Paleomagnetic and inner diapiric structural constraints on the kinematic evolution of a salt-wall: The Bicorb-Quesa and northern Navarrés salt-wall segments case (Prebetic Zone, SE Iberia)

Paleomagnetism together with an analysis of the internal structure of the Bicorb-Quesa and northern Navarrés salt-wall segments (Prebetic Zone in SE Iberia) were used to constrain their kinematics and driving mechanisms. Paleomagnetic data from Upper Triassic red beds of the selected salt-related structures and from the Miocene rocks belonging to adjacent syn-diapiric half-grabens reveal 15-30° counter-clockwise vertical-axis rotations of the salt-wall rocks and a 20° clockwise rotation of the Jurassic-Miocene cover block located south of the salt-wall. This, together with the salt-wall structure, indicates that the origin of the salt-wall was linked to the motion of a late Miocene thin-skinned extensional fault system, which detached on the Upper Triassic evaporites. Specifically, the salt-wall formed by the south-southwest displacement with a 20° clockwise rotation component of a cover block bounded northwards by the detachment disruptions generated by the motion of pre-existent basement faults. The Upper Triassic detachment level was first affected by a counter-clockwise vertical axis rotation and, during the Paleogene-earliest Miocene building of the Iberian Chain, by tight WNW-trending folds and SSE-directed minor thrusts. This study also shows that Paleomagnetism together with the analysis of the internal structure can successfully depict the geometry and kinematic evolution of complex salt-wall structures.