The paleostress history of the Central European Basin System
Zum Verlinken/Bookmarken: http://dx.doi.org/10.23689/fidgeo-493
The Central European Basin System (CEBS) is a complex intracontinental system of sedimentary basins that have evolved through several geodynamic phases since Late Carboniferous times. The basin system is framed by the Tornquist Zone in the north and the Elbe Fault System in the south. The main structural configuration of the basin system is well established due to decades of scientific research and intense industrial exploration for mineral resources. The scope of this PhD thesis is to assess which paleostress fields controlled the evolution of the basin system. The present thesis introduces the "Stress Inversion via Simulation" (SVS) as a new strategy for estimating paleostress states. For a set of striated fault planes with known sense of slip (fault-slip data), this stepwise technique identifies the corresponding "reduced stress tensor" comprising (1) the directions of the principal stress axes with sigma1?sigma2?sigma3 and (2) the ratio of principal stress differences, R=(sigma2-sigma3)/(sigma1-sigma3). For heterogeneous fault-slip data, SVS separates the different corresponding "reduced stress tensors". Any estimated stress tensor thereby fulfils both the criterion of low misfit angles and the criterion of high shear-to-normal-stress ratios for the associated fault-slip data. The base for the present study is provided by fault-slip data gathered from outcrops in the Elbe Fault System area (906 fault-slip data) and in the Oslo Graben area north of the Tornquist Zone (2191 data). 77 paleostress tensors have been estimated for the Elbe Fault System area and 194 tensors for the Oslo Graben area ...