Evaluating the discrimination of Cu-mineralized rock alteration products from simulated MAPSAR Images in the Curaçá Valley, Brazil
Abstract:L-band images simulating MAPSAR satellite sensor data were used to identify Cu-mineralized rock alteration products in the Curaçá Valley, Brazil. The area is characterized by a semi-arid terrain, with residual soils and xerophytic vegetation. The mineralizations are mainly associated with pyroxenites but are also found in norites, gabbro-norites, and anorthosites. These mafic-ultramafic rocks produce characteristic Vertisols. A quantitative analysis for the rock discrimination was based on JM distances derived from training samples (amplitude values of L-HH, L-VV, and L-HV). The investigation showed the possibility of the discrimination of ore-bearing intrusives from the host rocks, with the exception of amphibolite. Variations in the surface moisture affected the SAR responses, prior to the data acquisition, and caused the higher returns created by wet Vertisols, favouring the discrimination of the rock alteration products.
Document Type: Research Article
Affiliations: INPE (National Institute for Space Research), São José dos Campos, São Paulo, Brazil
Publication date: 2007-01-01