Oceanic crust and mantle evidence for the evolution of Tonian-Cryogenian ophiolites, southern Brasiliano Orogen
Autor(a) principal: | |
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Data de Publicação: | 2020 |
Outros Autores: | , , , , , , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UFRGS |
Texto Completo: | http://hdl.handle.net/10183/220256 |
Resumo: | Unravelling the complexity of tonian-cryogenian (950–680 Ma) evolution of ophiolites requires the search for rare mineral systems and their quantification with varied techniques. Ophiolites in the Brasiliano Orogen are widely distributed over 2,000 km along the eastern half of South America. We selected two ophiolites from different geotectonic settings of the Sul-Riograndense Shield, southern Brasiliano Orogen, to delimit the evolution of the oceanic phase of the orogen. The southern portion of the Bossoroca ophiolite is inserted in the São Gabriel juvenile terrane and contains rare metasomatic tourmaline in chloritite close to serpentinite and metamorphosed Cr-spinel. The southern Bossoroca ophiolite was intruded by Cerro da Cria and Ramada Granites and the U-Pb-Hf isotopic study of zircon from these rocks constrains the crustal evolution of the São Gabriel juvenile terrane. Capané ophiolite has similar age (793–715 Ma) as the Bossoroca ophiolite and was inserted in the Porongos fold-thrust belt with preserved Cr-spinel of mantellic composition. Integrated use of Cr-spinel mineral chemistry, B isotopes in tourmaline in the Bossoroca ophiolite and zircon U-Pb-Hf isotopes of granites associated with the southern Bossoroca ophiolite revealed several steps in the evolution of the ophiolites in the Dom Feliciano Belt. Capané Cr-spinel cores have mantle-derived compositions (Mg# 0.66 – 0.69; Cr# 0.51 – 0.53), tourmaline from the Bossoroca ophiolite is dravite and has δ11B = 0 to + 3, and granites crystallization ages are 578 ± 3.2 and 612 ± 12 Ma (εHfzrn = −10 to −25). Zircon from other dravite occurrences of the Bossoroca ophiolite were previously dated at 920 Ma. We unraveled the main steps in the evolution of ophiolites from the southern Brasiliano Orogen, with emphasis on the Bossoroca and Capané ophiolites, during their trajectory from mid-ocean ridge (920 Ma), formation of dravite in oceanic crust, preservation of mantellic cores in Cr-spinel, and intrusion of craton-generated granites at 612–578 Ma. |
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Werle, MarianaHartmann, Léo AfraneoQueiroga, Gláucia NascimentoLana, Cristiano de CarvalhoPertille, JulianaMichelin, Cassiana Roberta LizzoniRemus, Marcus Vinicius DornelesRoberts, Malcolm PeterCastro, Marco Paulo deLeandro, Carolina GonçalvesSavian, Jairo Francisco2021-04-27T04:34:04Z20200301-9268http://hdl.handle.net/10183/220256001122697Unravelling the complexity of tonian-cryogenian (950–680 Ma) evolution of ophiolites requires the search for rare mineral systems and their quantification with varied techniques. Ophiolites in the Brasiliano Orogen are widely distributed over 2,000 km along the eastern half of South America. We selected two ophiolites from different geotectonic settings of the Sul-Riograndense Shield, southern Brasiliano Orogen, to delimit the evolution of the oceanic phase of the orogen. The southern portion of the Bossoroca ophiolite is inserted in the São Gabriel juvenile terrane and contains rare metasomatic tourmaline in chloritite close to serpentinite and metamorphosed Cr-spinel. The southern Bossoroca ophiolite was intruded by Cerro da Cria and Ramada Granites and the U-Pb-Hf isotopic study of zircon from these rocks constrains the crustal evolution of the São Gabriel juvenile terrane. Capané ophiolite has similar age (793–715 Ma) as the Bossoroca ophiolite and was inserted in the Porongos fold-thrust belt with preserved Cr-spinel of mantellic composition. Integrated use of Cr-spinel mineral chemistry, B isotopes in tourmaline in the Bossoroca ophiolite and zircon U-Pb-Hf isotopes of granites associated with the southern Bossoroca ophiolite revealed several steps in the evolution of the ophiolites in the Dom Feliciano Belt. Capané Cr-spinel cores have mantle-derived compositions (Mg# 0.66 – 0.69; Cr# 0.51 – 0.53), tourmaline from the Bossoroca ophiolite is dravite and has δ11B = 0 to + 3, and granites crystallization ages are 578 ± 3.2 and 612 ± 12 Ma (εHfzrn = −10 to −25). Zircon from other dravite occurrences of the Bossoroca ophiolite were previously dated at 920 Ma. We unraveled the main steps in the evolution of ophiolites from the southern Brasiliano Orogen, with emphasis on the Bossoroca and Capané ophiolites, during their trajectory from mid-ocean ridge (920 Ma), formation of dravite in oceanic crust, preservation of mantellic cores in Cr-spinel, and intrusion of craton-generated granites at 612–578 Ma.application/pdfengPrecambrian research, Amsterdam. Vol. 351, (Dec. 2020), e105979, 13 p.Ofiolito : Rio Grande do SulOfiolito : Tectonica oceanicaMetasomatic tourmalineMantle-derived Cr-spinelCrustal evolutionOceanic crust and mantle evidence for the evolution of Tonian-Cryogenian ophiolites, southern Brasiliano OrogenEstrangeiroinfo:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFRGSinstname:Universidade Federal do Rio Grande do Sul (UFRGS)instacron:UFRGSTEXT001122697.pdf.txt001122697.pdf.txtExtracted Texttext/plain0http://www.lume.ufrgs.br/bitstream/10183/220256/2/001122697.pdf.txtd41d8cd98f00b204e9800998ecf8427eMD52ORIGINAL001122697.pdfTexto completo (inglês)application/pdf16498550http://www.lume.ufrgs.br/bitstream/10183/220256/1/001122697.pdf1bf7eabbb6847dc81d6a7317f5a2c105MD5110183/2202562021-11-20 06:01:27.456271oai:www.lume.ufrgs.br:10183/220256Repositório de PublicaçõesPUBhttps://lume.ufrgs.br/oai/requestopendoar:2021-11-20T08:01:27Repositório Institucional da UFRGS - Universidade Federal do Rio Grande do Sul (UFRGS)false |
dc.title.pt_BR.fl_str_mv |
Oceanic crust and mantle evidence for the evolution of Tonian-Cryogenian ophiolites, southern Brasiliano Orogen |
title |
Oceanic crust and mantle evidence for the evolution of Tonian-Cryogenian ophiolites, southern Brasiliano Orogen |
spellingShingle |
Oceanic crust and mantle evidence for the evolution of Tonian-Cryogenian ophiolites, southern Brasiliano Orogen Werle, Mariana Ofiolito : Rio Grande do Sul Ofiolito : Tectonica oceanica Metasomatic tourmaline Mantle-derived Cr-spinel Crustal evolution |
title_short |
Oceanic crust and mantle evidence for the evolution of Tonian-Cryogenian ophiolites, southern Brasiliano Orogen |
title_full |
Oceanic crust and mantle evidence for the evolution of Tonian-Cryogenian ophiolites, southern Brasiliano Orogen |
title_fullStr |
Oceanic crust and mantle evidence for the evolution of Tonian-Cryogenian ophiolites, southern Brasiliano Orogen |
title_full_unstemmed |
Oceanic crust and mantle evidence for the evolution of Tonian-Cryogenian ophiolites, southern Brasiliano Orogen |
title_sort |
Oceanic crust and mantle evidence for the evolution of Tonian-Cryogenian ophiolites, southern Brasiliano Orogen |
author |
Werle, Mariana |
author_facet |
Werle, Mariana Hartmann, Léo Afraneo Queiroga, Gláucia Nascimento Lana, Cristiano de Carvalho Pertille, Juliana Michelin, Cassiana Roberta Lizzoni Remus, Marcus Vinicius Dorneles Roberts, Malcolm Peter Castro, Marco Paulo de Leandro, Carolina Gonçalves Savian, Jairo Francisco |
author_role |
author |
author2 |
Hartmann, Léo Afraneo Queiroga, Gláucia Nascimento Lana, Cristiano de Carvalho Pertille, Juliana Michelin, Cassiana Roberta Lizzoni Remus, Marcus Vinicius Dorneles Roberts, Malcolm Peter Castro, Marco Paulo de Leandro, Carolina Gonçalves Savian, Jairo Francisco |
author2_role |
author author author author author author author author author author |
dc.contributor.author.fl_str_mv |
Werle, Mariana Hartmann, Léo Afraneo Queiroga, Gláucia Nascimento Lana, Cristiano de Carvalho Pertille, Juliana Michelin, Cassiana Roberta Lizzoni Remus, Marcus Vinicius Dorneles Roberts, Malcolm Peter Castro, Marco Paulo de Leandro, Carolina Gonçalves Savian, Jairo Francisco |
dc.subject.por.fl_str_mv |
Ofiolito : Rio Grande do Sul Ofiolito : Tectonica oceanica |
topic |
Ofiolito : Rio Grande do Sul Ofiolito : Tectonica oceanica Metasomatic tourmaline Mantle-derived Cr-spinel Crustal evolution |
dc.subject.eng.fl_str_mv |
Metasomatic tourmaline Mantle-derived Cr-spinel Crustal evolution |
description |
Unravelling the complexity of tonian-cryogenian (950–680 Ma) evolution of ophiolites requires the search for rare mineral systems and their quantification with varied techniques. Ophiolites in the Brasiliano Orogen are widely distributed over 2,000 km along the eastern half of South America. We selected two ophiolites from different geotectonic settings of the Sul-Riograndense Shield, southern Brasiliano Orogen, to delimit the evolution of the oceanic phase of the orogen. The southern portion of the Bossoroca ophiolite is inserted in the São Gabriel juvenile terrane and contains rare metasomatic tourmaline in chloritite close to serpentinite and metamorphosed Cr-spinel. The southern Bossoroca ophiolite was intruded by Cerro da Cria and Ramada Granites and the U-Pb-Hf isotopic study of zircon from these rocks constrains the crustal evolution of the São Gabriel juvenile terrane. Capané ophiolite has similar age (793–715 Ma) as the Bossoroca ophiolite and was inserted in the Porongos fold-thrust belt with preserved Cr-spinel of mantellic composition. Integrated use of Cr-spinel mineral chemistry, B isotopes in tourmaline in the Bossoroca ophiolite and zircon U-Pb-Hf isotopes of granites associated with the southern Bossoroca ophiolite revealed several steps in the evolution of the ophiolites in the Dom Feliciano Belt. Capané Cr-spinel cores have mantle-derived compositions (Mg# 0.66 – 0.69; Cr# 0.51 – 0.53), tourmaline from the Bossoroca ophiolite is dravite and has δ11B = 0 to + 3, and granites crystallization ages are 578 ± 3.2 and 612 ± 12 Ma (εHfzrn = −10 to −25). Zircon from other dravite occurrences of the Bossoroca ophiolite were previously dated at 920 Ma. We unraveled the main steps in the evolution of ophiolites from the southern Brasiliano Orogen, with emphasis on the Bossoroca and Capané ophiolites, during their trajectory from mid-ocean ridge (920 Ma), formation of dravite in oceanic crust, preservation of mantellic cores in Cr-spinel, and intrusion of craton-generated granites at 612–578 Ma. |
publishDate |
2020 |
dc.date.issued.fl_str_mv |
2020 |
dc.date.accessioned.fl_str_mv |
2021-04-27T04:34:04Z |
dc.type.driver.fl_str_mv |
Estrangeiro 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://hdl.handle.net/10183/220256 |
dc.identifier.issn.pt_BR.fl_str_mv |
0301-9268 |
dc.identifier.nrb.pt_BR.fl_str_mv |
001122697 |
identifier_str_mv |
0301-9268 001122697 |
url |
http://hdl.handle.net/10183/220256 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.ispartof.pt_BR.fl_str_mv |
Precambrian research, Amsterdam. Vol. 351, (Dec. 2020), e105979, 13 p. |
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info:eu-repo/semantics/openAccess |
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openAccess |
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