The production of geothermal energy requires the circulation of large volumes of thermal brines reaching up to several 100 L/s. These brines are the product of long-time water-rock interactions at a high temperature and depth leading to various water compositions. The contained ions have been used for the chemical characterization of a reservoir and are further a challenge for the power plant operator due to the possibility of uncontrolled mineral formation. The chemical analysis of the waters and the related precipitates have shown that the waters can contain critical and strategic mineral commodities at various concentrations. According to known standards of raw material extraction, these are not classic deposits due to their low concentrations. However, in consideration of the high annual volumes circulating in geothermal systems, relevant amounts of different raw materials are in theory extractable. An advantage of the geothermal brines is that the elements of interest are already dissolved in the water and do not have to be extracted from the rock first. Furthermore, a geothermal power plant provides decentralized heat and energy for further refinement of the raw materials. The implementation of a cost-effective and deployable mineral recovery in the geothermal cycle can thus improve the economics of geothermal energy and open up a new raw material market.

Over the past years the interest in geochemical reactions forming or oxidizing molecular hydrogen has soared: In addition to the long-standing issue of possible hydrogen production in high-level nuclear waste repositories due to corrosion of canisters or radiolysis of water, the energy transition considering molecular hydrogen as energy carrier calls for a thorough understanding of possible reactions during subsurface storage of hydrogen. Recent findings of unusually hydrogen-rich soil gases have underlined the importance of elucidating the natural hydrogen cycle before advancing the large-scale usage of hydrogen as energy carrier. This session will combine contributions investigating the reactions, processes and kinetics of formation or oxidation of hydrogen e.g. on mineral surfaces or by microorganisms – from both experimentalists and modelers to foster the exchange. Additionally, it will integrate research on controls of hydrogen migration – as loss from subsurface storage, possible pressure-release mechanism during the long-term storage of high-level nuclear waste or in the context of natural hydrogen fluxes in marine (e.g. hydrothermal) and continental settings, prerequisite for possible accumulations of hydrogen in the geosphere.

The composition of clastic sediments or sedimentary rocks is a result of source area properties, sediment generation and transport processes as well as post-depositional changes. Deciphering the provenance of clastic deposits can therefore provide valuable insights into tectonic, geomorphic, climatic and anthropogenic factors and processes shaping sedimentary systems over different temporal and spatial scales. This session welcomes contributions that investigate (1) the provenance of clastic deposits by analyzing compositional (e.g. mineralogical, geochemical) properties, (2) the processes that modify detrital signals throughout the sedimentary routing system, and (3) the relationships to internal and external forcing mechanisms.

This session thematizes the formation, evolution and economic importance of carbonatites and alkaline rocks. These play an important role for our society, as they contain exceptional high levels of critical raw materials, such as REE, Nb, P and F, to name a few. However, to understand how such deposits form, we need to understand how their rocks and mineral assemblages formed in space and time.Although our knowledge about the formation and mineralization as well as the magmatic and post-magmatic modification of carbonatites and alkaline rocks strongly improved over the last decades and the extraction of related raw materials could be steadily refined, there are still many open questions that need to be addressed. We encourage participants to submit and present their studies relating to carbonatites and alkaline rocks in this sub-session and to discuss and network their research. The scope of this session covers the formation, the ascent and the emplacement, but also the mineralization, differentiation and alteration of these unique rocks as well as their exploration, exploitation and processing. Experiments and numerical calculations are as welcome as field work studies and analytical investigations.

The issue of seismicity induced by human activities, e.g. through fluid injection (waste water disposal, hydraulic fracturing), has become increasingly important with technology upscaling. In some regions of the world, seismicity associated with the exploitation of hydrocarbons exceeds natural earthquake activity. Monitoring of induced seismicity with local networks is a key element for managing induced seismicity risks. At the same time there is an increasing number of wind turbines and the associated increase of ground vibrations. This combination complicates ground motion analyses and can disturb earthquake monitoring. A lot of research is ongoing in these topics and we want to provide a platform for exchanging latest results and ideas. Therefore, we invite contributions from research on induced seismicity and/or technically induced seismic signals covering theory, observations and experimental aspects. 

In Deutschland soll Wasserstoff mit Hilfe von erneuerbaren Energien gewonnen und als Energieträger im Verkehrssektor und als Rohstoff in der Industrie verwendet werden. Die deutsche Wasserstoffstrategie geht davon aus, dass übergangsweise auch CO2-neutraler Wasserstoff aus der Methan-Pyrolyse und aus Erdgas mit CO2-Speicherung genutzt wird. Die bis 2030 in Deutschland geplanten Elektrolyseure mit einer Kapazität von 5 GW werden etwa 14% der erwarteten Nachfrage liefern.Wie kann der Bedarf an preisgünstigem Wasserstoff gedeckt und die sichere Zwischenspeicherung in großen Untertagespeichern und dezentral bei Großverbrauchern gewährleistet werden? Ist ein zusätzlicher Wettbewerb um Rohstoffe für den Bau von Elektrolyseuren und Erneuerbare-Energieanlagen zur Herstellung von Wasserstoff zu erwarten, wenn gleichzeitig auch andere Industrieländer eine Wasserstoffwirtschaft entwickeln? Sind Innovationen abzusehen, die Wasserstoff im Verkehrssektor und als Rohstoff der Industrie wettbewerbsfähig machen?

Diskussionsteilnehmer:

• Prof. Dr. Holger Hanselka, President of the KIT and Vice-President Research Field Energy, Helmholtz Association, 76131 Karlsruhe, Germany

• Dr. Klaus Langemann, WintershallDEA GmbH, Senior Vice-President Carbon Management & Hydrogen, Friedrich-Ebert-Straße 160, 34119 Kassel, Germany

• Dr. Markus Oles, ThyssenKrupp Steel Europe AG, Head of Carbon2Chem, Sustainable Production, 47166 Duisburg, Germany

• Hans-Joachim Polk, VNG AG, Member of the Executive Board, Infrastructure & Technical Affairs, Braunstraße 7, 04347 Leipzig, Germany

• Michael Schmidt, Deutsche Rohstoffagentur (DERA) in der Bundesanstalt für Geowissenschaften und Rohstoffe (BGR), Wilhelmstraße 25-30, 13593 Berlin-Spandau, Germany

With the urgent need to quickly reduce CO2 emissions, deep geothermal energy can provide an indispensable contribution in the future energy mix. To encourage future projects, it is essential to significantly decrease the exploration risks of geothermal projects. This reduction should encourage investments, increase the probability of success and decrease surface impact to communities. Ranging from direct exploration risks to surface implications for communities, this session is directed to uncertainty quantification and risk reduction e.g. geological modelling, novel exploration as well as reservoir testing and monitoring techniques. Armed with this knowledge, better decisions can be made for project developments, like selection of drilling targets, reservoir operations or mitigations efforts. We invite contributions on geological, geophysical and reservoir engineering aspects of uncertainty quantification and risk reduction within Geothermal energy.

The interaction of fluid and rock, and the properties of pores and their connectivity are among the main controls on the production and storage potential in clastic and carbonate rocks. At least as much as in the hydrocarbon sector, the exploration of geothermal resources or storage sites for CO2 or hydrogen, require knowledge of processes on the pore scale. Compaction, cementation, dissolution, and alteration, control the evolution of reservoir quality and are also key to understanding the risk of formation damage. All may occur on geological time scales or happen rather quickly during production or storage as the composition and/or pressure of the pore fluids is changed dramatically within a short period of time. The process-based understanding of diagenesis controlling reservoir behavior will aid in future utilization of the subsurface in outlining possibilities for better assessment, prediction chances and risks of classic and renewable energy. Numerical simulations are the only way to connect micro-scale processes, which may significantly alter the internal rock structure, with the macro-scale, which consequently affect the hydraulic behaviour of the system.This session aims to showcase recent developments in reservoir petrography, petrographic modelling, and prediction utilizing multiple geological, geochemical, and geophysical methods and approaches like reactive transport modelling. We invite submissions presenting e.g., case studies, integrations of novel methodologies, and new interpretations of legacy data for future energy challenges. 

The composition of clastic sediments or sedimentary rocks is a result of source area properties, sediment generation and transport processes as well as post-depositional changes. Deciphering the provenance of clastic deposits can therefore provide valuable insights into tectonic, geomorphic, climatic and anthropogenic factors and processes shaping sedimentary systems over different temporal and spatial scales. This session welcomes contributions that investigate (1) the provenance of clastic deposits by analyzing compositional (e.g. mineralogical, geochemical) properties, (2) the processes that modify detrital signals throughout the sedimentary routing system, and (3) the relationships to internal and external forcing mechanisms.

This session thematizes the formation, evolution and economic importance of carbonatites and alkaline rocks. These play an important role for our society, as they contain exceptional high levels of critical raw materials, such as REE, Nb, P and F, to name a few. However, to understand how such deposits form, we need to understand how their rocks and mineral assemblages formed in space and time.Although our knowledge about the formation and mineralization as well as the magmatic and post-magmatic modification of carbonatites and alkaline rocks strongly improved over the last decades and the extraction of related raw materials could be steadily refined, there are still many open questions that need to be addressed. We encourage participants to submit and present their studies relating to carbonatites and alkaline rocks in this sub-session and to discuss and network their research. The scope of this session covers the formation, the ascent and the emplacement, but also the mineralization, differentiation and alteration of these unique rocks as well as their exploration, exploitation and processing. Experiments and numerical calculations are as welcome as field work studies and analytical investigations.

Gravity measurements contain important information about the subsurface at every spatial scale. Satellite missions provide highly accurate, global measurements, that allow building and testing 3D models of the Earth even for regions where other geophysical measurements are sparse. Depending on the envisaged model resolution and application, gravity data from regional or local surveys (e.g. ship and airborne) can be incorporated to provide higher resolution. However, solutions to the gravity inverse problem are non-unique and constraints by independent geological and geophysical observations need to be integrated to develop reliable subsurface density models. Such models, in turn, provide insights into subsurface variations in composition and thermo-mechanical state.In this session, we welcome contributions that integrate gravity and/or gradient data (at all scales) with other geophysical measurements and geological information to better understand the structure, properties and processes of the Earth’s subsurface. Hence, we would like to discuss diverse applications, from global scale, where mantle properties are assessed, down to the reservoir scale. We also welcome more technical contributions that address related topics like innovative joint inversion methods, model uncertainty estimation and determinations of parameter sensitivities, as well as temporal variations of the gravity field, and new interpretation software and techniques.

The interaction of fluid and rock, and the properties of pores and their connectivity are among the main controls on the production and storage potential in clastic and carbonate rocks. At least as much as in the hydrocarbon sector, the exploration of geothermal resources or storage sites for CO2 or hydrogen, require knowledge of processes on the pore scale. Compaction, cementation, dissolution, and alteration, control the evolution of reservoir quality and are also key to understanding the risk of formation damage. All may occur on geological time scales or happen rather quickly during production or storage as the composition and/or pressure of the pore fluids is changed dramatically within a short period of time. The process-based understanding of diagenesis controlling reservoir behavior will aid in future utilization of the subsurface in outlining possibilities for better assessment, prediction chances and risks of classic and renewable energy. Numerical simulations are the only way to connect micro-scale processes, which may significantly alter the internal rock structure, with the macro-scale, which consequently affect the hydraulic behaviour of the system.This session aims to showcase recent developments in reservoir petrography, petrographic modelling, and prediction utilizing multiple geological, geochemical, and geophysical methods and approaches like reactive transport modelling. We invite submissions presenting e.g., case studies, integrations of novel methodologies, and new interpretations of legacy data for future energy challenges. 

This session addresses the dynamics of sedimentary basins at different temporal and spatial scales and aims to bring together a wide range of studies focusing on geodynamics, tectonics and sediment dynamics. Contributions addressing major processes affecting the genesis and evolution of basins are in particular encouraged (from rifting and overlying passive continental margins to orogenic, intra-montane and extensional back-arcs in convergent settings). A wide range of studies are encouraged, aimed at understanding the evolution of sedimentary fill, the underlying crustal and lithospheric -scale dynamics as well as the integration with processes taking place in the source areas, such as active orogens or long-term landscape evolution. We welcome contributions integrating data from different depth levels of the lithosphere with the shallower parts of the basin system as subsidence pattern, stress, vertical motions, erosion and sedimentation dynamics, thermal structure, lithosphere dynamics and (active) faulting by the means of observational studies, numerical and analogue modeling, or their combination. Studies yielding constraints on a variety of conceptual and quantitative models explaining the origin and evolution of basins are also welcomed.Session sponsored by the International Lithosphere Program Task Force VI Sedimentary Basins 

The Earth’s crust and related mineral resources were formed and modified by magmatic and metamorphic process through Earth’s history. Understanding of these processes in space and time is therefore of fundamental interest for Geoscientist and Society. This session deals with all aspects of magmatic and metamorphic rocks formed through Earth’s history from global to nanoscale. Presentations are welcome dealing with (i) experimental petrology, (ii) field-based studies on magmatic and metamorphic rocks and processes in all kind of geological settings, from crust to mantle and back, (iii) thermodynamic and kinetic modelling, and (iv) related geochronological aspects.

Gravity measurements contain important information about the subsurface at every spatial scale. Satellite missions provide highly accurate, global measurements, that allow building and testing 3D models of the Earth even for regions where other geophysical measurements are sparse. Depending on the envisaged model resolution and application, gravity data from regional or local surveys (e.g. ship and airborne) can be incorporated to provide higher resolution. However, solutions to the gravity inverse problem are non-unique and constraints by independent geological and geophysical observations need to be integrated to develop reliable subsurface density models. Such models, in turn, provide insights into subsurface variations in composition and thermo-mechanical state.In this session, we welcome contributions that integrate gravity and/or gradient data (at all scales) with other geophysical measurements and geological information to better understand the structure, properties and processes of the Earth’s subsurface. Hence, we would like to discuss diverse applications, from global scale, where mantle properties are assessed, down to the reservoir scale. We also welcome more technical contributions that address related topics like innovative joint inversion methods, model uncertainty estimation and determinations of parameter sensitivities, as well as temporal variations of the gravity field, and new interpretation software and techniques.

This session will showcase geological field trips to some of the most spectacular outcrops around the world. Virtual Outcrops provide an opportunity to a larger audience to visualize and learn about outcrops that expose a certain geological characteristic (architecture/structure/facies heterogeneity amongst a few), and have academic / industry relevance.In reservoir studies, outcrop analogues provide important insights into the vertical and lateral heterogeneity of reservoir properties, which in turn affect hydrocarbon recovery and cost-effective reservoir development. The advent of high resolution drone and satellite based remote sensing techniques has opened a window to illuminate a blind spot in reservoir studies that existed between low resolution 3D seismic data and high resolution 2D data from wells.The datasets included in the field trips would be (but not limited to) standard sedimentological, but also geological and petrophysical data. The presenters are allowed to use any 3D platforms which caters to their needs to carry out a 3D virtual field trip. 

Intended Audience: This session will present current research as well as tools and applications that are intended to be of interest to both academic and industry audience. Audience will be exposed to most current tools and applications being utilized to not only work but also display 3D outcrop models.