A robust prediction of the recent crustal stress field has a crucial role for forecasting the short- and long-term safety of a high-level radioactive waste repository. However, no reliable and comprehensive prediction of the complete stress tensor for Germany is possible with the amount of stress data records available. The only comprehensive data set is the World Stress Map, which, however, only provides the orientation of the maximum horizontal stress. Stress magnitude data records of sufficiently reliable quality are only available from a few boreholes. However, 3D geomechanical-numerical models, which represent the geometry of the subsurface and its mechanical properties and are calibrated with stress magnitudes, allow a continuum-mechanics based prediction of the complete stress tensor and its lateral and vertical variability.
A new geomechanical-numerical model – developed within the SpannEnD 2.0 (Spannungsmodell Endlagerung Deutschland) project - provides new insights into the recent crustal stress field of Germany. A new model, by combining ~25 existing 3D geological models and a five time higher vertical resolution of ~45 m allow a better mechanical representation of individual units and mechanical inhomogeneities. In addition new stress magnitude data records are compiled and used for calibration.
The results provide a comprehensive prediction of the complete stress tensor for Germany and can be used for a wide range of scientific questions and applications. Examples are the prediction of the fracture potential, the slip tendency of faults or as boundary conditions for small-scale models.