Metamorphic and structural analysis on Archean and Paleoproterozoic rocks from eastern Quadrilátero Ferrífero (mg)

Abstract

The geological history of the Quadrilátero Ferrífero (QF) records important episodes of early Earth evolution, including sedimentation and orogenesis processes from Archean and Paleoproterozoic, and further tectonic reworking during the Neoproterozoic. The understanding of superposed tectonic processes in polycyclic terranes requires detailed geological and structural surveys in order to set a hierarchy and characterize the different orogenetic phases. In the eastern part of the QF, especially in the vicinity of the Serra do Caraça, there are expositions of archean TTG rocks and supracrustal rocks from the Rio das Velhas Greenstone Belt, as well as paleoproterozoic siliciclastic sequences from Minas Supergroup. The structural framework of these rocks is related to the superposition of neoarchean, orosirian and ediacaran orogenies. The structural complexity and the lack of detailed metamorphic studies in this region have stimulated the present scientific initiation project that aims to contribute for the understanding of the evolutionary history of the QF. To achieve it, this project includes detailed geological and structural surveys in key areas of QF's eastern margin. These surveys will include the development of virtual outcrops and high-resolution digital terrain models utilizing unmanned aerial vehicles (UAV or drones). Metamorphic and geothermobarometric studies will be conducted in representative samples of the investigated areas aiming to constrain PT (pressure-temperature) conditions to the different orogenic phases of QF's evolution.