After its long reputation as an extremely polluted water river and anthropogenic mining waste dump, studies support Rio Tinto (southern Spain, Iberian Pyrite Belt) to be an extremely acidic environment where life relentlessly thrived long before human history. It has become clear that in this extreme environment, there are strong relationships between living and nonliving components at the microscale, resulting in the formation of micro-niche-based ecosystems. The site has therefore become a terrestrial analog of first interest for astrobiological and planetary science studies in terms of the search for life on Mars. The acidic environment is the product of the chemolithotrophic activity of microorganisms aggressively targeting sulfides (pyrite, chalcopyrite), here abundant, causing the leaching of iron and sulfur. This contributes to the formation of a variety of minerals, mainly gypsum, jarosite, goethite, and hematite, all of which have been detected on the Red Planet. 

Identifying and discretizing sulfides and iron-bearing sulfates from orbit and landed missions has been a relevant method for searching for life on Mars, notably distinguished by its iron-sulfur-rich composition. Similar mapping sulfide and sulfate distributions on easy-to-access terrestrial analog are critical to improving our ability to interpret data from other worlds and contextualize astrobiological observations.  

In this work, we present the spectroscopic analysis of remote sensing data over Rio Tinto, focusing on mapping the distribution of sulfides and sulfates as a proxy for the presence of biosignatures. We have studied multi- and hyper-spectral data from orbital and airborne spectrometers, cross-checking evidence from different datasets.   

The results of our work have been cartographically formatted and served to support the geologic mapping fieldwork campaign held at the Rio Tinto in November 2023.

How to cite: Panza, G., Frigeri, A., Skinner, J., Gómez, F., Cavalazzi, B., Rocchini, D., Altieri, F., and De Sanctis, M. C.: Remote Sensing Observations of Sulfides and Sulfates for the Geologic Mapping of the Extreme Acidic Environment of Rio Tinto, Spain, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-506, https://doi.org/10.5194/egusphere-egu24-506, 2024.

Geological map is mainly a result of the subjective interpretation of geological data collected as point (e.g. boreholes) and linear data (e.g. geophysical surveys), followed by their interpolation and extrapolation to areas where there is no data available. Currently, Geographic Information Systems (GIS) systems replace traditional cartographic methods that were widely used in the geosciences in the past. The unambiguous interpretation of analogue/paper geological maps is often a challenge, especially in those cases where the uncertainties and their extent were represented using artistic methods such as shading, hatching or using different symbols. 

In the past, the digitisation of geological maps involved the use of GIS software only as a graphical tool, resulting in a map developed for a paper publication. Such map was a redrawn version of a paper map, representing exactly the same vision as the author of the analogue map had. Today, GIS tools offer many spatial data processing functions that provide new information, which was not possible in case of paper maps. GIS analysis can be used to assess the quality of collected data, allowing geological data to be harmonised.
Today, to classify a digital map, geological data have to be structured at much deeper level than before The heterogeneity of geological data and the difficulty of acquiring it results in the necessity of introducing artificial boundaries on maps, especially when it comes to geological structures covered and/or deformed by overlying structures - such as the Carpathian substrate deformed and covered by the structures of the Alpine orogeny - These boundaries separate detailed structures from those that have not been identified. Some boundaries are entirely artificial and indicate the extent of possible interpretations rather than the extent of occurrence of geological structures. Similar problems arise with Quaternary substrates, which may have been subjected to strong stresses during glaciations, resulting in glaciotectonic deformations. Despite an apparently thoroughly investigated Quaternary cover, the discovery of glaciotectonic disturbances can still be a stroke of luck.

How to cite: Stępień, U., Jóźwik, K., Słodkowski, M., and Gałązka, D.: The art of geological mapping in a precisely defined world: do only extreme environments pose a challenge for 2D geological mapping?, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3411, https://doi.org/10.5194/egusphere-egu24-3411, 2024.

Increasing anthropogenic pressure in marine and coastal environments emphasizes the importance of the easily accessible, reliable, and suitable data on marine environment, to support conservation, research, and sustainable marine management decisions. The EMODnet (European Marine Observation and Data network) Geology project has been aiming to address this demand by collecting and harmonizing geological data at different scales from all the European sea areas since 2009, at present with a collaboration of about 40 partners and subcontractors.

Multiscale Seabed substrate is one of the key data products of EMODnet Geology that has been collected since the beginning of the project. The seabed substrate map, harmonized from the national data by the sediment grain size, has evolved and complementary data products have been developed during the years. Sedimentation rates information has been collected since the beginning, and the seabed substrate database also includes information on the seabed surface characteristics that have significance for marine environment but cannot be defined by grain size only (e.g., seagrass meadows, glacial clay, moving sediments, ferromanganese concretion bottoms and bioclastic features). Similarly, the geographical scope has expanded currently including the Caspian Sea and Caribbean Sea.

Seabed dynamics, sediment accumulation and erosion, provide an indication of potential temporal seabed-sediment variability, and thus of uncertainty. To obtain this essential information, the latest addition in the seabed substrate data products is the seabed erosion index database, i.e. literature catalogue of erosion studies. The first version of the database was published in September 2023, including metadata information (e.g., purpose, time frame, erosion rate and data availability) about known erosional studies and different erosional areas. The index data collection will continue within the current phase of the EMODnet Geology, and it will serve as the basis for the discussion which kind of erosional data information could be the most valuable, but also as widely as possible feasible and useful. The development of usable and valuable data products requires the careful consideration and preferably collaboration with different stakeholders and end users. At best, this kind of data could be a valuable addition to understand and define marine environment in dealing with various challenges the future will hold us.

The EMODnet Geology project is funded by The European Climate, Environment, and Infrastructure Executive Agency (CINEA) through contract EASME/EMFF/2020/3.1.11 - Lot 2/SI2.853812_EMODnet – Geology.

How to cite: Kihlman, S., Kaskela, A., Kotilainen, A., Alanen, U., Vallius, H., and partners, E. G.: Gone with the currents? – Seabed erosion data of EMODnet Geology, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10302, https://doi.org/10.5194/egusphere-egu24-10302, 2024.

Neutron detection, as well as gamma-ray spectroscopy are powerful tools for in-situ resources utilization. They allow for characterizing the abundance of hydrogen and elemental composition of the top meter of moons, airless planets, or asteroids. Compact instruments can be deployed both on orbiters and landers/rovers for either mapping larger areas or narrowing down locations with targeted materials. A more specific application is the abundance mapping of water in the lunar polar regions. To improve the Lunar Prospector resolution maps, a satellite in a low altitude orbit, below 30km, of the lunar surface is needed. This can be accomplished by a small satellite, like a CubeSat. 

We propose a hybrid gamma-ray and neutron detector based on scintillator technology for space exploration, sensitive to gamma-rays in the spectral range of 30keV to 8MeV as well as to thermal and epithermal neutrons. The detector consists of an array of CLLBC scintillators that are read out by silicon photomultipliers attached to partially space-qualified read-out electronics provided by IDEAS. In the targeted configuration, the compact instrument will have the size of tow CubeSat units (2U), where one unit is covered in Cd to allow for the distinction between epithermal and thermal neutrons.

A good understanding of the targeted radiation environment is vital for simulating and characterizing the instrument’s performance before deployment. We performed an environmental analysis for the Moon that provides the input parameters for detector response simulation in GEANT4.  With the detector response simulation, the detector design can be optimized, and characterization measurement data from the physical instrument can be verified.

In this paper, we present the mechanism behind the detection of targeted elements, such as hydrogen, KREEP, Fe, Ti and Sm, the results from the lunar radiation environment simulation and first results from the detector response simulation. A demonstrator instrument was assembled and tested in a laboratory, the first results look promising, showing that the targeted energy range for gamma-ray and neutrons can be detected. The performance of the lab demonstrator will be presented, as well.

How to cite: Kohfeldt, A., Al Jebali, R., and Teodoro, L.: A Compact Gamma-Ray and Neutron Detector for Abundance Mapping on the Moon, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10756, https://doi.org/10.5194/egusphere-egu24-10756, 2024.

Rock outcrops protruding above the ice surface in Antarctica (nunataks) can provide direct geologic evidence for past ice sheet fluctuations through the measurement of concentrations of cosmogenic nuclides that accumulate in their surfaces once the rock is exposed. Felsic lithologies, which are typically pale in colour and dominated by quartz, feldspars, and micas, are suitable for exposure age dating since quartz is the often-preferred target mineral for extraction of the rare cosmogenic isotopes which make deglacial reconstructions possible. The geology of rock outcrops in Antarctica are, however, often sparsely mapped and many exposures are challenging to access due to both their remoteness and the extreme conditions typically encountered on the continent. Satellite based spectral mapping offers an effective way to characterise the geology of large areas of exposed rock rapidly and safely in regions where it is logistically very challenging and expensive to conduct fieldwork. Remote sensing therefore offers a valuable method for preliminary characterisation of an area’s suitability for eventual targeted retrieval of cosmogenic nuclide samples.

Previous studies found that the Thermal Infra-Red (TIR) sensor onboard the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is very effective at discriminating rock types by their silica content, but spectral mapping of smaller felsic rock outcrops in Antarctica has been constrained by its low spatial resolution (90 m). Here we assess the potential of multispectral remote sensing using both ASTER and very high-resolution Worldview-3 (WV-3) imagery to distinguish felsic from mafic rock outcrops at visible-near infrared (VNIR) and shortwave infrared (SWIR) wavelengths. At Mount Murphy, a remote site in West Antarctica more than 1,600 kilometres from both the US Antarctic Program’s McMurdo Station and the British Antarctic Survey’s Rothera Research Station, we identify four dominant rock types from our spectral mapping: granites, gneisses, basalt and fragmental hydrovolcanic rocks (hyaloclastite). Image derived spectral profiles of these four rock types were used as input for spectral classification and lithological mapping of the Mount Murphy site. Supervised classification results indicate that WV-3 performs well at differentiating felsic from mafic rock types and that ASTER imagery, while coarser in resolution, can also achieve satisfactory results, and could therefore be used in concert with more targeted WV-3 image acquisitions. We also demonstrate that separation of mafic (fragmental) hydrovolcanic and basalt rock types can be achieved at VNIR-SWIR wavelengths, a result that will be useful for future spectral mapping of volcanic rocks on other planets. We used spectral mapping and supervised classification results to produce a new geologic map of Mt Murphy. Overall, our results demonstrate the potential of spectral mapping and classification using WV-3 and ASTER datasets to identify and characterise suitable sites for future cosmogenic nuclide sampling campaigns.

How to cite: Adams, J. R., Mason, P. J., Roberts, S. J., Rood, D. H., Smellie, J. L., and Johnson, J. S.: Application of very high-resolution satellite imagery to identify silica-rich rock for future cosmogenic exposure dating in remote unvisited areas of Antarctica., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12233, https://doi.org/10.5194/egusphere-egu24-12233, 2024.

This study aims to evaluate the geothermal potential and geological features of the Seferihisar area in Turkey by integrating marine seismic data with terrestrial geological observations. Additionally, the research highlights the significance of marine geophysics in exploring the existing geothermal systems in Seferihisar. In this scope, high-resolution marine multichannel seismic reflection data, collected in Seferihisar Bay along the Tuzla Fault is correlated with onshore drilling data obtained from the same fault.

A 2D conceptual section and a 3D model were developed using the data from onshore geology, geochemistry, and geophysics to well better understanding of the geological structures related to the geothermal system in the study area. The results of geochemistry data in the geothermal wells indicated that the nutrition of the geothermal fluid is of both meteoric and sea water origin. The synthesis of onshore and offshore data facilitated the identification of the marine extension of the Tuzla Fault using a 3D model, emphasizing its influence on marine contributions and fluid dynamics within the geothermal system. Thus, revealing the continuity of Quaternary faults offshore and onshore will contribute to EMODnet Geology maps.

The integration of a multidisciplinary approach enhanced our understanding of geothermal wells. This advancement not only aids in identifying new potential wells but also provides deeper insights into the risks associated with geothermal energy production.

Keywords: Tuzla fault, geothermal energy, 3D modelling, onshore-offshore integration, marine seismic reflection,  EMODnet Geology maps

How to cite: Köktentürk, G., Çifçi, G., Gürçay, S., Okay Günaydın, S., Hasözbek, A., Güngör, T., Demirkıran, Z., and Çobanoğlu, M.: Revealing the continuity of offshore faults in the Seferihisar-İzmir (Turkey) Geothermal Area by modeling with Marine Seismic and Field Geology, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15149, https://doi.org/10.5194/egusphere-egu24-15149, 2024.

Over a hundred salt diapirs, which are fed by the Precambrian Hormuz Evaporites, extrude through anticlines of the fold and thrust belt of the Zagros Mountains in southern Iran. The sheer number of diapirs, the arid climate, and the mountainous landscape have presented a long-standing challenge for traditional geological field mapping to produce high-resolution lithological maps of prominent salt features. Such maps are crucial for comprehending the role of salt diapirism in the evolution of the landscape and exploring hydrocarbon and mineral resources within the region.

To overcome this challenge, we take advantage of the rapidly expanding satellite imagery database to explore the potential of employing satellite-based multispectral and hyperspectral remote sensing for producing lithological maps of salt diapirs in arid environments. Enhancing this analysis with mineral and rock spectroscopy, our goal is to map diverse lithologies characteristic of salt diapir cupolas and genetically associated salt glaciers at the resolution permitted by currently available satellite imagery.

To test the utility of satellite-based remote sensing to lithological mapping of salt diapir features, our study focuses on three salt diapirs — Karmostaj, Siah Taq, and Champeh — in the Zagros Mountains. We used previously established ASTER-based NIR and SWIR mineral indices (Cudahy et al., 2020; Hewson et al., 2005; Rowan & Mars, 2003; Shuai et al., 2022) to delineate the distribution of SO₄^2--, Al-OH-, Mg-OH-, and CO₃^2--bearing minerals, and of ferric and clay minerals. We also investigated potential temporal and seasonal changes in the distribution of the target minerals and the strength of the spectral signals of the mineral groups. Furthermore, we calculated mineral indices from ASTER thermal imagery suggested in previous work (Guha & Vinod Kumar, 2016; Ninomiya et al., 2005; Rockwell & Hofstra, 2008) to map quartz-, sulfate-, and carbonate-bearing rocks. To validate the accuracy and precision of the ASTER-based mineral indices, we carried out Raman and FTIR spectroscopic analysis to spectrally characterize rock and mineral samples collected from cupolas, caprocks, and country rocks of various salt diapirs in the region. We subsequently applied Spectral Information Divergence (SID) classification on multispectral ASTER and hyperspectral EnMAP optical imageries.

As we extend the mapping technique to other salt diapirs across the Zagros and Arabian Peninsula regions, our findings suggest that satellite-based remote sensing offers a cost-effective and labour-saving approach for generating high-resolution lithological maps. This method has the potential to advance our understanding of the halo-tectonic evolution of the Zagros landscape once a sufficient number of salt diapirs are mapped at the current resolution. However, we note that the accuracy of lithological mapping is influenced by the spectral and spatial resolution of the available satellite imagery. Furthermore, the strength of the spectral signal of gypsiferous outcrops exhibits distinct seasonality, weakening in warm periods and strengthening in cold seasons. In conclusion, our study demonstrates the efficiency as well as the limitations of satellite-based remote sensing in improving lithological maps of exposed salt diapirs in desert environments, providing valuable insights for geological research and resource exploration in the Zagros Mountains.

How to cite: Dusingizimana, M. W., Friedrich, A. M., Kahle, B., Rieger, S. M., Heuss-Aßbichler, S., Závada, P., and Zebari, M.: Using ASTER Multispectral and EnMAP Hyperspectral Remote Sensing for Lithological Mapping of Salt Diapirs in the Zagros Mountains, Iran, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16342, https://doi.org/10.5194/egusphere-egu24-16342, 2024.

Effective maritime spatial planning, coastal zone management, management of marine resources, environmental assessments and forecasting require comprehensive understanding of the seabed. The European Commission established the European Marine Observation and Data Network (EMODnet) in 2008 and in response to these needs. The EMODnet concept is to assemble existing but often fragmented and partly inaccessible marine information into harmonized, interoperable, and freely available data layers and data products encompassing whole marine basins. As the data layers and data products are open for use, the program is supporting any European maritime activities in promotion of sustainable use and management of the European seas.

The EMODnet Geology project is delivering integrated and harmonized geological data products that include seabed substrates, sediment accumulation rates and seabed erosion index database, seafloor geology including lithology and stratigraphy, Quaternary geology and geomorphology, coastal behaviour, geological events such as submarine landslides and earthquakes, marine mineral resources, as well as submerged landscapes of the European continental shelf at various timeframes. All data products are openly available at the EMODnet Central Portal. They are presented at a scale of 1:100,000 or finer but also coarser scales to ensure maximum areal coverage. The current EMODnet Geology project phase is executed by a consortium of 40 partners and subcontractors which core is made up by members of European geological surveys (EuroGeoSurveys) backed up by other partner organizations with valuable expertise and data.

The EMODnet concept is expanding beyond European Seas, as also the Caspian and the Caribbean Seas are included in the geographical scope of the EMODnet Geology project. During the current project phase, the focus is to ensure collection and inclusion of Caribbean Sea data to the geology data layers on the EMODnet Central portal. For this purpose, EMODnet Geology is establishing collaboration with Asociación de Servicios de Geología y Minería Iberoamericanos (ASGMI) that is active in the Caribbean Sea area. Previously selected methods have been shared with the EMODnet PArtnership for China and Europe (EMOD-PACE) project (2019-2022).

The EMODnet Geology project is funded by The European Climate, Environment, and Infrastructure Executive Agency (CINEA) through contract EASME/EMFF/2020/3.1.11 - Lot 2/SI2.853812_EMODnet – Geology.

Discover Europe’s seabed geology at: https://emodnet.ec.europa.eu/en/geology

How to cite: Kaskela, A., Vallius, H., Kihlman, S., Kotilainen, A. T., Alanen, U., and Partners, E. G.: EMODNET Geology delivers marine geological data products from Europe’s seas and beyond, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17592, https://doi.org/10.5194/egusphere-egu24-17592, 2024.

North Victoria Land (NVL), Antarctica is one of the most remote and inaccessible outposts of our planet where few outcrops are available for direct geological investigation. The long-lasting tectonic evolution of this region results in a complex architecture characterized by the presence of regionally sized, crustal scale faults whose structural characteristics (e.g. geometry, thickness, location of transfer zones and off-shore prosecution) are still debated.

In this work we present a map of the intensity of brittle deformation measured in 113 field outcrops along the Rennick-Aviator km-scale fault corridor, and quantified through the non-dimensional and scale invariant H/S parameter (H = fracture dimension and S = spacing among fractures belonging to the same azimuthal family; see Cianfarra et al. 2022). The sparse fracture measurements where then interpolated with Surfer® (Golden Software, LLC) v. 23.2.17 to analyse the spatial variability of deformation with the aim of clarifying the tectonic link between the Rennick and Aviator faults.

The thematic map is prepared by a polymodal regression by full cubic surface that was applied to the field measurements (between 70.5°-71 °S and 160-165.5°E) collected during scientific expeditions funded and logistically supported by the Italian National Antarctic Program (e.g.; PNRA16-00056_G-IDEA and PNRA18-00338_LARK projects). Measurements were normalized by a weighting factor to take into account the brittle strength variability of the analysed lithotypes (e.g., basalts-dolerites, well cemented sandstone-conglomerates, granites-migmatites, gneiss)

The comparison of our georeferenced thematic map with existing maps of satellite-derived potential fields, bed subglacial topography and off-shore bathymetry, and Antarctic geology which are available as free dataset in the web (e.g. ADMAP, BEDMAP, Quantarctica, GeoMAP dataset, among the others) allows to supply constraints for modelling ice covered tectonic structures, to better highlight the active role of the main tectonic lineaments of NVL, as well as to clarify the relationship, connection and link between onshore and offshore tectonic structures (this last topic is being investigated in the frame of the ongoing PNRA19-00051_BOOST project).

Cianfarra et al. 2022, Tectonics 41, e2021TC007124, https://doi.org/10.1029/2021TC007124

How to cite: Cianfarra, P., Bagnasco, A., Locatelli, M., Federico, L., Morelli, D., Salvini, F., and Crispini, L.: Mapping the intensity of brittle deformation through ice covered regions: a study from Antarctica (North Victoria Land), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17849, https://doi.org/10.5194/egusphere-egu24-17849, 2024.

We present Bedmap3, the latest suite of gridded products describing the surface elevation, ice-thickness and the seafloor and subglacial bed elevation of Antarctica south of 60°S. Bedmap3 incorporates and adds to all post-1950s datasets previously used for Bedmap1 and Bedmap2, including 84 new aerogeophysical surveys by 15 data providers, that represent an additional 52 million data points and 1.9 million line-kilometres of measurement. These latest data have filled major gaps particularly in East Antarctica, including the South Pole and Pensacola basin, Dronning Maud Land, Recovery Glacier and Dome Fuji, Princess Elizabeth Land, plus the Antarctic Peninsula, West Antarctic coastlines, and the Transantarctic Mountains. Our newly defined Bedmap3/RINGS grounding line product similarly consolidates multiple recent mappings of this spatially varying boundary into a single, spatially coherent feature. Using these new datasets plus updated rock-outcrop mappings, we have improved our interpolation of grounded ice thickness particularly in representing linear troughs under the ice sheet and in mountain ranges such that, in many parts of Antarctica, the subglacial landscape is visible in much greater detail than was previously available. Combined with updated surface topography, ice shelf thickness and bathymetry data, these products provide new opportunities for interpreting continental-scale landscape evolution, and detailed modelling of the past and future evolution of the Antarctic ice sheets.

How to cite: Pritchard, H., Fretwell, P., Fremand, A., and Moholdt, G.: Bedmap3: improved ice bed, surface and thickness datasets for Antarctica, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17877, https://doi.org/10.5194/egusphere-egu24-17877, 2024.

The project of the International Quaternary Map of Europe project (IQUAME 2500) is a major international initiative coordinated by BGR under the auspices of the CGMW (Commission of the Geological Map of the Word, Sub-Commission Europe) and with support of INQUA.
The project is collecting  and compiling information from more than 40 partner institutions on numerous aspects of the European Quaternary. This includes the lithology and geochronological age of Quaternary units, genetic descriptions of the units, maximum extent of the ice sheets, extent of Arctic sea ice, off-shore Quaternary information,, directions of ice movement, postglacial rebound, active faults, extent of permafrost and key localities (e.g. geologically and anthropologically interesting sites),
The IQUAME is based on hundreds of past mapping campaigns all over Europe. A considerable amount took place in extreme environments such as in polar, mountainous and/or glaciated regions. For example, the mapping of Lateglacial moraines in the Eastern Alps in Austria indicating extensive multiple glacier advances after the breakdown of the Last Glacial Maximum ice cap that occur in a high alpine environment with peaks of 3000 m altitude and steep slopes. The IQUAME also presents offshore map information, as the geology does not end on the shoreline. These data are based on  data of  European Marine Observation and Data Network (EMODnet) Geology project, established in 2009 by the European Commission. Within EMODnet Geology the Workpackage “Seafloor geology” compiles and harmonizes offshore geological map layers  also from the Quaternary, from the EMODnet partners all over Europe.
Participation of the numerous international partners and the many different topics requires considerable data harmonization (semantics, structure and geometry). To achieve this, common standards and guidelines were set up and are used by all participants:  structured vocabularies to describe the IQUAME's contents, a common topographic base, technical procedures to include the map data and guidelines to aid the partners to submit their data to the project. The harmonization is still in progress.
This contribution shows the pathway from regional mapping campaigns such as the one from the Lateglacial moraines in high alpine valleys and cirques to an overall harmonized Quaternary map layer of the entire Europe.

How to cite: Asch, K. and Reitner, J. M.: The International Quaternary Map of Europe and Adjacent Areas: Results from mapping of extreme environments inclusive, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19240, https://doi.org/10.5194/egusphere-egu24-19240, 2024.

The Iceland-Faroe Ridge (IFR) is an elevated area between Iceland, the Faroe Islands, and the Hatton Bank with water depths from 300–1800 m. It is believed that the Iceland hotspot is responsible for the formation of the IFR. During the opening of the Northeast Atlantic, the Reykjanes mid-ocean ridge formed by interlinking with the Iceland hotspot. These processes created a complex wide volcanic breakup margin of volcanic rift zones or intraplate volcanism that brought magma to the surface. These processes resulted in the formation of morphologic features, as seen onshore in Iceland today, such as ridges, volcanic cones and lava flows that are a physical record of the plates being rifted and spread apart. Therefore, the IFR has been in development since the opening of the NE-Atlantic (<55 Ma), standing out as a prominent feature on bathymetric and geophysical datasets. Volcanic features such as craters, eruptive fissures, submerge lava boarders and volcanic ridges have been identified on the ridge in recent multibeam and sub-bottom profiler data from the southern part of the Iceland-Faroe Ridge acquired by Marine and Freshwater Research Institute (Iceland) and SHOM (France). With northeast-southwest trending structures, the most preserved features lies at around 1500-2000 m water depth in the southern slopes of the Iceland-Faroe Ridge. There are also evidences of volcanism in shallower depths of the IFR, however, these features are not as well preserved and have been affected by subaerial erosions and glacier erosional processes during the last ice age. These volcanic features are thought to be part of former rift axes that was probably active 30-55 Ma years ago compared to the age correlations of the surrounding oceanic floor. In the deeper part these ridge volcanic cone or ridge features are well preserved and only partly buried in sediments. They are not age dated but appear to be younger in formation time than the surrounding oceanic floor (30-55 Ma), where volcanic ridges appear to break through the sediments and older crust with evidence of sill intrusions seen on sub-bottom profiler seismic reflection data. This may Indicate a younger volcanic activity and possible still active intraplate volcanic zones that only can be confirmed by sampling, age and petrophysical analysis.

How to cite: Erlendsson, Ö., Blischke, A., Óðinsson, D. Þ., and Thordarson, S.: Evidence of volcanism and former rift axis within the southern extent of the Iceland-Faroe Ridge, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20264, https://doi.org/10.5194/egusphere-egu24-20264, 2024.