Produção Nacional
Rochas charnockíticas do sudeste de Minas Gerais: a raiz granulítica do arco magmático do Orógeno Araçuaí
2010; Sociedade Brasileira de Geologia; Volume: 40; Issue: 4 Linguagem: Inglês
10.25249/0375-7536.2010404573592
ISSN2177-4382
AutoresTiago Amâncio Novo, Antônio Carlos Pedrosa Soares, Carlos Maurício Noce, Fernando F. Alkmim, Ivo Dussin,
Tópico(s)Geography and Environmental Studies
ResumoThe Araçuaí and Ribeira orogens are a Cambrian-Neoproterozoic belt that extends from the eastern edge of the San Francisco craton to the Atlantic Ocean, south of parallel 15 º. The connection between these orogens is roughly situated along the 21 º S parallel. High-grade metamorphic rocks are exposed in the southern Araçuaí Belt, SE Minas Gerais, reflecting a deep crustal level. The Divino Suite comprises mafic- to felsisc charnockites, metamorphosed in granulite facies, interpreted as an expanded calc-alkaline suite metaluminous to slightly peraluminous. Chemical and Nd isotopic signatures suggest the Divino Suite evolved in a continental magmatic-arc setting, and also that Paleoproterozoic basement was a major source for parental magmas. U-Pb dating of charnockite samples (592±7, and 603±4 Ma) indicates the suite is coeval with the pre-collisional stage of Araçuaí Orogen evolution, and probably represents the magmatic arc granulitic roots. The southward extent of this arc is of great importance in order to unveil the link between Araçuaí and Ribeira orogens.
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