Conference Abstract
| 
06 Sep 2023
Conference Abstract |
| 06 Sep 2023
| 06 Sep 2023
Hydrogeochemical impact of Opalinus Clay system shown in migration lengths of uranium
Theresa Hennig
CORRESPONDING AUTHOR
GFZ German Research Centre for Geosciences, Potsdam 14473, Germany
Michael Kühn
GFZ German Research Centre for Geosciences, Potsdam 14473, Germany
University of Potsdam, Institute of Geosciences, Golm (Potsdam)
14476, Germany
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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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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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Sonja Martens, Christopher Juhlin, Viktor J. Bruckman, Kristen Mitchell, Luke Griffiths, and Michael Kühn
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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
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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.
Migration of uranium in the potential host rock Opalinus Clay is used as an example to...
