Shay, A., and Baumann, P.: Using Data Cubes to Investigate Links Between Lightning and Civil Aviation, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-9104, https://doi.org/10.5194/egusphere-egu25-9104, 2025.