Prospecção geofísica em ocorrência de cobre localizada na bacia sedimentar do Camaquã (RS)

Abstract

Mineral research studies are fundamental for the recognition and incorporation of new reserves. This paper presents the results of an application of the Electrical Resistivity geophysical method to a mineral occurrence of copper carbonates, by an electrical profiling technique in an azimutal array. The parameter of physical electric resistivity was measured, using the Electrical Resistivity method and the technique of electrical profiling. This study area is inserted in the Camaquã sedimentary basin, formed by sedimentary and volcanogenic stratigraphy units, where several copper occurrences are encountered. The presence of azurite and malachite in the fractures and high porosity zones in arenitic hosts define the local geology. The inversion models reveal circular anomalies of moderate resistivity up to 25m below the outcropping surface, and anomalies of low resistivity for depths below 25m, besides adjacent areas with high resistivity. Mineralization indicators described for the copper occurence in the Camaquã sedimentary basin are encountered in previous studies as well as the area now studied and allow for characterization in terms of electrical resistivivity. Silicified areas present high resistivity, while intermediary values are attributed to carbonated zones, and finally, low resistivity areas probably indicate concentrations of disseminated sulfites.