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	Provedor de dados Anais da ABC (AABC) (2) Autor Basei,Miguel A.S. (1) CARNEIRO,MAURÍCIO A. (1) Campos,José C.S. (1) Carneiro,Maurício A. (1) OLIVEIRA,ARILDO H. (1) Palavra-chave Archean (2) Craton (2) Metamorphic complex (2) Tectonic evolution (2) Brazil (1) Lithodemic units (1) U-Pb geochronology (1) Mais... Tipo do documento Info:eu-repo/semantics/article (2) Ano 2003 (1) 2001 (1) País Brazil (2) Idioma Inglês (2)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 2 Primeira ... 1 ... Última U-Pb evidence for late Neoarchean crustal reworking in the Southern São Francisco Craton (Minas Gerais, Brazil) Anais da ABC (AABC) Campos,José C.S.; Carneiro,Maurício A.; Basei,Miguel A.S.. The Passa Tempo Metamorphic Complex is one of several metamorphic complexes that form the Archean sialic crust of the southern São Francisco Craton. It encompasses hypersthene-bearing gneissic rocks, with subordinateNW- or EW-trending mafic-ultramafic bodies and granodioritic to alkali-granitic, weakly foliated, and light-colored granitoids. These granitoids are the product of generalized migmatization that followed granulite-facies metamorphism. To determine the ages of the granulite-facies metamorphism and granitoid genesis, we obtained U-Pb ages on zircon extracted from the mesosome and leucosome of the migmatitic gneisses. For the mesosome, a discordia that intercepts Concordia at 2622 ± 18 Ma is interpreted as a minimum age for granulite-facies... Tipo: Info:eu-repo/semantics/article Palavras-chave: Craton; Archean; Metamorphic complex; U-Pb geochronology; Tectonic evolution; Brazil. Ano: 2003 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652003000400008 Campo Belo Metamorphic Complex: tectonic evolution of an Archean sialic crust of the southern São Francisco Craton in Minas Gerais (Brazil) Anais da ABC (AABC) OLIVEIRA,ARILDO H.; CARNEIRO,MAURÍCIO A.. Systematic geological studies performed in the study area allowed the characterization of six lithodemic units: three gneissic, one amphibolitic, one supracrustal and one fissure mafic. The mineral assemblage and the structural record of these lithodemic units indicate that the study area was affected by five tectonothermal events. The structural pattern of the first and oldest event occurred under granulite facies conditions and reveals essentially a sinistral kinematic pattern. The second event, showing dominant extensional characteristics, is related to the generation of an ensialic basin filled by the volcano-sedimentary sequence of the supracrustal lithodemic unit. The third event, which is the most expressive in the study region, is characterized by... Tipo: Info:eu-repo/semantics/article Palavras-chave: Craton; Archean; Tectonic evolution; Lithodemic units; Metamorphic complex. Ano: 2001 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652001000300009 Registros recuperados: 2 Primeira ... 1 ... Última

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