Métodos geofísicos aplicados ao ultramafito da Serra de Quatipuru - Estado do Pará

Abstract

The objective of the present work is the application of geophysical methods for the economical evaluation of Ni, Cr and asbestos occurrences in an area of 6.25 km2 - Malha 2 - in Sierra Quatipuru 50 km SW of Conceição do Araguaia, in the South of the State of Pará. Magnetic methods were applied initially for reconnaissance, using total and vertical field magnetometers, in order to locate anomalous zones of asbestos and cromite, associated with magnetite. The electromagnetic method of dip-angle was used to define conductive zonas associated with possible mineral deposits or structural features. Based on the interpretation of the magnetic and electromagnetic data several areas defined for the application of the induced polarization-resistivity method aiming at possible deposits of dissemineted sulphides as the main targets. The possible occurrences of mineral deposits in the area were correlated with the geophysical anomalies and were investigated further by drilling. It was concluded that occurrences do not have economic interest. However, the application of these geophysical methods was successful in the investigation of this problem as they have advantages over the more conventional methods which are expensive and time consuming.