The recent crustal stress field in Central Europe sensu lato and its quantitative modelling

Abstract

A detailed pattern of trajectories of the direction of maximum horizontal crustal stresses SHmax has been derived for Central Europe sensu lato according to actual data on fault plane solutions, in-situ stress measurements, geologic fault slip determinations and geodetic information. The generalization of this direction data on maximum compressive stress in the form of trajectories shows a bending from the well-established NW-SE direction in western parts of the study area to directions of NE-SW to E-W in the eastern part. In some regions there is evidence for a more complicated pattern, e.g. apparently differing SHmax-directions in different depth horizons, stress deflections at pronounced tectonic complexes, and radial directions around the Pannonian Basin. For studying the conditions in the brittle part of the crust steady-state elastic finite-element model calculations were carried out to explain the observed stress orientations. It is shown that the simulation according to a modern plate tectonic concept leads to a pattern of main principal stress directions that is compatible with the generalized observed stress directions. More regional features were modelled by reasonable variation of elastic parameters of different lithospheric blocks.