Influence of regional lineaments on the morphology of the Mestre Álvaro Massif (Serra-ES)

Abstract

Geological and geomorphological analyzes are essential in the relief understanding, highlighting here the study of the structural influence on the morphology of the Mestre Álvaro Massif (Serra-ES). The origin of the massif is directly linked to events related to the Araçuaí Orogen, with emphasis on its final phase, when numerous post-tectonic granitic intrusions were generated. The data analyzed include lineaments extracted from different sources, in addition to information obtained from field work, which includes structural measurements of faults, fractures and mineralogical orientation, in addition to the identification of the constituent rocks of the massif and its main geomorphological features. Lineament analyzes indicate a clear predominance of features with orientations varying between NNW-SSE and NW-SE, with a secondary participation of lineaments with NE-SW orientation. Similarly, the orientations of porphyritic crystals in granitic rocks also follow the NNW-SSE to NW-SE directions. Fractures and failed veins were also found, with orientations also corresponding to those indicated for the lineaments and which are consistent with recent neotectonic studies in the area. The results thus indicate that the Colatina Lineament Bundle is the most important geological structure in shaping the relief of the Mestre Álvaro Massif, influencing the orientation of most of the valleys and ridges.