Orogenic magmatic events and their relations with the Nova Venécia complex in the southeastern sector of the Araçuaí orogen, Brazil
Autor(a) principal: | |
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Data de Publicação: | 2023 |
Tipo de documento: | Tese |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UFMG |
Texto Completo: | http://hdl.handle.net/1843/60874 |
Resumo: | The Araçuaí – West Congo Orogenic System constitutes a confined orogen to a large sheath of the São Francisco – Congo Craton, amalgamated into the Gondwana Paleocontinent at the end of the Neoproterozoic. A long-lasting succession of granite production events (ca. 630 – 480 Ma) associated to the orogenic stages is a remarkable feature of the Araçuaí orogen. Located in the easternmost sector, the study area includes rocks of pre-, sin-, and post-collisional orogenic stage intruded in the Nova Venécia migmatitic paragneisses, interpreted as an arc-related basin. The new petrological investigation, bulk-rock chemistry, and isotopic analyses (zircon U-Th-Pb and Lu-Hf by LA-ICPMS, and whole-rock Sm-Nd) were carried out in representative rocks from the orogenic magmatism and the Nova Venécia complex. In this context, Santa Tereza and Jequitibá suites represent the more eastern expression of pre-collisional magmatism associated with the Rio Doce magmatic arc, while Ataléia suite represent the syn-collisional rocks, and the Aracê – Pedra Azul, Vitória, and Mestre Álvaro plutons record the post-collisional event. The Santa Tereza and Jequitibá suites yield a concordant age of 612 ± 3 Ma and 594 ± 3 Ma, respectively. Their isotopic data represent the least evolved magmatism record in this orogen (Santa Tereza suite: εHf(612) of +2.3 to -4.8 with TDM of 1.33 to 1.65 Ga and εNd(612Ma) of -0.06 to -7.05 with TDM of 1.4 a 2.04; Jequitibá suite: εHf(594) of -1.7 to -36.4 with TDM of 1.33 to 3.21 Ga and εNd(594) of -6.67 to -8.8 with TDM of 1.64 to 1.87). These suites consist of I-type intermediate to acid intrusions, metaluminous to slightly peraluminous, mainly magnesian and calcic to alkali-calcic compositions, with portions of Opx-bearing and subordinate gabbroic rocks. Data from the S-type Ataléia granite (583 ± 3 Ma; εHf(t) -3.2 to -8.1, TDM ages from 1.42 to 1.64 Ga) and Nova Venécia migmatitic paragneisses (582 ± 7 to 2363 ± 26 Ma - with age peaks at 617 ± 4 Ma (68%), 719 ± 22 Ma (14%), 839 ± 46 Ma (8%), and 922 ± 31 Ma (10%); εHf(t) +4.1 to -39.2, TDM ages from 1.20 to 3.47 Ga) suggest the proximity of the Nova Venécia basin to the continental margin and that this basin received significant sediment from the Rio Doce magmatic arc. Furthermore, the dataset for the post-collisional intrusions (Aracê – Pedra Azul pluton: 523 ± 2 Ma, εHf(t) -18.6 to -23.8, TDM ages from 2.25 to 2.47 Ga; Vitória pluton: 505 ± 1 Ma, εHf(t) -7.4 to -10.3, TDM ages from 1.58 to 1.71 Ga; Mestre Álvaro pluton: 527 ± 2 Ma, εHf(t) -0.7 to -8.8, TDM ages from 1.27 to 1.66 Ga) indicates magma hybridization at high temperature, involving country rocks in the petrogenesis of post-collisional intrusions. The rocks studied reflect a crustal section composed of I-type intermediate to acid intrusions, S-type metagranites, and paragneiss framework rocks metamorphosed under amphibolite to granulite facies, commonly migmatized. Compared to a wide compiled dataset, our data suggest that a magmatic arc is likely to have developed in the region with an initial extensional phase followed by a compressional phase and an arc migration westward. |
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Antônio Carlos Pedrosa Soareshttp://lattes.cnpq.br/0388600397612432Mahyra Ferreira TedeschiAntônio Carlos Pedrosa SoaresTiago Amâncio NovoValderez Pinto FerreiraMoacir José Buenano MacambiraCaroline Cibele Vieira Soareshttp://lattes.cnpq.br/5662871155839581Cristina Santos Araujo2023-11-13T17:14:48Z2023-11-13T17:14:48Z2023-05-11http://hdl.handle.net/1843/60874The Araçuaí – West Congo Orogenic System constitutes a confined orogen to a large sheath of the São Francisco – Congo Craton, amalgamated into the Gondwana Paleocontinent at the end of the Neoproterozoic. A long-lasting succession of granite production events (ca. 630 – 480 Ma) associated to the orogenic stages is a remarkable feature of the Araçuaí orogen. Located in the easternmost sector, the study area includes rocks of pre-, sin-, and post-collisional orogenic stage intruded in the Nova Venécia migmatitic paragneisses, interpreted as an arc-related basin. The new petrological investigation, bulk-rock chemistry, and isotopic analyses (zircon U-Th-Pb and Lu-Hf by LA-ICPMS, and whole-rock Sm-Nd) were carried out in representative rocks from the orogenic magmatism and the Nova Venécia complex. In this context, Santa Tereza and Jequitibá suites represent the more eastern expression of pre-collisional magmatism associated with the Rio Doce magmatic arc, while Ataléia suite represent the syn-collisional rocks, and the Aracê – Pedra Azul, Vitória, and Mestre Álvaro plutons record the post-collisional event. The Santa Tereza and Jequitibá suites yield a concordant age of 612 ± 3 Ma and 594 ± 3 Ma, respectively. Their isotopic data represent the least evolved magmatism record in this orogen (Santa Tereza suite: εHf(612) of +2.3 to -4.8 with TDM of 1.33 to 1.65 Ga and εNd(612Ma) of -0.06 to -7.05 with TDM of 1.4 a 2.04; Jequitibá suite: εHf(594) of -1.7 to -36.4 with TDM of 1.33 to 3.21 Ga and εNd(594) of -6.67 to -8.8 with TDM of 1.64 to 1.87). These suites consist of I-type intermediate to acid intrusions, metaluminous to slightly peraluminous, mainly magnesian and calcic to alkali-calcic compositions, with portions of Opx-bearing and subordinate gabbroic rocks. Data from the S-type Ataléia granite (583 ± 3 Ma; εHf(t) -3.2 to -8.1, TDM ages from 1.42 to 1.64 Ga) and Nova Venécia migmatitic paragneisses (582 ± 7 to 2363 ± 26 Ma - with age peaks at 617 ± 4 Ma (68%), 719 ± 22 Ma (14%), 839 ± 46 Ma (8%), and 922 ± 31 Ma (10%); εHf(t) +4.1 to -39.2, TDM ages from 1.20 to 3.47 Ga) suggest the proximity of the Nova Venécia basin to the continental margin and that this basin received significant sediment from the Rio Doce magmatic arc. Furthermore, the dataset for the post-collisional intrusions (Aracê – Pedra Azul pluton: 523 ± 2 Ma, εHf(t) -18.6 to -23.8, TDM ages from 2.25 to 2.47 Ga; Vitória pluton: 505 ± 1 Ma, εHf(t) -7.4 to -10.3, TDM ages from 1.58 to 1.71 Ga; Mestre Álvaro pluton: 527 ± 2 Ma, εHf(t) -0.7 to -8.8, TDM ages from 1.27 to 1.66 Ga) indicates magma hybridization at high temperature, involving country rocks in the petrogenesis of post-collisional intrusions. The rocks studied reflect a crustal section composed of I-type intermediate to acid intrusions, S-type metagranites, and paragneiss framework rocks metamorphosed under amphibolite to granulite facies, commonly migmatized. Compared to a wide compiled dataset, our data suggest that a magmatic arc is likely to have developed in the region with an initial extensional phase followed by a compressional phase and an arc migration westward.O Sistema Orogênico Araçuaí – Congo Ocidental constitui um orógeno confinado a um grande embainhamento do Cráton São Francisco – Congo, amalgamados no Paleocontinente Gondwana ao final do Neoproterozoico. Uma das características mais marcantes do orógeno Araçuaí é a longa sucessão de eventos magmáticos (ca. 630 - 480 Ma) associados aos estágios orogênicos. Localizada a extremo leste deste orógeno, a área em estudo inclui rochas dos estágios orogenéticos pré-, sin- e pós-colisionais que intrudem em migmatitos paragnáissicos do Complexo Nova Venécia, interpretada como representante da bacia de retroarco. Nova investigação petrológica, de química de rocha total e análises isotópicas (U-Th-Pb e Lu-Hf por LA-ICPMS em zircão e Sm-Nd em rocha total) foram realizadas em rochas desses estágios e em rochas do complexo Nova Venécia. Nesse contexto, as suítes Santa Tereza e Jequitibá representam a expressão mais oriental do magmatismo pré-colisional associado ao Arco Magmático Rio Doce, enquanto as rochas da suíte Ataléia representam o estágio sin-colisional e os plútons Aracê – Pedra Azul, Vitória e Mestre Álvaro registram o magmatismo pós-colisional. Com uma idade Concórdia de 612 ± 3 Ma para a suíte Santa Tereza e 594 ± 3 Ma para a suíte Jequitibá, os isotópicos representam o registro de magmatismo pré-colisional menos isotopicamente envolvido neste orógeno (suíte Santa Tereza: εHf(612) de +2,3 a -4,8 com TDM de 1,33 a 1,65 Ga e εNd(612Ma) de -0,06 a -7,05 com TDM de 1,4 a 2,04; suíte Jequitibá: εHf(t) de -1,7 a -36,4 com TDM de 1,33 a 3,21 Ga e εNd(594) de -6,67 a -8,8 com TDM de 1,64 a 1,87). Essas suítes consistem em intrusões do tipo I, intermediárias a ácidas, metaluminosas a levemente peraluminosas, com composições principalmente magnesianas e cálcicas a alcalino-cálcicas, com porções de rochas contendo ortopiroxênio e rochas gabroicas subordinadas. Os dados do granito Ataléia (583 ± 3 Ma; εHf(t) de -3,2 a -8,1, TDM de 1,42 a 1,64 Ga) e dos paragnaisses migmatíticos do complexo Nova Venécia (582 ± 7 a 2363 ± 26 Ma – com picos de idades em 617 ± 4 Ma (68%), 719 ± 22 Ma (14%), 839 ± 46 Ma (8%) e 922 ± 31 Ma (10%); εHf(t) de +4,1 a -39,2, TDM de 1,20 a 3,47 Ga) sugerem proximidade da bacia retroarco à margem continental e que essa bacia recebeu significativa quantidade de sedimentos do Arco Magmático Rio Doce. Além disso, dados das rochas pós-colisionais na área (Aracê – Pedra Azul: 523 ± 2 Ma, εHf(t) de -18,6 a -23,8, TDM de 2,25 a 2,47 Ga; Vitória: 505 ± 1 Ma, εHf(t) de -7,4 a -10,3, TDM de 1,58 a 1,71 Ga; Mestre Álvaro: 527 ± 2 Ma, εHf(t) de -0,7 a -8,8, TDM de 1,27 a 1,66 Ga) indicam hibridização à altas temperaturas envolvendo as rochas encaixantes na petrogênese pós-colisional. As rochas estudadas refletem uma seção crustal composta de intrusões intermediárias a ácidas do tipo I, metagranitos do tipo S e rochas paragnaisses metamorfisados sob fácies anfibolito a granulito, comumente migmatizadas. Os resultados, comparados com uma vasta compilação bibliográfica, sugerem que um arco magmático provavelmente se desenvolveu na região com uma fase inicial extensional seguida por uma fase compressional e migração do arco para oeste.CNPq - Conselho Nacional de Desenvolvimento Científico e TecnológicoCAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorengUniversidade Federal de Minas GeraisPrograma de Pós-Graduação em GeologiaUFMGBrasilIGC - INSTITUTO DE GEOCIENCIAShttp://creativecommons.org/licenses/by-nc-nd/3.0/pt/info:eu-repo/semantics/openAccessTempo geológicoIsótoposMagmatismo – BrasilU-Pb geochronologyHf-Nd isotopesSlab retreatActive marginBrasiliano orogenyOrogenic magmatismAraçuaí orogenOrogenic magmatic events and their relations with the Nova Venécia complex in the southeastern sector of the Araçuaí orogen, BrazilMagmatismo orogênico brasiliano e suas relações com o complexo Nova Venécia no extremo leste do Orógeno Araçuaí, Brasilinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesisreponame:Repositório Institucional da UFMGinstname:Universidade Federal de Minas Gerais (UFMG)instacron:UFMGORIGINALOrogenic magmatic events and their relations with the Nova Venécia complex in the southeastern sector of the Araçuaí orogen, Brazil.pdfOrogenic magmatic events and their relations with the Nova Venécia complex in the southeastern sector of the Araçuaí orogen, Brazil.pdfTese de doutoradoapplication/pdf247451006https://repositorio.ufmg.br/bitstream/1843/60874/1/Orogenic%20magmatic%20events%20and%20their%20relations%20with%20the%20Nova%20Ven%c3%a9cia%20complex%20in%20the%20southeastern%20sector%20of%20the%20Ara%c3%a7ua%c3%ad%20orogen%2c%20Brazil.pdfadfa82f95aa40bedcb100d32740f25e9MD51CC-LICENSElicense_rdflicense_rdfapplication/rdf+xml; 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dc.title.pt_BR.fl_str_mv |
Orogenic magmatic events and their relations with the Nova Venécia complex in the southeastern sector of the Araçuaí orogen, Brazil |
dc.title.alternative.pt_BR.fl_str_mv |
Magmatismo orogênico brasiliano e suas relações com o complexo Nova Venécia no extremo leste do Orógeno Araçuaí, Brasil |
title |
Orogenic magmatic events and their relations with the Nova Venécia complex in the southeastern sector of the Araçuaí orogen, Brazil |
spellingShingle |
Orogenic magmatic events and their relations with the Nova Venécia complex in the southeastern sector of the Araçuaí orogen, Brazil Cristina Santos Araujo U-Pb geochronology Hf-Nd isotopes Slab retreat Active margin Brasiliano orogeny Orogenic magmatism Araçuaí orogen Tempo geológico Isótopos Magmatismo – Brasil |
title_short |
Orogenic magmatic events and their relations with the Nova Venécia complex in the southeastern sector of the Araçuaí orogen, Brazil |
title_full |
Orogenic magmatic events and their relations with the Nova Venécia complex in the southeastern sector of the Araçuaí orogen, Brazil |
title_fullStr |
Orogenic magmatic events and their relations with the Nova Venécia complex in the southeastern sector of the Araçuaí orogen, Brazil |
title_full_unstemmed |
Orogenic magmatic events and their relations with the Nova Venécia complex in the southeastern sector of the Araçuaí orogen, Brazil |
title_sort |
Orogenic magmatic events and their relations with the Nova Venécia complex in the southeastern sector of the Araçuaí orogen, Brazil |
author |
Cristina Santos Araujo |
author_facet |
Cristina Santos Araujo |
author_role |
author |
dc.contributor.advisor1.fl_str_mv |
Antônio Carlos Pedrosa Soares |
dc.contributor.advisor1Lattes.fl_str_mv |
http://lattes.cnpq.br/0388600397612432 |
dc.contributor.advisor-co1.fl_str_mv |
Mahyra Ferreira Tedeschi |
dc.contributor.referee1.fl_str_mv |
Antônio Carlos Pedrosa Soares |
dc.contributor.referee2.fl_str_mv |
Tiago Amâncio Novo |
dc.contributor.referee3.fl_str_mv |
Valderez Pinto Ferreira |
dc.contributor.referee4.fl_str_mv |
Moacir José Buenano Macambira |
dc.contributor.referee5.fl_str_mv |
Caroline Cibele Vieira Soares |
dc.contributor.authorLattes.fl_str_mv |
http://lattes.cnpq.br/5662871155839581 |
dc.contributor.author.fl_str_mv |
Cristina Santos Araujo |
contributor_str_mv |
Antônio Carlos Pedrosa Soares Mahyra Ferreira Tedeschi Antônio Carlos Pedrosa Soares Tiago Amâncio Novo Valderez Pinto Ferreira Moacir José Buenano Macambira Caroline Cibele Vieira Soares |
dc.subject.por.fl_str_mv |
U-Pb geochronology Hf-Nd isotopes Slab retreat Active margin Brasiliano orogeny Orogenic magmatism Araçuaí orogen |
topic |
U-Pb geochronology Hf-Nd isotopes Slab retreat Active margin Brasiliano orogeny Orogenic magmatism Araçuaí orogen Tempo geológico Isótopos Magmatismo – Brasil |
dc.subject.other.pt_BR.fl_str_mv |
Tempo geológico Isótopos Magmatismo – Brasil |
description |
The Araçuaí – West Congo Orogenic System constitutes a confined orogen to a large sheath of the São Francisco – Congo Craton, amalgamated into the Gondwana Paleocontinent at the end of the Neoproterozoic. A long-lasting succession of granite production events (ca. 630 – 480 Ma) associated to the orogenic stages is a remarkable feature of the Araçuaí orogen. Located in the easternmost sector, the study area includes rocks of pre-, sin-, and post-collisional orogenic stage intruded in the Nova Venécia migmatitic paragneisses, interpreted as an arc-related basin. The new petrological investigation, bulk-rock chemistry, and isotopic analyses (zircon U-Th-Pb and Lu-Hf by LA-ICPMS, and whole-rock Sm-Nd) were carried out in representative rocks from the orogenic magmatism and the Nova Venécia complex. In this context, Santa Tereza and Jequitibá suites represent the more eastern expression of pre-collisional magmatism associated with the Rio Doce magmatic arc, while Ataléia suite represent the syn-collisional rocks, and the Aracê – Pedra Azul, Vitória, and Mestre Álvaro plutons record the post-collisional event. The Santa Tereza and Jequitibá suites yield a concordant age of 612 ± 3 Ma and 594 ± 3 Ma, respectively. Their isotopic data represent the least evolved magmatism record in this orogen (Santa Tereza suite: εHf(612) of +2.3 to -4.8 with TDM of 1.33 to 1.65 Ga and εNd(612Ma) of -0.06 to -7.05 with TDM of 1.4 a 2.04; Jequitibá suite: εHf(594) of -1.7 to -36.4 with TDM of 1.33 to 3.21 Ga and εNd(594) of -6.67 to -8.8 with TDM of 1.64 to 1.87). These suites consist of I-type intermediate to acid intrusions, metaluminous to slightly peraluminous, mainly magnesian and calcic to alkali-calcic compositions, with portions of Opx-bearing and subordinate gabbroic rocks. Data from the S-type Ataléia granite (583 ± 3 Ma; εHf(t) -3.2 to -8.1, TDM ages from 1.42 to 1.64 Ga) and Nova Venécia migmatitic paragneisses (582 ± 7 to 2363 ± 26 Ma - with age peaks at 617 ± 4 Ma (68%), 719 ± 22 Ma (14%), 839 ± 46 Ma (8%), and 922 ± 31 Ma (10%); εHf(t) +4.1 to -39.2, TDM ages from 1.20 to 3.47 Ga) suggest the proximity of the Nova Venécia basin to the continental margin and that this basin received significant sediment from the Rio Doce magmatic arc. Furthermore, the dataset for the post-collisional intrusions (Aracê – Pedra Azul pluton: 523 ± 2 Ma, εHf(t) -18.6 to -23.8, TDM ages from 2.25 to 2.47 Ga; Vitória pluton: 505 ± 1 Ma, εHf(t) -7.4 to -10.3, TDM ages from 1.58 to 1.71 Ga; Mestre Álvaro pluton: 527 ± 2 Ma, εHf(t) -0.7 to -8.8, TDM ages from 1.27 to 1.66 Ga) indicates magma hybridization at high temperature, involving country rocks in the petrogenesis of post-collisional intrusions. The rocks studied reflect a crustal section composed of I-type intermediate to acid intrusions, S-type metagranites, and paragneiss framework rocks metamorphosed under amphibolite to granulite facies, commonly migmatized. Compared to a wide compiled dataset, our data suggest that a magmatic arc is likely to have developed in the region with an initial extensional phase followed by a compressional phase and an arc migration westward. |
publishDate |
2023 |
dc.date.accessioned.fl_str_mv |
2023-11-13T17:14:48Z |
dc.date.available.fl_str_mv |
2023-11-13T17:14:48Z |
dc.date.issued.fl_str_mv |
2023-05-11 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/doctoralThesis |
format |
doctoralThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/1843/60874 |
url |
http://hdl.handle.net/1843/60874 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.rights.driver.fl_str_mv |
http://creativecommons.org/licenses/by-nc-nd/3.0/pt/ info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
http://creativecommons.org/licenses/by-nc-nd/3.0/pt/ |
eu_rights_str_mv |
openAccess |
dc.publisher.none.fl_str_mv |
Universidade Federal de Minas Gerais |
dc.publisher.program.fl_str_mv |
Programa de Pós-Graduação em Geologia |
dc.publisher.initials.fl_str_mv |
UFMG |
dc.publisher.country.fl_str_mv |
Brasil |
dc.publisher.department.fl_str_mv |
IGC - INSTITUTO DE GEOCIENCIAS |
publisher.none.fl_str_mv |
Universidade Federal de Minas Gerais |
dc.source.none.fl_str_mv |
reponame:Repositório Institucional da UFMG instname:Universidade Federal de Minas Gerais (UFMG) instacron:UFMG |
instname_str |
Universidade Federal de Minas Gerais (UFMG) |
instacron_str |
UFMG |
institution |
UFMG |
reponame_str |
Repositório Institucional da UFMG |
collection |
Repositório Institucional da UFMG |
bitstream.url.fl_str_mv |
https://repositorio.ufmg.br/bitstream/1843/60874/1/Orogenic%20magmatic%20events%20and%20their%20relations%20with%20the%20Nova%20Ven%c3%a9cia%20complex%20in%20the%20southeastern%20sector%20of%20the%20Ara%c3%a7ua%c3%ad%20orogen%2c%20Brazil.pdf https://repositorio.ufmg.br/bitstream/1843/60874/2/license_rdf https://repositorio.ufmg.br/bitstream/1843/60874/3/license.txt |
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MD5 MD5 MD5 |
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Repositório Institucional da UFMG - Universidade Federal de Minas Gerais (UFMG) |
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|
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1803589252094623744 |