Modelling tectonics and sedimentation of the Late Carboniferous Variscan Foreland in Northwestern Europe

摘要

The dynamics of the Northwestern European Variscan Foreland basins during the Carboniferous has been recently reviewed in several Case studies. In this study we will concentrate on the evolution of the Upper Carboniferous successions in Germany and adjacent basins in Belgium and the Netherlands, which document the contribution of the different mechanisms and show some new numerical approaches to review the existing theories. Quantitative siratigraphic modelling of the Ruhr Basin (Germany) provided the possibility for a compilation of a high-resolution time scale for use in the Northwestern European Variscan Foreland basins. Stratigraphic correlation of wells from coal mining led to an estimation of the accumulation of sediments in the Ruhr Basin and adjacent Aachen Basin. Calculated subsidence curves. cross-sections, and thickness maps revealed a moving structural high in the Ruhr Basin during the deposition of the strata. due to the approaching Variscan orogen. Quantitative 2D-numerical simulations provide alternative geodynamic interpretations of this geomorphologic element. The results verify the governing basin mechanisms in the Northwestern European Variscan Foreland. The simulations incorporated loading effects and stresses of the advancing plates as well as long-term erosional/depositional dynamics of the evolving orogenic wedge and the basin. The applied techniques facilitated an evaluation of the balance between the denudation of the Variscan orogen and the accumulation of sediments in the basin. The resulting models explain the depositional geometry and related stratigraphic surfaces. which generally form in foreland basins.