Ocorrência de grafita na Faixa Araguaia, norte do estado do Tocantins, municípios de Xambioá e Araguanã

Abstract

This paper presents preliminary data from the Grafita Project in an area located in the Araguaia Foldbelt, Tocantins Province. Thirty new occurrences of graphite have been registered in the region comprising the municipalities of Xambioá-TO and Araguanã-TO, in the northern portion of the state of Tocantins, Brazil. A preliminary Geological and Mineral Resource Map was produced based on petrographic data. The regional metamorphism is in the medium-high amphibolite facies. Two kinds of occurrences were registered on the Neoproterozoic rocks of the Araguaia Foldbelt: one type is in the form of lenticular bodies found in the metasedimentary rocks of the Canto da Vazante Formation and the other type of occurrence is in the form of a layer occurring within rocks from a Metavolcanosedimentary Sequence that is believed to be correlated with the Quatipuru Complex. The occurrence at point ER06 is located on a hill that has approximately 200,000,000 tons of graphitic schist. In both types of occurrences, graphite is mainly as microcrystalline with occasional flakes ranging from 1 to about 2 mm.