New and revisited paleomagnetic data from Permian–Triassic red beds: two kinematic domains in the west-central Pyrenees

New paleomagnetic results of Permian–Triassic red beds from Bielsa, Aure and Somport-Anayet sectors in thePyrenean Axial Zone are presented and combined with revisited and reviewed paleomagnetic data from thewest-central Pyrenees. The paleomagnetic data from the red beds vary between different sectors that sharesimilar structural position; i.e. whilst all sectors share the existence of a characteristic prefolding component,a Cenozoic postfolding component is found only in one area but not in other areas with similar structural po-sition and kinematics. Previous paleomagnetic data to the west of the studied zone reveal a pre-Turonianremagnetization component, but this secondary component is not found in an area that shares a similarstructural position (Aure). This variability suggests that the paleomagnetic behavior is the result of a seriesof factors related to the particular tectonic history of the region (sedimentation, burial, and deformation dur-ing basin inversion) and therefore paleomagnetic data demands careful assessment in order to unravel thekinematics of areas with equivalent structural positions in orogens.However, important kinematic implications that hold in the Pyrenees can be inferred from the restoration ofthe Permian–Triassic characteristic magnetizations to positions previous to the paleomagnetic rotationsrecorded by Cretaceous or Cenozoic paleomagnetic data. The restoration reveals on one hand the lack oflarge rotations in the South Pyrenenan Zone except in the Nogueras area, according to Bates (1989), andon the other hand, the contrasting rotations recorded to the west of the studied zone, in the Paleozoic BasqueMassifs (PBM) and the South-Pyrenean Zone, indicating the existence of two different tectonic domains inthe west-central sector of the Pyrenees. The strong clockwise rotations postdating the Early Cretaceousremagnetization that are recorded in the PBM and in the North Pyreneean Zone, suggest a late dextralshear deformation affecting areas near the North Pyrenean Fault ZoneÁrea de Geodinámica Interna, Universidad de Zaragoza, EspañaUnidad de Zaragoza, Área de Geología y Geofísica del Subsuelo, Instituto Geológico y Minero de España, EspañaUnidad de Zaragoza, Área de Cambio Global, Instituto Geológico y Minero de España, EspañaDepartment of Geological Sciences, University of Michigan, Estados UnidosDepartment Angewandte Geowissenschaften und Geophysik, Montanuniversität Leoben, Austri