Aplicação de técnicas de processamento digital de imagens e classificação não supervisionada em dados aerogeofísicos: o exemplo do Greenstone Belt Rio das Velhas, Quadrilátero Ferrífero, MG

Abstract

A group of image-processing methods and an unsupervised classification were applied to the Rio das Velhas airborne geophysical data. The products show potential application to mineral exploration, because the enhancement improved the information content of the single geophysical channels. The images have been processed with various combinations. The best product was the analytical signal amplitude and phase integrated by IHS transformation. Information extracted maps the geology and lineament patterns at regional and local scales. The K-means technique was applied to the geophysical data and resulted in 10 classes. These classes show the lithologies mapped by the field geologists at the 1:100.000.