Conference Abstract
| 
06 Sep 2023
Conference Abstract |
| 06 Sep 2023
| 06 Sep 2023
Time to change the geoscientific perspective!?
Michael Kühn
CORRESPONDING AUTHOR
GFZ German Research Centre for Geosciences, 14473 Potsdam, Germany
Dirk Bosbach
Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
Horst Geckeis
Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen,
Germany
Vinzenz Brendler
Helmholtz-Zentrum Dresden-Rossendorf e.V., 01328 Dresden, Germany
Olaf Kolditz
Helmholtz-Zentrum für Umweltforschung GmbH – UFZ, 04318 Leipzig, Germany
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Waiwera is a small coastal village located on New Zealand's North Island above a geothermal reservoir. The origin of the warm water is not well understood. An inferred fault zone at the base of the reservoir is thought to channelise the uprising thermal water. The observed characteristic cold and hot water distribution in the system was simulated and the temperature profiles show an improved agreement in the near field around the centre of the reservoir.
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Uranium migration for a close to real case situation is quantified with reactive transport simulations using input data from the deep geothermal borehole Schlattingen, which is near the targeted area in Switzerland, and including the effect of the multi-barrier system on the source term. The hydrogeological system must always be considered in safety assessments since adjacent aquifers have a major impact on the pore water geochemistry, and hence sorption processes.
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Migration of uranium in the potential host rock Opalinus Clay is used as an example to demonstrate the extent to which simulated migration lengths can vary for a million years, depending on the model concept and on the underlying data and parameters. To reduce the uncertainty in this context, the calcite carbonate ion and the hydrogeological system at a potential disposal site need to be known, whereas the quantity of clay minerals plays a subordinate role, as long as it is enough.
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The present study, uses density-driven flow and transport models to evaluate mechanisms of saline water intrusion from deep aquifers into the freshwater column used for drinking water supply under different boundary conditions and for a specific site in the German Federal State of Brandenburg. Results show that mainly decreasing groundwater recharge leads to increased and earlier salinisation which highlights the need for waterworks to initiate effective countermeasures quickly and in time.
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Uranium migration in the Swiss Opalinus Clay is used as an example to quantify the influence of varying values of a stability constant in the underlying thermodynamic database within the law of mass action on the migration lengths. The difference of the stability constant of 1.33 log units lead to changed migration lengths of 5 m to 7 m. With a maximum diffusion distance of 22 m the influence of an uncertain stability constant is negligible for the host rock scale.
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Sonja Martens, Christopher Juhlin, Viktor J. Bruckman, Gregor Giebel, Thomas Nagel, Antonio P. Rinaldi, and Michael Kühn
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Michael Kühn and Tim Schöne
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The water level of the Waiwera geothermal reservoir increased in the hours and days after the Kaikoura earthquake on 14 November 2016. We determined in a continuous time series consisting of monthly means of water level data and pumping rates starting in 1986 if events above a certain strength alter groundwater dynamics at Waiwera. A clear correlation cannot be proven but none of the recorded earthquakes led to such a high energy density in Waiwera as the Kaikoura event did.
Sonja Martens, Christopher Juhlin, Viktor J. Bruckman, Kristen Mitchell, Luke Griffiths, and Michael Kühn
Adv. Geosci., 45, 163–166, https://doi.org/10.5194/adgeo-45-163-2018, https://doi.org/10.5194/adgeo-45-163-2018, 2018
Elena Tillner, Maria Langer, Thomas Kempka, and Michael Kühn
Hydrol. Earth Syst. Sci., 20, 1049–1067, https://doi.org/10.5194/hess-20-1049-2016, https://doi.org/10.5194/hess-20-1049-2016, 2016
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The degree of shallow aquifer salinisation triggered by fluid injection into deeper brine-bearing aquifers and brine upward migration through hydraulically conductive faults strongly depends on the regional depth of the freshwater-saltwater boundary, since displaced brines originate only from the upper fault damage zones in the study area. The highest local salinity increase in shallow aquifers occurs in case of closed model boundaries and low fault damage zone volumes.
M. De Lucia, T. Kempka, and M. Kühn
Geosci. Model Dev., 8, 279–294, https://doi.org/10.5194/gmd-8-279-2015, https://doi.org/10.5194/gmd-8-279-2015, 2015
Michael Kühn, Vaughan Stagpoole, Graham Paul D. Viskovic, and Thomas Kempka
Adv. Geosci., 65, 1–7, https://doi.org/10.5194/adgeo-65-1-2024, https://doi.org/10.5194/adgeo-65-1-2024, 2024
Short summary
Short summary
Waiwera is a small coastal village located on New Zealand's North Island above a geothermal reservoir. The origin of the warm water is not well understood. An inferred fault zone at the base of the reservoir is thought to channelise the uprising thermal water. The observed characteristic cold and hot water distribution in the system was simulated and the temperature profiles show an improved agreement in the near field around the centre of the reservoir.
Olaf Kolditz, Christopher McDermott, Jeoung Seok Yoon, Jörg Renner, Li Zhuang, Andrew Fraser-Harris, Michael Chandler, Samuel Graham, Ju Wang, and Mostafa Mollaali
Saf. Nucl. Waste Disposal Discuss., https://doi.org/10.5194/sand-2024-2, https://doi.org/10.5194/sand-2024-2, 2024
Preprint under review for SaND
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The DECOVALEX Task SAFENET is dedicated to advancing the understanding of fracture nucleation and evolution processes in crystalline rocks, with applications in nuclear waste management and geothermal reservoir engineering.
Vinzenz Brendler and Solveig Pospiech
Saf. Nucl. Waste Disposal Discuss., https://doi.org/10.5194/sand-2024-1, https://doi.org/10.5194/sand-2024-1, 2024
Revised manuscript under review for SaND
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Decisions associated with radioactive waste management are made in the presence of irreducible and reducible uncertainties. Here, the identification of such uncertainties (namely numerical ones), their ranking according to relevance, their categorization, the elucidation of internal dependencies and cross-interactions is addressed. Suitable methodologies to analyse and illustrate complex uncertainty patterns are discussed.
Michael Kühn, Viktor J. Bruckman, Sonja Martens, Johannes Miocic, and Giorgia Stasi
Adv. Geosci., 62, 67–69, https://doi.org/10.5194/adgeo-62-67-2024, https://doi.org/10.5194/adgeo-62-67-2024, 2024
Theresa Hennig and Michael Kühn
Adv. Geosci., 62, 21–30, https://doi.org/10.5194/adgeo-62-21-2023, https://doi.org/10.5194/adgeo-62-21-2023, 2023
Short summary
Short summary
Uranium migration for a close to real case situation is quantified with reactive transport simulations using input data from the deep geothermal borehole Schlattingen, which is near the targeted area in Switzerland, and including the effect of the multi-barrier system on the source term. The hydrogeological system must always be considered in safety assessments since adjacent aquifers have a major impact on the pore water geochemistry, and hence sorption processes.
Theresa Hennig and Michael Kühn
Saf. Nucl. Waste Disposal, 2, 147–147, https://doi.org/10.5194/sand-2-147-2023, https://doi.org/10.5194/sand-2-147-2023, 2023
Short summary
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Migration of uranium in the potential host rock Opalinus Clay is used as an example to demonstrate the extent to which simulated migration lengths can vary for a million years, depending on the model concept and on the underlying data and parameters. To reduce the uncertainty in this context, the calcite carbonate ion and the hydrogeological system at a potential disposal site need to be known, whereas the quantity of clay minerals plays a subordinate role, as long as it is enough.
Helge C. Moog, Tina Scharge, Holger Seher, Frank Bok, Vinzenz Brendler, Anke Richter, Laurin Wissmeier, Mareike Henneberg, Marcus Altmaier, Xavier Gaona, Nese Cevirim-Papaioannou, Daniela Freyer, Melanie Pannach, Julia Sohr, and Wolfgang Voigt
Saf. Nucl. Waste Disposal, 2, 157–157, https://doi.org/10.5194/sand-2-157-2023, https://doi.org/10.5194/sand-2-157-2023, 2023
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Crystalline rocks are being considered as potential host rocks in the ongoing search for a suitable site for a nuclear waste repository in Germany, where there is no existing experience in terms of excavating a repository in crystalline rocks. The planned underground laboratory GeoLaB addressing crystalline geothermal reservoirs offers unique opportunities for synergies with nuclear waste disposal research and development, especially in the exploration and building phases.
Natalia Mayordomo, Diana M. Rodríguez, Vinzenz Brendler, André Rossberg, Andreas C. Scheinost, Dieter Schild, Irene Cardaio, Arkadz Bureika, Caroline Börner, and Katharina Müller
Saf. Nucl. Waste Disposal, 2, 155–156, https://doi.org/10.5194/sand-2-155-2023, https://doi.org/10.5194/sand-2-155-2023, 2023
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In the last few years, we have studied the immobilization of the long-lived fission product technetium-99 (99Tc) by various Fe(II) minerals. Those minerals enable the reduction of Tc(VII) to Tc(IV), which is crucial to decrease the migration of technetium in the environment. In the future, we want to analyze Tc immobilization strategies under more complex systems that could, in a more realistic way, improve environmental conditions.
René Kahnt, Heinz Konietzky, Thomas Nagel, Olaf Kolditz, Andreas Jockel, Christian B. Silbermann, Friederike Tiedtke, Tobias Meisel, Florian Zill, Anton Carl, Aron D. Gabriel, and Marcel Schlegel
Saf. Nucl. Waste Disposal, 2, 117–118, https://doi.org/10.5194/sand-2-117-2023, https://doi.org/10.5194/sand-2-117-2023, 2023
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Jessica Lessing, Julia Neumann, Frank Bok, Johannes Lützenkirchen, Vinzenz Brendler, Moritz Schmidt, and Thorsten Stumpf
Saf. Nucl. Waste Disposal, 2, 161–162, https://doi.org/10.5194/sand-2-161-2023, https://doi.org/10.5194/sand-2-161-2023, 2023
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Jenna Poonoosamy, Mara I. Lönartz, Yuankai Yang, Guido Deissmann, Georg Kosakowski, and Dirk Bosbach
Saf. Nucl. Waste Disposal, 2, 123–124, https://doi.org/10.5194/sand-2-123-2023, https://doi.org/10.5194/sand-2-123-2023, 2023
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Alexandru Tatomir, Milena Schönhofen-Romer, Astrid Göbel, Dinara Abbasova, Thuro Arnold, Vinzenz Brendler, and Kateryna Fuzik
Saf. Nucl. Waste Disposal, 2, 225–226, https://doi.org/10.5194/sand-2-225-2023, https://doi.org/10.5194/sand-2-225-2023, 2023
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Capturing the state of knowledge in radioactive waste management is a very important activity for supporting member states with the implementation of their national programmes towards the safe and effective management of waste. This requires the involvement of experts sharing their expertise and knowledge with the wider community. During the past 3 years, we have gained valuable insights into the procedures of involving experts and knowledge sharing, and the lessons learnt are shown here.
Nicolas Finck, Nikoleta Morelová, Michel L. Schlegel, Dieter Schild, Solenn Reguer, Kathy Dardenne, and Horst Geckeis
Saf. Nucl. Waste Disposal, 2, 39–40, https://doi.org/10.5194/sand-2-39-2023, https://doi.org/10.5194/sand-2-39-2023, 2023
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Stainless steel was exposed to highly saline brines under anoxic and elevated temperature conditions. Samples were analyzed by various techniques in order to identify the nature of the secondary phases present in the corrosion layer forming at the steel–brine interface. Outcomes suggest that the corrosion layer has duplex structure, with an inner layer mostly of chromium (hydr)oxides and an outer layer made of iron- and nickel-based spinel compounds with admixed nickel (hydr)oxides.
Tobias König, Elke Bohnert, Ernesto González-Robles, Michel Herm, Luis Iglesias-Pérez, Volker Metz, Arndt Walschburger, and Horst Geckeis
Saf. Nucl. Waste Disposal, 2, 153–154, https://doi.org/10.5194/sand-2-153-2023, https://doi.org/10.5194/sand-2-153-2023, 2023
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Our contribution focuses on the release of fission gases during the dissolution process of two different types of spent nuclear fuel, i.e. UOX and (U, Pu)OX mixed-oxide fuels, in order to identify and quantify the role of fission gas release rates as an indicator of radionuclide source terms. Within our work, it is shown that, independent of the type of spent nuclear fuel, a comparable, fast initial release of fission gases is evident in all experiments.
Michel Herm, Arndt Walschburger, Tobias König, Volker Metz, and Horst Geckeis
Saf. Nucl. Waste Disposal, 2, 149–150, https://doi.org/10.5194/sand-2-149-2023, https://doi.org/10.5194/sand-2-149-2023, 2023
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This paper presents an experimental investigation of uranium release from spent nuclear fuels under conditions expected in a deep geological repository.
Viktor J. Bruckman, Gregor Giebel, Christopher Juhlin, Sonja Martens, and Michael Kühn
Adv. Geosci., 58, 87–91, https://doi.org/10.5194/adgeo-58-87-2022, https://doi.org/10.5194/adgeo-58-87-2022, 2022
Chaofan Chen, Tao Yuan, Renchao Lu, Cornelius Fischer, Olaf Kolditz, and Haibing Shao
Adv. Geosci., 58, 77–85, https://doi.org/10.5194/adgeo-58-77-2022, https://doi.org/10.5194/adgeo-58-77-2022, 2022
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The moving distance of the diffusion front is farther away the canister center, along the direction with the neighboring layer having lower diffusion coefficient.
When the bedding angle increases, the diffusion front moves farther in z+ direction, reflecting the increase in effective diffusivity and higher impact of parallel-to-bedding diffusion.
The neighboring layers can slightly reshape the diffusion front line of the radionuclide.
Elena Chabab, Michael Kühn, and Thomas Kempka
Adv. Geosci., 58, 47–54, https://doi.org/10.5194/adgeo-58-47-2022, https://doi.org/10.5194/adgeo-58-47-2022, 2022
Short summary
Short summary
The present study, uses density-driven flow and transport models to evaluate mechanisms of saline water intrusion from deep aquifers into the freshwater column used for drinking water supply under different boundary conditions and for a specific site in the German Federal State of Brandenburg. Results show that mainly decreasing groundwater recharge leads to increased and earlier salinisation which highlights the need for waterworks to initiate effective countermeasures quickly and in time.
Michael Kühn, Melissa Präg, Ivy Becker, Christoph Hilgers, Andreas Grafe, and Thomas Kempka
Adv. Geosci., 58, 31–39, https://doi.org/10.5194/adgeo-58-31-2022, https://doi.org/10.5194/adgeo-58-31-2022, 2022
Short summary
Short summary
The geothermal hot water reservoir below the small town of Waiwera in New Zealand has been known to the indigenous Maori for many centuries. Overproduction by European immigrants led to a water level decrease and consequently artesian flow from the wells and the seeps on the beach ceased. The Te Kaunihera o Tāmaki Makaurau Auckland Council established the Waiwera Thermal Groundwater Allocation and Management Plan to allow the geothermal system to recover.
Thomas Kempka, Svenja Steding, and Michael Kühn
Adv. Geosci., 58, 19–29, https://doi.org/10.5194/adgeo-58-19-2022, https://doi.org/10.5194/adgeo-58-19-2022, 2022
Short summary
Short summary
The TRANSPORT Simulation Environment (TRANSPORTSE) was coupled with the geochemical reaction module PHREEQC, providing multiple new features that make it applicable to complex reactive transport problems in various geoscientific fields. Two computationally demanding and complex geochemical benchmarks were used in the present study to successfully verify the code implementation.
Theresa Hennig and Michael Kühn
Adv. Geosci., 58, 11–18, https://doi.org/10.5194/adgeo-58-11-2022, https://doi.org/10.5194/adgeo-58-11-2022, 2022
Short summary
Short summary
Safety assessments must demonstrate that radionuclides in potential disposal sites are retained within the containment providing rock zone using reactive transport simulations. Here, this is quantified for the example of uranium in the hydrogeological system of the Opalinus Clay at Mont Terri. Our work clearly shows how sensitive migration lengths resulting from simulations are to the model conceptualisation and selection of underlying data.
Maria Wetzel, Thomas Kempka, and Michael Kühn
Adv. Geosci., 58, 1–10, https://doi.org/10.5194/adgeo-58-1-2022, https://doi.org/10.5194/adgeo-58-1-2022, 2022
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Porosity-permeability relations are simulated for a precipitation-dissolution cycle in a virtual sandstone. A hysteresis in permeability is observed depending on the geochemical process and dominating reaction regime, whereby permeability varies by more than two orders of magnitude. Controlling parameters for this hysteresis phenomenon are the closure and re-opening of micro-scale flow channels, derived from changes in pore throat diameter and connectivity of the pore network.
Marco De Lucia, Michael Kühn, Alexander Lindemann, Max Lübke, and Bettina Schnor
Geosci. Model Dev., 14, 7391–7409, https://doi.org/10.5194/gmd-14-7391-2021, https://doi.org/10.5194/gmd-14-7391-2021, 2021
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POET is a parallel reactive transport simulator which implements a mechanism to store and reuse previous results of geochemical simulations through distributed hash tables. POET parallelizes chemistry using a master/worker design with noncontiguous grid partitions to maximize its efficiency and load balance on shared-memory machines and compute clusters.
Michael Kühn and Leonard Grabow
Adv. Geosci., 56, 107–116, https://doi.org/10.5194/adgeo-56-107-2021, https://doi.org/10.5194/adgeo-56-107-2021, 2021
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The geothermal reservoir at Waiwera has been subject to active exploitation for a long time. However, the continuous production of geothermal water, to supply hotels and spas, had a negative impact on the reservoir. The aim of this work was to link the influence of the abstraction rates to the measured water level data to derive reservoir properties. For the analysis, a modified deconvolution algorithm was implemented and shown to be applicable and in accordance to results of a pumping test.
Michel Herm, Elke Bohnert, Luis Iglesias Pérez, Tobias König, Volker Metz, Arndt Walschburger, and Horst Geckeis
Saf. Nucl. Waste Disposal, 1, 237–238, https://doi.org/10.5194/sand-1-237-2021, https://doi.org/10.5194/sand-1-237-2021, 2021
Tobias König, Ron Dagan, Kathy Dardenne, Michel Herm, Volker Metz, Tim Pruessmann, Jörg Rothe, Dieter Schild, Arndt Walschburger, and Horst Geckeis
Saf. Nucl. Waste Disposal, 1, 5–6, https://doi.org/10.5194/sand-1-5-2021, https://doi.org/10.5194/sand-1-5-2021, 2021
Mara I. Lönartz, Jenna Poonoosamy, Yuankai Yang, Naila Ait-Mouheb, Guido Deissmann, and Dirk Bosbach
Saf. Nucl. Waste Disposal, 1, 181–182, https://doi.org/10.5194/sand-1-181-2021, https://doi.org/10.5194/sand-1-181-2021, 2021
Felix Brandt, Martina Klinkenberg, Sébastien Caes, Jenna Poonoosamy, Wouter Van Renterghem, Juri Barthel, Karel Lemmens, Dirk Bosbach, and Karine Ferrand
Saf. Nucl. Waste Disposal, 1, 143–144, https://doi.org/10.5194/sand-1-143-2021, https://doi.org/10.5194/sand-1-143-2021, 2021
Philip Kegler, Martina Klinkenberg, Felix Brandt, Guido Deissmann, and Dirk Bosbach
Saf. Nucl. Waste Disposal, 1, 91–93, https://doi.org/10.5194/sand-1-91-2021, https://doi.org/10.5194/sand-1-91-2021, 2021
M. Carme Chaparro, Nicolas Finck, Volker Metz, and Horst Geckeis
Saf. Nucl. Waste Disposal, 1, 169–170, https://doi.org/10.5194/sand-1-169-2021, https://doi.org/10.5194/sand-1-169-2021, 2021
Astrid Göbel, Tobias Knuuti, Carola Franzen, Dinara Abbasova, Thuro Arnold, Vinzenz Brendler, Kateryna Fuzik, Jiří Faltejsek, Bálint Nős, Nadja Železnik, and Jitka Mikšová
Saf. Nucl. Waste Disposal, 1, 249–250, https://doi.org/10.5194/sand-1-249-2021, https://doi.org/10.5194/sand-1-249-2021, 2021
Nikoleta Morelová, Kathy Dardenne, Nicolas Finck, Frank Heberling, Volker Metz, Dieter Schild, Horst Geckeis, and Nikitas Diomidis
Saf. Nucl. Waste Disposal, 1, 103–104, https://doi.org/10.5194/sand-1-103-2021, https://doi.org/10.5194/sand-1-103-2021, 2021
Jenna Poonoosamy, Martina Klinkenberg, Mara Lönartz, Yuankai Yang, Guido Deissmann, Felix Brandt, and Dirk Bosbach
Saf. Nucl. Waste Disposal, 1, 105–107, https://doi.org/10.5194/sand-1-105-2021, https://doi.org/10.5194/sand-1-105-2021, 2021
Xavier Gaona, Marcus Altmaier, Iuliia Androniuk, Nese Çevirim-Papaioannou, Michel Herm, Luis Iglesias-Perez, Yongheum Jo, Volker Metz, Andrej Skerencak-Frech, Agost Tasi, and Horst Geckeis
Saf. Nucl. Waste Disposal, 1, 151–152, https://doi.org/10.5194/sand-1-151-2021, https://doi.org/10.5194/sand-1-151-2021, 2021
Irmgard Niemeyer, Katharina Aymanns, Guido Deissmann, and Dirk Bosbach
Saf. Nucl. Waste Disposal, 1, 241–242, https://doi.org/10.5194/sand-1-241-2021, https://doi.org/10.5194/sand-1-241-2021, 2021
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The presentation will introduce the objectives of international nuclear material safeguards for the final disposal of spent nuclear fuel, highlight the current status of developments and discussions in terms of approaches and technologies for safeguarding spent fuel encapsulation and geological repository facilities, and give an outlook on implementing safeguards for final disposal in Germany.
Dirk Bosbach and Lena Z. Evins
Saf. Nucl. Waste Disposal, 1, 233–234, https://doi.org/10.5194/sand-1-233-2021, https://doi.org/10.5194/sand-1-233-2021, 2021
Dirk Bosbach, Crina Bucur, and Christophe Bruggeman
Saf. Nucl. Waste Disposal, 1, 235–236, https://doi.org/10.5194/sand-1-235-2021, https://doi.org/10.5194/sand-1-235-2021, 2021
Naila Ait-Mouheb, Yuankai Yang, Luc R. Van Loon, Martin A. Glaus, Guido Deissmann, and Dirk Bosbach
Saf. Nucl. Waste Disposal, 1, 141–142, https://doi.org/10.5194/sand-1-141-2021, https://doi.org/10.5194/sand-1-141-2021, 2021
Helge C. Moog, Tina Scharge, Holger Seher, Frank Bok, Vinzenz Brendler, Anke Richter, Laurin Wissmeier, Marcus Altmaier, Xavier Gaona, Nese Cevirim-Papaioannou, Daniela Freyer, Melanie Pannach, Julia Sohr, and Wolfgang Voigt
Saf. Nucl. Waste Disposal, 1, 157–158, https://doi.org/10.5194/sand-1-157-2021, https://doi.org/10.5194/sand-1-157-2021, 2021
Daniel Glückman, Karin Hain, Claudia Joseph, Volker Metz, Francesca Quinto, Peter Steier, and Horst Geckeis
Saf. Nucl. Waste Disposal, 1, 153–154, https://doi.org/10.5194/sand-1-153-2021, https://doi.org/10.5194/sand-1-153-2021, 2021
Dirk Bosbach, Horst Geckeis, Frank Heberling, Olaf Kolditz, Michael Kühn, Katharina Müller, Thorsten Stumpf, and the iCROSS team
Saf. Nucl. Waste Disposal, 1, 85–87, https://doi.org/10.5194/sand-1-85-2021, https://doi.org/10.5194/sand-1-85-2021, 2021
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The present contribution provides an overview on the collaborative project iCROSS and reports selected results. The impact of considering complex coupled processes in repository subsystems for the assessment of the integrity of a given (generic) repository arrangement will be discussed. The interdisciplinary team combines experimental work in the lab, in the underground rock laboratory and environmental simulations in order to achieve process understanding across variable scales.
René Kahnt, Heinz Konietzky, Thomas Nagel, Olaf Kolditz, Andreas Jockel, Christian B. Silbermann, Friederike Tiedke, Tobias Meisel, Karsten Rink, Wenqing Wang, Florian Zill, Antje Carl, Aron D. Gabriel, Marcel Schlegel, and Torsten Abraham
Saf. Nucl. Waste Disposal, 1, 175–177, https://doi.org/10.5194/sand-1-175-2021, https://doi.org/10.5194/sand-1-175-2021, 2021
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In the framework of the Site Selection Act – StandAG, the geoscientific and planning requirements and criteria for the site selection for a repository for high-active nuclear waste are specified. This includes, among others, the modelling of hydrogeological scenarios such as how future cold and warm periods and associated glaciation events can change the (petro-)physical properties as well as the natural hydrogeological properties of the overall system which is the focus of the AREHS project.
David Fellhauer, Xavier Gaona, Marcus Altmaier, and Horst Geckeis
Saf. Nucl. Waste Disposal, 1, 149–150, https://doi.org/10.5194/sand-1-149-2021, https://doi.org/10.5194/sand-1-149-2021, 2021
Gesa Ziefle, Tuanny Cajuhi, Sebastian Condamin, Stephan Costabel, Oliver Czaikowski, Antoine Fourriére, Larissa Friedenberg, Markus Furche, Nico Graebling, Bastian Graupner, Jürgen Hesser, David Jaeggi, Kyra Jantschik, Tilo Kneuker, Olaf Kolditz, Franz Königer, Herbert Kunz, Ben Laurich, Jobst Maßmann, Christian Ostertag-Henning, Dorothee Rebscher, Karsten Rink, Wolfram Rühaak, Senecio Schefer, Rainer Schuhmann, Marc Wengler, and Klaus Wieczorek
Saf. Nucl. Waste Disposal, 1, 79–81, https://doi.org/10.5194/sand-1-79-2021, https://doi.org/10.5194/sand-1-79-2021, 2021
Andrej Skerencak-Frech, Petra Panak, Kathy Dardenne, Jörg Rothe, Xavier Gaona, Marcus Altmaier, and Horst Geckeis
Saf. Nucl. Waste Disposal, 1, 159–160, https://doi.org/10.5194/sand-1-159-2021, https://doi.org/10.5194/sand-1-159-2021, 2021
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An overview on the recent advances in the field of high temperature studies of radionuclides in aqueous solutions will be given. Besides summarizing information on key technical aspects relevant for high temperature studies, the effect of increased temperatures on the complexation of trivalent actinides with chloride will be discussed in more detail, to illustrate newly derived in-depth understanding of the impact of increased temperatures on the (geo)chemical behaviour of trivalent actinides.
Theresa Hennig and Michael Kühn
Adv. Geosci., 56, 97–105, https://doi.org/10.5194/adgeo-56-97-2021, https://doi.org/10.5194/adgeo-56-97-2021, 2021
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Uranium migration in the Swiss Opalinus Clay is used as an example to quantify the influence of varying values of a stability constant in the underlying thermodynamic database within the law of mass action on the migration lengths. The difference of the stability constant of 1.33 log units lead to changed migration lengths of 5 m to 7 m. With a maximum diffusion distance of 22 m the influence of an uncertain stability constant is negligible for the host rock scale.
Morgan Tranter, Maria Wetzel, Marco De Lucia, and Michael Kühn
Adv. Geosci., 56, 57–65, https://doi.org/10.5194/adgeo-56-57-2021, https://doi.org/10.5194/adgeo-56-57-2021, 2021
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Barite formation is an important factor for many use cases of the geological subsurface because it may change the rock.
In this modelling study, the replacement reaction of celestite to barite is investigated.
The steps that were identified to play a role are celestite dissolution followed by two-step precipitation of barite: spontaneous formation of small crystals and their subsequent growth.
Explicitly including the processes improve the usability of the models for quantified prediction.
Marco De Lucia and Michael Kühn
Adv. Geosci., 56, 33–43, https://doi.org/10.5194/adgeo-56-33-2021, https://doi.org/10.5194/adgeo-56-33-2021, 2021
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RedModRphree is an R extension package to leverage the PHREEQC engine for geochemical models, providing convenience functions to efficiently setup computations and program algorithms involving geochemical models. Version 0.3.6 ships with a novel implementation of Pourbaix (potential/pH) diagram computation which considers the full speciation of the solution at each diagram point.
Viktor J. Bruckman, Gregor Giebel, Christopher Juhlin, Sonja Martens, Antonio P. Rinaldi, and Michael Kühn
Adv. Geosci., 56, 13–18, https://doi.org/10.5194/adgeo-56-13-2021, https://doi.org/10.5194/adgeo-56-13-2021, 2021
Marco De Lucia and Michael Kühn
Geosci. Model Dev., 14, 4713–4730, https://doi.org/10.5194/gmd-14-4713-2021, https://doi.org/10.5194/gmd-14-4713-2021, 2021
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DecTree evaluates a hierarchical coupling method for reactive transport simulations in which pre-trained surrogate models are used to speed up the geochemical subprocess, and equation-based
full-physicssimulations are called only if the surrogate predictions are implausible. Furthermore, we devise and evaluate a decision tree surrogate approach designed to inject domain knowledge of the surrogate by defining engineered features based on law of mass action or stoichiometric reaction equations.
Melissa Präg, Ivy Becker, Christoph Hilgers, Thomas R. Walter, and Michael Kühn
Adv. Geosci., 54, 165–171, https://doi.org/10.5194/adgeo-54-165-2020, https://doi.org/10.5194/adgeo-54-165-2020, 2020
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Utilization of geothermal reservoirs as alternative energy source is becoming increasingly important worldwide. Here, we studied the surface expression of a warm water reservoir in Waiwera, New Zealand, that has been known for many centuries but remained little explored. Using thermal infrared cameras we were able to show renewed activity of the hot springs on the beachfront and identified faults and fractures as important fluid pathways, as well as individual fluid conducting lithologies.
Michael Kühn, Natalie C. Nakaten, and Thomas Kempka
Adv. Geosci., 54, 173–178, https://doi.org/10.5194/adgeo-54-173-2020, https://doi.org/10.5194/adgeo-54-173-2020, 2020
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Energy supply in Germany is subject to a profound change. The present paper addresses the German potential of storing excess energy from renewable power sources in the geological subsurface. Wind and solar electricity can be transformed into hydrogen, and with carbon dioxide subsequently into methane. The current potential for combined subsurface storage of methane and carbon dioxide allows to store far more than required to date and is estimated to provide the entire coverage in 2050.
Maria Wetzel, Thomas Kempka, and Michael Kühn
Adv. Geosci., 54, 33–39, https://doi.org/10.5194/adgeo-54-33-2020, https://doi.org/10.5194/adgeo-54-33-2020, 2020
Sonja Martens, Maren Brehme, Viktor J. Bruckman, Christopher Juhlin, Johannes Miocic, Antonio P. Rinaldi, and Michael Kühn
Adv. Geosci., 54, 1–5, https://doi.org/10.5194/adgeo-54-1-2020, https://doi.org/10.5194/adgeo-54-1-2020, 2020
Márk Somogyvári, Michael Kühn, and Sebastian Reich
Adv. Geosci., 49, 207–214, https://doi.org/10.5194/adgeo-49-207-2019, https://doi.org/10.5194/adgeo-49-207-2019, 2019
Sonja Martens, Christopher Juhlin, Viktor J. Bruckman, Gregor Giebel, Thomas Nagel, Antonio P. Rinaldi, and Michael Kühn
Adv. Geosci., 49, 31–35, https://doi.org/10.5194/adgeo-49-31-2019, https://doi.org/10.5194/adgeo-49-31-2019, 2019
Miao Jing, Falk Heße, Rohini Kumar, Olaf Kolditz, Thomas Kalbacher, and Sabine Attinger
Hydrol. Earth Syst. Sci., 23, 171–190, https://doi.org/10.5194/hess-23-171-2019, https://doi.org/10.5194/hess-23-171-2019, 2019
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We evaluated the uncertainty propagation from the inputs (forcings) and parameters to the predictions of groundwater travel time distributions (TTDs) using a fully distributed numerical model (mHM-OGS) and the StorAge Selection (SAS) function. Through detailed numerical and analytical investigations, we emphasize the key role of recharge estimation in the reliable predictions of TTDs and the good interpretability of the SAS function.
Michael Kühn and Tim Schöne
Adv. Geosci., 45, 235–241, https://doi.org/10.5194/adgeo-45-235-2018, https://doi.org/10.5194/adgeo-45-235-2018, 2018
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The water level of the Waiwera geothermal reservoir increased in the hours and days after the Kaikoura earthquake on 14 November 2016. We determined in a continuous time series consisting of monthly means of water level data and pumping rates starting in 1986 if events above a certain strength alter groundwater dynamics at Waiwera. A clear correlation cannot be proven but none of the recorded earthquakes led to such a high energy density in Waiwera as the Kaikoura event did.
Sonja Martens, Christopher Juhlin, Viktor J. Bruckman, Kristen Mitchell, Luke Griffiths, and Michael Kühn
Adv. Geosci., 45, 163–166, https://doi.org/10.5194/adgeo-45-163-2018, https://doi.org/10.5194/adgeo-45-163-2018, 2018
Miao Jing, Falk Heße, Rohini Kumar, Wenqing Wang, Thomas Fischer, Marc Walther, Matthias Zink, Alraune Zech, Luis Samaniego, Olaf Kolditz, and Sabine Attinger
Geosci. Model Dev., 11, 1989–2007, https://doi.org/10.5194/gmd-11-1989-2018, https://doi.org/10.5194/gmd-11-1989-2018, 2018
Elena Tillner, Maria Langer, Thomas Kempka, and Michael Kühn
Hydrol. Earth Syst. Sci., 20, 1049–1067, https://doi.org/10.5194/hess-20-1049-2016, https://doi.org/10.5194/hess-20-1049-2016, 2016
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The degree of shallow aquifer salinisation triggered by fluid injection into deeper brine-bearing aquifers and brine upward migration through hydraulically conductive faults strongly depends on the regional depth of the freshwater-saltwater boundary, since displaced brines originate only from the upper fault damage zones in the study area. The highest local salinity increase in shallow aquifers occurs in case of closed model boundaries and low fault damage zone volumes.
T. Fischer, D. Naumov, S. Sattler, O. Kolditz, and M. Walther
Geosci. Model Dev., 8, 3681–3694, https://doi.org/10.5194/gmd-8-3681-2015, https://doi.org/10.5194/gmd-8-3681-2015, 2015
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We present a workflow to convert geological models into the open-source VTU format for usage in numerical simulation models. Tackling relevant scientific questions or engineering tasks often involves multidisciplinary approaches. Conversion workflows are needed between the diverse tools of the various disciplines. Our approach offers an open-source, platform-independent, robust, and comprehensible method that is potentially useful for a multitude of similar environmental studies.
W. He, C. Beyer, J. H. Fleckenstein, E. Jang, O. Kolditz, D. Naumov, and T. Kalbacher
Geosci. Model Dev., 8, 3333–3348, https://doi.org/10.5194/gmd-8-3333-2015, https://doi.org/10.5194/gmd-8-3333-2015, 2015
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This technical paper presents a new tool to simulate reactive transport processes in subsurface systems and which couples the open-source software packages OpenGeoSys and IPhreeqc. A flexible parallelization scheme was developed and implemented to enable an optimized allocation of computer resources. The performance tests of the coupling interface and parallelization scheme illustrate the promising efficiency of this generally valid approach to simulate reactive transport problems.
M. De Lucia, T. Kempka, and M. Kühn
Geosci. Model Dev., 8, 279–294, https://doi.org/10.5194/gmd-8-279-2015, https://doi.org/10.5194/gmd-8-279-2015, 2015
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The Repository Site Selection Act explicitly emphasises that targeting the disposal of high-level radioactive waste is a so-called learning process. We are of the opinion that the procedure and the available data should be combined with geoscientific knowledge to support the identification of siting regions. We propose this workshop and invite all experts who have dealt with the search for a repository site from a geoscientific perspective.
The Repository Site Selection Act explicitly emphasises that targeting the disposal of...
