The recent stress state of Germany – results of a geomechanical–numerical 3D model

Abstract. A decisive criterion for the selection and long-term safety of a deep geological repository high radioactive waste is crustal stress state its future changes. The basis any prognosis recent state, but knowledge in Germany quite low this respect. There are orientation data provided by World Stress Map (WSM, Heidbach et al., 2018) magnitude from database (Morawietz 2020) Germany, both providing selective information on field. However, these often incomplete, quality spatially unevenly distributed. Therefore, 3D continuous description not possible with so far, at most maximum horizontal (SHmax), important magnitudes minimum (Shmin) SHmax. In course SpannEnD project, geomechanical–numerical model created, which complete tensor field possible. covers an area 1250×1000 km2 Poland east, to France west, Italy south Scandinavia north. depth extent 100 km. Even though focus primarily was chosen be wide minimize boundary effects simplified definition displacement conditions, ideally oriented perpendicular or parallel contains total 21 units: upper part lithospheric mantle, lower crust, four laterally overlapping units 14 stratigraphic sedimentary cover. subdivision cover only done core model; because our study, calibration mainly region well-resolved geometry available. Outside area, sediments grouped into undifferentiated unit. parameterized density elastic material parameters (Poisson's ratio Young's modulus). has lateral resolution 2.5×2.5 vertical 240 m; it includes 11.1 million hexahedral elements. equilibrium forces between body surface solved finite element method. calibrated Shmin SHmax WSM database. First, initial generated second step conditions defined edges, adjusted until best-fit found. results show good agreement two principal stresses (Shmin SHmax)