U-Pb evidence for late Neoarchean crustal reworking in the Southern São Francisco Craton (Minas Gerais, Brazil)
Autor(a) principal: | |
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Data de Publicação: | 2003 |
Outros Autores: | , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Anais da Academia Brasileira de Ciências (Online) |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652003000400008 |
Resumo: | 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 metamorphism. For the leucosome, the upper intercept of discordia at 2599 ± 45 Ma corresponds to migmatization and granitoid genesis. Contemporaneous metamorphism and magmatism have been documented elsewhere in the São Francisco Craton, especially in the southern portion, demonstrating vast and vigorous reworking of sialic crust by the end of the Neoarchean. |
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U-Pb evidence for late Neoarchean crustal reworking in the Southern São Francisco Craton (Minas Gerais, Brazil)cratonArcheanmetamorphic complexU-Pb geochronologytectonic evolutionBrazilThe 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 metamorphism. For the leucosome, the upper intercept of discordia at 2599 ± 45 Ma corresponds to migmatization and granitoid genesis. Contemporaneous metamorphism and magmatism have been documented elsewhere in the São Francisco Craton, especially in the southern portion, demonstrating vast and vigorous reworking of sialic crust by the end of the Neoarchean.Academia Brasileira de Ciências2003-12-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652003000400008Anais da Academia Brasileira de Ciências v.75 n.4 2003reponame:Anais da Academia Brasileira de Ciências (Online)instname:Academia Brasileira de Ciências (ABC)instacron:ABC10.1590/S0001-37652003000400008info:eu-repo/semantics/openAccessCampos,José C.S.Carneiro,Maurício A.Basei,Miguel A.S.eng2003-11-04T00:00:00Zoai:scielo:S0001-37652003000400008Revistahttp://www.scielo.br/aabchttps://old.scielo.br/oai/scielo-oai.php||aabc@abc.org.br1678-26900001-3765opendoar:2003-11-04T00:00Anais da Academia Brasileira de Ciências (Online) - Academia Brasileira de Ciências (ABC)false |
dc.title.none.fl_str_mv |
U-Pb evidence for late Neoarchean crustal reworking in the Southern São Francisco Craton (Minas Gerais, Brazil) |
title |
U-Pb evidence for late Neoarchean crustal reworking in the Southern São Francisco Craton (Minas Gerais, Brazil) |
spellingShingle |
U-Pb evidence for late Neoarchean crustal reworking in the Southern São Francisco Craton (Minas Gerais, Brazil) Campos,José C.S. craton Archean metamorphic complex U-Pb geochronology tectonic evolution Brazil |
title_short |
U-Pb evidence for late Neoarchean crustal reworking in the Southern São Francisco Craton (Minas Gerais, Brazil) |
title_full |
U-Pb evidence for late Neoarchean crustal reworking in the Southern São Francisco Craton (Minas Gerais, Brazil) |
title_fullStr |
U-Pb evidence for late Neoarchean crustal reworking in the Southern São Francisco Craton (Minas Gerais, Brazil) |
title_full_unstemmed |
U-Pb evidence for late Neoarchean crustal reworking in the Southern São Francisco Craton (Minas Gerais, Brazil) |
title_sort |
U-Pb evidence for late Neoarchean crustal reworking in the Southern São Francisco Craton (Minas Gerais, Brazil) |
author |
Campos,José C.S. |
author_facet |
Campos,José C.S. Carneiro,Maurício A. Basei,Miguel A.S. |
author_role |
author |
author2 |
Carneiro,Maurício A. Basei,Miguel A.S. |
author2_role |
author author |
dc.contributor.author.fl_str_mv |
Campos,José C.S. Carneiro,Maurício A. Basei,Miguel A.S. |
dc.subject.por.fl_str_mv |
craton Archean metamorphic complex U-Pb geochronology tectonic evolution Brazil |
topic |
craton Archean metamorphic complex U-Pb geochronology tectonic evolution Brazil |
description |
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 metamorphism. For the leucosome, the upper intercept of discordia at 2599 ± 45 Ma corresponds to migmatization and granitoid genesis. Contemporaneous metamorphism and magmatism have been documented elsewhere in the São Francisco Craton, especially in the southern portion, demonstrating vast and vigorous reworking of sialic crust by the end of the Neoarchean. |
publishDate |
2003 |
dc.date.none.fl_str_mv |
2003-12-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652003000400008 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652003000400008 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S0001-37652003000400008 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
dc.publisher.none.fl_str_mv |
Academia Brasileira de Ciências |
publisher.none.fl_str_mv |
Academia Brasileira de Ciências |
dc.source.none.fl_str_mv |
Anais da Academia Brasileira de Ciências v.75 n.4 2003 reponame:Anais da Academia Brasileira de Ciências (Online) instname:Academia Brasileira de Ciências (ABC) instacron:ABC |
instname_str |
Academia Brasileira de Ciências (ABC) |
instacron_str |
ABC |
institution |
ABC |
reponame_str |
Anais da Academia Brasileira de Ciências (Online) |
collection |
Anais da Academia Brasileira de Ciências (Online) |
repository.name.fl_str_mv |
Anais da Academia Brasileira de Ciências (Online) - Academia Brasileira de Ciências (ABC) |
repository.mail.fl_str_mv |
||aabc@abc.org.br |
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1754302855848656896 |