Multi-scale approach for geomechanical-numerical Models

Focus of the subproject at the GFZ Potsdam is the development of tools that allow a consistent stress prediction between the Germany model and the local scale models (see figure). The Germany model is supposed to deliver initial stress conditions for regional and final for local model in a multi-scale approach. All of the work is host rock-independent and provides the basics and modelling tools for geomechanical local models that are required in the future without being limited to specific siting areas. Furthermore, modelling techniques for the selection of suitable scale-dependent rock or rock parameters as well as concepts for the representative calibration data required for a corresponding model volume are investigated.

Database for stress magnitudes

The World Stress Map project compiles stress information and provides it in a unique global database. However, the database is limited to data for the orientation of the stress tensor and the stress regime. Data on stress magnitudes are not yet systematically compiled. Since these data are of key importance for the quality of the model calibration, stress magnitude data is compiled in this subproject for Germany and adjacent areas. Furthermore, a quality-ranking scheme will be developed that captures these data according to their qualities. These can then be used as weights in the model calibration process.

Figure: Sketch of a multi-stage approach from a large-scale model that delivers step-wise initial conditions for smaller scale models modified after Reiter and Heidbach (2014) and Ziegler et al. (2017).