CARACTERIZAÇÕES PETROGRÁFICA E GEOFÍSICA DAS UNIDADES LITOLÓGICAS DO MUNICÍPIO DE BANANAL, LESTE DO ESTADO DE SÃO PAULO, E CORRELAÇÃO COM OCORRÊNCIAS DE ILMENITA.

Petrographic and geophysical characterization of lithological units in the Municipality of Bananal, East of the São Paulo state, and correlation with ilmenite occurrences

Abstract

The mineral ilmenite (FeTiO₃) corresponds to one of the main containing Ti, and accounting for 90% of the world's consumption of this element. China and Australia hold 50% of the world's measured reserves of ilmenite. In Brazil, the main deposits are located in the municipalities of Mataraca (PB), São Francisco de Itabapoana and São João da Barra (RJ), all in a placer-type environment. Granites and pegmatites are important deposits of this element and, in the municipality of Bananal (SP), there are records of granites Bananal and Resgate units. The studies were carried out in three stages: integration of geological, aerogeophysical and geomorphological data; field campaigns, with the ilmenite being identified in five heavy concentrates; and chemical analysis of ilmenite grains by means of MEV, aiming at the qualitative identification of the mineral and its solid inclusions. The ilmenite grains had dimensions between 0.05mm and 2mm and chemical composition from 9.85% to 69.48% of Fe and 5.99% to 26.18% of Ti. The presence of ilmenite is associated with Resgate and Granito Bananal granite bodies. The geophysical signatures in both methods indicate heterogeneous mineral and chemical compositions along the granitic bodies.