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BIBTEX RIS

A SEQÜÊNCIA VULCANOSSEDIMENTAR DO GRUPO NOVA LIMA NA REGIÃO DE PIEDADE DO PARAOPEBA, BORDA OESTE DO QUADRILÁTERO FERRÍFERO, MINAS GERAIS

1992; Sociedade Brasileira de Geologia; Volume: 22; Issue: 2 Linguagem: Inglês

10.25249/0375-7536.1992175183

ISSN

2177-4382

Autores

CARLOS M. NOCE, STELAMARIS O. PINHEIRO, EDUARDO A. LADEIRA, CLÁUDIA R. FRANCA, SENIRA KATTAH,

Tópico(s)

Geochemistry and Geologic Mapping

Resumo

THE QUADRILÁTERO FERRÍFERO.Piedade do Paraopeba is located at western Quadrilátero Ferrifero, where a 15 km long tectonic slice of Nova Lima Group rocks are stacked between the gneissic rocks of the Bonfim Complex and the basal Minas Supergroup formation (the Moeda Quartzite).The southern part of the Nova Lima sequence consists of ultramafic and mafic metavolcanics with local preserved pillow structures, minor felsic metavolcanics, metachert and thin carbonate and oxide iron formation.This sequence grades northwards to an interlayered sequence of carbonaceous phyllites, quartz-mica schists, volcanoclastic metarenites, and iron formation.The metavolcanic rocks underwent intense metassomatic alteration.Chemical analyses show that the ultramafic rocks are probably former komatiitic peridotites while the upper mafic rocks are tholeitic basalts.A polyphasic structural evolution has been distinguished in the area.The main deformation phase (Dn) led to basal thrusts with a W-NW tectonic transport.

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