Metamorphic characterization of the Aguapeí Mobile Belt and it's relationship to the metallogenesis of gold deposits in Pontes e Lacerda region, Mato Grosso state.

Abstract

In Pontes e Lacerda region, Western of Mato Grosso state, there are a large number of gold deposits and mineral occurrences formed over a NNW - SSE mobile belt named Aguapeí Mobile Belt developed during Sunsás Orogeny (about 1,0 Ga). This region has been mined since 18th century by rudimentary methods but in recent years has become economically important due to operation start of two gold mines and the construction of other two. However there aren't enough number of scientific studies about metallogenesis of gold deposits and detailed scale geology. In this context, this research proposal aims to define the process responsible by deposits formation emphasizing the role of metamorphism as provider of fluid and energy to the mineralizing system, trying an approach of crustal process to metalogenetic studies of gold deposits whereas its features are similar to orogenical gold type. Therefore this research intends perform metamorphic studies over Aguapeí Mobile Belt and metallogenetic studies of two gold deposits (Ernesto and Pau-a-Pique), who were selected as case study because of their host rocks and structural context. The proposed methodology involves geological mapping at detailed scale, structural geology studies, followed by transmitted light petrography and in reflected light petrography of metamorphic rocks and ore minerals, chemical analysis of ore and metamorphic minerals to performing themobarometric calculations, fluid inclusions study, isotope geochemistry involving geochronology of metamorphic and mineralizing events as well as analysis of stable isotopes of hydrothermal alteration minerals. It's expected as result of the research a model of the metamorphic evolution to Aguapeí Mobile Belt with implications to gold metallogenesis.