Emplacement of Lavadores granite: AMS study

The AMS studies were done on magnetite type granite, the Lavadores granite which is an example of late to post-orogenic Varsican granite in Northern Portugal (NW Iberian Peninsula). The post tectonic emplacement is supported by the magmatic nature of the microstructures. In the northern region Magnetic lineations are sub-vertical and sub-horizontal in the southern region. Magnetic foliations display a general WNW-ESE sub-vertical pattern consistent with a dextral kinematic. These AMS data suggest that the emplacement of the Lavadores granite was controlled by a major mechanical anisotropy formed by trans-tensional structures associated with the Porto-Tomar shear zone.