Abstract EN:

The crustal architecture of the present Pyrenean range leads us to identify four seismotectonic units, from east to west (1) the Eastern Pyrenees (2) the Eastern and (3) Western Central Pyrenees and (4) the Western Pyrenees. These units are affected by two different seismicity patterns. The first mode of deformation is triggered by the relative oblique convergence between the Iberian and European plates whereas the second is a consequence of the isostatic exhumation of the mountain ranges, induced by erosion of the thick under-thrusted Iberian crust. In the Western Central Pyrenees, we show Plio-Pleistocene tectonic activity related to the occurrence of a potential seismogenic source in the Arudy area. We also observe potential active tectonic structures in the Axial Zone of the Pyrenees. These can be attributed to the accommodation of strain triggered by the exhumation of the Axial Zone of the Western Central Pyrenees. Finally, we propose an integrated strain model for the recent tectonic activity of the Western Central Pyrenees. In this area, the right-lateral transpression initiated by the oblique convergence between the Iberian and European plates is competing with vertical deformations triggered by the post tectonic surrection of the Axial Zone.