| Summary: | Tectonic studies made in intraplate Europe have shown that this area is more active than would be expected from its location far away from plate boundaries.The first strength map showed that the European lithosphere is characterized by major spatial mechanical strength variations, with a pronounced contrast between the strong lithosphere of the East-European Platform (EEP) east of the Tesseyre-Tornquist Zone (TTZ) and the relatively weak lithosphere of Western Europe. In order to improve the results previously obtained, we have constructed a new crustal model, in which we implement the results of recent seismic studies. The new crustal model consists for continental realms, of two or three crustal layers and an overlying sedimentary cover layer, whereas for oceanic areas one crustal layer is used. The results of deep seismic reflection and refraction and/or receiver function studies are used to define the depth of the crustal interfaces and P-wave velocity distribution. The Moho depth variations are reconstructed by merging the most recent maps compiled for the European regions (e.g. Ziegler and Dèzes, 2002, Kozlovskaja et al, 2004) and by ourselves using published interpretations of seismic profiles (e.g. in the Vøring and Lofoten basins). To each layer of the model we associate a density value and corresponding lithology. Strong differences in the crustal structure are found between the areas east and west of the TTZ, respectively. The eastern region is mostly characterized by high velocity of the lowest layer (Vp~7.1km/s) and thick crust, e.g. over the Baltica region (42-44km) with a maximum of over 60 km in the Baltic Shield. By contrast, crustal structure is more heterogeneous to the west from TTZ, being characterized by Variscan crust with slower P-wave velocity in the lower crust (Vp~6.8km/s) and an average thickness of 30-35 km, orogens (e.g. the Alps and the Pyrenees), where the crustal thickness is increased up to 45-50 km, and locally by strong extensional deformation, which resulted in a very thin ...
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