Geological map of the Monte Grighini Variscan Complex (Sardinia, Italy)

The study area, belongs to the Nappe zone of the Sardinian Variscan chain at the NW termination of the Flumendosa antiform. The Monte Grighini Complex is a NW-SE trending metamorphic complex made up of three tectonic units and synkinematic magmatic intrusions that show a section of the deepest portion of the Nappe zone. The tectonic units stacked and folded under lower greenschist and upper amphibolite facies conditions, were finally juxtaposed by a kilometer-wide NW-SE trending dextral transtensive shear zone during the Late Variscan tectonics. The 1:25,000 scale geological map, cross sections and shear zone deformation map illustrate the tectonic and metamorphic setting of the area, resulting from the polyphasic Variscan collisional evolution including early nappe stacking and later strike slip and extensional tectonics coeval with a late Carboniferous magmatism. Deformation structures and metamorphic assemblages recorded by the tectonic units as well as synkinematic intrusions, provide constraints of fundamental importance for the reconstruction of southern Variscan chain tectono-metamorphic history.