The iron formation of the Puga Formation: regional resources evaluation in the Serra da Bodoquena, Mato Grosso do Sul state

Author(s)

Thiago Piacentini

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Geociências (IG/BT)
• Defense date: 2009-03-16

Examining board members

Jorge Kazuo Yamamoto; Francisco Jose Fonseca Ferreira; Carlos Alberto Rosière

• Advisor: Jorge Kazuo Yamamoto

Abstract

Neoproterozoic iron formations are worldwide known and they are a very peculiar kind of deposit not only by economic aspects but also they are usually related to glacial deposits. This dissertation focus on iron formation associated with glaciogenic diamictites interpreted as belonging to the Puga Formation, in Bodoquena, state of Mato Grosso do Sul. To this deposit magnetic survey, geological mapping, geochemical and petrographical characterization, as well as iron resource evaluation have been done. Moreover, aeromagnetic data were effective to delineate the total iron formation coverage. Its mostly composed of fine disseminated iron oxide layers alternated with silica. Isolated blocks occur within the iron formation but tectonic overprinting makes it difficult to have a clear observation of the relationship between clasts and original lamination. The geological evidences observed show that the Puga Formation had a glacial contribution during its deposition, and probably is related to the Varanger/Mar inoan event. It may have deposited in a distal hydrothermal environment with the ferruginous fluid precipitation together with glacial sediments. The regional evaluation of Bodoquena resources through conventional methods shows that this region has geological resource potential for more than one billion tons of iron ore. Technological characterization tests results in 65% mass recovery w ith 55% Fe. This implies in products that attend to merchantable specifications. (AU)