Interplay of free convection and chemical reactions in groundwater below salt lakes
The project is financed by the German Science Foundation (DFG; FKZ: KO 3186/1-1)
Besides their particular value as biological habitats and indicators for climatic changes, salt lakes are important for water resource management as lake induced salinisation may strongly affect the groundwater quality in their vicinity. Owing to density driven flow coupled with chemical reactions the interaction and mass transfer between salt lakes and groundwater is extremely complex.
Based on the results of recent studies our working hypothesis is that chemical reactions alter density driven flow patterns and are relevant for explaining physico-chemical processes below salt lakes showing a much more complex network of chemical reactions. Furthermore we expect that density driven flow also alters the hydrochemistry during evaporation owing to the removal of highly concentrated brines.
The general objective of this study is to investigate the feedback between density driven flow and chemical reactions under different conditions and to explore the role of heterogeneity and climatic or hydrologic conditions at different tempo-spatial scales. This will be achieved by numerical studies using coupled variable density driven flow and multi-component reactive transport model codes.
Simulations will start with one-dimensional conceptual settings with homogeneous and isotropic parameter distributions with stepwise increasing complexity and will be extended to conceptual vertical two-dimensional scenarios. After a refined understanding of the feedback mechanisms has been obtained, the model will be applied to two different field sites, the Raak Plains (Australia) and Fuente de Piedra Salt Lake (Spain).
Dr. Kohfahl (IGME, Spain), Dr. Hamann (FUB)
Enrico Hamann, firstname.lastname@example.org