Universität Basel
Angewandte & Umweltgeologie
Departement Umweltwissenschaften

Subrosion (NF)

Prof. Dr. P. Huggenberger, Dr. E. Zechner, Dr. A. Zidane, A. Younes, P. Ackerer, G. Gassner

The ongoing SNF-project aims to improve the understanding of modeling variable density flow for different structural geological settings and complex hydraulic constraints. Research on a field example focuses on studying the subsidence hazard in urban areas caused by salt dissolution in the Tabular Jura of Northwestern Switzerland. In addition, the results from this research will be able to help interpret recently monitored pollution patterns in the same area, which are only poorly understood when using commonly applied approaches in groundwater monitoring.

Based on previous research results, we propose the following procedure: A) Realization of selected 2D laboratory experiments, B) Numerical 2D simulations of existing instable flow laboratory results, C) Numerical 2D simulations of selected cross-sections based on field data and structures, and D) 3D simulations of density-driven flow with data from field structures. Objectives of the 2D laboratory experiments are to provide a reliable database to improve the knowledge of the physical density-flow phenomena such as the possible relationship between solute concentration and dispersivity. Further, the experiments will be used as a benchmark to test numerical codes under instable and heterogeneous flow conditions. The proposed 2D simulations at laboratory scale will allow general strategies to be developed, which will lead to a greater understanding of the influence and sensitivity of artificial perturbations such as sinusoidal fluctuations of boundary flow, or different forms of heterogeneity distributions on density flow. 2D simulations of selected cross-sections based on field data will improve our understanding of the driving forces such as hydraulic boundary conditions and tectonic structures on subrosion. As opposed to 3D simulations, the 2D simulations allow the analysis of a set of models with a significantly reduced CPU-time. Finally, the knowledge gained will contribute to a 3D simulation of density flow with data from field structures. Two different field scenarios will be investigated. Firstly, the subrosion problem will be simulated under stable flow conditions. Secondly, field data of plume migration from a landfill will be reinterpreted with the simulation of unstable flow conditions.

The research focuses on the continuation of the successful cooperation between the Applied and Environmental Geology research group at the University of Basel, and the "Laboratoire d’Hydrologie et de Geochimie"" at the University of Strasbourg.