The Além Paraíba-Pádua shear zone system (Southern Brazil) represents the northern termination of a transcurrent shear zone network that is located in the central part of the Araçuaí-Ribeira belt. It consists of high temperature (>800°C ) mylonitic segments with mainly N70E and N40E trends. The nucleation and the development of this system comprised the deformation of rocks at distinct crustal levels (granulites, migmatites and sintectonic granites) and, therefore, with different rheological competences. The main goal of this project is to investigate the mechanical behavior of these rocks during the nucleation of this shear zone system. Through the characterization of the main microstructures and deformation mechanisms recorded in these rocks (using the MEV-EBSD technique), we intend to examine the rheology of the continental crust during the orogenic evolution. Considering that the rheological behavior of the continental crust changes with depth in response to several factors (mineralogical composition of the rocks, temperature, pressure, viscosity, strain rate, etc), an additional thermal study (TitaniQ thermometry) plus viscosity estimates (using the Kware Magma software) will be performed to evaluate the temperature conditions and the rheology of the rocks during the orogenic deformation. The combination of the aforementioned techniques will contribute to understand the rheological behavior of the continental crust of the central region of the Araçuaí-Ribeira belt during the development of the Além Paraíba-Pádua shear zone system.
News published in Agência FAPESP Newsletter about the scholarship: