GEOCHEMICAL SPREAD IN SÃO DOMINGOS HYDROGRAPHIC BASIN (RJ) CONTROLLED BY BASIN MORPHOLOGY

Abstract

The São Domingos hydrographic basin are located in Ribeira Belt where are strongly structured than conditioned the drain network. It is on Rio de Janeiro state northwest that is a main farming area, when occur relief changes from crop demand like a result of deforestation process to livestock and logging. Used metals concentration in stream sediments and basement rocks correlated was possible identify different influences in metals concentrations in these sediments, as well as spread geochemistry of that. It was observed than metals concentration (Cd, Co, Cr, Cu, Ni, Pb, Sr, V e Zn) are distributed in four morphostructural zones, also defined by network drain structuring and whose source was characterized like anthropic and natural source. Are an anthropic contribution up hydrographic basin however, the most main contribution is coming from basement rocks in the measured concentration and, that contribution is intensify by drain structuring.