La relación entre el metamorfismo y la deformación Varisca en el domo de La Pallaresa, sector central de la Zona Axial pirenaica

Abstract

The crystallization–deformation relationship and the microstructural analysis of metasedimentary rocks in the La Pallaresa Massif and the contact area with the Aston and Hospitalet gneissic domes have made it possible to identify two HT-LP metamorphic events and characterize their relationship with the Variscan deformation events in this sector of the Pyrenean Axial Zone. These metamorphic episodes are: (i) the first one, represented by low-grade mineral assemblages, which could occasionally reach medium–grade conditions, and is syntectonic with the first Variscan deformation event; (ii) the second episode presents medium–high–grade metamorphic mineral associations, it is the main one in this area, and coeval with the last Variscan deformation event. It is associated with an extensional event, which favoured magmatic intrusions during the last stages of the Variscan Orogeny.