Investigação de estruturas rúpteis em uma porção do Complexo Granítico Caçapava do Sul e áreas adjacentes

Abstract

The structural analysis allows understanding the tectonic events and understanding the processes of deformation of the rocks over time. The deformation processes generate structures in the rocks depending on conditions such as temperature, pressure, time, elasticity, plasticity, rupture strength and burial depth. The present work presents a structural geology study of an area located in the Caçapava do Sul Granite Complex, focused on the brittle structures that affected this unit. Ruptured structures were characterized by lineaments seen in satellite images and aerial photographs, as well as fractures seen and interpreted in an outcropping scale, in which a main NW-SE direction, a possible fault, was investigated in this study. The main objective of this work was to obtain structural data of these lineaments and to characterize them through the integration of remote sensing data and field work with structural data collection, in view of the type of structures and regime of brittle deformation that they suffered. The lineaments demarcated by satellite images have preferred directions NW-SE and NNW-SSE. In this study, diabase dikes were found to be concordant with these directions. From the data studied in the field, together with information from the literature, it can be said that there is no considerable displacement in the study lineaments, and that if this is a transcurrent fault, there is little lateral displacement; being possible that the displacement is more vertical than lateral. There is evidence that the NW-SE lineament occurred after the NE-SW lineament that intercepts it and there is a hypothesis that this (NW) is related to structures of the Rio Grande Arc.