09 Nov 2021
| 09 Nov 2021
Uranium migration through the Swiss Opalinus Clay varies on the metre scale in response to differences of the stability constant of the aqueous, ternary uranyl complex Ca2UO2(CO3)3
Theresa Hennig
CORRESPONDING AUTHOR
GFZ German Research Centre for Geosciences, Fluid Systems Modelling, Telegrafenberg, 14473 Potsdam, Germany
University of Potsdam, Institute of Geosciences, Karl-Liebknecht-Str. 24-25, 14476 Potsdam-Golm, Germany
Michael Kühn
GFZ German Research Centre for Geosciences, Fluid Systems Modelling, Telegrafenberg, 14473 Potsdam, Germany
University of Potsdam, Institute of Geosciences, Karl-Liebknecht-Str. 24-25, 14476 Potsdam-Golm, Germany
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Short summary
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.
Uranium migration in the Swiss Opalinus Clay is used as an example to quantify the influence of...
