Palaeomagnetic study of Jurassic limestones from the Iberian Range (Spain): Tectonic implications

A palaeomagnetic investigation has been carried out in the Iberian Range (Spain). Seven localities have been sampled. Two stable magnetization components have been found in all investigated sections. A high-temperature primary component of Oxfordian age shows alternatively normal and reversed polarities. A consistent low-temperature component appears in all the studied sites; it has normal polarity and passes the fold test indicating its pre-Oligocene-Miocene age. Six localities show counterclockwise declinations for both components, the high-temperature component having a Jurassic direction and the low-temperature component an early Cretaceous direction. Only the southernmost section shows a clockwise rotation for both components. This indicates that the whole Iberian Range can not be considered as a part of Stable Iberia. The angular difference (c. 15°) between both components is the same in all investigated sites. This implies that: (1) based on the palaeomagnetic direction of both components, the low-temperature remagnetization was probably acquired in the Cretaceous during the rotation of the Iberian Plate; (2) the clockwise rotation observed in the southernmost section took place after the acquisition of the remagnetization.