Geochemical characterization of metaultramafic and metamafic rocks from Pajeú-Paraiba Belt - Northeast Brazil
Autor(a) principal: | |
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Data de Publicação: | 2009 |
Outros Autores: | , , |
Tipo de documento: | Artigo |
Idioma: | por |
Título da fonte: | Anuário do Instituto de Geociências (Online) |
Texto Completo: | https://revistas.ufrj.br/index.php/aigeo/article/view/6791 |
Resumo: | Concordant lenses of high pressure metaultramafic and metamafic rocks are positioned in Paleoproterozoic migmatites and orthogneisses of the Pajeú-Paraíba belt, Borborema Province, northeast Brazil. The geochemical signature of theses eclogites facies rocks points to a tholeiitic basaltic composition related to an island arc evolution. They are probably associated with a enriched mantle source underlying a subduction zone. This mantelic source was melted and further underwent in-situ differentiation, producing as high-MgO as high-FeO-TiO2 rocks. Cumulatic pyroxenites could be residual product of this process. The high-FeO-TiO2 group seems to represent more differentiated member submits to crustal contamination event. Reported positive and negative gravimetric anomalies in these metaultramafic and metamafic rocks occurrence area suggest the presence of possible NE-SW to E-W continental collision zone in the Borborema Province. |
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Geochemical characterization of metaultramafic and metamafic rocks from Pajeú-Paraiba Belt - Northeast BrazilCaracterização geoquímica de rochas metamáficas e metaultramáficas da Faixa Pajeú-Paraíba, Província Borborema - NE BrasilConcordant lenses of high pressure metaultramafic and metamafic rocks are positioned in Paleoproterozoic migmatites and orthogneisses of the Pajeú-Paraíba belt, Borborema Province, northeast Brazil. The geochemical signature of theses eclogites facies rocks points to a tholeiitic basaltic composition related to an island arc evolution. They are probably associated with a enriched mantle source underlying a subduction zone. This mantelic source was melted and further underwent in-situ differentiation, producing as high-MgO as high-FeO-TiO2 rocks. Cumulatic pyroxenites could be residual product of this process. The high-FeO-TiO2 group seems to represent more differentiated member submits to crustal contamination event. Reported positive and negative gravimetric anomalies in these metaultramafic and metamafic rocks occurrence area suggest the presence of possible NE-SW to E-W continental collision zone in the Borborema Province.Rochas metamáficas e metaultramáficas submetidas a metamorfimo de alta pressão ocorrem como lentes concordantes em uma seqüência de migmatitos - ortognaisses de provável idade Paleoproterozóica, na Faixa de Dobramentos Pajeú-Paraíba, Província Borborema, NE do Brasil. As rochas metamáficas possuem composição basáltica toleítica com assinatura geoquímica de arcos oceânicos, provavelmente geradas a partir de uma mesma fonte, um manto enriquecido subjacente a uma zona de subducção, que sofreu diferenciação in-situ gerando rochas com altos teores em MgO deixando um resíduo piroxenítico e um grupo de alto FeO-TiO2 que poderia representar os membros mais diferenciados dessa associação, submetidos a um mais elevado grau de contaminação crustal. A associação dessas rochas com anomalias gravimétricas positivas-negativas sugerem a presença de uma zona de colisão continental com direção geral NE-SW a E-W na Província Borborema.Universidade Federal do Rio de Janeiro2009-06-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionapplication/pdfhttps://revistas.ufrj.br/index.php/aigeo/article/view/679110.11137/2009_1_46-61Anuário do Instituto de Geociências; Vol 32, No 1 (2009); 46-61Anuário do Instituto de Geociências; Vol 32, No 1 (2009); 46-611982-39080101-9759reponame:Anuário do Instituto de Geociências (Online)instname:Universidade Federal do Rio de Janeiro (UFRJ)instacron:UFRJporhttps://revistas.ufrj.br/index.php/aigeo/article/view/6791/5388Copyright (c) 2009 Anuário do Instituto de Geociênciashttp://creativecommons.org/licenses/by/4.0info:eu-repo/semantics/openAccessAlmeida, Cícera Neysi deGuimarães, Ignez de PinhoBeurlen, HartmutTopitsch, Werner2017-01-23T21:49:50Zoai:www.revistas.ufrj.br:article/6791Revistahttps://revistas.ufrj.br/index.php/aigeo/indexPUBhttps://revistas.ufrj.br/index.php/aigeo/oaianuario@igeo.ufrj.br||1982-39080101-9759opendoar:2017-01-23T21:49:50Anuário do Instituto de Geociências (Online) - Universidade Federal do Rio de Janeiro (UFRJ)false |
dc.title.none.fl_str_mv |
Geochemical characterization of metaultramafic and metamafic rocks from Pajeú-Paraiba Belt - Northeast Brazil Caracterização geoquímica de rochas metamáficas e metaultramáficas da Faixa Pajeú-Paraíba, Província Borborema - NE Brasil |
title |
Geochemical characterization of metaultramafic and metamafic rocks from Pajeú-Paraiba Belt - Northeast Brazil |
spellingShingle |
Geochemical characterization of metaultramafic and metamafic rocks from Pajeú-Paraiba Belt - Northeast Brazil Almeida, Cícera Neysi de |
title_short |
Geochemical characterization of metaultramafic and metamafic rocks from Pajeú-Paraiba Belt - Northeast Brazil |
title_full |
Geochemical characterization of metaultramafic and metamafic rocks from Pajeú-Paraiba Belt - Northeast Brazil |
title_fullStr |
Geochemical characterization of metaultramafic and metamafic rocks from Pajeú-Paraiba Belt - Northeast Brazil |
title_full_unstemmed |
Geochemical characterization of metaultramafic and metamafic rocks from Pajeú-Paraiba Belt - Northeast Brazil |
title_sort |
Geochemical characterization of metaultramafic and metamafic rocks from Pajeú-Paraiba Belt - Northeast Brazil |
author |
Almeida, Cícera Neysi de |
author_facet |
Almeida, Cícera Neysi de Guimarães, Ignez de Pinho Beurlen, Hartmut Topitsch, Werner |
author_role |
author |
author2 |
Guimarães, Ignez de Pinho Beurlen, Hartmut Topitsch, Werner |
author2_role |
author author author |
dc.contributor.author.fl_str_mv |
Almeida, Cícera Neysi de Guimarães, Ignez de Pinho Beurlen, Hartmut Topitsch, Werner |
description |
Concordant lenses of high pressure metaultramafic and metamafic rocks are positioned in Paleoproterozoic migmatites and orthogneisses of the Pajeú-Paraíba belt, Borborema Province, northeast Brazil. The geochemical signature of theses eclogites facies rocks points to a tholeiitic basaltic composition related to an island arc evolution. They are probably associated with a enriched mantle source underlying a subduction zone. This mantelic source was melted and further underwent in-situ differentiation, producing as high-MgO as high-FeO-TiO2 rocks. Cumulatic pyroxenites could be residual product of this process. The high-FeO-TiO2 group seems to represent more differentiated member submits to crustal contamination event. Reported positive and negative gravimetric anomalies in these metaultramafic and metamafic rocks occurrence area suggest the presence of possible NE-SW to E-W continental collision zone in the Borborema Province. |
publishDate |
2009 |
dc.date.none.fl_str_mv |
2009-06-01 |
dc.type.none.fl_str_mv |
|
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
https://revistas.ufrj.br/index.php/aigeo/article/view/6791 10.11137/2009_1_46-61 |
url |
https://revistas.ufrj.br/index.php/aigeo/article/view/6791 |
identifier_str_mv |
10.11137/2009_1_46-61 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.relation.none.fl_str_mv |
https://revistas.ufrj.br/index.php/aigeo/article/view/6791/5388 |
dc.rights.driver.fl_str_mv |
Copyright (c) 2009 Anuário do Instituto de Geociências http://creativecommons.org/licenses/by/4.0 info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
Copyright (c) 2009 Anuário do Instituto de Geociências http://creativecommons.org/licenses/by/4.0 |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Universidade Federal do Rio de Janeiro |
publisher.none.fl_str_mv |
Universidade Federal do Rio de Janeiro |
dc.source.none.fl_str_mv |
Anuário do Instituto de Geociências; Vol 32, No 1 (2009); 46-61 Anuário do Instituto de Geociências; Vol 32, No 1 (2009); 46-61 1982-3908 0101-9759 reponame:Anuário do Instituto de Geociências (Online) instname:Universidade Federal do Rio de Janeiro (UFRJ) instacron:UFRJ |
instname_str |
Universidade Federal do Rio de Janeiro (UFRJ) |
instacron_str |
UFRJ |
institution |
UFRJ |
reponame_str |
Anuário do Instituto de Geociências (Online) |
collection |
Anuário do Instituto de Geociências (Online) |
repository.name.fl_str_mv |
Anuário do Instituto de Geociências (Online) - Universidade Federal do Rio de Janeiro (UFRJ) |
repository.mail.fl_str_mv |
anuario@igeo.ufrj.br|| |
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1797053538605465600 |