STREAM MORPHOMETRIC THE NORTHERN PORTION OF THE SÃO PAULO STATE WESTERN PLATEAU, SOUTHEAST BRAZIL, APPLIED TO THE DETECTION OF NEOTECTONIC CRUSTAL DEFORMATIONS

Abstract

This proposal aims to perform a neotectonic regional analysis of the Northwestern portion of the State of São Paulo by applying stream morphometric techniques, remote sensing image interpretation, integration of geological and geomorphological data and field work. The study area accounts for about 40,000 km2 and has a substrate composed of Cretaceous rocks (Serra Geral Formation basalts and post-basalt sedimentary rocks pertained to the Santo Anastácio, Adamantina and Marília formations). Locally, the cretaceous substrate is covered by alluvial quaternary sediments colluvium aprons and thick regolith. The morphometric measures already taken should be completed in this project, based on 1:50.000 scale topographic maps. The interpretation of remote sensing satellite images, with assistance from the Global Mapper application, envisages the delimitation of the main morphostructural framework (e.g., thicker soil zones, more expressive alluvial deposits, chiefly dissected zones, possibly linked to uplifting tectonic blocks). The interpretation of satellite images will also take into account the presence of brittle elements (lineaments), which may indicate fault zones, fractures swarms, and possible structural block boundaries. Field work will seek to characterize in situ tectonic deformations and their consequent structures, structural style and, if possible, chronologic elements, with special attention to characterization of structural elements linked to neotectonic deformations that might represent sectors with differential morphotectonic behavior, controlling the action of erosion processes and the accumulation of young sedimentary deposits.