Rhyacian-Orosirian isotopic records from the basement of the Araçuaí-Ribeira orogenic system (SE Brazil): Links in the Congo-São Francisco palaeocontinent

Lithogeochemical and Nd-Sr isotope data of the orthogranulites of the Juiz de Fora complex, SE-Brazil: insights from a hidden Rhyacian Orogen within the Ribeira belt

“…The Juiz de Fora and Mantiqueira basement complexes show deep reworking and crustal shortening during the Neoproterozoic Brasiliano orogeny, given by structural, metamorphic and geochronological evidence (Heilbron et al 2010, Degler et al 2018. In particular, the JFC and interlayered supracrustal rocks underwent granulite facies metamorphism, as indicated by mineral paragenesis with peak temperatures between 800 and 895ºC (Duarte et al 2000, Bento dos Santos et al 2011, Degler et al 2018. Additionally, the JFC rocks exhibit retrograde mineral paragenesis and a pervasive mylonitic foliation, acquired during the final stages of thrusting during the Brasiliano orogeny.…”

“…The available zircon U-Pb crystallization ages mainly span between 2.20 to 2.07 Ga (Machado et al 1996, Silva et al 2002, Noce et al 2007, André et al 2009, Heilbron et al 2010, Degler et al 2018, Kuribara et al 2019. In contrast, some mafic granulites with documented zircon U-Pb ages of ca.…”

“…The investigation of the basement inliers in the central segment of the Ribeira belt is one of the key points for understanding the nature of the Neoproterozoic orogen in SE-Brazil (Heilbron et al 1998, 2010, Noce et al 2007, Degler et al 2018. In a broader view, this system includes the Araçuaí orogen to the north (Pedrosa-Soares & Noce 1998, Pedrosa-Soares & Wiedmann-Leonardos 2000, Pedrosa-Soares et al 2001, and the Dom Feliciano belt to the south, as well as the West-Congo and Kaoko belts Lithogeochemical and Nd-Sr isotope data of the orthogranulites of the Juiz de Fora complex, SE-Brazil: insights from a hidden Rhyacian Orogen within the Ribeira belt in Africa (Miller 1983, Seth et al 1998, Goscombe & Gray 2007, Goscombe et al 2017.…”

“…In order to contribute to the understanding of the tectonic evolution of the JFC, this work brings new petrographic, geochemical and Nd-Sr isotope data, as well as systematic geologic mapping of the JFC orthogranulites in southern Rio de Janeiro. The new data is compared with previously published U-Pb geochronology and geochemistry works on the study area (Machado et al 1996, Heilbron et al 2010, as well as with regional data from the JFC (Silva et al 2002, Noce et al 2007, Degler et al 2018, Kuribara et al 2019.…”

The Vazante and Canastra groups revisited: Sm-Nd and Sr isotopes - evidence for contribution from Tonian intraplate magmatism during passive margin development along the SW São Francisco margin, Brazil

“…Since the end of the Rhyacian and Orosirian orogenic events that amalgamated the basement of the São Francisco-Congo Paleocontinent (Noce et al 2000, Barbosa & Sabaté 2004, Barbosa et al 2015, Caxito et al 2015, Degler et al 2018, this ancient paleo-continental block remained essentially stable from ~1.80 Ga until the onset of Neoproterozoic Brasiliano orogenic events (~0. 64 Ga).…”