Avaliação morfoscópica de sedimentos da bacia hidrográfica do Rio Santo Antônio – Serra da Canastra (MG)

Abstract

The sedimentary morphoscopy studies is an important tool to characterize grains of a given channel with studies of sphericity, roundness, and parental material, from their results, which can influence the relief sculpture. The purpose of this research is to understand the distribution and characterization of sediments collected in the Santo Antônio River Basin, located in the Serra da Canastra National Park – MG and surroundings, to evaluate the dynamics of sediment transport that occur in this space. Through textural analysis and the study of the genetics of the samples collected in the river channels, they are the result of dynamic processes that collaborate for the sculpting of the regional relief. These channels carry sediments, which were collected in a total of 51 points and, for each sampling point, 50 discontinuous grains with three different diameters were evaluated: 0.600mm; 0.850mm; 1.70mm. In all, 7,650 grains were evaluated, enabling the quali-quantification of the grains on their sphericity, roundness, and the lithological aspect of the material. From the analyzes carried out with the granulometry method by sieving and observation by a precision portable digital type magnifier, monocular, 1000x magnification with a 2.0-megapixel camera. The results point to a greater number of sediments with low sphericity, roundness of the very angular to angular type, with predominance of material of geological aspect such as quartz, laterite, and mica.