Upper mantle controls on the Paleozoic to Cenozoic evolution of intracontinental Western and Central Europe

Shear-wave tomography models of the upper mantle below intracontinental Central Europe are indicative of a thermally very heterogeneous lithosphere-asthenosphere system. Low shear-wave velocities indicate the presence of a deep 1300 degC isotherm and thus thick (200 km) lithosphere in the SW North Sea and the Paris Basin, which contrasts with a shallower (< 120 km) lithosphere-asthenosphere boundary observed across the ECRIS and much of the British Isles. These major, long-wavelength depth fluctuations of the thermal boundary layer are locally superposed by a number of smaller-scale thermal anomalies situated within the lithospheric mantle (such as the Eifel mantle thermal anomaly). In an earlier study, we discussed how present-day density and strength variations in the mantle lithosphere may affect the distribution of earthquakes in this intraplate setting. With this new contribution, we focus on discussing potential ages of those upper mantle thermal anomalies in an attempt to delineate their roles in the geological past. The overlying crystalline crust and sediments provide us with records of a multiphase tectonic and sedimentary evolution that extends from Paleozoic to Cenozoic times. To better understand upper mantle controls on crustal deformation phases, we investigate spatial correlations between upper mantle temperature variations as derived from shear-wave tomography models with major crustal structures of known geological age and setting. We will also discuss existing correlations in the light of thermal field variations across the lithosphere produced by numerical simulations of conductive heat transport.