Evidence of Siderian juvenile-like contribution to the continental arc magmatism in the Western Guanambi-Correntina block, São Francisco Craton (Brazil)

The Guanambi-Correntina Block, a basement relic within the São Francisco Craton, played a determining role in the stabilization of the South American plate during the Paleoproterozoic, preceding the formation of the Nuna-Columbia supercontinent. Despite its magnitude, the western part of the block is mainly hidden by Neoproterozoic to Phanerozoic sedimentary covers, limiting the exposition of a significant section of the craton. In the study area, the Correntina Complex and the Rio Corrente Suite crop out within the Paleoproterozoic basement in an erosional window showing a diverse assemblage of plutonic, volcanic, and metasedimentary lithologies interpreted as part of a continental arc setting. This study employs a comprehensive approach encompassing geological mapping, lithogeochemistry, whole rock Sm–Nd and Rb–Sr isotopic analyses, and zircon U–Pb-Hf data from metaplutonic and metavolcanic rocks aiming the investigation of the pre-stabilization tectonic stages of the São Francisco lithosphere. The U–Pb-Hf zircon data reveal a crystallization age of 2183 ± 9 Ma for the acid volcanism, characterized by a juvenile isotopic signature (εHf = +5.7 to +9.4) and TDMHf between 2.2 and 2.4 Ga. Nd–Sr whole rock geochemistry of a sanukitoid rock from the metaplutonic unit indicates εNd(t) of +3.05, TDMNd of 2.31 Ga, and 86Sr/87Sr(i) of 0.70173, for which a zircon U–Pb crystallization age of 2324 ± 9 Ma has been obtained, establishing it as the oldest known Paleoproterozoic occurrence in the São Francisco Craton basement. The results unveil the Correntina Complex as one of the oldest paleoproterozoic records of continental magmatic arc relics within the São Francisco Craton, recording one of the earliest Paleoproterozoic events in the eastern South American plate. A geological evolution model envisages juvenile crustal production during the Siderian to Rhyacian periods in the western Guanambi-Correntina Block, corroborating similar episodes documented for other regions of the craton. This study contributes to our understanding of the early tectonic processes and improves the knowledge of the paleoproterozoic terranes that shaped the São Francisco Craton.