Contrasting P-T-t paths of basement and cover within the Búzios Orogen, SE Brazil – Tracking Ediacaran-Cambrian subduction zones

Registro completo de metadados
MetadadosDescriçãoIdioma
Autor(es): dc.contributorUniversidade Federal do Rio de Janeiro (UFRJ)-
Autor(es): dc.contributorUniversidade de São Paulo (USP)-
Autor(es): dc.contributorUniversidade Estadual Paulista (UNESP)-
Autor(es): dc.creatorVieira, Thayla Almeida Teixeira-
Autor(es): dc.creatorSchmitt, Renata da Silva-
Autor(es): dc.creatorMendes, Julio Cezar-
Autor(es): dc.creatorMoraes, Renato-
Autor(es): dc.creatorLuvizotto, George Luiz-
Autor(es): dc.creatorde Andrade Silva, Raphaela Lopes-
Autor(es): dc.creatorVinagre, Rodrigo-
Autor(es): dc.creatorMedeiros, Silvia Regina de-
Data de aceite: dc.date.accessioned2025-08-21T21:23:28Z-
Data de disponibilização: dc.date.available2025-08-21T21:23:28Z-
Data de envio: dc.date.issued2022-04-28-
Data de envio: dc.date.issued2022-04-28-
Data de envio: dc.date.issued2021-12-31-
Fonte completa do material: dc.identifierhttp://dx.doi.org/10.1016/j.precamres.2021.106479-
Fonte completa do material: dc.identifierhttp://hdl.handle.net/11449/222994-
Fonte: dc.identifier.urihttp://educapes.capes.gov.br/handle/11449/222994-
Descrição: dc.descriptionDeeply eroded collisional orogens show complex structural and inverted stratigraphic relations with juxtaposition of rock stacks from distinct crustal levels, origins and ages, hence with contrasting P-T-t paths during convergent tectonics. This paper presents petrochronological data on Paleoproterozoic (basement) and Ediacaran (cover) gneisses tectonically interleaved during the Ediacaran-Cambrian Búzios Orogeny, in southeastern Brazil. U-Pb in zircon and EPMA U-Th-Pb in monazite data, coupled with geothermobarometric data, plus Zr-in-rutile, reveal that at a first orogenic stage (ca. 530–520 Ma), these units were at distinct crustal levels. Samples within the Paleoproterozoic basement show metamorphic near-peak conditions of ∼800 °C and 10 kbar, at a depth of c.37 km. Contrastingly, Ediacaran kyanite-orthoclase-garnet-biotite granulite with retrometamorphic sillimanite (cover) reached near-peak conditions of 15 kbar and 818 °C–785 °C at depths of c. 55 km, in high-pressure granulite facies. This deep burial of Ediacaran sediments in less than 20 m.y. would be compatible with a low angle subduction zone active from ca. 550 to 530 Ma. Intrusion of ca. 550 Ma tholeiitic dykes in the Paleoproterozoic gneiss indicates a high geothermal gradient for this subduction setting, which is consistent with a low subduction rate. In a second orogenic stage (ca. 520–500 Ma), these distinct stratigraphic units were placed tectonically side by side during a fast exhumation, preserving an inverted metamorphic stack. The cover underwent retrometamorphic conditions of 800 °C and 10 kbar on a clockwise return path due to decompression. It is proposed here that the contact between reworked units within a Paleoproterozoic continental crust and Ediacaran magmatic and sedimentary units represent the suture of an Ediacaran NW-subduction of the Angola continental paleomargin below the Oriental Terrane of the Ribeira belt. This paper reports the highest pressure recorded in Ediacaran-Cambrian metamorphic rocks from the Brasiliano belts along the actual South Atlantic continental margins. The suture we propose here is aligned along strike, with a medium to high-pressure Ediacaran metamorphic occurrence 700 km to the SW, in the Curitiba Terrane.-
Descrição: dc.descriptionPrograma de Pós-Graduação em Geologia – PPGL – IGEO Universidade Federal do Rio de Janeiro UFRJ, Athos da Silveira Ramos Avenue, 274, block G – Cidade Universitária, Ilha do Fundão-
Descrição: dc.descriptionDepartamento de Geologia – IGEO Universidade Federal do Rio de Janeiro-
Descrição: dc.descriptionDepartamento de Mineralogia e Geotectônica Instituto de Geociências Universidade de São Paulo-
Descrição: dc.descriptionDepartamento de Geologia Universidade Estadual Paulista-
Descrição: dc.descriptionDepartamento de Geologia Universidade Estadual Paulista-
Idioma: dc.languageen-
Relação: dc.relationPrecambrian Research-
???dc.source???: dc.sourceScopus-
Palavras-chave: dc.subjectCabo Frio Tectonic Domain-
Palavras-chave: dc.subjectGeothermobarometry-
Palavras-chave: dc.subjectPetrochronology-
Palavras-chave: dc.subjectU-Pb zircon-
Palavras-chave: dc.subjectU-Pb-Th monazite-
Palavras-chave: dc.subjectZr-in-rutile-
Título: dc.titleContrasting P-T-t paths of basement and cover within the Búzios Orogen, SE Brazil – Tracking Ediacaran-Cambrian subduction zones-
Tipo de arquivo: dc.typelivro digital-
Aparece nas coleções:Repositório Institucional - Unesp

Não existem arquivos associados a este item.