Carbon dioxide removal (CDR) technologies are vital for mitigating climate change by reducing atmospheric CO₂ levels. Geophysical methods play a crucial role in enhancing the efficiency and safety of these technologies, particularly in subsurface carbon sequestration and storage. This talk will explore innovative geophysical approaches and emerging technologies that aid in the characterization, verification, and long-term monitoring of various CDR technologies and carbon storage sites. I will discuss how geophysical techniques—such as seismic reflection, electrical resistivity, and electromagnetic methods—can be integrated to assess the suitability of geological formations for CO₂ storage. Case studies that demonstrate the application of these methods as well as the use of advanced modeling and inversion techniques in monitoring CO₂ injection and migration, ensuring the integrity of storage sites will be discussed. The seminar will also open the discussion on future directions in geophysical research, emphasizing the development of new methods and the integration of multidisciplinary data to advance CDR technologies.

Austria is committed to becoming climate net-neutral by 2040, no later than 2050. Reducing the countries hard-to-abate CO₂ emissions will require the substantial application of CCS to reach this challenging goal. Due to legal regulation and missing public acceptance across Europe, storage sites for CCS hubs are typically being developed offshore. This is especially challenging for landlocked countries like Austria where domestic storage is currently not developed and export of CO₂ can only take off once transport infrastructure is completed. The talk will shortly discuss the development of legal regulations concerning CCS in Austria and touch upon possible export routes to offshore storage sites. Afterwards new results on storage potential in hydrocarbon fields are presented and compared to already existing studies. Storage of pure hydrogen in porous media is an emerging technology that is hoped to be used for balancing fluctuations in renewable energy and decarbonizing heavy industry. At the same time geothermal energy production is seen as a key technology in providing green base-load energy for decarbonization of the heating sector in cities with district heating networks. The competitive usage of the Austrian subsurface as well the possible contribution of CCS to Austria's climate goals are finally being discussed.

Seal rocks are traditionally considered essential elements of a working petroleum system. More recently they attracted broad attention in the context of various emerging geoenergy applications, such as underground hydrogen storage (UHS) and carbon capture and storage (CCS).

This talk focuses on fine-grained siliciclastic seal rocks. A workflow for compaction analysis based on extensive core and wireline log data from the Vienna Basin is presented. The petrophysical trends are then compared to established mathematical compaction models and the validity of a generalized basin-wide “normal compaction trend” (NCT) model is discussed. Furthermore, the static seal capacity is evaluated based on capillary pressure data, and maximum seal capacity vs. depth trends are derived. Finally, dynamic leakage calculations considering different transport processes (Darcy flow, Knudsen diffusion, etc.) are introduced and implications for long-term underground storage safety are discussed.

Since rock-fluid interactions may alter the pore structure and fluid transport properties of a capillary seal, the results of gas exposure trials on the Hall Formation caprock of the first successful UHS facility in the Lehen Field (North Alpine Foreland Basin) are presented. The talk will conclude with an outlook on future activities of the Energy Geosciences team at Montanuniversitaet Leoben in the field of geo-storage seal integrity.

David Misch holds a doctoral degree from Montanuniversitaet Leoben, where he also obtained his habilitation in Geology. He worked as an invited postdoctoral researcher at RWTH Aachen University and was awarded the Walther E. Petraschek and Hans Höfer von Heimhalt prizes of the ÖAW and ÖGG, respectively, for his early career research in sedimentology. He was appointed Professor of Energy Geosciences at Montanuniversitaet Leoben in 2023 and currently heads the Chair of Energy Geosciences as well as the Department of Applied Geosciences and Geophysics.

The Earth contains many geological faults where rocks have slipped past one another during deformation of the crust. Slip on these faults would have caused earthquakes in the geological past. These faults remain as weaknesses in the crust to the present day and they can slip, causing earthquakes again, if the stresses acting on them change. Changes in stresses on faults can result from many human activities, including water injection into the subsurface for geothermal energy. Current methods for predicting the likelihood of inducing slip on faults assume that faults are planar surfaces, but observations of natural faults show that they have uneven surfaces and are usually corrugated. Here we conduct a mechanical analysis of slip on an uneven fault surface, idealised as a surface with a saw-tooth profile. The analysis calculates the amount by which fault corrugation increases the slip resistance of a fault with maximum increase perpendicular to the corrugations. It also demonstrates that fault surface corrugation can significantly deflect the fault slip direction. Our results can be applied to better predict artificially induced earthquakes on faults in the subsurface.

Sunlight is an essentially inexhaustible natural source of energy, and harvesting solar energy is of pivotal importance for the necessary energy transition. Solar irradiation depends, however, on latitude and is subject to daily and seasonal variations. For constant energy supply, the energy harvested from sunlight needs to be converted to chemical fuel that can be stored, transported, distributed and used on demand.

Conversion of solar energy to hydrogen by solar driven water splitting is an interesting route, as hydrogen has high energy density and merely produces water upon utilization. Solar energy to hydrogen conversion may be done by electrolysis of water powered by photovoltaics, by photoelectrochemical water splitting, which uses semiconducting metal oxides as light absorber and catalyst, and by solar thermal water splitting, a cyclic high-temperature process driven by concentrated sunlight.

In solar thermal water splitting, use is made of the fact that upon heating to high temperatures, transition metal oxides liberate oxygen implying reduction of their constituent transition metal cations. At lower temperatures, the oxides tend to re-attract oxygen, with the capacity to split H₂O leaving behind H₂ and the re-oxidized transition metal oxide. In this presentation different material systems used for solar thermal water splitting are discussed with a focus on hercynite-magnetite solid solutions and with an outlook on how geo-materials research can contribute to further developing this technique.

Rainer Abart is Professor for Theoretical and Experimental Petrology. He did his undergrad studies in Geology at the University of Vienna, completed his PhD in Petrology at ETH Zurich and his Habilitation at University of Graz. He held academic positions in Zurich, Graz, Basel and Berlin. In 2009 he joined the Department of Lithospheric Research, University of Vienna and since then has worked on the thermodynamics and kinetics as well as on microstructure and texture evolution in mineral systems with applications to rocks and synthetic analogues.