Content:

GI – Geosciences Instrumentation & Data Systems

GI1.1 – Open session on geoscience instrumentation and methods

EGU2020-4991 | Displays | GI1.1

Polarisation Based Interferometric Optical Fibre Geophone Sensor Designed for High Resolution Seismic Detection

James Jena, Shukree Wassin, Lucian Bezuidenhout, Moctar Doucouré, and Tim Gibbon

Geophones are essential for monitoring seismic activity to study the structure of the earth for ground surveys, mineral exploration and early warning detection of geo-hazards. Traditional electromagnetic based geophones are fairly effective in detecting micro-seismic activity and ambient signals. Their induction based mass-spring sensing mechanism can however be somewhat performance limiting. Limitations include reduced frequency response, resolution and recovery times between successive activities. This ultimately impacts the sensitivity and performance of the device. In this paper, we present a novel optical fiber geophone sensor that addresses these issues through superior sensitivity, performance and ease of deployment. Our optical fiber geophone is polarization based, single ended and operates on a Michelson interferometric principle. Tests were performed to compare the performance of our optical fibre geophone to that of a commercial electromagnetic geophone. Vibrations of varying magnitude were remotely generated at 1.065 m from both devices. Sensor signal responses to disturbances of energy lower than 1.1 mJ were plotted and analysed. Observed traces from the sensor responses were compared, showing that the fiber geophone has significantly shorter response and recovery times. As a result, the resolution between rapidly succeeding signals is considerably greater for the optical fiber geophone. Sensitivity plots of the amplitude response to the vibration energy gave a scatter of points depicting a higher degree of precision and accuracy for the fiber geophone. Response slopes of 11.70 a.u/mJ and 10.31 a.u/mJ respectively were obtained for the sensitivity of the optical fiber geophone versus the electromagnetic geophone. While the typical spurious frequency is close to 150 Hz for the traditional geophone, the bandwidth of the optical fiber geophone is an order of magnitude greater.

Keywords- Geophone, Optical fibre, Polarisation, Michelson Interferometer

How to cite: Jena, J., Wassin, S., Bezuidenhout, L., Doucouré, M., and Gibbon, T.: Polarisation Based Interferometric Optical Fibre Geophone Sensor Designed for High Resolution Seismic Detection, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4991, https://doi.org/10.5194/egusphere-egu2020-4991, 2020.

The chemical, mineralogical and textural investigation of drill cores demands objective and repeatable information unaffected by the human bias to be able to correlate significant features across drillcores. Imaging Laser induced Breakdown Spektroscopy (LIBS) can be applied to large scales at high spatial resolution in relatively short times to obtain detailed chemical, mineralogical and textural information with a minimum of sample preparation. The application of the Spectral Angle Mapper (SAM) algorithm for supervised classification of the LIBS hyperspectral data cubes provides a relatively fast, but easy to handle tool to visualize and quantify variations in the chemical, mineralogical composition of complex ores from the sub-millimetre to the metre scale. The information derived offers novel and barely investigated interpretation opportunities in a very detailed manner which directly can be used for exploration purposes. The investigated Merensky Reef is about 1 m thick. It consists of pegmatoidal pyroxenite framed by the lower and upper thin chromitite seams. The Merensky Reef is one major ore body out of three for platinum-group elements (PGE) within the Bushveld Igneous Complex which is the world’s largest known layered intrusion and largest PGE resource on Earth   Detailed LIBS-based imaging measurements with 200µm spotsize were accompanied by space-resolved reference measurements based on SEM/MLA (4µm) and µ-EDXRF (20µm), as well as bulk chemical analyses for multiple core slices. The SAM algorithm was applied for classification of hyperspectral LIBS images as being sensitive for differences in mineral chemistry. Focus was put on the pre-processing of LIBS spectra prior to SAM classification, on the development of the spectral library, and on the validation of the classified data. The SAM classification algorithm, which is solely based on ratios between spectral intensities, was found insensitive to normal shot-to-shot plasma variations and to chemically induced matrix effects. However, the algorithm may become inaccurate at low signal to noise ratios, at the border between different mineral grains (mixed spectra), or when classifying chemically similar phases such as pyrite and pyrrhotite. The extent of mixed spectra depends both on the size of the mineral grains as well as on the spot size of the LIBS laser. The SAM algorithm was successfully applied for classification of several base metal sulphides, rock-forming minerals, accessory minerals, as well as several mixed phases representing the main borders between different mineral grains. The obtained classified LIBS image images the spatial distribution of the different phases, which corresponds very well to the reference measurements based on highly space-resolved  EDXRF and SEM/MLA mineral distribution maps. The investigated core piece highlights the extremely heterogeneous distribution of e.g. the sulphide phases. The LIBS-SAM classification image was used to estimate metal concentrations based on point counting. The applicability has been explored for Cu, Ni, S, and Cr. This approach, when applied on sufficiently large surfaces, enables quantification of well-defined mineral phases, as well as the possible detection of trace elements (e.g. Pt, Pd) that occur in very small nuggets.

How to cite: Rammlmair, D. and Meima, J.: Quantitative mineralogy of chromite ore based on imaging Laser Induced Breakdown Spectroscopy and Spectral Angle Mapper Classification Algorithm, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19373, https://doi.org/10.5194/egusphere-egu2020-19373, 2020.

EGU2020-1503 | Displays | GI1.1

Monitoring African Bush Elephants with the OSOP Raspberry Shake and Boom

Oliver Lamb, Michael Shore, Jonathan Lees, and Stephen Lee

In terms of terrestrial animal communication, elephants are especially noteworthy because they have been documented to produce some of the loudest sounds at frequencies between 10-35 Hz. Their vocalisations, or ‘rumbles’, with fundamental frequencies in the infrasonic range (≤ 20 Hz) can have amplitudes as high as 117 dB. Here we present our efforts to evaluate the performance of the Raspberry Shake and Boom, a low-cost seismic and acoustic sensor, for identifying and monitoring the movements of African Bush Elephants (Loxodonta africana). The test area was the Adventures with Elephants elephant reserve in South Africa which includes a herd of 7 elephants (3 females, 2 males, and 2 juveniles). Within the reserve we deployed a local network of 5 Raspberry Shake and Boom units in October 2019 in order to record seismo-acoustic waves generated by the herd. The network also included other seismic and acoustic sensors of different sensitivities which were used to assess the performance Raspberry Shake and Boom units. We show that the Raspberry Shake and Boom units performed well during the deployment, with clear recordings of elephant movement and rumbles. The acoustic data also suggests that we may be able to discriminate between individual elephants due to the distinct frequencies of their rumbles. This presentation will provide general information on the potential use of low-cost sensor units for the purpose of unobtrusively monitoring vulnerable wildlife such as elephants.

How to cite: Lamb, O., Shore, M., Lees, J., and Lee, S.: Monitoring African Bush Elephants with the OSOP Raspberry Shake and Boom, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1503, https://doi.org/10.5194/egusphere-egu2020-1503, 2020.

EGU2020-7426 | Displays | GI1.1 | Highlight | Christiaan Huygens Medal Lecture

Multi-length probes in GPR and TDR data

Raffaele Persico

I will expose some possibilities regarding the use of metallic probes of different lengths in GPR and TDR prospecting. With regard to GPR, multi-length probes are dipole-like antennas whose length can be changed by means of switches. The switches can be implemented with PIN diodes, and can act as electronic “knifes”. Therefore, they allow to cut (switched off) or prolong (switched on) the branches of a couple of antennas, and this allows to have more couples of equivalent antennas making use of a unique physical couple of antennas. This allows to contain the size of the system. In particular, a reconfigurable prototypal stepped frequency GPR system was developed within the project AITECH (http://www.aitechnet.com/ibam.html)  and was tested in several cases histories  [1-3]. Within this reconfigurable GPR, it is also possible to reconfigure vs. the frequency the integration times of the harmonic tones constituting the radiated signal. This feature allows to reject external electromagnetic interferences without filtering the spectrum of the received signal [4] and without increasing the radiated power.

With regard to TDR measurements, a multi-length probe consists of a TDR device where the rods (in multi-wire version) or the length of internal and external conductor (in coaxial version) can be changed. This can be useful for the measurements of electromagnetic characteristics of a material under test (MUT), in particular its dielectric permittivity and magnetic permeability, both meant in general as complex quantities. Multi-length TDR measurements allow to acquire independent information on the MUT even at single frequency, and this can be of interest in the case of dispersive materials [5-6].

Acknowledgements

I collaborated with several colleagues about the above issues. To list of them would be long, so I will just mention their affiliations: Florence Engineering srl, University of Florence, IDSGeoradar srl, 3d-radar Ltd, Institute for Archaeological and Monumental Heritage IBAM-CNR, University of Bari, University of Malta. Finally, a particular mention is deserved for the Cost Action TU1208.

References

[1] R. Persico, M. Ciminale, L. Matera, A new reconfigurable stepped frequency GPR system, possibilities and issues; applications to two different Cultural Heritage Resources, Near Surface Geophysics, 12, 793-801, 2014.

[2] L. Matera, M. Noviello, M. Ciminale, R. Persico, Integration of multisensor data: an experiment in the archaeological park of Egnazia (Apulia, Southern Italy), Near Surface Geophysics, 13, 613-621, 2015.

[3] R. Persico, S. D'Amico, L. Matera, E. Colica, C. De, Giorgio, A. Alescio, C. Sammut and P. Galea, P. (2019), GPR Investigations at St John's Co‐Cathedral in Valletta, Near Surface Geophysics, 17, 213-229, 2019.

[4] R. Persico, D. Dei, F. Parrini, L. Matera, Mitigation of narrow band interferences by means of a reconfigurable stepped frequency GPR system, Radio Science, 51, 2016.

[5] R. Persico, M. Pieraccini, Measurement of dielectric and magnetic properties of Materials by means of a TDR probe, Near Surface Geophysics, 16,1-9, 2018.

[6] R. Persico, I. Farhat, L. Farrugia, S. d’Amico, C. Sammut, An innovative use of TDR probes: First numerical validations with a coaxial cable, Journal of Environmental & Engineering Geophysics, 23, 437-442, 2018.

How to cite: Persico, R.: Multi-length probes in GPR and TDR data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7426, https://doi.org/10.5194/egusphere-egu2020-7426, 2020.

EGU2020-7227 | Displays | GI1.1

Induction Magnetometer transported by UAV for power lines monitoring

Valery Korepanov, Vira Pronenko, Fedir Dudkin, and Andrii Prystai

Assessment of a power lines condition is an important task for all countries. It includes GPS mapping of the: 1) wire breaks; 2) places of the increased current leakage, for example corona detection; 3) degree of wires sagging between power line towers; 4) location and conditions of the power line towers; 5) vegetation encroachment along a power line corridor.  Considering that power line currents, including leakage currents, create strong magnetic field, use of magnetometers in the range from DC to sound frequencies for the solution of tasks 1-4 is highly prospective. At the same time, it is possible the control of the vegetation critical proximity to a power line adjacent zone by the increased leakage current (threats of the increased leakage current or breakdown to a tree crown). Thus the task 5 also can be solved.

The goal of the present report is to introduce the new design of miniature low-weight three-component sensor for measurement of alternative vector magnetic field onboard UAV – induction magnetometer (IM) - with autonomous system including two-component tiltmeter and GPS antenna inside in order to obtain precise measurement timing, UAV coordinates and altitude during movement. These data are stored in the SD memory card. Construction details, tests results and technical specifications of this IM for are presented.

How to cite: Korepanov, V., Pronenko, V., Dudkin, F., and Prystai, A.: Induction Magnetometer transported by UAV for power lines monitoring, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7227, https://doi.org/10.5194/egusphere-egu2020-7227, 2020.

EGU2020-4885 | Displays | GI1.1

The attenuation of coda waves in the RIF area.

Oussama Arab, mimoun harnafi, Ibrahim ouchen, roumaissae azguet, younes El Fellah, and sebbani Jamal

This work is presenting the attenuation of coda waves in the Rif region. Using 15 broadband stations, we investigate the attenuation of coda waves utilizing the single backscattering model of aki and chouet. We collect 70 local earthquakes during 2014 for five laps time window 20, 30, 40, 50 and 60s. We computed the quality factors at different central frequencies band on which start from 1.5, 3.0, 6.0, 9.0, 12.0 and 18.0 Hz. For 40s window length, the Qc gives average value for the whole zone of about 128,51 for 1.5 Hz and 993,44 for 18 Hz band frequencies. We observed a clear dependency between the quality factor and the frequency. Also, we have found that this region is tectonic active comparing to previous studies around the world.

How to cite: Arab, O., harnafi, M., ouchen, I., azguet, R., El Fellah, Y., and Jamal, S.: The attenuation of coda waves in the RIF area., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4885, https://doi.org/10.5194/egusphere-egu2020-4885, 2020.

EGU2020-407 | Displays | GI1.1

Cost-effective recreational-grade single beam echosounder with side scan sonar system in imaging bubbly coastal submarine groundwater discharge

Mary Rose Gabuyo, Fernando Siringan, Keanu Jershon Sarmiento, and Paul Caesar Flores

Submarine groundwater discharge (SGD) is any direct flow of fluid across the seafloor, which forms bubbly or leaky springs and seeps from the intertidal zone to the deep sea. SGDs can significantly alter physico-chemical conditions of seepage zones. Identifying and mapping SGD is crucial to further recognize its influence in both marine and terrestrial ecosystems. However, mapping this phenomenon has been a continuing challenge, mainly due to the difficulty in its detection and quantification. This study explores the capability and applicability of an inexpensive, commercially available, recreational-grade combination of depth meter and side scan sonar system to image different types and identify point sources of coastal SGDs. Standard and systematic methodologies for efficient imaging and processing were established. The utility of the recreational-grade system was assessed and validated using a research-grade side scan sonar. SCUBA diving and CTD casting were conducted for ground-truthing and further characterization. Lower frequency sonars (83/200 kHz) showed more distinct acoustic signatures of discrete and dispersed bubbly SGDs, than the higher frequency system (455 kHz and 780 kHz research-grade unit). Sonar images showed that SGD plumes can be indicated by near seafloor to midwater cloud-like features. Spring-type SGDs tend to form cloud features with a funnel-shaped morphology. In sites where SGDs are dispersed, the acoustic signature is a curtain-like cloud, with higher bubble density in the upper water column. This is consistent with diver-based observation of increasing bubble sizes (<1 mm to ~30 mm) from point source to water surface. CTD casts indicate that the SGDs have recirculated seawater, with increasing temperature and salinity with depth. In the assessment of system and data processing requirements, and costing, a recreational-grade unit provides a good alternative for coastal SGD works.

How to cite: Gabuyo, M. R., Siringan, F., Sarmiento, K. J., and Flores, P. C.: Cost-effective recreational-grade single beam echosounder with side scan sonar system in imaging bubbly coastal submarine groundwater discharge, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-407, https://doi.org/10.5194/egusphere-egu2020-407, 2020.

EGU2020-21715 | Displays | GI1.1

Benchmark of multiple geophysics tools to study the voids in the upper levels of a decommissioned iron mine

Simon Bouteille, Adnand Bitri, Michel Dietz, and Julien Gance

Absorption muon imaging is a technique that can measure density variations underground down to a few hundred meters. Then, it can prove to be useful in a mining environment: to help assess the ore bodies volumes and/or to monitor the underground for natural hazards that can happen at the surface because of the mining exploitation. Here we report the result of an experiment designed to test the capabilities and resolution power of a cosmic muon measurement in a mining environment compared to other standard geophysics tools: gravimetry and seismic studies. It consists of three independent measurement of a subset of the decommissioned iron mine of May-sur-Orne (France). The first one was made using a 50x50cm² micromegas based muon telescope installed at the deepest non-submerged level (50m underground) during 3 months. The second one is a gravimetry survey of the surface area inside the muon telescope acceptance cone. And the third one is a study of refracted and reflected seismic waves along a single line above the muon telescope location. The investigation volume was chosen because of the presence of surface risks (neighborhood), the unknown of some uncharted volume and the presence of an ore storage volume of several meter cubed that was used during the mine exploitation and which filling state is unknown.

The data analysis showed that while muon tomography is able to detect the negative density anomaly of the storage volume, the gravimetry measurement is not sensible to it. However, the seismic study was able to detect the volume as well and its location and extension is compatible with the muon measurement.

How to cite: Bouteille, S., Bitri, A., Dietz, M., and Gance, J.: Benchmark of multiple geophysics tools to study the voids in the upper levels of a decommissioned iron mine, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21715, https://doi.org/10.5194/egusphere-egu2020-21715, 2020.

EGU2020-18524 | Displays | GI1.1

Building a perfomance protocol of a low cost seismograph

Markos Avlonitis, Spiridon Krokidis, Ioannis Vlachos, Vasileios Karakostas, and Anastasios Kostoglou

The low cost seismograph under study consists of low cost open source hardware and software microprocessor boards (Arduino Uno R3  and Raspberry Pi 3 B+ ), customized low noise design signal amplifiers, low power dissipation sophisticated power supply, two (2) kinds of earth ground shaking sensors a) Ceramic Accelerometer with cutoff frequency fc=0.15Hz and b) moving coil geophone with cutoff frequency fc=4.5Hz. The signals from the two sensors are amplified independently, while an active second order low-pass anti-alias filter and an 8th order active low-pass anti-alias filter have been used. Finally, a low-cost microprocessor board is responsible for digitizing the analog data from the amplified signal of the sensors with a frequency sampling rate of 345Hz. The aim of the present work is to design and test a systemic protocol in order to evaluate the performance of the proposed low cost seismograph for monitoring local to regional seismicity and micro seismicity. The proposed low-cost system was installed in an area of high seismic activity (Lefkada Island – Village Evgiros) and the recordings are transmitted to the database continuously from the day of its installation up today. Thus have create an amount of data for more than 280 days and all of those data have been stored to our database. Collocated with a high resolution 24 bits digitizer equipped with a broad band seismometer give us the opportunity to compare the recordings. To this end, a testing list of 15 local events has been created with different epicenters and magnitudes. For each event the recording signals have been analyzed in terms of a) power spectrum analysis, b) estimation of first arrival times of both P and S waves, c) signal amplitudes and d) earthquake duration. The choice of those specific measures was done in order to evaluate the performance of the low-cost seismograph in terms of certain seismic parameters such as magnitude, epicenter and source properties. Initial results in terms of the proposed protocol are also presented showing an adequate performance of the propose low cost seismograph.

 

Keywords:
low-cost instruments, Ionian islands, performance protocol

Acknowledgements
«Telemachus – Innovative Seismic Risk Management Operational System of the Ionian Islands» which is part of the Operational Program «Ionian Islands 2014-2020» and is co-financed by the European Regional Development Fund (ERDF) (National Strategic Reference Framework - NSRF 2014-20).

How to cite: Avlonitis, M., Krokidis, S., Vlachos, I., Karakostas, V., and Kostoglou, A.: Building a perfomance protocol of a low cost seismograph, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18524, https://doi.org/10.5194/egusphere-egu2020-18524, 2020.

EGU2020-19522 | Displays | GI1.1

Simplifying Instrument Pools: The Next Generation Family of Smart Instrumentation.

Sally Mohr, Marie Balon, Sofia Filippi, Neil Watkiss, and Phil Hill

As the community further expands their scope of study, pushing into different sub-disciplines and evermore challenging environments, the need for dynamic and highly adaptable systems grows. One of the challenges for instrument pool managers is finding a system that can cater for a wide range of possible use scenarios.

This is where traditional broadband, force-feedback sensors meet their limitations: with constrained frequency responses and sensitivities, they tend to target very narrow applications offering limited flexibility. When managing a pool of instruments, this translates into increasing pressure to acquire multiple units within different instrument ranges to meet the requirements for each specific application. This in turn leads to complex pool maintenance and may require operators to use unfamiliar instruments if their first choice is being used owing to a reduced number of instruments for each application within the pool.

Güralp’s 35 years’ experience in working with major national instrument pools revealed the necessity to develop flexible, easy-to use systems that could fit a wider scope of applications. This has led to a new, highly versatile smart sensor that supports extensive user configuration and ultra-wide tilt ranges.

The new sensor has a configurable long period corner allowing for rapid deployment in a range of environments: the 1s mode ensures the sensor settles quickly for rapid response purposes, and the 120s mode is ideally suited for long period observation.

The group of products that use this technology deliver high sensor reliability, sophisticated tools for ease of instrument and data management as well as industry standard data formats. The sensors have been integrated into various instruments: the Certimus for surface and shallow burial, the Radian for deeper postholes and boreholes, and the Fortimus for strong-motion applications.  The same philosophy also brought about Aquarius, an Ocean Bottom Seismometer that utilises the same sensor technology for the benefit of OBS pools.

This family of just four instruments covers the vast majority of seismic monitoring requirements. They represent Güralp’s solution to make instrument pool management easier and more affordable.

 

 

How to cite: Mohr, S., Balon, M., Filippi, S., Watkiss, N., and Hill, P.: Simplifying Instrument Pools: The Next Generation Family of Smart Instrumentation., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19522, https://doi.org/10.5194/egusphere-egu2020-19522, 2020.

Exploitation of super-critical water from deep geothermal resources can potentially give a 5-10 fold increase in the power output per well. Such an improvement represents a significant reduction in investment costs for deep geothermal energy projects, thus improving their competiveness.

In the previous European Horizon2020 DESCRAMBLE (Drilling in dEep, Super-CRitical AMBients of continental Europe) project it was demonstrated drilling of a deep geothermal well with super-critical conditions (>375°C, >220 bar) by extending an existing well in Larderello, Italy to a depth of around 4km. As state-of-the-art electronic logging tools could not operate reliably at these conditions, DESCRAMBLE developed and tested a novel pressure and temperature logging tool for these supercritical conditions. Target specification for the slickline operated tool was 8 hours logging operation time at 450°C/450 bar, limited by the critical temperature for the available battery technology used for the application. During testing in the supercritical well in Larderello, Italy in 2017, the tool recorded a maximum well temperature of 443.6°C.

The instrument developed in the DESCRAMBLE project, although being state-of-the-art in its performance, was costly and advanced in addition to having a larger outer diameter than desired in for example slim-well applications. Therefore, there is a need for a simpler, lower cost version of this tool with a smaller outer diameter.

The tool being developed, based on the H2020 DESCRAMBLE project, consists of off-the-shelf high temperature electronics, sensors and batteries shielded from the environment by a heat and pressure shield (Dewar). The target specification for the tool is 600°C/500Bar, with a shorter operational time than the DESCRAMBLE tool.

In this work, we describe the tool requirements and discuss the design choices made regarding mechanical parts, seals, electronics platform, sensors, and available battery technology. 3D CAD drawings and simulations of the thermal performance of the tool will be presented, as well as preliminary test results of the electronic platform combined with the sensors and batteries. Production and testing of the physical tool will not be within the scope of the project.

 

How to cite: Hamremoen Røed, M.: Development of a Low Cost Novel PT Logging Tool for High Temperature Operation (600°C), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21488, https://doi.org/10.5194/egusphere-egu2020-21488, 2020.

GI1.2 – COST Actions in geosciences: breakthrough ideas, research activities and results

EGU2020-22484 | Displays | GI1.2 | Highlight

Creating Impact through COST Action networks

Deniz Karaca

The European Cooperation in Science and Technology (COST) has a very important role in fostering the establishment of scientific excellence in many fields such as: Geoscience, Planetary and Environment. Over the years, COST Actions have contributed to European competitiveness through their many contributions to standardisation bodies, the small to medium enterprises originating from COST networks and the transfer of results to the European industry.

A series of COST Actions in the field of Meteorology developed global data transfer standards on the basis of infra-networks in collaboration with the World Meteorological Organization advantaging the competitiveness of the industrial participation. Such achievements include harmonisation of UV-index, developing operational programmes, services, networks and phenological responses to climate on a Pan-European Scale and were recognised by the Intergovernmental Panel on Climate Change.  European Centre for Medium-Range Weather Forecasts (ECMWF) is another good example as a result of an Action through its evolution to become an independent intergovernmental organisation with its own structure and headquarters supported by 34 states.

The key findings of COST networks not only contribute to the atmospheric drivers on the impacts of the global change but also increase the understanding of the function of marine ecosystems and its response to climate change. A number of Actions in the field of marine science have developed observing system to integrate the dynamic response of sea-level variations to combine effects of various natural drivers into multi-criteria tools by bringing together oceanographers and meteorologists. These developments urged for an integrated implementation of technology in sea-level monitoring, and for further international agreements on data storage and exchange.

A wide range of disciplines, evaluating the complex interactions between the oceans and the global change, geosciences, natural resources management, environmental monitoring, biogeochemical cycles,  ecology, hydrology, natural disasters, water cycle have well undertaken through COST Action networks. The results were published in high impact journals, guidelines were represented in position papers leading to new research projects on a global scale.  Participation in COST leads to significant results and follow-up in terms of number of proposals submitted for collaborative research in Horizon 2020, with a striking success rate of 33% (the Horizon 2020 average is at 12.2%). By enabling researchers and innovators from all career levels to network, COST connects complementary funding schemes, facilitating the entry of promising young talents into these schemes.

COST is committed to reinforcing its role as the leading networking instrument in the European Research Area (ERA), while creating even higher tangible impact on society.

How to cite: Karaca, D.: Creating Impact through COST Action networks, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22484, https://doi.org/10.5194/egusphere-egu2020-22484, 2020.

About 6 million years ago, the Mediterranean basin was the focus of one of the most extraordinary events in the recent geological history of the Earth: the so-called Messinian Salinity Crisis (MSC). MEDSALT aims to create a new flexible scientific network addressing the causes, timing, emplacement mechanisms, and consequences – at local and planetary scale – of the largest and most recent ‘salt giant’ on Earth: the Mediterranean Salt Giant (MSG). The MSG is a 1.5 km thick salt layer that was deposited on the bottom of deep Mediterranean basins about 5.5 million years ago, in late Miocene (Messinian), and is preserved beneath the deep ocean floor today. The origin of the Mediterranean salt giant is linked the Messinian Salinity Crisis. Research on the MSC has initiated one of the longest-living scientific controversies in Earth Science. Pioneering scientific drilling in 1970 induced some researchers to publish the theory of the ‘desiccation’ of the Mediterranean during the Messinian. In their view the Mediterranean Sea level dropped by 1–2 km and the basin was transformed into a huge hot, dry salt lake as a consequence of the tectonically-driven closure of the Atlantic gateway at the present-day Gibraltar strait.

This interpretation was successful not only among the scientific community, but also in public opinion. On one hand, the progress of scientific research provided additional evidence for the desiccation theory. On the other hand, researchers questioned the theory, providing alternative interpretations of the geological data, and theoretical arguments supporting a model of salt deposition from a deep brine, assuming a very limited sea level change. Controversial views also exist on the mechanisms that ended the MSC: was it a catastrophic flood of Atlantic waters from the re-opening of the Atlantic gateway, or a slow mixing with brackish water from the Black Sea area first before the re-establishment of the normal marine connection with the Atlantic Ocean? In order to trigger progress on the understanding of the MSC, a widespread international scientific community has promoted the largest coordinated research on the MSC since its discovery, clustered around scientific drilling. COST (European Cooperation in Science and Technology) was identified as the most appropriate tool, as COST Actions provide tools for networking, training, mobility and dissemination. The network has further promoted one Marie Skłodowska-Curie European Training Network (SALTGIANT) offering 15 PhD fellowships across Europe. New contacts have been activated with a variety of stakeholders, including governmental administrations, non-governmental organizations, the industry and, indirectly, society at large, demonstrating the importance that science and society renew a relationship of trust and confidence. In all, 200 scientists are working together – across disciplines such as geophysics, geology, biology, microbiology, and also social sciences – towards a common scientific goal: uncovering the Mediterranean salt giant.

How to cite: Camerlenghi, A. and Aloisi, V.: Uncovering the Mediterranean Salt Giant (MEDSALT) – Scientific Networking as Incubator of Cross- disciplinary Research in Earth Sciences, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3657, https://doi.org/10.5194/egusphere-egu2020-3657, 2020.

EGU2020-12910 | Displays | GI1.2

EU COST Action ES1404-HarmoSnow

Ali Nadir Arslan

The European Cooperation in Science and Technology (COST) promoted and funded the Action ES1404 called “A European network for a harmonized monitoring of snow for the benefit of climate change scenarios, hydrology, and numerical weather prediction,” or “HarmoSnow” (2014-2018). With 29 European COST countries and the international partners Andorra and Taiwan (https://www.cost.eu/actions/ES1404/) HarmoSnow coordinated efforts towards harmonized snow data processing and handling practices by promoting new observing strategies. The vision was to connect different communities, facilitating data transfer, upgrading and enlarging knowledge through networking and linking them to activities in international agencies and global networks (www.harmosnow.eu).

The main aim of HarmoSnow was to enhance the capability of the research community and operational services to provide and exploit quality-assured and comparable observation data on the variability of the state and extent of snow. The overall objectives were (1) Establish a European-wide science network on snow measurements for their optimum use with interactions across disciplines and expertise, (2) Assess and harmonise practices, standards and retrieval algorithms applied to snow measurements, (3) Develop a rationale and long term strategy for snow measurements and their dissemination, (4) Advance snow data assimilation in NWP and hydrological models, (5) Establish a validation strategy for climate, NWP and hydrological models against snow observations and foster its implementation, (6) Training of a new generation of scientists on snow science and measuring techniques with a broader and more holistic perspective.

We will present outcomes from the HarmoSnow activities and discuss how to move forward.

How to cite: Arslan, A. N.: EU COST Action ES1404-HarmoSnow, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12910, https://doi.org/10.5194/egusphere-egu2020-12910, 2020.

EGU2020-22084 | Displays | GI1.2

Results of the cyberparks cost action tu 1306

Eva Savina Malinverni, Roberto Pierdicca, Carlos Smaniotto Costa, Alfonso Bahillo Martinez, and Ernesto Marcheggiani

The present abstract is aimed at describing the activities and results about Cyberparks COST Action TU 1306. The purpose of the action was to increase the knowledge about the existing relationship between Information and Communication Technologies (ICT) and Public Spaces, supported by strategies to improve their use and attractiveness. In such scenario, the project developed several case studies to develop best practices and digital tools able to collect information directly from the users, in real time. Indeed, sensors where installed in Public Spaces, as well as mobile applications that allowed to provide user’s with contextual information and Location Based Services and, at the same time, to collect the so called User Generated Data. In such way, people experiencing a certain place could enhance their knowledge and administration (or public authorities) could understand how user’s exploit it. Moreover, the project stimulated the use of new technologies like Augmented Reality as an additional service, useful to discover the surrounding and enhance the sense of presence of the users. CyberParks allowed to uncover opportunity and risks related to the use of ICTs via the appreciation, design and usage of public spaces. It exploited the benefits of interweaving a green experience with digital engagement via sharing knowledge, experiences and ideas, and analyzing public spaces.

The methodology developed can be of great interest especially for urban planning purposes; in fact, the pen-and-pencil approach for redesigning and rethinking a place can be partially replaced by a data driven approach, that can be more objective and reliable.

More than 50 scientific papers were published and very fruitful Short Term scientific missions. A great number of data was collected from real scenario, demonstrating the effectiveness of the methods adopted to conduct researches and experiment. Another noteworthy output of the project is the exploitation of a multidisciplinary group. In fact, the amalgamation of researchers coming from different scientific disciplines allowed to enhance the knowledge and strength cooperation between humanistic disciplines and digital sciences.

How to cite: Malinverni, E. S., Pierdicca, R., Smaniotto Costa, C., Bahillo Martinez, A., and Marcheggiani, E.: Results of the cyberparks cost action tu 1306, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22084, https://doi.org/10.5194/egusphere-egu2020-22084, 2020.

Underground4value (COST Action CA18110) is a four years’ project (2019-2023) establishing an expert network from twenty-nine countries, with the objective of promoting balanced and sustainable approaches for the conservation and promotion of underground built heritage (UBH). Every year, four underground sites and their local communities become places for experimenting studies, new policies, and participatory approaches. During the first year (April 2019 - March 2020), the sites of Naples (Italy), La Union (Murcia, Spain), Postojna (Slovenia) and Göreme (Cappadocia, Turkey) have been selected. The originality of the approach is that it is geared towards assisting local communities’ decision-making with cultural, scientific and technical knowledge of the underground built heritage, from many different perspectives: archaeology, geo-technics, history, urban planning, cultural anthropology, economics, architecture, cultural tourism, ecology.

The Living Lab approach is used to organise fieldwork, spending time on each site with a mix of participants (international scientists and local practitioners). The idea is to identify and explore social innovations models for empowering local communities and making them part of the UBH promotion process. Collected information is then the basis for developing new research and training, which remain open and accessible. Knowledge transfer is secured by several dedicated tasks, including a Training School, held in last February in Naples, where the trainees have morning learning sessions and afternoon research activities on specific topics occurred in the living labs’ activities.

How to cite: Pace, G.: COST Action Underground4value: Living Labs for the Underground Built Heritage valorisation , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10408, https://doi.org/10.5194/egusphere-egu2020-10408, 2020.

EGU2020-21733 * | Displays | GI1.2 | Highlight

The COST action CA17133 "Circular city"

Natasa Atanasova and Guenter Langergraber

Resource depletion, climate change and degradation of ecosystems are challenges faced by cities worldwide and will increase if cities do not adapt. In order to tackle those challenges, it is necessary to transform our cities into sustainable systems using a holistic approach. One element in achieving this transition is the implementation of nature-based solutions (NBS). They can provide a range of ecosystem services beneficial for the urban biosphere such as regulation of micro-climates, flood prevention, water treatment, food provision and more. However, most NBS are implemented serving only one single purpose. Adopting the concept of circular economy by combining different types of services and returning resources to the city, would increase the benefits gained for urban areas.

The COST Action CA17133 "Implementing nature-based solutions for creating a resourceful circular city" aims to establish a network testing the hypothesis that a circular flow system that implements NBS for managing nutrients and resources within the urban biosphere will lead to a resilient, sustainable and healthy urban environment.

To tackle this challenge the Action comprises five working groups (WGs):

  • WG1: Built environment
  • WG2: Sustainable urban water utilisation
  • WG3: Resource recovery
  • WG4: Urban Farming
  • WG5: Transformation tools

The network of researches, companies and stakeholders from more than 40 countries spread over whole Europe brings together a large diversity of disciplines and is therefore well equipped taking holistic approach on embedding NBS within circular economy. In the presentation we will present the first results already achieved and the future plans of the Action.

How to cite: Atanasova, N. and Langergraber, G.: The COST action CA17133 "Circular city", EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21733, https://doi.org/10.5194/egusphere-egu2020-21733, 2020.

EGU2020-22165 | Displays | GI1.2

Ambient seismic noise suppression in COST action G2Net

Velimir Ilić, Alessandro Bertolini, Fabio Bonsignorio, Dario Jozinović, Tomasz Bulik, Ivan Štajduhar, Iulian Secrieru, and Soumen Koley

The analysis of low-frequency gravitational waves (GW) data is a crucial mission of GW science and the performance of Earth-based GW detectors is largely influenced by ability of combating the low-frequency ambient seismic noise and other seismic influences. This tasks require multidisciplinary research in the fields of seismic sensing, signal processing, robotics, machine learning and mathematical modeling.

In practice, this kind of research is conducted by large teams of researchers with different expertise, so that project management emerges as an important real life challenge in the projects for acquisition, processing and interpretation of seismic data from GW detector site. A prominent example that successfully deals with this aspect could be observed in the COST Action G2Net (CA17137 - A network for Gravitational Waves, Geophysics and Machine Learning) and its seismic research group, which counts more than 30 members. 

In this talk we will review the structure of the group, present the goals and recent activities of the group, and present new methods for combating the seismic influences at GW detector site that will be developed and applied within this collaboration.

 

This publication is based upon work from CA17137 - A network for Gravitational Waves, Geophysics and Machine Learning, supported by COST (European Cooperation in Science and Technology).

How to cite: Ilić, V., Bertolini, A., Bonsignorio, F., Jozinović, D., Bulik, T., Štajduhar, I., Secrieru, I., and Koley, S.: Ambient seismic noise suppression in COST action G2Net, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22165, https://doi.org/10.5194/egusphere-egu2020-22165, 2020.

EGU2020-19560 | Displays | GI1.2

Soil Moisture Retrievals from Unmanned Aerial Systems (UAS)

ruodan zhuang, Salvatore Manfreda, Yijian Zeng, Zhongbo Su, Nunzio Romano, Eyal Ben Dor, Antonino Maltese, Fulvio Capodici, Antonio Paruta, Paolo Nasta, Nicolas Francos, Giuseppe Ciraolo, Brigitta Szabó, János Mészáros, and George P. Petropoulos

Quantification of the spatial and temporal behavior of soil moisture is vital for understanding water availability in agriculture, ecosystems research, river basin hydrology and water resources management. Unmanned Aerial Systems (UAS) offer a great potential in monitoring this parameter at sub-meter level and at relatively low cost. The standardization of operational procedures for soil moisture monitoring with UAS can be beneficial to understanding and quantify the quality of retrieved soil moisture (e.g., from different platforms and sensors).

In this study, soil moisture retrieved from UAS using different retrieval algorithms was compared to collocated ground measurements. The thermal inertia model builds upon the dependence of the thermal diffusion on soil moisture. The soil thermal inertia is quantified by processing visible and near-infrared (VIS-NIR) and thermal infrared (TIR) images, acquired at two different times of a day. The temperature–vegetation trapezoidal model is also used to map soil moisture over vegetated pixels. This trapezoidal model depicts the soil moisture dependence of the surface energy balance. The comparison of the two algorithms helps define a preliminary standard procedure for retrieving soil moisture with UAS.

As a case study, a typical cropland area with olive orchard, cherry and walnut trees in the region of Monteforte Cilento (Italy, Salerno) is used, where optical and thermal images and in situ data were simultaneously acquired. In the Alento observatory, long-term studies on vadose zone hydrology have been conducting across a range of spatial scales. Our findings provide an important contribution towards improving our knowledge on evaluating the ability of UAS to map soil moisture, in support of sustainable natural resources management and climate change studies.

This research is a part of EU COST-Action “HARMONIOUS: Harmonization of UAS techniques for agricultural and natural ecosystems monitoring”.

Keywords: soil moisture, Unmanned Aerial Systems, thermal inertia, HARMONIOUS

How to cite: zhuang, R., Manfreda, S., Zeng, Y., Su, Z., Romano, N., Ben Dor, E., Maltese, A., Capodici, F., Paruta, A., Nasta, P., Francos, N., Ciraolo, G., Szabó, B., Mészáros, J., and Petropoulos, G. P.: Soil Moisture Retrievals from Unmanned Aerial Systems (UAS), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19560, https://doi.org/10.5194/egusphere-egu2020-19560, 2020.

EGU2020-5122 * | Displays | GI1.2 | Highlight

Accelerating Global Science on Tsunami Hazard and Risk Analysis (AGITHAR)

Joern Behrens, Inigo Aniel-Quiroga, Sebastiano D'Amico, Frederic Dias, Ira Didenkulova, Serge Guillas, Stefano Lorito, Finn Lovholt, Jorge Macias, Shane Murphy, Ocal Necmioglu, Rachid Omira, Simone Roedder, and Mathilde Sorensen

Recent tsunami disasters revealed severe gaps between the anticipated level of hazard and the true extent of the event, with resulting loss of life and property. The severe consequences were underestimated in part due to the lack of rigorous and accepted hazard analysis methods and large uncertainty in forecasting the tsunami source mechanism and strength. Uncertainty and underestimation of the hazard and risk resulted in insufficient preparedness measures. While there is no absolute protection against disasters of the scale of mega tsunamis, a more accurate analysis of the potential risk can help to minimize losses from tsunami.
After the major events in 2004 and 2011 many new initiatives originated novel methods for tsunami hazard and risk analysis. However, rigorous performance assessment and evaluation – with respect to guiding principles in tsunami hazard and risk analysis – has not been conducted. In particular, comprehensive uncertainty assessments and related standards are required in order to implement more robust and reliable hazard analysis strategies and, ultimately, better mitigate tsunami impact. This is the core challenge of the proposed COST Action Accelerating Global science In Tsunami HAzard and Risk analysis (AGITHAR).
In our presentation we will demonstrate first results of the Action, assessing research gaps, open questions, and a very coarse roadmap for future research.

How to cite: Behrens, J., Aniel-Quiroga, I., D'Amico, S., Dias, F., Didenkulova, I., Guillas, S., Lorito, S., Lovholt, F., Macias, J., Murphy, S., Necmioglu, O., Omira, R., Roedder, S., and Sorensen, M.: Accelerating Global Science on Tsunami Hazard and Risk Analysis (AGITHAR), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5122, https://doi.org/10.5194/egusphere-egu2020-5122, 2020.

EGU2020-10625 * | Displays | GI1.2 | Highlight

BOTTOMS-UP: Biodiversity of Temperate Forest Taxa to Orient Management Sustainability by Unifying Perspectives

Murat Sarginci, Péter Ódor, Inken Doerfler, Thomas Nagel, Yoan Paillet, Tommaso Sitzia, Flóra Tinya, Admir Avdagić, and Julie Ballweg and the COST Action CA18207

Forests provide essential economic, social, cultural and environmental services. To be able to maintain the provision of these services, sustainable forest management (SFM) is a vital obligation. The maintenance of biodiversity, ranging from gene to ecosystem levels, is essential for functions and associated services, and it is one of the most important criterion for assessing sustainability in the Pan-European region. 
Currently, the majority of SFM Criteria and Indicators focuses on attributes relative to tree species or to the whole forest. With reference to biodiversity conservation, this means that the collected information cannot fully assess whether forests are being managed sustainably. To understand the drivers of forest biodiversity and drive sustainable management, several taxonomic groups should be investigated, since they may respond differently to the same environmental pressures. However, up to now, broad multi-taxonomic analyses were mainly performed through reviews and meta-analyses which limit our holistic understanding on the effects of forest management on different facets of biodiversity. Recently, several research institutions took up the challenge of multi-taxonomic field sampling. These local efforts, however, have limited extrapolation power to infer trends at the European scale. It is high time to share, standardize and use existing multi-taxon data through a common platform to inform sound management and political decisions. Biodiversity indicators have also some potential to be used in evaluation of impact of forest management on soils and surface waters in terms of naturalness, degradation and reclamation.
We present the COST Action CA18207 “Biodiversity of Temperate forest Taxa Orienting Management Sustainability by Unifying Perspectives” (Bottoms-Up). It will gather the most comprehensive knowledge of European multitaxonomic forest biodiversity through the synergy of research groups that collected data locally in more than 2200 sampling units across approximately 300 sites covering nine different European forest types. For each sampling unit, information will be available on at least three taxonomic groups (vascular plants, fungi, lichens, birds and saproxylic beetles being the most represented) and on live stand structure and deadwood. Multi-taxon biodiversity will be associated with: (i) information on forest management based on observational studies at the coarse scale, and (ii) structural data deriving from forest manipulation experiments at the fine scale. 

Specific objectives are:
• Developing a standardized platform of multi-taxon data;
• Establishing a network of forest sites with baseline information for future monitoring;
• Designing shared protocols for multi-taxon sampling;
• Assessing the relationships between multi-taxon biodiversity, structure and management;
• Creating a coordinated network of forest manipulation experiments;
• Evaluating indicators and thresholds of sustainability directly tested on biodiversity;
• Developing management guidelines defining sustainable management to be applied in forest certification and within protected areas.

The Action involves about 80 researchers and stakeholders from 29 countries and represents an outstanding opportunity to develop a strong network of collaboration for standardized broad-scale multitaxon studies in Europe.

Keywords:  Multi-taxon, Pan-European region, Sustainable Forest Management. 

 

How to cite: Sarginci, M., Ódor, P., Doerfler, I., Nagel, T., Paillet, Y., Sitzia, T., Tinya, F., Avdagić, A., and Ballweg, J. and the COST Action CA18207: BOTTOMS-UP: Biodiversity of Temperate Forest Taxa to Orient Management Sustainability by Unifying Perspectives, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10625, https://doi.org/10.5194/egusphere-egu2020-10625, 2020.

EGU2020-14370 * | Displays | GI1.2 | Highlight

inDust: International Network to encourage the use of monitoring and forecasting DUST products

Sara Basart and Slodoban Nickovic and the inDust Core Group

Sand and Dust Storms (SDS) are extreme meteorological phenomena that generate significant amounts of airborne mineral dust particles. SDS plays a significant role in different aspects of weather, climate and atmospheric chemistry. Also, SDS represents a severe hazard for life, health, property, environment and economy, which is aligned with several Sustainable Developed Goal (SDG) targets established by the United Nations (UN). Understanding, managing, and mitigating SDS risks and effects requires fundamental and cross-disciplinary knowledge.

Over the last few years, there is an increasing need for SDS accurate information and predictions to support early warning systems, and preparedness and mitigation plans in addition to growing interest from diverse stakeholders, such as solar energy plant managers, health professionals, aviation and policymakers from environmental and health public sectors. Current attempts to transfer tailored products to end-users are not coordinated, and the same technological and social obstacles are tackled individually by all different groups, a process that makes the use of data slow and expensive.

The EU-funded COST Action inDust (www.cost-indust.eu, CA16202) has an overall objective to establish a network involving research institutions, service providers and potential end-users of information on airborne dust that can assist the diverse socio-economic sectors affected by the presence of high concentrations of atmospheric dust. In line with this main objective, the network is being worked on the identification and engagement of representatives of dust affected socio-economic sectors (targeting on air quality and health, aviation and solar energy) from different countries in Europe but also in North Africa and the Middle East. Moreover, the participation of South African, American and importantly Asian partners brings the possibility of extending the application of the developed products, protocols and tools well beyond the European borders, including areas like Asian regions where dust particles play a significant role in the air quality and meteorological processes.

The primary outcomes of the network are the identification of the needs of the various and new dust-related products and services able to satisfy these needs. As a result, the network has been working on a dust catalogue which includes an overview of (ground-based and satellite) observations and model products.

How to cite: Basart, S. and Nickovic, S. and the inDust Core Group: inDust: International Network to encourage the use of monitoring and forecasting DUST products, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-14370, https://doi.org/10.5194/egusphere-egu2020-14370, 2020.

EGU2020-20728 | Displays | GI1.2

Profiling the Atmospheric Boundary Layer at European Scale - COST Action

Kreso Pandzic and Tanja Likso

A three-dimensional spatial analysis of atmosphere, including its boundary layer, has become possible after upper air vertical atmospheric observation started. Mountain observatories, as e.g. at the Sonnblick Observatory in Austrian Alpine, which operates since 1866, belong to a group of such observation. During 18-th and 19-th century upper air observations have been made by balloons equipped with meteorological instruments. The first such observation was done at Glasgow in 1749. The first radiosounding vertical profile observation was done in 1927. At the end of 1940-s an operative network of radiosounding stations has been started to use for construction of upper air synoptic maps and three-dimensional spatial atmospheric analyses. The first meteorological satellite was launched in 1960. Weather radar, airplane observation and wind and air temperature profilers take place since then. A description of these developments in Europe are the main subject of this study. Criteria for vertical profile observation, data processing and analysis have  been continuously done by the World Meteorological Organization and their development by states and European Union research projects including COST actions. Details are also represented.

KEY WORDS: vertical profiling of atmosphere, Europe, COST actions

How to cite: Pandzic, K. and Likso, T.: Profiling the Atmospheric Boundary Layer at European Scale - COST Action, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20728, https://doi.org/10.5194/egusphere-egu2020-20728, 2020.

EGU2020-11216 | Displays | GI1.2

X-MINE project (H2020): testing the capabilities of X-ray techniques in drill core scanning and ore sorting

Marian Munteanu, Stefan Sädbom, Janne Paaso, Mikael Bergqvist, Nikolaos Arvanitidis, Ronald Arvidsson, Jacek Kolacz, Evangelos Bakalis, Desislav Ivanov, Kleio Grammi, Juha Kalliopuska, Stepan Polansky, Michael Gielda, Jan-Erik Björklund, Lotta Sartz, Karin Högdahl, Paul Attiwell, Edward Lynch, Stefan Luth, and Edine Bakker

The X-MINE project (Real-Time Mineral X-Ray Analysis for Efficient and Sustainable Mining), under the Horizon 2020 program (grant agreement no. 730270), combines high-energy XRF sensors, multi-energy XRT sensors and optical sensors to be able to support both drill core analysis and mineral sorting applications, including high speed processing of low-grade ores.

The aims of the project are: (1) smart exploration, (2) selective (more efficient) drilling and (3) optimal extraction in existing mine operations. The expected effects of project outputs include: reduced quantity of mining waste by a better selection of the ore; reduced consumption of energy, explosives and other chemicals thus less CO2 and NO2 emissions; further critical raw materials acquisition for the EU; better planning of mining operations; increased resource efficiency.

On the purpose of smart exploration, multi-parameter 3D near-mine ore deposit models were built, under SGU coordination, for 4 mining areas: Lovisagruvan(Sweden), Assarel(Bulgaria), Skouriotissa-Apliki(Cyprus) and Mavres Petres-Piavitsa(Greece).

The project improves and combines various online sensing technologies, integrates the multi-sensor solution in an online analysis platform and demonstrates the solution in real mining operations. Two prototypes are being developed and demonstrated in the X-MINE project.

(1) A sensitive transportable X-ray Analyser based on undertaken drill core scanning (GeoCore X10, delivered by Orexplore and further developed within X-Mine project). This performs penetrative combined and integrated XRF-XRT scanning, providing assaying of exploration drill cores and 3D tomographic imaging, that also allows linear and structural annotations and measures bulk density.

(2) A complex analyser, developed by X-Mine consortium, integrated in a sorting line by Comex. The multisensory analyser unit uses XRT-XRF based scanners and 3D cameras, platforms, algorithms and software developed by Orexplore, VTT, Advacam, and Antmicro.

The X-Mine project has reached the phase of pilot demonstration. The prototypes are being tested on various types of mineralisations and rocks from the four operating mines mentioned above. The tests done so far showed that the drill core scanner allows the tomographic observation and structural study of the cores, which could be ore-genetically evaluated and interpreted. Elemental composition is analysed and bulk density is measured for 1 m of core and calculated for segments as short as 8 mm based on estimated mineralogy. The scanning can be done at a speed of 3-4 meters of NQ-size drill core per hour with results available immediately and therefore useful while the drill rig is still on site.

The development of the new X-MINE sorting application started with laboratory and full-scale tests, and base line studies of previously available dual-energy X-ray technology. A first full-scale initial test at Lovisagruvan indicated that 75% of available size fractions are amenable for sorting, although alternative crushing/size screening may increase sortable fractions. Laboratory and base line studies performed so far, at a speed of 17-20 tons / hour, indicate that waste rock may be reduced by as much as 22 % for some materials.

The testing of the prototypes continues, with special focus on the calibration for different matrix/grade combinations and optimization of hardware, software, algorithms and productivity.

How to cite: Munteanu, M., Sädbom, S., Paaso, J., Bergqvist, M., Arvanitidis, N., Arvidsson, R., Kolacz, J., Bakalis, E., Ivanov, D., Grammi, K., Kalliopuska, J., Polansky, S., Gielda, M., Björklund, J.-E., Sartz, L., Högdahl, K., Attiwell, P., Lynch, E., Luth, S., and Bakker, E.: X-MINE project (H2020): testing the capabilities of X-ray techniques in drill core scanning and ore sorting, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11216, https://doi.org/10.5194/egusphere-egu2020-11216, 2020.

EGU2020-11212 | Displays | GI1.2

BSUIN – Baltic Sea Underground Innovation Network

Jari Joutsenvaara and the BSUIN collaboration

The Baltic Sea region hosts numerous underground facilities or underground laboratories (Uls). The Baltic Sea Underground Innovation Network (BSUIN) there are six such facilities, all unique in their characteristics and operational settings, e.g. located in existing or historical mines, research tunnel networks or as a dedicated underground laboratory for a specific purpose. BSUIN project concentrates on the making the Uls more accessible for current and new users,  helping the Uls to understand their infrastructural challenges and possibilities, and through joint marketing to attract a broader spectrum of users into their facilities.

The underground laboratories participating in BSUIN are Callio Lab (Pyhäjärvi Finland), ÄSPÖ Hard Rock Laboratory (Oskarshamn, Sweden), Ruskela Mining Park (Ruskeala, Russia), Educational and research mine Reiche Zeche (Freiberg, Germany), Underground Low Background Laboratory of the Khlopin Radium Institute (St.Petersburg, Russia) and the Conceptual Lab development co-ordinated by KGHM Cuprum R&D centre (Poland).

We will present the overview of the project, key outcomes, findings and recommendations for underground laboratories in general. The key outcomes of the project for the individual underground laboratories consist of characterisation of the structural, geological and operational environments together with information on the governing legislation and authorities for the underground sites. Underground risks and challenges in the underground working environment have been documented to help the further development of the individual underground laboratories. Service designs were developed together with the ULs to enhance user support and to attract a broader spectrum of users.  To help users with innovation and innovation management the variety of the innovation services was documented to be used as bases for the future operational development of the ULs. To support the marketing, coordinate activities and develop the cooperation an umbrella organisation European Underground Laboratories association (EUL) will be established to carry on the work started in BSUIN.

The Baltic Sea Underground Innovation Network, BSUIN, is funded by the Interreg Baltic Sea Region Programme. 

How to cite: Joutsenvaara, J. and the BSUIN collaboration: BSUIN – Baltic Sea Underground Innovation Network , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11212, https://doi.org/10.5194/egusphere-egu2020-11212, 2020.

EGU2020-19835 | Displays | GI1.2

TU1208 GPR Association: Why? How? What?

Lara Pajewski

TU1208 GPR Association (www.gpradar.eu/tu1208/) is a follow-up initiative of COST Action TU1208 “Civil engineering applications of ground penetrating radar” (www.gpradar.eu), which ended in October 2017. The association inherited the same primary objective of the Action, namely, to exchange and increase scientific-technical knowledge and experience of ground penetrating radar (GPR) technique, whilst promoting a wider and more effective use of this safe and non-destructive inspection method. Currently (2019) the association involves 41 Members from 30 Institutes in 14 Countries; participating institutions include universities, research centers, public agencies, GPR manufacturers and end-users. The association is open to experts from all over the world and not 'only' to Members of COST Action TU1208. The research activities supported by the association cover all areas of GPR technology, methodology, and applications.

Why? 

The motivations to maintain, expand and leverage our COST network after the end of the Action could be summarized by saying that during the Action’s lifetime we acquired awareness that “we are stronger together.” There can be different ways to keep a COST network alive after the Action’s end, the most common being continuation through funding of another Action or EU/international collaborative research projects. We realized that establishing an association would offer a great added value. An association is actually a platform to coordinate, complement, and support any new initiatives undertaken by its members; it helps to avoid fragmentation of research, achieve better harmonization of activities and approaches, and constantly attain involvement of new actors. In perspective, an association can potentiate the contact of a community of innovators with policy makers. Moreover, an association gives identity to the group and encourages the discussion of general principles alongside more strictly scientific topics.

How?

TU1208 GPR association was founded in September 2017, before the Action’s Final Conference. The financial model is a non-profit scientific association with statutes, registered with the Italian Revenue Agency. Administrative and operative offices are in Rome. The simplest financial structure was chosen for the association, which has a fiscal code but does not have a VAT number; thus, the association can receive social quotas, donations, and occasionally other types of incomes. This model is the easiest to run and can be upgraded in the future, if useful.

What?

We believe that the key principles and values that we experienced together in COST Action TU1208 continue to matter notwithstanding the Action ended, so we aim to apply them and spread them out.

The association publishes books, proceedings, and educational material. We have founded the first peer-reviewed scientific journal dedicated to GPR, “Ground Penetrating Radar” (www.gpradar.eu/journal/): this is the most challenging and ambitious initiative that the association has initiated and carried out so far. Our publications are distributed in true open access, free to both Authors and Readers.

We organize networking and educational events, such as workshops, training schools, roundtables and scientific sessions in international conferences (including the EGU session «COST Actions in Geosciences», wherein this abstract is presented, and the EGU session «Ground Penetrating Radar: Technology, Methodology, Applications, and Case Studies»). The association has also funded/co-funded a few scientific missions.

How to cite: Pajewski, L.: TU1208 GPR Association: Why? How? What?, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19835, https://doi.org/10.5194/egusphere-egu2020-19835, 2020.

Scientists and experts participating in COST Actions can benefit from a wide range of COST networking tools. Meetings, workshops, conferences and training schools can be organized. Short-term scientific missions (STSM) can be funded: these are exchange visits where an Action Member spends five days up to six months abroad, in a host institution; the aim of STSMs is to foster collaboration between institutions and sharing of new techniques that may not be available in a participant’s home institution. COST also funds dissemination and communication of Action’s outcomes within research communities and beyond. Finally, conference grants for early-career researchers from Inclusiveness Target Countries (ITC) aim at helping participants from ITC to attend international science and technology related conferences that are not organised by COST Actions.

In this presentation, we discuss the challenges and lessons learnt in COST Action TU1208 “Civil engineering applications of ground penetrating radar” [1] while using COST networking tools to fulfill the objectives of the Action, enhance its impact, and maximize the benefits of its Members. We consider one tool at a time focusing on the obstacles that we encountered and how we overcame them, as well as giving hints on how the Action and its Members made the most from the use of the tool. We describe how the use of the tools changed during the Action’s lifetime. 

COST networking tools can of course be used in a customary way and they are all extremely frutiful. More creative solutions can be implemented too, to keep Members engaged or achieve particular goals. Therefore, this presentation continues with examples of less-common exploitations of the tools in TU1208. For instance, we used the “Meeting” tool for the organization of a series of science communication initiatives aimed at increasing public awareness about ground penetrating radar capabilities and applications and at establishing a dialogue with policymakers, stakeholders and end-users of our research (TU1208 GPR RoadShow [2]); the Roadshow included non-scientific workshops, practical demonstrations, and a series of educational activities with children and citizens. We repeatedly exploited the “Meeting” tool also for one week gatherings with a small number of Members, where we worked full-time together at bringing forward specific Action’s activities, one of the challenges of COST Actions being the lack of funds to finance research and the difficulty to “make Members work” for the Action when they are at their home institutions.

We hope that recently started Actions can build upon our experience.

 

[1] L. Pajewski, A. Benedetto, X. Dérobert, A. Giannopoulos, A. Loizos, G. Manacorda, M. Marciniak, C. Plati, G. Schettini, I. Trinks, "Applications of Ground Penetrating Radar in Civil Engineering – COST Action TU1208," Proc. 7th IWAGPR, 2013, Nantes, France, pp. 1-6, doi.org/10.1109/IWAGPR.2013.6601528

[2] L. Pajewski, H. Tõnisson, K. Orviku, M. Govedarica, A. Ristić, V. Borecky, S. S. Artagan, S. Fontul, and K. Dimitriadis, “TU1208 GPR Roadshow: Educational and promotional activities carried out by Members of COST Action TU1208 to increase public awareness on the potential and capabilities of the GPR technique,” Ground Penetrating Radar, Volume 2(1), March 2019, pp. 67-109, doi.org/10.26376/GPR2019004

How to cite: Ristic, A., Pajewski, L., Govedarica, M., and Vrtunski, M.: Use of COST networking tools to achieve the objectives of a COST Action, enhance its impact, and maximize the benefits of its Members – challenges and lessons learnt in COST Action TU1208, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19699, https://doi.org/10.5194/egusphere-egu2020-19699, 2020.

EGU2020-20324 | Displays | GI1.2

The European Astrobiology Institute – a sustainable structure launched by a COST Action and other European initiatives

Wolf Geppert

EGU2020-13066 * | Displays | GI1.2 | Highlight

BioLink: Linking belowground biodiversity and ecosystem function in European forests

Douglas Godbold, Mark Bakker, Ivanno Brunner, and Martin Lukac

Biodiversity of ecosystems is an important driver for the supply of ecosystem services to people. Soils often have a larger biodiversity per unit surface area than what can be observed aboveground. Here, we present what is to our knowledge, the most extensive literature-based key-word assessment of the existing information about the relationships between belowground biodiversity and ecosystem services in European forests. The belowground diversity of plant roots, fungi, prokaryota, soil fauna, and protists was evaluated in relation to the supply of Provisioning, Regulating, Cultural, and Supporting Services. The soil biota were divided into 14 subgroups and the ecosystem services into 37 separate services. Out of the 518 possible combinations of biotic groups and ecosystem services, no published study was found for 374 combinations (72%). Of the remaining 144 combinations (28%) where relationships were found, the large majority (87%) showed a positive relationship between biodiversity of a belowground biotic group and an associated ecosystem service. We concluded that (1) soil biodiversity is generally positively related to ecosystem services in European forests; (2) the links between soil biodiversity and Cultural or Supporting services are better documented than those relating to Provisioning and Regulating services; (3) there is a huge knowledge gap for most possible combinations of soil biota and ecosystem services regarding how a more biodiverse soil biota is associated with a given ecosystem service. Given the drastically increasing societal demand for knowledge of the role of biodiversity in the functioning of ecosystems and the supply of ecosystem services, we strongly encourage the scientific community to conduct well-designed studies incorporating the belowground diversity and the functions and services associated with this diversity.

How to cite: Godbold, D., Bakker, M., Brunner, I., and Lukac, M.: BioLink: Linking belowground biodiversity and ecosystem function in European forests, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13066, https://doi.org/10.5194/egusphere-egu2020-13066, 2020.

EGU2020-11057 | Displays | GI1.2

Growing the Urban Forest. From our Practitioners’ perspective to Field Initiatives

Maria Beatrice Andreucci and Naomi Zürcher

EGU2020-10977 | Displays | GI1.2

Carbonate System and Acidification of the Adriatic Sea

Valentina Turk, Nina Bednarsek, Jadran Faganeli, Blaženka Gasparovic, Michele Giani, Roberta Guerra, Nives Kovac, Alenka Malej, Bor Krajnc, Donata Melaku Canu, and Nives Ogrinc

Although the marginal seas represent only 7% of the total ocean area, the CO2 fluxes are intensive and important for the carbon budget, exposing to an intense process of anthropogenic ocean acidification (OA). A decline in pH, especially in the estuarine waters, results also from the eutrophication-induced acidification. The Adriatic Sea is currently a CO2 sink with an annual flux of approximately -1.2 to -3 mol C m-2 yr-1 which is twice as low compared to the net sink rates in the NW Mediterranean (-4 to -5 mol C m-2 yr-1). Based on the comparison of two winter cruises carried out in in the 25-year interval between 1983 and 2008, acidification rate of 0.003 pHT units yr−1 was estimated in the northern Adriatic which is similar to the Mediterranean open waters (with recent estimations of −0.0028 ± 0.0003 units pHT yr−1) and the surface coastal waters (-0.003 ± 0.001 and -0.0044 ± 0.00006 pHT units yr−1). The computed Revelle factor for the Adriatic Sea, with the value of about 10, indicates that the buffer capacity is rather high and that the waters should not be particularly exposed to acidification. Total alkalinity (TA) in the Adriatic (2.6-2.7 mM) is in the upper range of TA measured in the Mediterranean Sea because riverine inputs transport carbonates dissolved from the Alpine dolomites and karstic watersheds. The Adriatic Sea is the second sub-basin (319 Gmol yr-1), following the Aegean Sea (which receives the TA contribution from the Black Sea), that contribute to the riverine TA discharges into the Mediterranean Sea. About 60% of the TA inflow into the Adriatic Sea is attributed to the Po river discharge with TA of ~3 mM and TA decreases with increasing salinity. Saturation state indicates that the waters of the Adriatic are supersaturated with respect to calcite (ΩCa) and aragonite (ΩAr) throughout the year. However, saturation states are considerably lower in the bottom water layers, due to the prevalence of benthic remineralization processes in the stratification period. The seasonal changes of the chemical and environmental conditions and relatively small size of the Adriatic Sea area the microbial community composition, function (growth, enzymatic activity) and carbon and nitrogen biogeochemical cycles. Significant effects on calcifying organisms and phytoplankton are expected while the effects of possible OA on microbially-driven processes are not known yet.

How to cite: Turk, V., Bednarsek, N., Faganeli, J., Gasparovic, B., Giani, M., Guerra, R., Kovac, N., Malej, A., Krajnc, B., Melaku Canu, D., and Ogrinc, N.: Carbonate System and Acidification of the Adriatic Sea, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10977, https://doi.org/10.5194/egusphere-egu2020-10977, 2020.

EGU2020-1282 * | Displays | GI1.2 | Highlight

COST Action LAND4FLOOD - Natural Flood Retention on Private Land: Overview of recent activities and future plans

Nejc Bezak, Lenka Slavíková, and Thomas Hartmann

Every devastating large flood usually leads to initiation of different flood risk reduction activities. There are numerous options available how to approach flood risk management. Only limited part of approaches considered land management as significant topic in the flood risk management. Therefore, efficient and effective land management for flood retention and resilience is needed. COST action LAND4FLOOD (CA 16209) deals with natural flood retention on private land. More information about the specific cost action can be found on the web-page http://www.land4flood.eu/ and LAND4FLOOD twitter account @Land4Flood.

Some of the recent activates of the COST action include:

-Organization of series of workshops on different topics such as “Strategies for achieving flood resilience”, “Delivering Nature-Based Solutions (NBS)”, “NBS for flood retention in Southern Europe”, “Compensation Mechanism for Flood Storage”, “Innovative and successfully implemented strategies for achieving resilience in Flood Risk Management with a special focus on private and public property flood resilience” and organization of stakeholders meetings.

-Publication of policy briefs entitled “How Private Land Matters in Flood Risk Management?” that is also translated in French and Spanish and “Compensation for Flood Storage” that is available in Portuguese, Spanish, Czech and French versions.

-Support of multiple Short Term Scientific Missions (STSM) and ITC and conference grants.

-Publication of book about “Nature-based Flood Risk Management on Private Land” and multiple scientific papers.

-Preparation of the LAND4FLOOD leaflet (i.e. http://www.land4flood.eu/wp-content/uploads/2019/10/Leaflet-LAND4FLOOD-final.pdf) that is translated into Albanian, Bulgarian, Slovakian and Slovenian languages.

Moreover, the COST action will finish in September 2021, thus there are still several ongoing projects such as open STSM calls, workshop initiations, research project application and book proposals. For example, a recent book proposal that has just been launched will review what we know about flooding land and how to implement spatial flood risk management and resilience. More specifically, as pointed out land is needed for flood risk management. Thus, to store excess water and retain it without major damage. However, this land is often in private ownership. This book proposal will explore different options regarding storage of water in the catchment during flood events: in the hinterland with decentral measures, along the rivers in polders, washlands and in resilient cities. The book will put the focus on land as a biophysical system (including hydrological aspects), as a socio-economic resource, and as a possible solution for flood risk reduction (i.e. asking for policy interventions to activate the land for flood protection measures). These three areas (i.e. hinterland, along the streams, in resilient cities) and the three analytical lenses (i.e. processes to influence stakeholders and interests in land, socio-economic context of land and environmental conditions of land for retention) will indicate how to use land to reduce the impact of flooding.

How to cite: Bezak, N., Slavíková, L., and Hartmann, T.: COST Action LAND4FLOOD - Natural Flood Retention on Private Land: Overview of recent activities and future plans, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1282, https://doi.org/10.5194/egusphere-egu2020-1282, 2020.

EGU2020-22143 | Displays | GI1.2

Perspectives for Planning Approaches in Promoting Underground Built Heritage - COST Action Underground4value

Carlos Smaniotto Costa, Tatiana Ruchinskaya, and Konstantinos Lalenis

The COST Action 18110 Underground4value (http://underground4value.eu) aims to advance knowledge on how to guarantee continuity of use and significance of underground historic fabric. It is collecting information, experiences and knowhow to base the development of research and training. The Action focusses on underground regeneration, revitalisation of the public realm and skills development for people concerned with underground heritage.

This contribution centres the attention of the Working Group on Planning Approaches. It also looks at the role of local authorities, as enablers and facilitators, in coordination, use  and management of underground built heritage. In this framework underground built heritage is considered as a social resource with integrated programmes of physical, economic and social measures, backed by strategic stakeholder dialogue.

On the one hand, this contribution discusses the structure and goals of the WG, as it pays attention to the necessary complementarities between functional approaches – at the level of regions and city – and social and cultural approaches involving citizens’ engagement and empowerment – at the local level. This WG aims to provide a reflection on sustainable approaches to preserve the underground built heritage and, at the same time, to unfold the case by case approach for potential use of underground space. On the other hand, to achieve its objectives the WG on Planning Approaches is setting together potentials and constraints in the efforts to make better use of underground heritage. This contribution, therefore, sheds lights on the preliminary results of the WG. It is centred on the learned lessons, challenges and barriers - from a planning science perspective - that experts met in their efforts to tackle Underground Built Heritage. Achieving this goal makes the call for an educational paradigm shift - as the Action is not only interested in compiling the results, rather on experiences that can be analysed and learned. This requires a dynamic understanding of knowledge, abilities and skills, towards creating more effective coalitions of ‘actors’ within localities, by developing structures, which encourage long term collaborative relationships. Enabled by the gained knowledge, the WG will define the best tailored ways to forward this knowledge for planners and decision-makers.

How to cite: Smaniotto Costa, C., Ruchinskaya, T., and Lalenis, K.: Perspectives for Planning Approaches in Promoting Underground Built Heritage - COST Action Underground4value, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22143, https://doi.org/10.5194/egusphere-egu2020-22143, 2020.

EGU2020-20601 | Displays | GI1.2

A European Network for Extreme Atmospheric Events Detection and Monitoring

Riccardo Biondi and Stefano Corradini

Deep convective systems and explosive volcanic eruptions are destructive events causing deaths, injuries, damage to infrastructure. They account for the major economic damages in several countries, present several serious hazards to society, including impact to aviation safety and potential longer-term deleterious effects on weather and climate. The number and the intensity of severe convective events have increased in the last decades in some areas of the globe including Europe and it is going to further increase in a climate change environment. Relatively small eruptions could affect the economy of an entire continent as demonstrated in 2010 by the Eyjafjallajokull eruption. Due to the multi- and trans-disciplinary effects at local, regional and global scales, convective and volcanic clouds include impacts to several economic sectors such as telecommunications, transportation, health, insurances, agriculture, solar energy etc., raising the interest of diverse stakeholders and policymakers. However, the coordination between the different communities is still very difficult. On the one hand, measurement products lack harmonised quality indicators, data formats and measurement schedules. On the contrary, current attempts to transfer tailored products to end-users are not coordinated, and the same technological and social obstacles are tackled individually by different groups, a process that makes the use of data slow and expensive. The flow of information and knowledge between measurement, models, and society requires translation across disciplinary and cultural boundaries. The result is that current data-model-user cooperation becomes increasingly fractured and a potentially immense benefit for Europe’s end users remains unexplored. 

The overall objective of this action is to establish a network involving different communities interested on extreme atmospheric events, such as pilots, aircraft engines manufacturers, air traffic managers, modellers, aircraft companies, atmospheric physicists, meteorologists, policymakers and stakeholders. The network should coordinate the research activity for creating user-oriented operational and tailored products, understanding the needs of final users, to define a standard product format easily understandable by all the players, better coordinate the early warning activities, and establishing a new fast and efficient information transfer process within all the parties at international level. From scientific point of view, there is an urgent need to share ideas among scientists in nearby fields, to educate and train future researchers in the techniques and instruments for monitoring, detecting and modeling “extreme clouds”, to develop new techniques and to integrate data coming from different systems. Extreme atmospheric events do not have any border, thus the involvement of as many countries as possible would be beneficial for the action. The monitoring network of such kind of phenomena is not adequate in several countries due to different reasons such as unpopulated areas, political instability, and poverty. Conversely, availability of observational data from source regions is fundamental for monitoring and forecasting. Thus, the involvement and collaboration with near neighbour countries is very important. We have already established a good network with the aim of creating a future COST Action on this topic, with 23 countries and 35 different institutes involved but we are still missing collaborations from several eastern and southern European countries.

How to cite: Biondi, R. and Corradini, S.: A European Network for Extreme Atmospheric Events Detection and Monitoring, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20601, https://doi.org/10.5194/egusphere-egu2020-20601, 2020.

EGU2020-13645 | Displays | GI1.2

Ground penetrating radar investigations in Quebrada Montes, Lobitos, Peru

Lai Bun Lok, Diego Almendrades, Michael Alderson, Alejandro Pizarro, Andres Bustamante, and John Shi

The dry equatorial forests in the north-western coast of Peru suffer from acute water stress and man-driven deforestation. Recent estimates indicate that the forests have reduced to approximately 10% of their original size. There are local reforestation efforts currently underway, for example to prevent the extinction of native species such as the Peruvian Plantcutter songbird (Phytotoma raimondii). However, irrigation needed to support such efforts is severely challenged by the issues of water scarcity in the region. These adverse effects are also being experienced at a local level by the nearby rural community in Lobitos.

The groundwater resources in Lobitos could potentially offer a solution to the above issues for the local community. However, a scientifically informed and sustainable method of mapping and utilising this resource is needed. To provide supporting evidence in this effort, an extensive ground penetrating radar survey was conducted using a commercial 80 MHz impulse radar to characterise the near subsurface within a 90 hectare plot called Ecológica Tallán, which is part of a natural dry water channel in Quebrada Montes and declared as an important conservation area for the district.

Through a pilot study between Lancaster University, EcoSwell Peru and University of Glasgow, we report on initial results from our ground penetrating radar survey to provide a better understanding of the subsurface characteristics in Quebrada Montes, Lobitos.

 

How to cite: Lok, L. B., Almendrades, D., Alderson, M., Pizarro, A., Bustamante, A., and Shi, J.: Ground penetrating radar investigations in Quebrada Montes, Lobitos, Peru, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-13645, https://doi.org/10.5194/egusphere-egu2020-13645, 2020.

EGU2020-7248 | Displays | GI1.2

The Norwegian node for the European Multidisciplinary Seafloor and water column Observatory

Thibaut Barreyre, Ilker Fer, and Bénédicte Ferré

NorEMSO is a coordinated, large-scale deep-ocean observation facility to establish the Norwegian node for the European Multidisciplinary Seafloor and water column Observatory (EMSO). The project aims to explore the under-sampled Nordic Seas to gain a better understanding of the critical role that they play in our climate system and global ocean circulation. An overarching scientific objective is to better understand the drivers for the temporal and spatial changes of water mass transformations, ocean circulation, acidification and thermo-chemical exchanges at the seafloor in the Nordic Seas, and to contribute to improvement of models and forecasting by producing and making available high quality, near real time data. NorEMSO will achieve this by combining expansion of existing and establishment of new observatory network infrastructure, as well as its coordination and integration into EMSO.

NorEMSO comprises of three main components: moored observatories, gliders, and seafloor and water column observatory at the Mohn Ridge (EMSO-Mohn).

Moored observation systems include an array of four moored observatories located at key positions in the Nordic Seas (Svinøy, Station M, South Cape, and central Fram Strait).

Gliders will be operated along five transects across both the Norwegian and the Greenland Seas to monitor circulation and water mass properties at those key locations. Transects in the Norwegian and Lofoten basins will focus on monitoring the Norwegian Atlantic Current, and a transect in Fram Strait will monitor properties and variability in the return Atlantic Water along the Polar Front in the northern Nordic Seas. In addition, transects in the Greenland and Iceland Seas will address the water mass transformation processes through wintertime open ocean convection, and the southbound transport of surface water from the Arctic Ocean and dense water that feeds the lower limb of the Atlantic Meridional Overturning Circulation in the East Greenland Current.

EMSO-Mohn will establish, at the newly discovered hydrothermal site on the Mohn Ridge, a fixed-point seabed-water-column-coupled and wireless observatory with a multidisciplinary approach – from geophysics and physical oceanography to ecology and microbiology. It is primarily directed at understanding hydrothermal fluxes and associated hydrothermal plume dynamics in the water column and how it disperses in an oceanographic front over the Mohn Ridge.

Following EMSO philosophy, NorEMSO will provide data and platforms to a large and diverse group of users, from scientists and industries to institutions and policy makers. The observations will serve climate research, ocean circulation understanding, numerical operational models, design of environmental policies, and education.

How to cite: Barreyre, T., Fer, I., and Ferré, B.: The Norwegian node for the European Multidisciplinary Seafloor and water column Observatory, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7248, https://doi.org/10.5194/egusphere-egu2020-7248, 2020.

EGU2020-3052 | Displays | GI1.2

LIDI 2 – New Evaluation Strategy for Accurate and Precise Clumped Isotope CO2 Analysis on Carbonate Samples

Magda Mandic, Mario Tuthorn, Nils Stoebener, Jens Radke, and Johannes Schwieters

Long Integration Dual Inlet (LIDI) is an established technology which enabled improved accuracy and precision of Δ47 analysis from carbonate samples by utilizing sequential measurement of the full sample and reference, rather than alternating between sample and reference on shorter time periods, as it is done in the classical Dual Inlet method. As of today, there are two key challenges that were limiting further improvements to Δ47 determination: the IRMS must be in a stable temperature environment during long measurement of sample and reference gas, and the crimping of the sample and reference capillaries must be precisely matched, otherwise the produced data will be inaccurate and have reduced precision.

Here we present the improvements made on the sample gas measurement and data evaluation, which we define as LIDI 2.

By applying the LIDI 2 method, sample bracketing is possible following a four-step approach, resulting in fully corrected temperature drift (i.e. eliminated from the data), decreasing the standard deviation by factor of 2. This is a substantial improvement for acquiring clumped isotope data as reaching a very stable temperature of ±0.1°C/h is a challenge for most laboratories.

Alongside eliminating variation in the Δ47 data caused by unstable laboratory air temperature, LIDI 2 also improves the overlap of sample and reference gas signals due to non-perfect crimping of the capillaries. The crimping procedure is laborious and rarely delivers perfect results. Additionally, the pressure adjustment before reference measurement must ensure there is no significant offset between sample and reference intensities. LIDI 2 delivers perfect sample versus reference intensity matching, which results in significantly higher precision on each sample gas analyzed. Standard error of a single sample measurement is improved by up to factor of 2.

The LIDI 2 method delivers improved accuracy and precision on Δ47 measurement from small Carbonate samples, which in combination with the latest advancements in inert capillaries coating and automated contaminant trapping contributes to enhanced clumped isotopes data quality.

 

How to cite: Mandic, M., Tuthorn, M., Stoebener, N., Radke, J., and Schwieters, J.: LIDI 2 – New Evaluation Strategy for Accurate and Precise Clumped Isotope CO2 Analysis on Carbonate Samples, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3052, https://doi.org/10.5194/egusphere-egu2020-3052, 2020.

Geodesists have a different mindset; major or minor involvement in mapping, navigation, positioning, surveying, gravity, coordinate frames and systems, geographical information systems, photogrammetry, 3D laser scanning, satellite orbit determination, orbital mechanics, interferometry and many other fields all help in the grand builtup of a resilient scientist who can emerge with an explorer attitude towards various facets of life; archaeology being one of them, needless to say. If this hybrid composite of mindset and attitude is combined with disciplined and smart usage of geophysical 3D imaging instrumentations deployed frequently by treasure hunters, geodesists might be in a very unique position to make a big bang in the world; finding archaeological Black Swans that might serve to rewrite certain narratives of ancient history is something geodesists must consider deeply. In this presentation, an approach and a discovery will be presented.

How to cite: Hawarey, M.: A Geodesist's Involvement Into Archaeology; A Beginning of Huge Discoveries, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17, https://doi.org/10.5194/egusphere-egu2020-17, 2020.

GI1.3 – The use of historical images and high resolution topography in geosciences

Today, photos play an important role in geoscience and public discussion. When photographical techniques developed during the second half of the 19th century, it took several decades uuntil high mountain areas and specific features could be captured with this technique, as a follow upt o traditional paintings and drawings. In European geography, Friedrich Simony developed the idea of tackling geomorphological processes by time lapse photography. Contemporary literature shows that his technique of combining photography with empirical data and theories was convincing, and that he established a new style of scientific discussion. Still, the comparison of historical with contemporary photography offers scientific insights and information which is not covered by any other type of empirical evidence as measurements, maps or descriptions. For example not only extent, but also firn and debris cover of glaciers, information on type and extent of vegetation,  the width and style of roads, details of infrastructure and cultural practices can be tackled from early photographs.  Several archives do allow not only acess to photographic documents, but also to metadata. Interdisciplinary effort has to be taken to further analyse this wealth of information.

How to cite: Fischer, A.: The role of repeat photography in establishing theories of transition in high mountain environments, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7070, https://doi.org/10.5194/egusphere-egu2020-7070, 2020.

EGU2020-19910 | Displays | GI1.3

Unearthing the forgotten record of glacier change in southeast Greenland

Michael Cooper, Paulina Lewinska, Julian Dowdeswell, Edwin Hancock, William Smith, and David Rippin

Prior to the satellite era (pre-1970s) knowledge of long-term glacier change is sparse. Although some glacier-wide mass balance datasets are available, few records extend beyond twenty years in length, or indeed, start prior to the 1980s; as such, identifying long-term trends between glacier change and global temperatures is difficult. As a result, extending the record of glacier change will not only help to identify such trends, but may also facilitate more robust understanding of future glacier response under a perturbed and varying climate.

Since the ‘heroic age of Arctic (and Antarctic) exploration’, many photographs of polar environments have been captured and stored for historic interest. These photographs, depicting images of past glaciers and ice sheet margins, have, as of yet, untapped potential to provide important insights into past glacier extent, and long-term behaviour.

Using computer-vision methodologies, we present a unique record of georeferenced 3-D elevation models using declassified aerial imagery dating from the 1930s—1980s at quasi-regular time steps. This study focusses upon two sections (ca. 190 km total length) of the southeast margin of the Greenland Ice Sheet (in the vicinity of Kangerlussuaq Glacier), capturing the history of both land- and marine-terminating outlet glaciers, and local glaciers. We examine quantitative information extracted from these reconstructions, allowing us to ‘back extend’ the record of glacial change in this region, by measuring changes in glacial extent, surface profiles and height (elevation), and calculating volume estimates.

How to cite: Cooper, M., Lewinska, P., Dowdeswell, J., Hancock, E., Smith, W., and Rippin, D.: Unearthing the forgotten record of glacier change in southeast Greenland, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19910, https://doi.org/10.5194/egusphere-egu2020-19910, 2020.

EGU2020-9153 * | Displays | GI1.3 | Highlight

Multidecadal elevation changes from spy satellite images: application to glaciers and landslides

Amaury Dehecq, Alex Gardner, Oleg Alexandrov, David Shean, and Pascal Lacroix

Earth’s surface has evolved dramatically over the last 50 years as a consequence of anthropogenic activities and climate change. The observation of such changes at decadal scales is often limited to sparse in-situ observations. The growth of satellite remote-sensing has enabled such monitoring at regional/global scales but generally over less than two decades.

More than 2 million images have been acquired by American reconnaissance (“spy”) satellites on photographic film from the 1960s to the 1980s, and progressively declassified. With near-global coverage and meter to sub-meter resolution, these images have a large potential for many geoscience applications. However the photographic archive represents a unique set of challenges: pre-processing of the scans, correction of the image distortion caused during storing and scanning, poorly known camera positions and parameters. The vast majority of studies using these data rely on tedious manual processing of the data, hindering regional scale applications.

Here, we present the existing datasets and the development of an automated processing pipeline. We will focus in particular on images acquired by the Hexagon mapping camera (1973-1980, 12 missions) at 6-9 m ground resolution. A fully automated workflow has been developed to detect the 1081 fiducial markers present on the image, correct for distortion and stitch the different parts of the image, scanned in multiple sections. The pre-processed images are then used to generate Digital Elevation Models (DEMs) at 24 m resolution with the open-source NASA Ames Stereo Pipeline. The developed workflow is able to automatically solve for the unknown camera positions/orientations and optimally aligns the DEMs to an ancillary DEM for the determination of elevation changes. The application to ~600 images has revealed systematic biases in the retrieved elevation, up to 30 m error, linked to uncertainties in the camera parameters (focal length, lens distortion). We present a methodology to refine these parameters using an ancillary DEM only, without use of manual Ground Control Points. The KH-9 elevation is then validated against existing maps in Europe and Alaska and shows a vertical accuracy of ~5 m (68% interval) to 10-15 m (95% interval), sufficient for the study of large surface deformation (glaciers, landslides).

Finally, we conclude with several use of these data for the estimation of 40 years geodetic glacier mass balance in Europe and Alaska, and irrigation-triggered landslides in South Peru.

How to cite: Dehecq, A., Gardner, A., Alexandrov, O., Shean, D., and Lacroix, P.: Multidecadal elevation changes from spy satellite images: application to glaciers and landslides, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9153, https://doi.org/10.5194/egusphere-egu2020-9153, 2020.

Most large-format analogue aerial photography, especially in the form of roll negatives, is now held in centralised archives, but much still exists elsewhere, notably in the form of positive prints. Whilst many large archiving bodies have been and continue to digitise their holdings of such aerial photography using professional photogrammetric scanners, they are often prohibitive (on the grounds of cost and/or logistics) for use with low-volume, dispersed collections. Therefore, alternative methods are sought, which are presented here. Such alternatives can be subject to relatively poor geometric accuracy, making photogrammetric processing problematic. Here the results of photogrammetric processing with prints digitised using alternative methods are compared and contrasted with digitised roll negatives of the same frames. The quality of resulting elevation data are assessed against reference elevations, using a test site with topography which has remained stable over decades.

How to cite: Ford, A. and Papworth, H.: Digitising archive large-format analogue aerial photography with alternative methods; Implications for photogrammetric processing, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20294, https://doi.org/10.5194/egusphere-egu2020-20294, 2020.

EGU2020-6255 | Displays | GI1.3

Orthomosaics of Historical Aerial Photographs and Horizontal Accuracy Analysis

Ji Won Suh and William Ouimet

Orthomosaics from aerial photographs play a pivotal role in understanding land-use/land cover in broad area and the advent of image processing technology allows us to produce orthoimagery. However, recent advanced technologies are seldom applied to produce historical orthophotos from early or mid 20C old aerial photos in broad extent since they have limited information (e.g. camera position, flying altitude, and yaw) which is critical information for orthomosaics. In this context, this study aims to orthomosaic and georectify historical aerial photographs and validate the horizontal accuracy of orthomosacicked outputs. In order to achieve this, firstly, we collected 117 aerial photographs of 1934 (scale 1:12,000) and 68 of 1951 (scale 1:20,000) from UConn air photo achieve focused on Woodstock town in Connecticut, USA. Secondly, we created GCPs (Ground Control Points) as referenced points where they have not changed over time by overlaying multiple datasets such as LiDAR DEM, hillshade map, recent orthoimagery. Thirdly, we align photos with Control Points (CPs), build a mesh, and build orthomosaics of 1934 and 1951, respectively, using Agisoft Photoscan 1.5. Lastly, calculating RMSE (Root Mean Square Error) and offsets comparing between set of GCPs and CPs from Lidar DEM and set of them digitized from orthomosaics. As a result, RMSE values of GCPs and CPs between 1934 and 1951 mostly show that output of this work is acceptable to use for standard mapping and GIS work or visualization based on ASPRS 1990 horizonal accuracy standard. In addition, we found several factors affect horizontal accuracy of orthomosaics; resolution of aerial photos, spatial distribution of GCPs and CPs, the number of CPs and GCPs, the percentage of lateral overlapping area along flight strips, and margin area. Overall, applying automated orthomosaicking image processing to historical aerial photographs has the potential to represent historical landscape and even detect its change in broad extent.

How to cite: Suh, J. W. and Ouimet, W.: Orthomosaics of Historical Aerial Photographs and Horizontal Accuracy Analysis, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6255, https://doi.org/10.5194/egusphere-egu2020-6255, 2020.

Countrywide surface models from historical panchromatic and true color stereo imagery – a retrospective analysis of forest structures in Switzerland

Mauro Marty1, Lars T. Waser1, Christian Ginzler1

1 Swiss Federal Institute for Forest, Snow and Landscape Research WSL,
Zürcherstrasse 111, CH - 8903 Birmensdorf, Switzerland

Remote sensing methods allow the acquisition of 3D structures of forests over large areas. Active systems, such as Airborne Laser Scanning (ALS) and Synthetic Aperture Radar (SAR) and passive systems, such as multispectral sensors, have been established to acquire 3D and 2.5D data of the earth's surface. Nationwide calculations of surface models with photogrammetric methods from digital stereo aerial images or ALS data are already in operation in some countries (e.g. Switzerland, Austria, some German states).

The availability of historical stereo aerial images allows the calculation of digital surface models from the past using photogrammetric methods. We present a workflow with which we have calculated nationwide surface models for Switzerland for the 1980s, 1990s and 2000s. Current surface models are available from the National Forest Inventory (LFI) Switzerland.

In the context of the Swiss land use and land cover statistics, the Federal Office of Topography (swisstopo) scanned and oriented the analogue black and white stereo aerial photographs with a mean scale of ~1:30'000 of the nationwide flights of 1979 - 84 and1993 - 1997 with 14 µm. The true colour image data from 1998 – 2007 were scanned for the production of the orthoimages swissimage by swisstopo. All these data – the scanned images and the orientation parameters - are also available to the National Forest Inventory (NFI). Within the framework of the NFI, we developed a highly automated workflow to generate digital surface models (DSMs) from many thousands of overlapping frame images covering the whole country. In total, more than 25'000 individual stereo models were processed to nationwide surface models. For their normalization, the digital terrain model of Switzerland 'swissAlti3D' was used. As the image orientation in some areas showed high vertical inaccuracies, corrections had to be made. Data from the Swiss land use and land cover statistics were used for this purpose. At places with constant surface cover since the 1980s (e.g. grassland), correction grids were calculated using the digital terrain model and applied to the surface models.

The results are new data sets on the 2.5D surface of Switzerland from the 1980s, 1990s and 2000s with a high spatial resolution of 1 m. It can be stated that the completeness of the image correlation in forested areas was quite satisfactory. In open areas with agricultural land, however, the matching points were often reduced to the road network, as the meadows and fields in the scanned SW stereo aerial images had very little texture.

This new historical, nationwide data on the horizontal and vertical structure in forests now allows their analysis of changes over the last 40 years.

How to cite: Ginzler, C., Marty, M., and Waser, L. T.: Countrywide surface models from historical panchromatic and true color stereo imagery – a retrospective analysis of forest structures in Switzerland, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12741, https://doi.org/10.5194/egusphere-egu2020-12741, 2020.

EGU2020-22327 | Displays | GI1.3

Development of a 3D Viewer for georeferencing and monoplotting of historical terrestrial images.

Sebastian Flöry, Camillo Ressl, Gerhard Puercher, Norbert Pfeifer, Markus Hollaus, Andreas Bayr, and Wilfried Karel

Mountain regions are disproportionately affected by global warming and changing precipitation conditions. Especially the strong variations within high mountain ranges at the local scale require additional sources in order to quantify changes within this challenging environment. With the emergence of alpine tourism, terrestrial photographs became available by the end of 1800, predating aerial imagery for the selected study areas by 50 years. Due to the earlier availability and oblique acquisition geometry these images are a promising source for quantifying changes within mountainous regions at the local scale. Within the research project SEHAG, methods to process these images and to analyse their potential to quantify and describe environmental changes are developed and applied to study areas in Austria and Italy.

One of the prerequisites for the estimation of changes based on terrestrial imagery is the calculation of the corresponding object point for each pixel in a global coordinate system resulting in a georeferenced orthorectified image. This can be achieved by intersecting the ray defined by the projection center of the camera and each pixel with a digital terrain model, a process known as monoplotting.

So far 1000 terrestrial images with unknown interior and exterior orientation have been collected from various archives for the selected study areas Kaunertal, Horlachtal (both Tyrol, Austria) and Martelltal (South Tyrol, Italy). In order to estimate all camera parameters a 3D viewer for the selection of ground control points has been developed and implemented. The estimation of the exterior and interior orientation is done in OrientAL. 

Preliminary results for selected images show, that especially the developed 3D viewer is an important improvement for the selection of well distributed ground control points and the accurate estimation of the exterior and interior orientation. Monoplotting depends on a digital terrain model, which cannot be computed from the terrestrial images alone due to missing overlap and different acquisitions times. Hence, the combination with historical digital terrain models derived from aerial imagery is necessary to minimize errors introduced due to changes in topography until today. While the large amount of terrestrial images with their oblique acquisition geometries can be exploited to fill occluded areas by combining the results from multiple images, the partly missing or inaccurate temporal information poses another limitation.

With this large image collection, for the first time, we are able to evaluate the use of historical oblique terrestrial photographs for change detection in a systematic manner. This will promote knowledge about challenges, limitations and the achievable accuracy of monoplotting within mountainous regions. The work is part of the SEHAG project (project number I 4062) funded by the Austrian Science Fund (FWF).

How to cite: Flöry, S., Ressl, C., Puercher, G., Pfeifer, N., Hollaus, M., Bayr, A., and Karel, W.: Development of a 3D Viewer for georeferencing and monoplotting of historical terrestrial images. , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22327, https://doi.org/10.5194/egusphere-egu2020-22327, 2020.

EGU2020-595 | Displays | GI1.3

Observing the cryosphere with millimetre wave radar: The case study of Rhône Glacier

William D. Harcourt, David G. Macfarlane, Duncan A. Robertson, Brice Rea, and Matteo Spagnolo

Improving our understanding of the processes governing mass loss from the cryosphere is inhibited by a lack of data at high spatial and temporal resolution. Satellite sensors can provide regional to global scale coverage of glacier processes but fail to resolve processes that occur rapidly, for example glacier calving. To observe these processes, the glaciology community must invest in new techniques that can monitor these processes adequately and fill this major research gap. Here, we will discuss the implementation of an exciting new radar system that is capable of imaging glacial terrain at a high angular resolution and during most weather conditions. The system, named AVTIS2, operates at 94 GHz (~3 mm) and offers a compromise between imaging resolution and penetration through atmospheric obscurants. AVTIS2 scans mechanically across a scene of interest in defined increments of azimuth and elevation angles and generates a 3D data cube of backscattered power. We use a point to maximum power criterion to generate point clouds and construct Digital Elevation Models (DEMs) of the terrain. Because AVTIS2 is a real aperture radar it does not require the phase stability of interferometric radars and can acquire DEMs irrespective of local environmental conditions. In this work, we have used the AVTIS2 radar to map Rhône Glacier in the Swiss Alps, representing the first ever time a millimetre wave radar has been used in this way. To improve our understanding of the performance of AVTIS2 for mapping glaciers, we have characterised the scattering properties of glacial ice at 94 GHz by calculating its Radar Cross Section (RCS). This is key to understanding the performance of AVTIS2 for mapping glaciers. This study represents the first investigation into the reflectivity of ice at millimetre wavelengths and the utility of millimetre wave radar as a surveying tool. We will report on the future application of this instrument in glaciological studies and the unique perspective it can offer.

How to cite: Harcourt, W. D., Macfarlane, D. G., Robertson, D. A., Rea, B., and Spagnolo, M.: Observing the cryosphere with millimetre wave radar: The case study of Rhône Glacier, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-595, https://doi.org/10.5194/egusphere-egu2020-595, 2020.

The geometric characterization of riverbed material is fundamental piece of information for the management of river basins because it allows, for example, the determination of bed-load and hydrodynamics roughness and the study of geo-morphological phenomenona.
However information such the grading curve are not easily achievable by means of traditional field sampling methods, mostly intrusive, and to the hydraulic conditions of rivers that may have high water levels and strong flows.

Multibeam sonars represent an important alternative to traditional survey methods. Nowadays, thanks to advanced scientific knowledge, it is possible to make full use of an equipment increasingly accurate and precise. State of the art solutions have dimensions compact enough to be installed on remotly piloted vehicles and allow to obtained high resolution digital surface models of river beds. The feasibility of having models of such quality and the possibility to conduct surveys more frequently, allowing the monitoring of sedimentation and erosion phenomena as well as the dynamics of the armouring layer, have motivated the development of advanced and innovative technology to analyse these models.

The aim of this work is the development of a workflow that provides an effective method to characterize riverbed material. In order to achieve this target we start from an advanced and original survey technique, that allows to obtain high resolution digital surface models, and use an appropriate post-processing procedure.
We introduce first some results obtained from the analysis of digital surface models produced in laboratory or relative to well known site. In particular advanced techniques for the study of 3D model and the detection and geometric characterization of forms are investigated.
Then we present some data acquired at high resolution (few centimeters) with a multibeam sonar mounted on a remote controlled vessel. Field surveys were conducted in real fluvial environment with the aim of produce qualitative and quantitative information about the surface layer of riverbed.
Even considering some sources of uncertainty that may be present from field survey to modeling, the obtained results show how it is possible to identify and geometrically characterize several of the forms present on the surfaces analyzed. 

How to cite: Rover, S., Avancini, G., and Vitti, A.: Management and analysis of high resolution multibeam sonar surveys for geometry characterization of riverbed material, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-981, https://doi.org/10.5194/egusphere-egu2020-981, 2020.

EGU2020-10187 | Displays | GI1.3

Time-SIFT : a frugal method for leveraging multi-temporal photogrammetric data without ancillary data

Denis Feurer, Sean Bemis, Guillaume Coulouma, Hatem Mabrouk, Sylvain Massuel, Romina Vanessa Barbosa, Yoann Thomas, Jérôme Ammann, and Fabrice Vinatier

Latest advances in lightweight aerial platforms, miniaturized RTK DGPS positioning and IMUs make now it possible to build multitemporal photogrammetric datasets with centrimetric accuracies. Together with the increase of very high-resolution topographic data availability, algorithms that came from the computer vision community also provoked a marked resurgence of interest on archival photogrammetric data. Recently, Feurer and Vinatier (2018) proposed a method that rely on the invariance properties of the feature detection algorithms such as SIFT to estimate orientations in a single multi-temporal block. This method allows for an inherent co-registration of processed multi-temporal photogrammetric datasets and hence detection and mapping of 3-D change from past imagery. This work demonstrated that – in the case of archival aerial imagery – the Time-SIFT method enables the processing of multi-temporal photogrammetric imagery without ancillary data.

However, the potential of the Time-SIFT method had to be checked for in various contexts and spatio-temporal scales. More, the Time-SIFT method may allow to cope with the lack of precise positioning, in the case of image acquisitions made with frugal acquisition systems for instance. Hence this study proposes to apply the Time-SIFT method on five contrasting test cases. Their time and space scales vary from a domain of several square-centimeters to domains of several tens of kilometers, with time spans varying from the minutes to the decades. The test cases rely within different disciplines of geosciences, from soil science to vulcanology. Our works showed that the Time-SIFT methods succeeds through this whole range of spatio-temporal scales, and show even some unexpected robustness in context of strong changes due to vegetation and/or presence of water in coastal areas. These results demonstrate that the Time-SIFT method has a potential to tackle a wide variety of multi-temporal photogrammetric datasets, in particular in contexts where additional and calibration data are scarce.

How to cite: Feurer, D., Bemis, S., Coulouma, G., Mabrouk, H., Massuel, S., Barbosa, R. V., Thomas, Y., Ammann, J., and Vinatier, F.: Time-SIFT : a frugal method for leveraging multi-temporal photogrammetric data without ancillary data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10187, https://doi.org/10.5194/egusphere-egu2020-10187, 2020.

EGU2020-1744 | Displays | GI1.3

UAS radiation hot-spot detection and refinement

Kieran Wood, Dean Connor, Sevda Groen, Dave Smith, Sam White, Peter Martin, Yannick Verbelen, Erin Holland, Tom Richardson, and To Scott

Unoccupied Aerial Systems (UAS) are ideal tools for responding to nuclear incidents where large outdoor areas have become contaminated with a radiological hazard. They are advantageous because rapid response radiation surveys can be conducted while the human operator remains at a safe distance and avoids direct contamination of the platform. During fieldwork within the Chernobyl Exclusion Zone (Ukraine), an airborne platform was equipped with a GNSS enabled gamma spectrometer and used to survey an area surrounding a known highly contaminated building (a ‘hot-spot’), resulting in a radiation intensity map. The detected radiation pattern, however, was ‘blurred’ since the intensity recorded at any point counted nadir emissions, but also emissions from all sources within line-of-sight; The ‘hot-spot’ had an influence far outside its ground footprint. Methods exist to correct for errors introduced by varying terrain altitude, however, they do not remove the unwanted blurring. Hence, small point sources appear as broad regions of contamination which is entirely an artefact of the measurement process. The effect is further accentuated with increasing height above ground hence understanding and correcting for this phenomenon is particularly relevant to data collected using UAS. Here, we present a novel algorithm to refine the detected pattern to more accurately recover the ground-truth.

A forward model of the system is created which describes the relationship between the unknown ground-truth and the aerial measurements. Gamma ray emissions from a point source obey the inverse square law of spatial dilution and have an exponential attenuation in air. To model both effects, geometric information of the scene is required and is provided by the geotagged spectrometer data and photogrammetrically processed DEMs of the surveyed terrain. The resulting model is hyper-cube of linear equations, where every aerial measurement point is assumed to be influenced by every ground sample point. By finding the inverse solution of this system, the ground-truth radiation pattern is estimated in more detail. The Kaczmarz method is advantageous because a large system of equations can be broken down into smaller sub-routines and solved iteratively. A caveat is that the solution might settle to false positive. The refinement algorithm will be presented with simulated results, controlled laboratory experiments using robotic arms and sealed radioactive sources, and finally applied to a real-world data set collected in the Chernobyl Exclusion Zone.

How to cite: Wood, K., Connor, D., Groen, S., Smith, D., White, S., Martin, P., Verbelen, Y., Holland, E., Richardson, T., and Scott, T.: UAS radiation hot-spot detection and refinement, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1744, https://doi.org/10.5194/egusphere-egu2020-1744, 2020.

EGU2020-3134 | Displays | GI1.3

Geomorphological response to volcanic activity at Stromboli volcano using multi-platform remote sensing

Federico Di Traglia, Alessandro Fornaciai, Massimiliano Favalli, Teresa Nolesini, and Nicola Casagli

Steep volcano flanks are geomorphological systems highly responsive to both exogenous dynamics and endogenous forcing. While the external (gravitational) processes lead to a shift of material from steeper slopes to areas with lower gradients (erosion of loose deposits, rockfall of lavas/welded material), magmatic and tectonic activity can have either a constructional (accumulation) or a destructive effect (triggering moderate- to large-scale mass-wasting). Remotely sensed data have often been used to map areas affected by lithological and morphological changes, i.e. to identify areas impacted by eruptive and post-eruptive (landslides or floods) phenomena, as well as to quantify topographic changes.

In this work, the geomorphological evolution of the Sciara del Fuoco (SdF) depression on the Island of Stromboli (Italy) between July 2010 and October 2019 has been reconstructed by using multi-temporal, multi-platform remote sensing data. Digital elevation models (DEMs) from PLEIADES-1 tri-stereo images and from LiDAR acquisitions allowed the topographic changes estimation. Data comprised also high-spatial-resolution (QUICKBIRD) and moderate spatial resolution (SENTINEL-2) satellite images allowing to map areas affected by major lithological and morphological changes. SdF was selected being the optimal test-site for monitoring the effect of volcanic eruption on steep-slope volcano flank, since: i) it is affected by persistent volcanic activity, ii) it is prone to mass-wasting phenomena, and iii) it is one of the best studied and, among all, monitored volcano on Earth, providing exceptional validation data and ground-truth constrains.

During the analysed period, the volcano experienced two eruptions (summer 2014 and summer 2019), with the emplacement of two lava flow fields on the SdF. Before the 2014 effusion and in between the two eruptions, geomorphological changes consisted of volcanoclastic sedimentation and some overflows outside the crater. The effusive (and partially explosive) activity produced larger topographic changes, related to the emplacement of the two lava flow fields and to the accumulation of a volcaniclastic wedge on the SdF. This work shows that, at Stromboli, the emplacements of lava flow fields were preceded and accompanied by the accumulation of volcanoclastic wedges on the SdF. The quantification of these volcanoclastic wedges is relevant because they are composed of the same material that was involved in the 30 December 2002 tsunamigenic landslide, besides being located in the same area.

PLEIADES tri-stereo and LiDAR DEMs have been quantitatively and qualitatively compared, providing a first indication on the differences between two largely used methods for modelling topography. Although there are small artefacts in smaller ridges and valleys, there is still a clear consistency between the two DEMs for the main valleys and ridges. This analysis can be used by the volcanological community and the civil protection authorities in case of a cost-benefit analysis for planning the best method for updating topography and quantify morphological changes of an active volcano.

How to cite: Di Traglia, F., Fornaciai, A., Favalli, M., Nolesini, T., and Casagli, N.: Geomorphological response to volcanic activity at Stromboli volcano using multi-platform remote sensing, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3134, https://doi.org/10.5194/egusphere-egu2020-3134, 2020.

EGU2020-3930 | Displays | GI1.3

Role of discontinuities in spatial pattern of sea cliff erosion: case of a seaward dipping flysch cliff (Socoa, Basque Country, France)

Vincent Regard, Melody Prémaillon, Thomas J. B. Dewez, Nick J. Rosser, and Sébastien Carretier

Sea cliff shapes and erosion rates are controlled by several factors. Among them, rock resistance, whose strength results from lithology and rock structure, are pointed as major factors. Erosion is expected to focus on discontinuities where the rock mass is weakest (faults, fractures, joints and strata bounds), but understanding the control of discontinuities on the spatial and temporal pattern of erosion remains challenging. To analyze and quantify how rock structures control erosion, we monitored the evolution of a 400-m-long stretch of well-structured sedimentary cliffs: the Socoa cliff (Basque Country, France). The rock, known as the Socoa flysch formation, is a 45°-seaward-tilted, shore-parallel-striking, decimeter-thick repeating sequence of sandstone, mudstone, marl and limestone beds. Cliff-face erosion was observed and quantified using 6 ground-based Structure-from-Motion (SfM) surveys, spanning 5.7 years between 2011 and 2017.  To compare with longer term data, a multi-decadal (54 years) cliff-top retreat rate was also assessed using SfM-orthorectified archive aerial photographs spanning the period 1954-2008. During the ground-based survey, the 13 250 m² cliff face released 4500 blocks larger than 1.45*10-3 m3 for a total rock volume eroded of 170 m3. This rock lost volume equates to an average cliff retreat rate of 3.4 mm/yr. It is slightly slower than the 54 years-average cliff top retreat rate of 10.8 ± 1.8 mm/yr. In elevation, the maximum erosive activity is positioned about 2 m above high spring tides. The geographic position of rock scars is controlled by tectonic discontinuities. Alongshore, hot-spots of erosion are focused where major faults cross-cut the cliff face. Around these geographic hotspots, the depth of detached blocks is controlled by bed thickness, removing one or several beds at once. The surficial extent of detached blocks on the cliff-face is controlled by orthogonal secondary tectonic joint sets. These joints do not stop on lithological bed limits but rather on mechanical limits encompassing several lithological beds at once. As a process, we explain block detachment and cliff collapse by a cycle of erosion nucleation on discontinuities, radial erosion propagation around the nuclei and finally, cliff collapse crisis affecting the cliff top. We demonstrate that block production is concentrated around faults (nucleation) that focus erosion and allows for the radial development of sea caves close to cliff foot. Then, block production occurs mainly around those caves by radial detachment processes at free edges or fractures (propagation). It may lead, exceptionally, to high-magnitude events, during which slab collapse can affect the cliff from base to top (crisis).

How to cite: Regard, V., Prémaillon, M., Dewez, T. J. B., Rosser, N. J., and Carretier, S.: Role of discontinuities in spatial pattern of sea cliff erosion: case of a seaward dipping flysch cliff (Socoa, Basque Country, France), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3930, https://doi.org/10.5194/egusphere-egu2020-3930, 2020.

EGU2020-19847 | Displays | GI1.3

Close-range sensing and object-based analysis of shallow landslides and erosion in grasslands

Andreas Mayr, Martin Rutzinger, Magnus Bremer, and Clemens Geitner

Close-range sensing methods for topographic data acquisition, such as Structure-from-Motion with multi-view stereo (SfM-MVS) photogrammetry and laser scanning from the ground or from unmanned aerial systems (UAS), have strongly improved over the last decade. As they are providing data with sub-decimetre resolution and accuracy, these methods open new possibilities for bridging the gap between local in-situ observations and area-wide space-borne or aerial remote sensing. For assessments of shallow landslides and erosion patches, which are wide-spread phenomena in mountain grasslands, the potential of close-range sensing is two-fold: Firstly, it could provide accurate reference data for assessing the geometric accuracy of a catchment or regional scale eroded area monitoring based on aerial or satellite remote sensing systems. Secondly, selected sites can be monitored at a very detailed local scale to reveal processes of secondary erosion or natural vegetation succession and slope stabilisation. Furthermore, high-resolution 4D data from multi-temporal close-range sensing make it possible to quantify volumes and rates of displacement at erosion features. In this contribution, we propose to exploit this potential of close-range sensing for landslide and erosion studies with object-based approaches for raster and 3D point cloud analyses. Assuming that erosion features can be discriminated from undisturbed grassland and from trees and shrubs, based on their morphometric and spectral signatures, we show how computer vision and machine learning techniques help to detect and label these features automatically as spatial objects in the data. We combine this object detection and labelling with 2.5D differential elevation models and with 3D deformation analysis of point clouds. This strategy addresses one of the key challenges of automatically analysing close-range sensing data in geomorphological studies, i.e. linking geometric information (such as the size and shape of erosion features or the surface change across a time series) with semantic information (e.g. separating vegetation from complex ground structures). In three case studies from recent projects in the Alps, where we acquired data by UAS, terrestrial laser scanning and terrestrial photogrammetry, we demonstrate the use of these new methodological developments. The methods tested can reliably detect changes with minimum magnitudes of centimetre to decimetre level, depending primarily on the specific data acquisition setup. By automatically relating these changes to erosion features of different scales (i.e. both at entire eroded areas and at their components, e.g. collapsing parts of the scarp), such analyses can provide valuable insights regarding process dynamics. In our tests, close-range sensing and automated data analysis workflows helped to understand both the development of new eroded areas as well as their enlargement by secondary erosion processes or episodic landslide reactivation. Based on the experience from these case studies, we also discuss the main challenges and limitations of these methods for erosion monitoring applications.

How to cite: Mayr, A., Rutzinger, M., Bremer, M., and Geitner, C.: Close-range sensing and object-based analysis of shallow landslides and erosion in grasslands, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19847, https://doi.org/10.5194/egusphere-egu2020-19847, 2020.

EGU2020-1382 | Displays | GI1.3

Particularities of the current geographical area of Suceava county in the period preceding the imperial occupation

Cristian Ciubotaru, Vasile Efros, and Liliana Daniela Diacon

    The situation of the geographical map of Europe in the time interval precursor of the imperial occupation in Bukovina, was fueled by the change of the balance of forces. Territorial entities with unstable administration, depending on an imperial structure, have constituted a currency of exchange due to agreements independent of the will of the indigenous population. The upper country of Moldova did not benefit from a consistent geographical research, the first territorial representations stopped at the Carpathian mountains as a natural border of the Central European world. The first maps of Moldova are studied with a focus towards the north of the territory, identifying settlements with economic importance in the future region of Bukovina. Cutting some geographical elements represents an interest for the territorial entity in which the cartographic projection is edited.

    The objectives of the paper are: 1) geographical analysis of northern Moldova during the period preceding the occupation of the Habsburg Empire, 2) identifying the degree of geodemographic and economic homogeneity of northern Moldova, and 3) research of natural geographical factors in determining the reasons of Bukovina’s annexation.

    The paper highlights the period prior to the occupation, identifying geographical data about the Upper Country of Moldova, cartographic transpositions, geodemographic characteristics, economic aspects, travel impressions. These combined elements identify the degree of territorial homogeneity between the future region of Bukovina and the geographical area remaining as the principality of Moldova. The natural potential of the northwestern region of Moldova is identified in comparison with the rest of the territory. The geographical causes of the annexation of the north of Moldova are analyzed, identifying aspects other than those of spatial continuity with Galicia, geopolitical and administrative elements. The natural setting can be an element of harmony with the imperial center as a motivation for the occupation of colonization and harmonious integration of ethnic minorities.

     The Carpathian Mountains have been a long-standing eastern border for the expansion of Central-European powers. Looking at an imperial map it is found that Bukovina is in the eastern extremity that cuts the territory of Moldova in the northwest. The natural geographical area of Bukovina is identified as a miniature Austria, a mountainous area in the west with wide depressions and boreal landscape, and in the east a flat plateau favorable to agricultural crops. The temperate-continental climate with Scandinavian-Baltic shades may play a role of interest for an Anglo-Saxon people adapted to this type of climate. ,,The country of  beeches", reflects a geographical landscape being predominantly identifiable in western and central Europe. Natural resources are more important in terms of value and quantity compared to other regions of Moldova that have not entered the imperial sphere.

     The conclusions also involve a research of the degree of natural attractiveness in the motivation of occupying the northwestern part of Moldova. The research methodology involves the transposition of historical information into geographic data, comparative analysis and cartographic method.

  

Keywords: Bukovina, Moldova, geography, contrast.

How to cite: Ciubotaru, C., Efros, V., and Diacon, L. D.: Particularities of the current geographical area of Suceava county in the period preceding the imperial occupation, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1382, https://doi.org/10.5194/egusphere-egu2020-1382, 2020.

EGU2020-8231 | Displays | GI1.3

Multi-decadal (1953 – 2017) response of rock glacier morphodynamics to climate change in the Kauner Valley in the Ötztaler Alps, Austria based on historical aerial images and airborne LiDAR data

Fabian Fleischer, Florian Haas, Tobias Heckmann, Moritz Altmann, Livia Piermattei, Jakob Rom, and Michael Becht

Although the observed global climate change has particularly affected high-alpine regions and these geosystems seem to react very sensitively to changes in external forcing, there is a lack of understanding about the effect of a changing climate upon high-alpine landscapes at the timescale of decades.  In the case of rock glaciers, which are common features in high alpine periglacial landscapes, numerous studies suggest a general acceleration of rock glacier displacement rates accompanied by surface lowering. This behaviour has been attributed to the rising permafrost temperature, induced by atmospheric warming and regulated by thermo-hydrological processes. On the other hand, decoupled kinematics of nearby rock glaciers under the same climatic forcing have also been proven. This is attributed to different local topo-climatic conditions and genesis of the investigated rock glaciers.  To contribute to the understanding of multi-decadal rock glacier response to climate change, we investigate the morphodynamic changes for selected rock glaciers in the Upper Kauner Valley in the Ötztaler Alps, Austria, a catchment comprising numerous rock glaciers of different size, genesis, elevation, aspect and activity status. This is done for multiple time slices between 1953 and 2017. These changes are analysed with respect to rock glacier characteristics and changes in the meteorological forcing. This work is part of the interdisciplinary and multi-university research project SEHAG (Sensitivity of high alpine geosystems to climate change since 1850), which aims to investigate changes in different processes of alpine geosystems and their interaction.

In order to investigate morphodynamics of the rock glaciers, we use digital photogrammetry to generate orthophotos and digital elevation models from historical aerial images (available since 1953). Additionally, we use digital elevation models generated from three airborne LiDAR surveys within the period 2006-2017. While the diachronic analysis of digital elevation models predominantly addresses vertical surface changes, image correlation of multitemporal digital orthophotos yields information on rates of horizontal displacement. The results for the individual rock glaciers are compared to each other and to meteorological data of nearby weather stations to analyse the response of rock glaciers with different characteristics to changing climate forcing. 

How to cite: Fleischer, F., Haas, F., Heckmann, T., Altmann, M., Piermattei, L., Rom, J., and Becht, M.: Multi-decadal (1953 – 2017) response of rock glacier morphodynamics to climate change in the Kauner Valley in the Ötztaler Alps, Austria based on historical aerial images and airborne LiDAR data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8231, https://doi.org/10.5194/egusphere-egu2020-8231, 2020.

EGU2020-11150 | Displays | GI1.3

An open-source toolset for automated processing of historic spy photos: sPyMicMac

Robert McNabb, Luc Girod, Christopher Nuth, and Andreas Kääb

First launched in 1971, the KH-9 “Hexagon” reconnaissance satellites were operational until 1986. In addition to the high-resolution main cameras, the satellites had a secondary camera system, the mapping camera, which acquired images at approximately 6-10m ground resolution. These images, declassified in 2002, provide an unparalleled ability to extend records of elevation change over areas of the world where older data, typically from aerial photogrammetry, are missing, unavailable, or unreliable, including High Mountain Asia and the Arctic. These images are not, however, free from challenges. Storage and film processing have introduced warping into the images, and the large film format means that images are scanned in halves which must be precisely re-aligned for photogrammetric processing.

 

Building on previous efforts, we have developed an open-source toolset, based in python, that performs several of the steps necessary for processing digital elevation models (DEMs) from the raw imagery within MicMac. These include precise re-alignment based on dense keypoint detection, automated detection of the reseau field to aid in un-warping of the images, color balancing to increase contrast in low-contrast areas, and automated detection of ground control points using modern orthorectified satellite images such as Sentinel-2 and Landsat 8, and high-resolution digital elevation models such as ArcticDEM. Each of these tools interface with the MicMac photogrammetry software package that performs each of the steps necessary for DEM extraction.

 

We have tested this toolset on scenes from Alaska, Iceland, and Norway. Comparison to external elevation datasets such as NASA’s Ice, Cloud and Elevation Satellite (ICESat), ArcticDEM, and national elevation products yields agreement of better than 10 m root mean square error over stable terrain, even in mountainous areas. In particular, we obtain satisfactory results in remote areas where precise ground control measurements are difficult to obtain. This toolset provides the ability to easily extend records of precise elevation change in areas where very little historic data exist. In addition, the GCP matching routine can be used to process other air photo datasets, providing a useful tool for processing older photo archives.

How to cite: McNabb, R., Girod, L., Nuth, C., and Kääb, A.: An open-source toolset for automated processing of historic spy photos: sPyMicMac, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11150, https://doi.org/10.5194/egusphere-egu2020-11150, 2020.

EGU2020-22558 | Displays | GI1.3

PyTrx: a Python-based monoscopic terrestrial photogrammetry toolset for glaciology

Penelope How, Nicholas Hulton, Lynne Buie, and Douglas Benn

Terrestrial photogrammetry is a growing method for deriving measurements from contemporary and historical imagery of glacial environments, providing unique insights into glacier change at a high spatio-temporal resolution. However, the potential usefulness of terrestrial image data is currently limited by the unavailability of user-friendly toolsets that contain all the photogrammetry processes required. PyTrx is presented here as a Python-alternative toolset to widen the range of monoscopic photogrammetry (i.e. from a single viewpoint) toolsets on offer to the glaciology community. The toolset holds core photogrammetric functions for template generation, feature-tracking, object identification, image registration, and georectification (using a planar projective transformation model), which can be performed on both contemporary and historical imagery. Examples of PyTrx's applications are demonstrated using contemporary time-lapse imagery, including ice flow velocities, surface areas of supraglacial lakes and meltwater plumes, and glacier terminus profiles.

How to cite: How, P., Hulton, N., Buie, L., and Benn, D.: PyTrx: a Python-based monoscopic terrestrial photogrammetry toolset for glaciology, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22558, https://doi.org/10.5194/egusphere-egu2020-22558, 2020.

EGU2020-7826 | Displays | GI1.3

Coupling historical maps and Lidar data to recognize man-made landforms in urban areas

Martino Terrone, Guido Paliaga, Pietro Piana, and Francesco Faccini

In the last years there is growing interest on urban geomorphology both for the links with landscape planning and for its historical, cultural and scientific interest.

The identification of landforms in urban contexts is particularly difficult due to the progressive stratification of urban phases: the foundation of cities in the Mediterranean area dates back to ancient times and their growth in size is generally significant from the Middle Ages. This makes it frequent to find landforms which date back to more than 1000 years ago: they can be new, man-made landforms or modifications of natural ones, particularly coastal or fluvial features. Land modifications are particularly significant in the last 2 centuries, notably in the second half of the C19th and in the second half of the C20th, two periods identified as the potential start of the Anthropocene.

Anthropogenic terrain features are generally due to excavation and fill: unlike natural landforms which are generally identifiable through field surveys, the former require field observations, cartographical comparisons, multitemporal comparison of topographical views and historical photographs, geognostic investigations and geophysical surveys.

This research presents the results of a multitemporal analysis of the city of Genoa carried out by superimposing data from nineteenth-century historical cartography and topographical data from Remote Sensing.  The 1:2.000 scale map of Ignazio Porro, dating back to the first half of the C19th, has been digitalised on Lidar images from 2019 and with 1 m resolution, provided by Genoa Municipality. This methodology, developed with QGIS, has been applied on 5 sample areas particularly significant for their anthropogenic modifications: the area around Sant’Agata bridge in Val Bisagno, the area of Morandi Bridge in Val Polcevera, the road called Circonvallazione a Monte, the Promontory of the Lighthouse and the Via Digione area. Through the overlaying of multitemporal cartographies it was possible to identify and quantify with great precision excavation, landfill and mixed areas, allowing the identification of the most significant anthropogenic landforms. The obtained results have been validated through direct observations and supported by data from the geognostic regional database, revealing the potential of this approach for other urban areas.

How to cite: Terrone, M., Paliaga, G., Piana, P., and Faccini, F.: Coupling historical maps and Lidar data to recognize man-made landforms in urban areas, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7826, https://doi.org/10.5194/egusphere-egu2020-7826, 2020.

EGU2020-22512 | Displays | GI1.3

Use of WWI photos for quantitative reconstructions of glaciers along the Italian-Austrian front

Luca Carturan, Aldino Bondesan, Alberto Carton, Federico Cazorzi, Sara Cucchiaro, Jessica De Marco, and Livia Piermattei

The knowledge of past fluctuations of glaciers is the key for understanding their dynamics and their climate-related evolution. Glacier mass balance and length changes are the two metrics normally used for reconstructing past fluctuations series of glaciers. However, length change measurements series are often discontinuous and require validation, whereas mass balance measurements are available for only a few glaciers worldwide and only for the latest decades.

In the context of glacier reconstructions, other sources of information such as historical-archival, glacio-archaeological and geomorphological data are of critical importance, because they enable the completion and validation of direct measurement series and their extension into the past, providing spatial and temporal constraints.

A unique source of unexploited historical information dating back to the First World War (WWI, 1915-1918) exists for many glaciers in the Eastern Italian Alps. This information mainly consists of old photos, which however are spread over a multitude of sources, often difficult to access, and in many cases not yet digitized.

We propose a workflow that enables extracting quantitative information from terrestrial photographs taken during the WWI period, aimed at the reconstruction of glacier area, volume and firn lines by means of the monoplotting technique. This method relies on the availability of high-resolution digital elevation models, which became recently available over wide areas thanks to LiDAR and aerial photogrammetry. This work presents the methods applied, and the results obtained, on several case studies in the Adamello-Presanella, Ortles-Cevedale, Dolomites, and Julian Alps.    

How to cite: Carturan, L., Bondesan, A., Carton, A., Cazorzi, F., Cucchiaro, S., De Marco, J., and Piermattei, L.: Use of WWI photos for quantitative reconstructions of glaciers along the Italian-Austrian front, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22512, https://doi.org/10.5194/egusphere-egu2020-22512, 2020.

EGU2020-22543 | Displays | GI1.3

Topographic maps – an important data source for investigating long-term glacier variations

Bettina Knoflach, Clemens Geitner, and Johann Stötter

The mountain cryosphere has been disproportionally affected by climate warming and changing precipitation conditions since the 19th century. This has caused intense and multiple reactions in high mountain hydrosphere, lithosphere, reliefsphere, biosphere and pedosphere. Although there is general knowledge on climate-related changes of glaciers, little is known about the high-resoluted temporal and spatial development of glaciers in the last century. These knowledge gaps further implicate limitations by simulating past and future development of the mountain cryosphere difficult, as important calibration and validation data are missing.

Topographic maps contain important information, as they are among the most reliable area-wide representations of past landscape for the time before airborne data acquisition. Thus, they offer the opportunity to extract former glacier extents and to close the information gap between the LIA extent, reconstructed from moraine extent, and aerial derived glacier information in the recent past.

However, as maps represent entities of a real world generalized depending e.g. on the intension of mapping, we consider map uncertainties as a crucial aspect for the reconstruction of glaciers from historical data.

In order to assess the accuracy of glacier area and front position from topographic maps, we reconstruct glacier extents under consideration of a comprehensive systematic examination of the uncertainty with regard to position, time and attribute. For this purpose, we use information of 12 topographic maps with a scale of 1:75,000 or larger from Kaunertal, covering a time span of 139 years (1871 – 2010) and analyse the accuracy of the maps focusing on production-related and transformation-oriented uncertainty.

The comparison between the glacier changes, derived from the maps and the original data (if available) as well as those measured in situ, shows that topographic maps are a reliable data source for the reconstruction of glacier front variations and provide vital key information when studying long time series.

How to cite: Knoflach, B., Geitner, C., and Stötter, J.: Topographic maps – an important data source for investigating long-term glacier variations, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22543, https://doi.org/10.5194/egusphere-egu2020-22543, 2020.

EGU2020-22605 | Displays | GI1.3

Multi-temporal geomorphological maps based on historical aerial images for the investigation of geomorphic changes in an Alpine catchment

Tobias Heckmann, Livia Piermattei, Jakob Rom, Moritz Altmann, Fabian Fleischer, Florian Haas, and Michael Becht

Since the end of the Little Ice Age, alpine geosystems have been subject to changes due to the effects of ongoing climate change, affecting e.g. the cryosphere, topography, surface materials and morphodynamics, landcover, landuse, and other anthropogenic factors. Our work forms part of the SEHAG project that investigates the sensitivity of alpine geosystems to climate change during that period.

In order to identify and assess such changes, we aim at generating multi-temporal geomorphological maps of three alpine catchments (Upper Kaunertal, Horlachtal, Austria; Val Martello, Italy). In contrast to “traditional” geomorphological maps, we do not use areal, linear and point symbols to represent landforms, their properties, and geomorphic processes. Our approach is entirely based on non-overlapping polygon features that represent a landform- and process-centered subdivision of the catchment. This enables the analysis of the resulting map in a GIS framework with respect to the type, size and other properties of landforms. Most importantly, it allows for the assessment of their spatial configuration (adjacency, topology) within the catchment in terms of toposequences and sediment cascades.

Mapping is based on photogrammetric products of aerial photos, that are orthophotos, digital elevation models (DEMs) and derivatives of the latter. Furthermore, DEMs can be used for the orientation of historical terrestrial photographs, making them an additional mapping basis through monoplotting. Depending on the availability of imagery (area-wide aerial images dating back to the mid of the 20th century; local terrestrial photos starting from the second half of the 19th century), an area-wide geomorphological map representing the present state of the system forms the basis of our investigations. Historical images are then used to “update” the map back into the past wherever differences to the temporally subsequent situation are conspicuous. This especially regards the massive decline of glaciers, but also the build-up and depletion of storage landforms, the development of lakes, and changes in the channel network.

At a later stage, the maps will be used for a network-based, multitemporal assessment of sediment connectivity. Nodes represent landforms contained in the geomorphological map(s), and all kinds of evidence (visible features indicating sediment transfer between adjacent landforms, measurements based on DEMs of difference, connectivity indices) will be used to establish edges that represent (potential) sediment transfer by geomorphic processes. As the configuration of system components and/or the activity of processes changes between maps of subsequent epochs, these changes will affect connectivity measures of the corresponding network model.

How to cite: Heckmann, T., Piermattei, L., Rom, J., Altmann, M., Fleischer, F., Haas, F., and Becht, M.: Multi-temporal geomorphological maps based on historical aerial images for the investigation of geomorphic changes in an Alpine catchment , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22605, https://doi.org/10.5194/egusphere-egu2020-22605, 2020.

EGU2020-22519 | Displays | GI1.3

Between Land and Sea: An analysis of the landscape changes in the Chekka region (Lebanon) based on airborne LiDAR data and historical aerial images from 1962

Jakob Rom, Florian Haas, Manuel Stark, Andreas Poschenrieder, Karin Kopetzky, and Hermann Genz

The project “Between Land and Sea” was initiated by OREA (Institute for Oriental and European Archaeology) and is an interdisciplinary approach to combine the geology, geomorphology, and paleo-environment of the Chekka region (Lebanon) to investigate the ancient history and its archaeological remains. In the course of the project, the first ever scientific LiDAR (Light Detection and Ranging) data acquisition in Lebanon was conducted in autumn 2018 and a high-resolution DEM (Digital Elevation Model) was calculated. However, this model represents the recent topographical situation, which has changed drastically not only in the archaeologically relevant period up to 5000 years before today but also during the last decades.

To be able to qualitatively and quantitatively record geomorphological processes in the study area and thus understand long-term natural and anthropogenic landscape changes, the recent elevation model is compared with a historical model. The historical elevation model was derived on the base of aerial images of a French overflight from 1962. With the help of SfM (Structure from Motion/Agisoft Metashape) in combination with referencing methods (e.g. ICP), this historical model can be adapted to the LiDAR model. Quantitative analyses of selected areas provide information about surface changes over the last 56 years. But these results give also ideas about landscape evolution over longer time periods. Besides the natural changes, the historical model also reveals major anthropogenic changes since 1962 and shows that possible archaeologically relevant sites have been lost as a result of extensive overprinting due to the construction of buildings, infrastructure, industrial mining or agricultural use.

Our promising results show, that the implementation of historical terrain models based on aerial photographs can lead to a better understanding of the natural landscape development as well as anthropogenic induced changes and thus can also provide important additional information for archeological surveys.

How to cite: Rom, J., Haas, F., Stark, M., Poschenrieder, A., Kopetzky, K., and Genz, H.: Between Land and Sea: An analysis of the landscape changes in the Chekka region (Lebanon) based on airborne LiDAR data and historical aerial images from 1962, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22519, https://doi.org/10.5194/egusphere-egu2020-22519, 2020.

EGU2020-22544 | Displays | GI1.3

Multi-epoch bundle block adjustment for processing large dataset of historical aerial images

Camillo Ressl, Wilfried Karel, Livia Piermattei, Gerhard Puercher, Markus Hollaus, and Norbert Pfeifer

After World War II, aerial photography i.e. vertical or oblique high-resolution aerial images spread rapidly into civil research sectors, such as landscape studies, geologic maps, natural sciences, archaeology, and more. Applying photogrammetric techniques, two or more overlapping historical aerial images can be used to generate an orthophoto and a 3D point cloud, wherefrom a digital elevation model can be derived for the respective epoch. Combining results from different epochs, morphological processes and elevation changes of the surface caused by anthropogenic and natural factors can be assessed. Despite the unequalled potential of such data, their use is not yet fully exploited. Indeed, there is a lack of clear processing workflows applying either traditional photogrammetric techniques or structure from motion (SfM) with camera self-calibration. In fact, on the one hand, many SfM and multi-view stereo software do not deal with scanned images. On the other hand, traditional photogrammetric approaches require information such as a camera calibration protocol with fiducial mark positions. Furthermore, the quality of the generated products is strongly affected by the quality of the scanned images, in terms of the conservation of the original film, scanner resolution, and acquisition parameters like image overlap and flying height.

To process a large dataset of historical images, an approach based on multi-epoch bundle adjustment has been suggested recently.  The idea is to jointly orient the images of all epochs of a historical image dataset. This recent approach relies on the robustness of the scale-invariant feature transform (SIFT) algorithm to automatically detect common features between images of the time series located in stable areas. However, this approach cannot be applied to process digital images of alpine environments, characterized by continuous changes also of small magnitude that might be challenging to automatically identify in image space. In this respect, our method implemented in OrientAL, a software developed by TU Wien, identifies stable areas in object space across the entire time series. After the joint orientation of the multi-epoch aerial images, dense image matching is performed independently for each epoch. We tested our method on an image block over the alpine catchment Kaunertal (Austria), captured at nine different epochs with a time span of fifty years. Our method definitely speeds up the process of image orientation of the entire data set, since stable areas do not need to be masked manually in each image. Furthermore, we could improve the orientation of images from epochs with poor overlap. To estimate the improvements obtained with our methods in terms of time and accuracy of the image orientation, we compare our results with photogrammetric and commercial SfM software and we analyse the accuracy of tie points with respect to a reference Lidar point cloud. The work is part of the SEHAG project (project number I 4062) funded by the DFG and FWF.

How to cite: Ressl, C., Karel, W., Piermattei, L., Puercher, G., Hollaus, M., and Pfeifer, N.: Multi-epoch bundle block adjustment for processing large dataset of historical aerial images , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22544, https://doi.org/10.5194/egusphere-egu2020-22544, 2020.

EGU2020-2928 | Displays | GI1.3

Karst Topography Analysis Based on Multi-sensor (UAS & LiDAR) Data Acquisition

Aliki Konsolaki and Emmanuel Vassilakis

The state-of-the-art in surveying of open surface the last few decades is based on Point Cloud processing and interpretation. Lately, similar technology tends to be used for indoor surveying as well. One of the extreme applications is the use of the exact same technology in underground karstic cavities, evolving the methodology used in cave mapping. Geometric and morphometric analysis of the caves or any containing components (speleothems) include various techniques aiming at quantifying their dimensions in order to determine the characteristics and consequently the relationship between the cavity morphology and the surrounding structural, lithological and hydrogeological properties. The purpose of this research is to combine high resolution topographic data acquired with different instruments for both the underground morphology of a karstic cave (Koutouki, Peania, Greece) and the open-air surface above it. The described methodology is based on photogrammetric processing of Unmanned Aerial System image data and the extraction of a point cloud recorded with the use of a handheld laser scanning system. The latter resulted a 3D model of the cave and led to the production of a digital relief for the roof of the cave, which in turn was combined with the digital terrain model of the open-air surface above the cave. The final product is a high-resolution information layer with measurements of the rock thickness between the roof of the underground karstic structure and the open-surface topography with high accuracy.

How to cite: Konsolaki, A. and Vassilakis, E.: Karst Topography Analysis Based on Multi-sensor (UAS & LiDAR) Data Acquisition, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2928, https://doi.org/10.5194/egusphere-egu2020-2928, 2020.

EGU2020-18069 | Displays | GI1.3

Geomorphological and hydrological characterization of a meandering river by UAV and UWV applications

László Bertalan, Hannes Sardemann, David Mader, Noémi Mária Szopos, Bálint Nagy, and Anette Eltner

The Sajó River in Hungary is a medium-sized sand-bed river along which intensive meander development and bank erosion occur. The process threatens agricultural lands and populated areas extensively.  Therefore, preventive river management is needed.

Main geomorphological features, processes and in-channel flow conditions have to be studied in detail in order to reveal main driving factors. Datasets with high spatio-temporal resolution are necessary to identify relevant parameters. However, so far data density at this river is sparse and gauging stations are distributed poorly.

The aim of this study is the improvement of data availability to measure and model hydromorphodynamics of single reaches of the Sajó River. Therefore, multi-temporal field campaigns along selected sub-reaches are conducted with Unmanned Aerial Vehicles (UAV) and Unmanned Water Vehicles (UWV) to survey the topography, the river bed and flow conditions. The channel bathymetry is measured by a single-beam echo sounder mounted on a self-designed remotely controlled boat. The boat also integrates a Mobile Laser Scanner (MLS) to measure the river banks. Furthermore, a panorama camera system is installed to improve the pose estimation of the UWV functioning as a calibrated multi-sensor platform. UAV surveys were performed, using RGB and Thermal Infrared image sequences, to apply image velocimetry algorithms to characterize the river flow at selected cross-sections.  ADCP measurements and Terrestrial Laser Scans (TLS) are used for accuracy assessment of the novel datasets.

Eventually, data captured over a 2-years period will be implemented into hydrodynamic modeling of the studied sub-reaches to better understand seasonal variations in channel morphodynamics.

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The project has been founded by the DAAD (57448822) and (Tempus Public Foundation & DAAD 307670). The research is also influenced by the HARMONIOUS COST Action (CA16219).

How to cite: Bertalan, L., Sardemann, H., Mader, D., Szopos, N. M., Nagy, B., and Eltner, A.: Geomorphological and hydrological characterization of a meandering river by UAV and UWV applications, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18069, https://doi.org/10.5194/egusphere-egu2020-18069, 2020.

High resolution topographic models generated from repeat unmanned aerial vehicle (UAV) surveys and structure from motion (SfM) are increasingly being used to investigate landscape changes and geomorphic processes. Traditionally, accurate UAV surveys require the use of independently measured ground control points or highly accurate camera position measurements. However, in addition to accuracy in an absolute sense (how well modeled topography matches real topography), model quality can be expressed as accuracy in a comparative sense (the degree to which two models match each other). We present a simple SfM workflow for calculating pairs or sets of models with a high comparative accuracy, without the need for ground control points or a dGNSS equipped UAV. The method is based on the automated detection of common tie points in stable portions of the survey area and, compared to a standard SfM approach without ground control, reduces the level of change detection in our surveys from several meters to 10-15 cm. We apply this approach in a multi-year monitoring campaign of an 8 km stretch of coastal cliffs on the island of Rügen, Germany. We are able to detect numerous mass wasting events as well as bands of more diffuse erosion in chalk sections of the cliff. Both the cliff collapses and the diffuse erosion appear to be strongly influenced by antecedent precipitation over seasonal timescales, with much greater activity during the winter of 2017-2018, following an above average wet summer, than during the subsequent two winters, which both followed relatively dry summers. This points to the influence of subsurface water storage in modulating cliff erosion on Rügen.

How to cite: Cook, K. and Dietze, M.: UAV-derived change detection without ground control points, an example from the cliff coast of Rügen, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-11735, https://doi.org/10.5194/egusphere-egu2020-11735, 2020.

EGU2020-3459 | Displays | GI1.3

Terrestrial-Aerial-SfM and TLS data fusion for agricultural terrace surveys in complex topographic and land cover conditions

Sara Cucchiaro, Daniel J. Fallu, He Zhang, Kevin Walsh, Kristof Van Oost, Antony G. Brown, and Paolo Tarolli

In the last two decades, important developments in High-Resolution Topographic (HRT) techniques, methods, sensors, and platforms has greatly improved our ability and opportunities for the characterization of landscapes through sub-metric DTMs (Digital Terrain Models). The choice of the most appropriate platform for HRT surveys must consider the required resolution, the spatial extent, and the features present in the analysed area. In complex topography, inaccessible areas and vegetated environments, the use of a single HRT technique is constrained by several factors. Therefore, data fusion from different acquisition platforms can be a useful solution if we design appropriate workflows for survey planning, data acquisition, post-processing, and uncertainty assessment. We tested this approach in the production of detailed DTMs of ancient agricultural terracing on two sites, Soave (North-east of Italy) and Martelberg in Saint-Martens-Voeren (East Belgium); case study sites for the TerrACE archaeological research project (ERC-2017-ADG: 787790, 2018-2023; https://www.terrace.no/). Both sites presented complex topographic and landcover conditions: the presence of vegetation (common in ancient, often abandoned, terraces) that cover parts of the sub-vertical surfaces (e.g., vertical walls of terraces), steep slopes and large survey areas. Therefore, we carefully designed the data fusion of HRT techniques in order to overcome all these constraints and thereby represent detailed 3D-views of the study sites. An integrated approach employing ground-based and UAV Structure from Motion (SfM) photogrammetry was used to preserve fine-grained topographic detail (via ground-based photos) and capture flat terrace zones at large spatial scale (via UAV images); while terrestrial Laser Scanner (TLS) permitted the accurate survey of the highly vegetated areas and vertical terrace walls. In order to create the point-cloud fusion, a key aspect for consideration when planning the survey planning was the location and distribution of the Ground Control Points (GCPs) for SfM and TLS targets. These are essential for georeferencing and co-registering of the aggregate data during the final merge. In the inaccessible zones of the studied areas, where was impossible to locate the GCPs, we tested the direct georeferencing of the UAV images with differential GNSS, such as PPK (post-processing kinematic). The SfM-TLS technologies allowed us to accurately recognize the topographic features of the entire terrace areas. This point-clouds merge was impossible to obtain without post-processing steps as co-registration process and uncertainty analysis. Even if several studies highlight how co-registration is essential in order to correctly merge HRT data, it is often not addressed in post-processing workflows. In this study, we demonstrated how survey planning and co-registration were fundamental phases for data fusion and allowed us to obtained proper and reliable DTMs. These high-resolution DTMs provided a high level of detail of landscape that was useful to extract valuable information about ancient terrace complexes: morphological features, profiles, sections and scaled plans, simplifying and speeding the archaeologist's field and laboratory work.

How to cite: Cucchiaro, S., Fallu, D. J., Zhang, H., Walsh, K., Van Oost, K., Brown, A. G., and Tarolli, P.: Terrestrial-Aerial-SfM and TLS data fusion for agricultural terrace surveys in complex topographic and land cover conditions, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3459, https://doi.org/10.5194/egusphere-egu2020-3459, 2020.

A rock wall failure occurred along a major highway in south-eastern Norway, shutting down two lanes of traffic for an extended period of time while the road authority inspected and repaired the wall. It was desired to have a high-resolution digital surface model along a 215-m long section of the 34-m tall vertical rock wall that included the failure zone.

A Structure-from-Motion (SfM)-based methodology was selected to achieve the desired resolution on the rock wall face, as well as below the foot and above the head of the wall. Due to the proximity of the wall face to the remaining open lanes of traffic, it was not possible to survey the face of the wall using a remotely piloted aircraft system (RPAS). Therefore, a combined platform photogrammetric surveying technique was employed to ensure optimal photographic coverage and to generate the best possible model. Ground control points (GCP) were distributed and surveyed along the bottom and top of the wall and an RPAS was flown manually over the head of the wall to capture downward facing (nadir) images. A lift crane was also employed to capture images from elevations varying between 20–30 meters with a standoff distance of 15 meters from the wall. Finally, ground-based images were captured using a camera equipped with real-time GNSS from the top of the opposite rock wall (across the highway) with standoff distance of approximately 65 meters.

In total, over 800 images were ingested into a commercial SfM software package. The bundle adjustments were assisted by the GNSS-equipped camera locations and the surveyed GCP were imported to georeference the resulting model. The dense point cloud product was exported to a separate meshing software package for comparison with a second dense surface model that was derived from pre-existing images of the as-built condition of same rock wall face (prior to failure). By subtracting the post-failure model from the pre-failure model, a volume estimate of the material, that was mobilized during the failure, was determined.

The utility of the multi-platform survey technique was demonstrated. The combination of aerial and ground-based photographic surveying techniques provided optimal photographic coverage of the entire length of the rock wall to successfully derive high-resolution surface models and volume estimates.

 

 

Keywords: Structure-from-Motion, photogrammetry, digital surface model, natural hazards, ground control.

How to cite: Smebye, H., Salazar, S., and Lysdahl, A.: Combined aerial and ground-based Structure-from-Motion modelling for a vertical rock wall face to estimate volume of failure , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20471, https://doi.org/10.5194/egusphere-egu2020-20471, 2020.

EGU2020-4373 | Displays | GI1.3

Soil Water Content Variation Regression Analysis Using Hyperspectral Camera in Weathered Granite Soils

Hwan-hui Lim, Seung-Rae Lee, Enok Cheon, Deukhwan Lee, and Seungmin Lee

Soil water content is one of the most common physical parameters that cause landslides or debris flow. Therefore, it is of very importance to determine or predict the water content variation due to infiltration of rainfall quickly and non-destructively. This study investigates the hyperspectral informations in the visible near-infrared regions (VNIR, 400nm~1000nm) of different samples of granite soils possessing varying water contents. Totally 162 granite samples were taken from 3 mountain areas. A Partial Least Squares Regression (PLSR) analysis was applied to develop calibration models and prediction models.  In the water content variation prediction model, the Area of ​​Reflectance(Near-infrared, NIR) parameter was the most suitable parameter to determine the water content. The results demonstrate that the hyperspectral camera combined with the PLSR model can be a useful and non-destructive tool for the determination of soil water content variation in the weathered granite soils that could be applied to the evaluation of possible instable area in a mountain site.

How to cite: Lim, H., Lee, S.-R., Cheon, E., Lee, D., and Lee, S.: Soil Water Content Variation Regression Analysis Using Hyperspectral Camera in Weathered Granite Soils, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4373, https://doi.org/10.5194/egusphere-egu2020-4373, 2020.

Soil erosion represents one of the most significant environmental problems of the 21st century with severe impacts on terrestrial ecosystems. Traditionally, soil losses by water are determined by runoff plots in situ. Micro-scale devices (<1 m length) are commonly used to monitor soil erosion rates in comparative field studies. This is especially the case in ecological-pedological experiments, investigating e.g. the effect of plant characteristics on erosion processes. The small plot size allows to focus precisely on interrill processes with the smallest possible set of confounding factors and a high number of replications. However, the runoff plot method is labour- and time-intensive, sediment handling can be challenging and the measurement accuracy varies importantly with the applied control of the measurement setup.

To optimize the acquisition of small-scale erosion data from splash and interrill processes, digital methods become more and more of interest. Therefore, we compared the use of photogrammetry with a) terrestrial and b) airborne (UAV) single lens reflex (SLR) cameras as well as c) a terrestrial laser scanner (Leica Scanstation P40) to determine event-based initial erosion rates. Rainfall simulations with the Tübingen rainfall simulator and micro-scale runoff plots (0.4 m × 0.4 m) were conducted on two substrates: a Hortic Anthrosol and sieved sand (0.10-0.45 mm). Runoff plots were exposed to rainfall events with an intensity of 60 mm h-1. The measurements were repeated 5 times per substrate for each method and images of the runoff plot surfaces were captured before and after every event. The overlapping SLR images were processed in Agisoft PhotoScan (Structure from Motion - SfM) to process digital surface models (DSMs) with sub-millimetre resolution (a + b). Laser scans were processed with Leica Cyclone and ESRI ArcGIS (c). We assessed the volume of detached sediment by calculating the differences between multi-temporal DSMs or point clouds. After every rainfall simulation, the discharged sediment was weighed to derive the ground-truth for validation.

The results showed that photogrammetry with digital cameras as well as the use of laser scanners are principally suitable methods to create small-scale 3D point clouds and to map topography differences necessary for initial erosion rate calculation. The processing with common software systems, however, proves to be challenging and high precision is required for recording in the field. All methods overestimated the erosion rates with differences to the weighed sediment delivery from 14 to 45 %. The accuracy was higher for uniform sand than for the Anthrosol treatment. The SfM approach with digital cameras derived better results than the laser scanner used in this study. The terrestrial use of cameras was superior to the airborne use in this small-scale setup, because of the necessary flight altitude to avoid air turbulences on the soil surface. Further development of the measuring techniques and their precise application in the field as well as adapted software processing are still needed. Nevertheless, the methods tested show promising possibilities even for small-scale erosion measurements. Ideas and further suggestions on improvements will be presented at the EGU 2020.

How to cite: Seitz, S., Scholten, T., and Schmidt, K.: Soil erosion monitoring at small scales: Using close range photogrammetry and laser scanning to evaluate initial sediment delivery, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-16685, https://doi.org/10.5194/egusphere-egu2020-16685, 2020.

EGU2020-18252 | Displays | GI1.3

High-resolution photogrammetric methods for nested parameterization and validation of a physical-based soil erosion model

Lea Epple, Andreas Kaiser, Marcus Schindewolf, and Anette Eltner

Soil erosion is one of the most prominent environmental problems of major interest to a vast field of research. Due to the complexity, variability and discontinuity of erosional processes, erosion model approaches are non-transferable to different spatial and temporal scales.

The objective of our project is the across-scale modelling of soil erosion, using photogrammetric measurements and optimization methods as well as physical based model approaches. Present process-based models are only valid for the observation scale they are parametrized and validated for. In the observed reality phenomena therefore occur, which are not or only to some extent reproducible by complex model concepts (e.g. development of rills or concentrated runoff within driving lanes). We present the synergetic combination of a physically described model with highly redundant observations from photogrammetric data processing. This enables both the validation of the erosion model EROSION-3D as well as the optimization of its parameters and potentially advancement of the mathematical process description. The photogrammetric observations (RGB and thermal) offer the opportunity of a temporal and spatial differentiated process assessment (splash, sheet and rill erosion, as well as deposition and transport). To this purpose, the acquisition of the respective operating processes and contributing factors, will be nested defined at three different scales (micro plot, single slope and catchment scale) on two sites (loess soil and residual soil).

Flexible cross-scale applicable photogrammetric methods, considering 3D reconstruction and flow measurement, combined with physical-based methods of soil erosion modelling shall enable a better and reliable understanding of soil erosion processes on various spatial and temporal observation scales. Consequently, the implementation of the adjusted model is aimed for to enable a cross-scale description and validation of scale-dependent processes (e.g. discrete consideration of thin sheet flow and rill genesis) to offer new perspectives on both interconnectivity of sediment transport and relationship between event frequency and magnitude.

How to cite: Epple, L., Kaiser, A., Schindewolf, M., and Eltner, A.: High-resolution photogrammetric methods for nested parameterization and validation of a physical-based soil erosion model, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18252, https://doi.org/10.5194/egusphere-egu2020-18252, 2020.

EGU2020-18742 | Displays | GI1.3

Improving the use of laser scanning intensity data in complex 3D mapping of the cave environment: Case study of the Gouffre Georges Cave, France

Michaela Nováková, Michal Gallay, Jozef Šupinský, Eric Ferré, and Patrick Sorriaux

Terrestrial laser scanning (TLS) is frequently used for contactless acquiring of highly detailed and accurate three-dimensional (3D) representation of natural landscapes and man-made objects. The advantage of TLS has been exploited in mapping the underground landscapes such as caves formed in various geological settings with variable dimensions extending from narrow passage to grand domes. Highly detailed cave surveying with TLS generates millions of 3D coordinates of cave surface by which mapping of features difficult to be reached and studied directly is possible, e.g. speleothems, ceiling channels, structural rock properties and rock type alongside with the tectonic features influencing overburden stability. Besides the 3D coordinates, intensity of the backscattered laser pulse is recorded in the form of an additional attribute, influenced by various factors including spectral properties of the surface material. The studies published on the use of laser intensity have been mainly focused on the correction of intensity recorded by TLS for objects in the above-ground environment, where atmospheric attenuation, specifically humidity or dust content in the air, is negligible or it is considered constant during scanning. However, caves are specific due to their complex morphology and aerosol in their atmosphere. The presented case study focuses on these aspects in correcting the recorded intensity with a long range TLS Riegl VZ-1000 in the Gouffre Georges cave which formed on the contact of marble and lherzolite in the French Pyrenees. We present complex workflow for elimination of the influencing factors associated with the scanning geometry, including range and incidence angle, taking into account the character and contours of the cave wall surface as a set of facets and effect of atmospheric attenuation. The resulting corrected intensity value depends mostly on the spectral surface properties. Derived reflectance values revealed different lithological layers allowing to analyse their lithological and structural properties. Corrected intensity can be also used in biospeleological studies for mapping and quantification of cave fauna, in speleology for observing structures with higher occurrence of wet areas where active karst processes occur and even in archaeological studies for identification of cave paintings.

How to cite: Nováková, M., Gallay, M., Šupinský, J., Ferré, E., and Sorriaux, P.: Improving the use of laser scanning intensity data in complex 3D mapping of the cave environment: Case study of the Gouffre Georges Cave, France, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18742, https://doi.org/10.5194/egusphere-egu2020-18742, 2020.

GI2.1 – Applications of data, methods and models in geosciences

EGU2020-1243 | Displays | GI2.1

Use of Digital and 3D Visualisation Technology in Planning for Woodland Expansion

Chen Wang, Alessandro Gimona, Andrea Baggio Compagnucci, and Yang Jiang

Forests and woodlands offer many benefits to people. They can provide timber and food, store carbon to help deal with the effects of climate change, decrease flooding and soil erosion, and provide recreation for people and habitat for a multitude of species we care to conserve. Scottish forests cover roughly 19% of the country. The Scottish government has the ambition to add several thousand hectares a year over the next decades, to support the rural economy, the environment, and communities. It is important that a substantial proportion of the expansion is made up by native trees and shrub species due to better habitat for wildlife.

These challenges were explored with a case study of virtual forest landscape from Cairngorms National Park (CNP) which was used to test preferences for scenarios of future woodland expansion. Spatial Multi-criteria Analysis (sMCA) has been applied to decide where to plant new forests and woodlands, recognizing a range of land-use objectives while acknowledging concerns about possible conflicts with other uses of the land. The tools used in the development and implementation of the 3D model were PC and Mobile based, and enable the incorporation of interactive functionality for manipulating features. Model inputs comprise 5m DTM, 25cm Aerial Imagery, 3D Tree Species, GIS layers of Current Forest and Woodland Expansion inside CNP. Afforestation animation has been attached in Google My Maps. This is through setting different keyframes by storyboard camera path animation around the area of CNP. Stereo panorama has been applied to selection of woodland expansion scenarios (e.g. Broadleaved potential corridors, Conifer potential corridors), which is viewed with mobile technology and Virtual Reality (VR) equipment.

The 3D model with simulation of woodland expansion was used at the event of 2019 Royal Highland Show and European Forest Institute Annual Conference 2019. Audience feedback suggested the enhancement of user interaction through VR has potential implications for the planning of future woodland to increase the effectiveness of their use and contribution to wider sustainable ecosystems.

How to cite: Wang, C., Gimona, A., Compagnucci, A. B., and Jiang, Y.: Use of Digital and 3D Visualisation Technology in Planning for Woodland Expansion, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1243, https://doi.org/10.5194/egusphere-egu2020-1243, 2020.

EGU2020-5132 | Displays | GI2.1

Three-dimensional geological mapping and modelling at the Geological survey of Sweden

Eva Wendelin, Mehrdad Bastani, Lena Persson, Phil Curtis, Daniel Sopher, and Johan Daniels

How to cite: Wendelin, E., Bastani, M., Persson, L., Curtis, P., Sopher, D., and Daniels, J.: Three-dimensional geological mapping and modelling at the Geological survey of Sweden, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5132, https://doi.org/10.5194/egusphere-egu2020-5132, 2020.

EGU2020-20777 | Displays | GI2.1

On the potential and challenges of using machine-learning for automated quality control of environmental sensor data

Lennart Schmidt, Hannes Mollenhauer, Corinna Rebmann, David Schäfer, Antje Claussnitzer, Thomas Schartner, and Jan Bumberger

With more and more data being gathered from environmental sensor networks, the importance of automated quality-control (QC) routines to provide usable data in near-real time is becoming increasingly apparent. Machine-learning (ML) algorithms exhibit a high potential to this respect as they are able to exploit the spatio-temporal relation of multiple sensors to identify anomalies while allowing for non-linear functional relations in the data. In this study, we evaluate the potential of ML for automated QC on two spatio-temporal datasets at different spatial scales: One is a dataset of atmospheric variables at 53 stations across Northern Germany. The second dataset contains timeseries of soil moisture and temperature at 40 sensors at a small-scale measurement plot.

Furthermore, we investigate strategies to tackle three challenges that are commonly present when applying ML for QC: 1) As sensors might drop out, the ML models have to be designed to be robust against missing values in the input data. We address this by comparing different data imputation methods, coupled with a binary representation of whether a value is missing or not. 2) Quality flags that mark erroneous data points to serve as ground truth for model training might not be available. And 3) There is no guarantee that the system under study is stationary, which might render the outputs of a trained model useless in the future. To address 2) and 3), we frame the problem both as a supervised and unsupervised learning problem. Here, the use of unsupervised ML-models can be beneficial as they do not require ground truth data and can thus be retrained more easily should the system be subject to significant changes. In this presentation, we discuss the performance, advantages and drawbacks of the proposed strategies to tackle the aforementioned challenges. Thus, we provide a starting point for researchers in the largely untouched field of ML application for automated quality control of environmental sensor data.

How to cite: Schmidt, L., Mollenhauer, H., Rebmann, C., Schäfer, D., Claussnitzer, A., Schartner, T., and Bumberger, J.: On the potential and challenges of using machine-learning for automated quality control of environmental sensor data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20777, https://doi.org/10.5194/egusphere-egu2020-20777, 2020.

EGU2020-9590 | Displays | GI2.1

A new tracking algorithm for cyclones with tropical characteristics in the Mediterranean basin

Enrique Pravia-Sarabia, Juan José Gómez-Navarro, Juan Pedro Montávez, and Pedro Jiménez-Guerrero
Given their potential to damage coastal zones, cyclones with tropical characteristics have been profoundly studied, although their genesis and development mechanisms are not fully established yet. Being less severe and shorter than their tropical counterparts, the so-called medicanes are storms within the mediterranean basin with certain tropical characteristics. One of the most important factors that determine the impacts of these tropical-like storms is their trajectory. Thus, the detection and tracking algorithms have been object of numerous studies since the origins of numerical weather prediction.
 
Due to their similarities with tropical cyclones, the same algorithms should in principle be suitable for these Mediterranean storms, even if some minor changes become necessary considering that they differ in size, duration and intensity. Despite these similarities, there seems to be no consensus on the best algorithm for medicanes tracking. Although some of the existing specific algorithms for tropical cyclones are of a very high spatial accuracy, there are some difficulties that need further assessment and discussion when applying them to medicanes, such as the existence of more intense non-tropical systems within the domain of study, the coexistence of multiple medicanes or interferences due to large orographic barriers. The development of specific medicanes detection and tracking algorithms is not an unspoiled matter and some methods have been developed for this purpose. Nevertheless, their applicability is limited when the aforementioned adversities come into play.
 
Our aim is to propose and evaluate a new algorithm specifically suited for medicanes tracking, flexible, robust and able to detect and track them even in the mentioned adverse conditions. This algorithm consists in the implementation of a time independent methodology allowing the automated detection of simultaneous tropical-like cyclones within the same domain. It also provides the possibility of an easy modification of the cyclone definition parameters to make it useful for the detection of different cyclone types. The computational efficiency and time-saving performance are key factors to take into account for the development of this algorithm. Consequently, it should also be suitable for medicanes climatological studies.

How to cite: Pravia-Sarabia, E., Gómez-Navarro, J. J., Montávez, J. P., and Jiménez-Guerrero, P.: A new tracking algorithm for cyclones with tropical characteristics in the Mediterranean basin, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9590, https://doi.org/10.5194/egusphere-egu2020-9590, 2020.

EGU2020-20333 | Displays | GI2.1

Combining hyperspectral and XRF analyses to reconstruct high-resolution past flood frequency from lake sediments

Kévin Jacq, William Rapuc, Anne-Lise Develle, Pierre Sabatier, Bernard Fanget, Didier Coquin, Maxime Debret, Bruno Wilhelm, and Fabien Arnaud

Due to global climate changes, an intensification of extreme events such as floods is expected in many regions, affecting an increasing number of people. An assessment of the flood frequencies is then a public concern. For several years now, numerous studies are undertaken on geological paleoclimate records and especially on lake sediments to understand the fluctuations of the flood activities in contrasting climatic contexts and over long time periods. Flood events produce turbidity currents in lake basins that will usually lead to a normal graded detrital layer that differs remarkably from the continuous sedimentation. Currently, in an overwhelming majority of studies, once identified, the layers with the same characteristics (e.g. texture, geochemical composition, grain-size) are usually counted by naked-eye observation. Unfortunately, this method is time-consuming, has a low spatial resolution potential and can lead to accuracy bias and misidentifications. To resolve these shortcomings, high-resolution analytical methods could be proposed, as X-ray computed tomography or hyperspectral imaging. When coupled with algorithms, hyperspectral imaging allows automatic identifications of these events.

Here, we propose a new method of flood layer identification and counting, based on the combination of two high-resolution techniques (hyperspectral imaging and high-resolution XRF core scanning). This approach was applied to one sediment core retrieved from the Lake Le Bourget (French Alps) in 2017. We use two hyperspectral sensors from the visible/near-infrared (VNIR, pixel size: 60 µm) and the short wave infrared (SWIR, pixel size: 200 µm) spectral ranges and several machine learning methods (decision tree and random forest, neural networks, and discriminant analysis) to extract instantaneous events sedimentary signal from continuous sedimentation. The study shows that the VNIR sensor is the optimal one to create robust classification models with an artificial neural network (prediction accuracy of 0.99). This first step allows the estimation of a classification map and then the reconstruction of a chronicle of the frequency and the thicknesses of the instantaneous event layers estimated.  

High-resolution XRF core scanning (XRF-CS) analyses were performed on the same core with a 200 µm step. Titanium (Ti) and Manganese (Mn) were selected as a high-resolution grain size indicator and a redox-sensitive element that shows abrupt inputs of oxygenated water-related to floods, respectively. Both elements have thus been added to the model in order to refine the chronicle derived from hyperspectral sensors. The combination of both hyperspectral and XRF-CS signal indicator allows to decipher floods from instantaneous deposits (e.g slump). This combined chronicle is in good agreement with the expected frequency obtained from the naked-eye chronicle realized on the same core (r² = 0.8). In this study, we present for the first time, an innovative approach based on machine learning which allows to propose fast automatized flood frequencies chronicles. This work was assessed by traditional deposits observations, but it can be easily applied to very micrometric deposits, undistinguishable to the naked eye. Finally, this model can be implemented with other indicators. It then represents a promising tool not only for flood reconstructions but also for other paleoenvironmental issues.

How to cite: Jacq, K., Rapuc, W., Develle, A.-L., Sabatier, P., Fanget, B., Coquin, D., Debret, M., Wilhelm, B., and Arnaud, F.: Combining hyperspectral and XRF analyses to reconstruct high-resolution past flood frequency from lake sediments, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20333, https://doi.org/10.5194/egusphere-egu2020-20333, 2020.

            Fuzzy modelling of multisource geoscience data and its implications to mineral prospectivity mapping is drawing wide attention of the mineral exploration sector. Mineral deposits are basically end products resulted from optimal combination of certain metallogenetically favourable earth processes which leave their imprints in the associated geological entities at a range of scales that can be interpreted from their direct or indirect manifestation in several geospatial datasets. Therefore, in geologically potential yet under-explored or greenfield areas with no or very few discovered mineral deposits, the qualitative knowledge on the spatial relationship between mineralisation of interest and geoscience data could be an important guide to delineate exploration targets. In such a case, fuzzy set theory aided with Geographic Information System (GIS) is preferred as an effective mechanism for the transformation of subjective knowledge into quantitative information that further helps in modelling of earth science data.

            The Archaean to Paleo-proterozoic Sonakhan Greenstone Belt (SGB) located in the north-eastern fringe of the Baster Craton in central India is considered as a potential geological terrane for mesothermal gold mineralisation based on its geological and geochemical similarities with other mineralised greenstone belts. In this case study, a part of SGB has been taken as a target area that exposes sequence of metamorphosed mafic to ultramafics rocks and associated metasedimentary units in a gneissic country and younger granites. Since the study area represents a less explored terrane in terms of mineralisation, the objective of this research is to generate gold prospectivity maps using fuzzy logic modelling. A total of 17 multiclass evidential maps were generated using four independent geoscience datasets viz. geological, geochemical, geophysical, and remote sensing. The sources of data include existing databases from the Geological Survey of India (GSI) and published work along with the newly produced exploratory data in this research. Fuzzy membership values (0-1) were assigned to each class of evidential maps based on subjective judgement. The fuzzyfied evidential maps were then combined using fuzzy operators (AND, OR, SUM, PRODUCT, and GAMMA) through a series of logical steps i.e. the fuzzy inference network. Two different fuzzy inference networks were created using several combinations of fuzzy operations and accordingly, two prospectivity maps resulted which were classified as very high, high, moderate, low, very low favourable zones. To further enhance the result, the two maps were intersected to produce the final gold prospectivity map in support of targeting gold exploration in the region. A part of the study area, that is the Baghmara gold block, that was already identified as a gold enriched block based on traditional exploration works, coincides with the very high to high favourable zones predicted in the final map and this ensures the reliability of the gold prospectivity map and the efficiency of the adopted fuzzy logic approach in delineating promising targets for exploration.

How to cite: Behera, S. and Panigrahi, M. K.: Application of various fuzzy inference networks to integrate mineral exploration datasets: Implication for gold prospectivity mapping in Sonakhan greenstone belt, India, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7576, https://doi.org/10.5194/egusphere-egu2020-7576, 2020.

EGU2020-21002 | Displays | GI2.1

UAV-based digital image processing applied to the fossiliferous tanks prospection: insights at Guanambi region, northeast Brazil

José Magalhães, Gessica Pereira, Alexsander Leão, and Carolina Scherer

This study reveals the use of high resolution images collected by small Unmanned Aerial Vehicle (UAV) and Digital Image Processing (DIP) from Structure from Motion (SfM) technique applied to the prospection and geometric characterization of fossil tanks in the Guanambi region, located at Bahia state, Brazil. Geologically, the region is located in the Guanambi Batolith, composed of granites, migmatites and orthognaisses. In the research region for example, there was the Lagoa das Abelhas fossiliferous tank, which was previously excavated and in which bone fragments of various pleistocene mammal taxa, such as those of the order Xenarthra, were found, represented by sloths, glyptodonts and armadillos. Considering that there are no records of an effective scientific method to identify these features, the main objective of this work is to map the distribution of fossiliferous tanks excavated as well as those with prospective potential, and to estimate the geometries that they present through the use of the high resolution DIP. The Phantom 4 Advanced equipped with RGB 1’’ CMOS effective 20 M sensor were the UAV model type and camera used for conducting the flight plan. The Pix4D Capture was the tablet/smartphone application used for conducting the flight operation and image collection in an area with ​​80 ha. After this step, the images were submitted as DIP routines using the SfM technique from the Agisoft Metashape software, version 1.5.1. The DIP is divided into stages like point cloud calculation, 3D models generation from mesh and texture procedures, digital elevation model (DEM) and orthomosaic. With the integration of images (DEM and orthomosaic) it was possible to identify and delineate a total of 14 targets through geometric information such as surface area, length, width, depth and internal format. The configuration in relation to soil type, vegetation and rock outcrops was the same around the Lagoa das Abelhas fossil tank. After that, the team came back to fieldwork and found fossil fragments of three out of fourteen targets. Thus, this study could show the potential of using UAV to cover large areas directed to the prospecting part of fossiliferous tanks with good flight autonomy, low cost and fast data analysis. Some of the 11 targets can be prospected because they have a high prospective potential due to their similarity to past prospects which became sites for future paleontological prospection.

How to cite: Magalhães, J., Pereira, G., Leão, A., and Scherer, C.: UAV-based digital image processing applied to the fossiliferous tanks prospection: insights at Guanambi region, northeast Brazil, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21002, https://doi.org/10.5194/egusphere-egu2020-21002, 2020.

EGU2020-1538 | Displays | GI2.1

Pattern recognition of Seismic Activity in Indonesia through Deep Learning

Nishtha Srivastava, Kai Zhou, Jan Steinheimer, Johannes Faber, and Horst Stoecker

Earthquakes have disastrously impacted communities by destructing the buildings and infrastructure and creating substantial setbacks in the socio-economic development of a region in addition to the huge human loss. They are inevitable and considered extremely difficult to predict. Earthquake prediction research is being carried out for more than 100 years with no well acknowledged model achieved till date. However, the analysis of past seismic stress history of an active fault may help in understanding the stress build up and the local breaking points of the faults. Yet, analysing and interpreting the abundant seismological dataset is most time consuming and is a herculean task.

The possibilities to solve big data, complex problems with Deep Learning are undeniable, however, it’s usage in Seismology is still in its early stage. The implementation of Deep Learning algorithms has the potential to decipher the complex patterns and hidden information in past stress history that is nearly impossible for scientists. The careful implementation of various Deep Learning algorithms in the exponentially growing seismic data can significantly improve the Early Warning System. In the present study, we train a time efficient machine/deep learning algorithm to self-learn and decode the intricate stress accumulation and release pattern, to estimate the probability of local breakdowns of the fault.

The study region for the present research is Indonesia, which under the influence of the Eurasian, Indo-Australian, Philippine and Pacific plates, immensely suffers due to high seismic activity. The principal contributor in the seismicity of the region is Java-Sunda Trench which lies in the Pacific Ring of Fire (PROF). Owing to the high frequency of earthquakes striking every year from different epicentres, the region provides a huge database. The earthquakes triggering in the region from 1970-2018 is downloaded from the International Seismological Centre website (http://www.isc.ac.uk). These earthquake data comprised of ~270,000 events with the information of Latitude, Longitude, Time of the event and focal depth. To respect the bias which is unavoidable due to the change of the quality of the sensors and the data over the decades, the data is divided into subsets. We considered both small and large magnitude earthquakes along the subduction line to generate a localized time series of stress release to understand the seismic history of the region. By using different neural network models such as one dimensional Convolutional Neural Network (CNN), Recurrent Neural Network (RNN), an optimized Deep Learning algorithm is trained to understand the intricate pattern associated with the seismic stress release in region. This specialized model is expected to empower seismologist by providing a time saving, automated process for the identification of the zone of failures.

How to cite: Srivastava, N., Zhou, K., Steinheimer, J., Faber, J., and Stoecker, H.: Pattern recognition of Seismic Activity in Indonesia through Deep Learning, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1538, https://doi.org/10.5194/egusphere-egu2020-1538, 2020.

EGU2020-148 | Displays | GI2.1

Integrated Geophysical study on the subsurface structural characterization of West Beni Suef area, Western Desert, Egypt

Ahmed Khalil, Ahmed El Emam, Tharwat Abdel Hafeez, Hassan Saleh, and Waheed Mohamed

The aim of this work is to study the subsurface structures in the west Beni Suef area of the Western Desert in Egypt and to determine their effects on surface geologic structures. A detailed land magnetic survey has been carried out for the total component of the geomagnetic field using two proton magnetometers. The necessary corrections concerning daily variation, the regional gradient and time variations have been applied. Then, the total magnetic intensity anomaly map (TMI) has been constructed and transformed to the reduced to the pole magnetic map (RTP). The reduction-to-pole magnetic and Bouguer anomaly maps were used to obtain regional extensions of this subsurface structure. Regional–residual separation is carried out using the power spectrum. Also, Edge detection techniques are applied to delineate the structure and hidden anomalies. Data analysis was performed using trend analysis, Euler deconvolution, the results indicate that the area is affected by tectonic forces in the N-S, NW-SE, NE-SW and E-W trends, which are correlated with the directions of surface geologic lineaments. In addition, depths to the basement rocks have been estimated using spectral analysis technique. The computed depths have been used to construct the basement relief map which resulted from gravity and magnetic data. They show that the depth to the basement rocks ranges from 2.3 km to 4.7 km.

KEYWORDS
Land magnetic, Gravity, Euler deconvolution, Edge detection and Spectral analysis.

How to cite: Khalil, A., El Emam, A., Abdel Hafeez, T., Saleh, H., and Mohamed, W.: Integrated Geophysical study on the subsurface structural characterization of West Beni Suef area, Western Desert, Egypt, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-148, https://doi.org/10.5194/egusphere-egu2020-148, 2020.

EGU2020-303 | Displays | GI2.1

Characterization of human behavior in records of personal solar ultraviolet exposure records

David Jean du Preez, Suzana Blesic, Caradee Y. Wright, Djordje Stratimirovic, Jelena Ajtic, Martin Allen, and Hassan Bencherif

We investigated scaling properties of measurements of personal exposure to solar ultraviolet radiation (pUVR) using the 2nd order detrended fluctuation analysis (DFA2) and the wavelet transform spectral analysis (WTS). Studies of pUVR are important to identify populations at-risk of excess and insufficient exposure given the negative and positive health impacts, respectively, of time spent in the sun. These very high frequency recordings are collected by electronic UVR dosimeters. We analyzed sun exposure patterns of school children in South Africa and construction workers and work site supervisors in New Zealand, and we found scaling behavior in all our data. The observed scaling changed from uncorrelated to long-range correlated with increasing duration of sun exposure. We found peaks in the WTS spectra that mark characteristic times in pUVR behavior, which may be connected to both human outside activity and natural (solar) daily cycles. We further hypothesized that the WT slope would be influenced by the duration of time that a person spends in continuum outside and addressed this hypothesis by using an experimental study approach. To that end we performed combined DFA2-WTS analysis on a subset of individual records taken on the same day under very similar outdoor conditions and used the theoretical superposition rule provided by systematic assessments of effects of trends and nonstationarities on DFA2 as a methodological mean to trace and subsequently model human behavioral patterns in pUVR time series.

How to cite: du Preez, D. J., Blesic, S., Wright, C. Y., Stratimirovic, D., Ajtic, J., Allen, M., and Bencherif, H.: Characterization of human behavior in records of personal solar ultraviolet exposure records, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-303, https://doi.org/10.5194/egusphere-egu2020-303, 2020.

EGU2020-4260 | Displays | GI2.1

Seismic attribute mapping of a fluvial reservoir in Rhourde Chegga field (Hassi Messaoud, Algeria)

Nasrine Medjdouba, zahia benaissa, and amar boudella

Rhourde Chegga field is located in the north of Hassi Messaoud giant field, Algeria. The main hydrocarbon-bearing reservoir in Rhourde Chegga field is the lower Triassic Argilo-Gréseux reservoir. The Triassic sand is deposited as fluvial channels and overbank sands with a thickness ranging from 15 to 20 m, lying unconformably on the Paleozoic formations. Lateral and vertical distribution of the sand bodies makes their mapping very difficult and, sometimes, even impossible with conventional seismic interpretation. 

To better define drilling targets within the Triassic sand in the Rhourde Chegga field, 3D stratigraphic seismic attribute analysis was performed along the reservoir level, using PSTM and mid angle stack seismic data. By combining various attributes (RMS amplitude, half energy, variance, etc.), the channelized feature has been clearly imaged and delineated on the horizon slices and the volume extraction. The relationship between the combined seismic attributes and reservoir properties at well locations showed a good correlation.

Based on this study, about ten produced wells have been successfully drilled, confirming the efficiency of seismic attribute analysis to predicted channel body geometry.

Keywords: Channel, Attributes, Amplitude, Fluvial reservoir.

 

How to cite: Medjdouba, N., benaissa, Z., and boudella, A.: Seismic attribute mapping of a fluvial reservoir in Rhourde Chegga field (Hassi Messaoud, Algeria), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4260, https://doi.org/10.5194/egusphere-egu2020-4260, 2020.

Geochemical anomalies are an important indicator in prospecting. In particular, geochemical anomalies of Cu play a very important role in geological prospecting of minerals. Geochemical anomalies of Cu are mainly related to mafic-ultramafic rocks and porphyry bodies, which are also associated with ore-forming elements of the Co-Zn-Cr-Ni-Cu combination. The conventional technique of geochemical prospecting involves superimposition of element symbols (Au, Fe, Cu, Al, Ca, etc.) on the geological map of an area by analysing geochemical anomalies using geochemical data. However, this technique is not suitable for regions where geochemical anomaly data are limited. The development of hyperspectral remote sensing has enabled the mapping of spectral features related to characteristic absorption bands of elements in minerals at high spatial resolution, providing a means for precise and detailed reconstructions of geochemical anomalies facies (surface). Compared to conventional techniques for identifying elements, reflectance spectroscopy offers a rapid, inexpensive, and non-destructive tool for determining the mineralogy of rock and soil samples. Hyperspectral remote sensing also provides data for prospecting in areas without sufficient geochemical data, and thus is of vital significance in prospecting for ores in such regions. However, approaches for remotely sensing elements are still lacking, particularly for element content. In this study, a level analysis of Cu content via spectral indices in the northwestern Junggar region, Xinjiang, was conducted. Based on four levels (0–100 ppm, 100–1000 ppm, 1000–10000 ppm, and >10000 ppm) of Cu content and corresponding spectral reflectance, simple and useful spectral indices for estimating Cu content at different levels were explored. The best wavelength domains for a given type of index were determined from four types of spectral indices by screening all combinations using correlation analysis. The coefficient of determination (R2) for Cu was calculated for all indices derived from the spectra of rock samples and was found to range from 0.02–0.75. With sensitive wavelengths and a significant correlation coefficient (R2 = 0.63, P < 0.005), the Normalized Difference (ND)-type index was the most sensitive to Cu content exceeding 10000 ppm. Although the ND-type index has a few limitations, it is a useful, simple, and robust indicator for determining Cu at high concentrations. With the advent of new platforms and satellites in the future, such relationships with other elements are required to enable the widespread use of this index in broad-scale surveys of mineral elements in the field.

How to cite: Shanshan, W. and Kefa, Z.: Study on the Geochemical Anomaly of Copper Element Based on Hyperspectral Indices, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6433, https://doi.org/10.5194/egusphere-egu2020-6433, 2020.

EGU2020-6503 | Displays | GI2.1

Estimation and validation of electric power output from a fixed-type floating photovoltaic system

Jangwon Suh, Sungmin Kim, and Yosoon Choi

An accurate estimation of electric power production (EPP) is a crucial first step to design a floating photovoltaics (PV) project. This study estimates the EPP of a floating PV system and validates the results by comparing with the actual EPP observed at the Hapcheon Dam, Korea. Typical meteorological year data and system design parameters were entered into System Advisor Model (SAM) software to estimate the hourly and monthly EPPs. Three-year average observed EPPs (2012, 2013, and 2015) were used as reference values for the validation. The results showed the seasonal EPPs were the highest in spring and the lowest in winter. The monthly estimated EPPs were lower than the monthly observed EPPs. These results are ascribed to the fact the SAM was unable to consider the natural cooling effect of the water environment on the PV module. The error results showed it was possible to estimate the monthly EPPs with an error of less than 15% simply by simulation. However, it may possible to estimate the monthly EPPs with an error of approximately 9% when considering empirical results: The floating PV efficiency was approximately 1.1 times (110%) the overland PV efficiency. This indicates that the approach of using empirical results can provide reliable monthly estimation of EPP in feasibility assessment stage of floating PV projects.

How to cite: Suh, J., Kim, S., and Choi, Y.: Estimation and validation of electric power output from a fixed-type floating photovoltaic system, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6503, https://doi.org/10.5194/egusphere-egu2020-6503, 2020.

Combining multi-source data can improve the accuracy and the spatial resolution of the three-dimensional (3-D) displacements field. How to effectively integrate multi-source data to obtain high-precision and high spatial resolution 3-D displacements field is worthy of further study. The stochastic model and fusion model of integrating multi-source data affect the accuracy of data fusion. In this paper, based on the least squares method, the effects of different stochastic models and data fusion models on the 3-D displacements field’s accuracy are studied. The optimal method for estimating large-scale 3-D displacements field from integrated InSAR, leveling and GPS measurements is obtained. Then we realize the integrating InSAR, leveling and GPS measurements to obtain the high-precision 3-D displacements velocity field in Tianjin(China) from 2016 to 2018. The results are validated with GPS measurements at 6 independent stations, with the root mean squares (RMS) residuals of the discrepancies being 2.39mm/yr、2.54mm/yr and 2.83mm/yr in eastern, northern and vertical directions, respectively. By comparing different stochastic models, the 3-D displacements field obtained from multi-source data is optimized by the variance component estimation-least squares method, which is better than weighted least squares (WLS) method. By comparing different data fusion models, the accuracy of the horizontal displacements velocity is better than that of interpolated GPS results. The horizontal displacements component has a great influence on the vertical displacements velocity accuracy in the process of acquiring the 3-D displacements velocity by integrating InSAR, GPS and leveling measurements. This study provides a reference method for integrating multi-source data to obtain 3-D displacements field. This method effectively utilizes the advantages of GPS, InSAR and leveling measurements, and extends the limitations of single technical in describing surface-time scale applications. The 3-D displacements information with a large spatial scale and high spatial resolution provide a reliable data basis for studying the crustal movement and its dynamic mechanism.

How to cite: Guo, N.: Influence of Different Data Fusion Methods on the Accuracy of Three-Dimensional Displacements Field , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6601, https://doi.org/10.5194/egusphere-egu2020-6601, 2020.

EGU2020-7204 | Displays | GI2.1

3D geological models from combined interpretation of airborne-TEM and geological data- Two examples from Sweden

Mehrdad Bastani, Lena Persson, Peter Dahlqvist, Eva Wendelin, and Johan Daniels

The geological survey of Sweden (SGU) has carried out several detailed airborne TEM (Transient Electromagnetic) surveys in recent years. The data collected in these surveys were inverted to provide models of the resistivity of the subsurface, down to a few hundred meters depth. These resistivity models together with the data from existing boreholes and ground observations offer an excellent basis for further 3D geological modeling. 

The airborne TEM data presented in this study were collected between 2013 and 2016, covering large areas of the islands of Öland and Gotland, in Sweden. Both islands face problems with water supply due to limited groundwater resources. The aim of the surveys was to identify new groundwater resources, specify the depth to saline groundwater and to improve the understanding of the geology of the islands. On Öland, the Paleozoic sedimentary succession reaches thicknesses of approximately 250 m and is composed of Lower Cambrian sandstone, Middle Cambrian siltstone, and claystone followed by the Alum Shales of Upper Cambrian and Lower Ordovician age. Above this lies an up to 40 m thick Lower Ordovician limestone succession, which forms the bedrock at the surface across much of the island. The entire sedimentary sequence rests on Precambrian crystalline rocks. On the Island of Gotland, Silurian bedrock represents the upper part of a 250-800 m thick Paleozoic sequence overlying the crystalline basement. The Silurian bedrock is dominated by interbedded layers of limestone and marlstone, where the interface between limestone and marlstone is often the primary hydraulic conductor.

After acquisition, these data were processed and inverted (1D inversions with lateral constraints), to provide a series of large airborne datasets, providing a resistivity image down to depths of about 250 m in some areas. The considerable resistivity contrast between lithologies, e.g. limestone and marlstone on Gotland, provided an excellent opportunity to resolve boundaries between the different rock types. Borehole information, geological maps, ground geophysical data and the inversion results were incorporated in a 3D geological modelling software. On comparison of the airborne models, ground geophysical data and borehole information it was clear that the airborne resistivity models correlated well with the other available data. Hence, the resistivity models were used as the basis for constructing the 3D hydrogeological and geological models over significant parts of the islands. In this study we present the 3D geological models over the islands of Öland and Gotland which were constructed from the integrated interpretation of all the available data. The models are composed of voxels, each representing a certain lithology classified using a statistical approach. The classification is based on the resistivity range, distance to the neighboring wells/boreholes and the geological observations at the surface. The 3D voxel models will be/have been utilized in hydrological modelling, societal planning, and groundwater management.

How to cite: Bastani, M., Persson, L., Dahlqvist, P., Wendelin, E., and Daniels, J.: 3D geological models from combined interpretation of airborne-TEM and geological data- Two examples from Sweden, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7204, https://doi.org/10.5194/egusphere-egu2020-7204, 2020.

EGU2020-7516 | Displays | GI2.1

3D geological model of the Gråbo site from ground TEM measurements

Daniel Sopher, Eva Wendelin, Lars-Ove Lång, Johan Öhman, and Andreas Lindhe

A 3D geological model was constructed for the Gråbo site to investigate its suitability for artificial groundwater infiltration, to provide drinking water. The modelling work was performed by the Geological Survey of Sweden (SGU) as part of ongoing groundwater investigations. The site is located close to the city of Gothenburg, in western Sweden. A relatively thick succession of coarse-grained glaciofluvial sediment is located at the site, which overlies a typically finer grained and more clay rich sequence. Previously, the site has been the target of several investigations, the most extensive of these was performed in 2006, where a range of geophysical (seismic refraction, ground penetrating radar and resistivity) and borehole measurements were conducted. Based on previous studies the upper course-grained layer has the best potential for infiltration. However, although these investigations improved the understanding of the site, significant uncertainty remained as to the geometry of the upper course grained layer away from borehole locations.

In order to improve the understanding of the site, additional data was collected in 2018 using a tTEM (towed transient electromagnetic) system developed by Aarhus university. The system is comprised of a transmitter and receiver coil, which are towed behind an ATV (all terrain vehicle). Using the tTEM data a 3D resistivity model of the subsurface was generated down to a depth of between 50 and 70 m at the Gråbo site. On comparison with the available borehole data, it was clear that the course-grained layer could be mapped with relatively high accuracy as a region of high resistivity. The tTEM data was combined with the pre-existing geophysical and borehole data to construct both a voxel and layer-based model of the site. These 3D models have subsequently been used as part of ongoing efforts to evaluate the suitability of the site for infiltration (for example, to decide the location of additional investigation boreholes and to provide input to hydrogeological modelling). In this study we present the tTEM data and the 3D geological model. Finally, we exemplify how the 3D model has been used in subsequent investigations and decision making.

How to cite: Sopher, D., Wendelin, E., Lång, L.-O., Öhman, J., and Lindhe, A.: 3D geological model of the Gråbo site from ground TEM measurements, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7516, https://doi.org/10.5194/egusphere-egu2020-7516, 2020.

EGU2020-8383 | Displays | GI2.1

IGMAS+ – a tool for interdisciplinary 3D potential field modelling of complex geological structures.

Sabine Schmidt, Denis Anikiev, Hans-Jürgen Götze, Àngela Gomez Garcia, Maria Laura Gomez Dacal, Christian Meeßen, Christian Plonka, Constanza Rodriguez Piceda, Cameron Spooner, and Magdalena Scheck-Wenderoth

We introduce a new approach for 3D joint inversion of potential fields and its derivatives under the condition of constraining data and information. The interactive 3D gravity and magnetic application IGMAS (Interactive Gravity and Magnetic Application System) has been around for more than 30 years, initially developed on a mainframe and then transferred to the first DOS PCs, before it was adapted to Linux in the ’90s and finally implemented as a cross-platform Java application with GUI called IGMAS+. The software has proven to be very fast, accurate and easy to use once a model has been established. Since 2019 IGMAS+ has been maintained and developed in the Helmholtz Centre Potsdam – GFZ German Research Centre by the staff of Section 4.5 – Basin Modelling and ID2 – eScience Centre.

The analytical solution of the volume integral for the gravity and magnetic effect of a homogeneous body is based on the reduction of the three-folded integral to an integral over the bounding polyhedrons (in IGMAS polyhedrons are built by triangles). Later the algorithm has been extended to cover all elements of the gravity tensor as well. Optimized storage enables very fast inversion of densities and changes to the model geometry and this flexibility makes geometry changes easy. The geometry is updated and the gravity is recalculated immediately after each change. Because of the triangular model structure, IGMAS can handle complex structures (multi Z surfaces) like the overhangs of salt domes very well. Geophysical investigations may cover huge areas of several thousand square kilometers but also models of Applied Geophysics at a meter scale. Due to the curvature of the Earth, the use of spherical geometries and calculations is necessary.

The model technique is user-friendly because it is highly interactive, operates ideally in real-time whilst conserving topology and can be used for both flat (regional) and spherical models (global) in 3D. Modeling is constrained by seismic and structural input from independent data sources and is essential toward true integration of 3D thermal modeling or even Full Waveform Inversion. We are close to the demand for treating all geophysical methods in a single model of the subsurface and aim of fulfilling most of the constraints: measurements and geological plausibility.

We demonstrate the flexibility of the software by modeling: (1) the southern segment of the Central Andes which is designed to assess the relationship between the characteristics of the overriding plate and the deformation and dynamics of the subduction system; (2) the South Caribbean margin which defines the two flat-slab subductions of the Nazca Plate and the Caribbean Plate, with variable mantle density distribution implemented by voxels; (3) the North Patagonian Massif Plateau in Argentina which provides insight into the main height differences between the plateau and the surroundings; and (4) an Alpine model which interrogates the strength of the lithosphere at different locations through the Alps and their forelands.

How to cite: Schmidt, S., Anikiev, D., Götze, H.-J., Gomez Garcia, À., Gomez Dacal, M. L., Meeßen, C., Plonka, C., Rodriguez Piceda, C., Spooner, C., and Scheck-Wenderoth, M.: IGMAS+ – a tool for interdisciplinary 3D potential field modelling of complex geological structures., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8383, https://doi.org/10.5194/egusphere-egu2020-8383, 2020.

EGU2020-12546 | Displays | GI2.1

Application of multi-sensor unmanned aerial system for identification of hydrothermal alteration zones

Yosoon Choi, Jieun Baek, Jangwon Suh, and Sung-Min Kim

In this study, we proposed a method to utilize a multi-sensor Unmanned Aerial System (UAS) for exploration of hydrothermal alteration zones. This study selected an area (10m × 20m) composed mainly of the andesite and located on the coast, with wide outcrops and well-developed structural and mineralization elements. Multi-sensor (visible, multispectral, thermal, magnetic) data were acquired in the study area using UAS, and were studied using machine learning techniques. For utilizing the machine learning techniques, we applied the stratified random method to sample 1000 training data in the hydrothermal zone and 1000 training data in the non-hydrothermal zone identified through the field survey. The 2000 training data sets created for supervised learning were first classified into 1500 for training and 500 for testing. Then, 1500 for training were classified into 1200 for training and 300 for validation. The training and validation data for machine learning were generated in five sets to enable cross-validation. Five types of machine learning techniques were applied to the training data sets: k-Nearest Neighbors (k-NN), Decision Tree (DT), Random Forest (RF), Support Vector Machine (SVM), and Deep Neural Network (DNN). As a result of integrated analysis of multi-sensor data using five types of machine learning techniques, RF and SVM techniques showed high classification accuracy of about 90%. Moreover, performing integrated analysis using multi-sensor data showed relatively higher classification accuracy in all five machine learning techniques than analyzing magnetic sensing data or single optical sensing data only.

How to cite: Choi, Y., Baek, J., Suh, J., and Kim, S.-M.: Application of multi-sensor unmanned aerial system for identification of hydrothermal alteration zones, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12546, https://doi.org/10.5194/egusphere-egu2020-12546, 2020.