Paleoproterozoic orogenic gold system in the Contendas-Mirante belt, São Francisco Craton, Brazil: Insights from lithogeochemistry, U–Pb detrital zircon geochronology, and geodynamic analysis

Orogenic gold systems are important sources of Paleoproterozoic gold mineralization in cratonic settings worldwide and are commonly associated with convergent-margin tectonics and crustal-scale fluid flow. In the northern São Francisco Craton, eastern Brazil, several Rhyacian-Orosirian gold occurrences are known; however, the geodynamic context and structural framework controlling mineralization in the Contendas-Mirante volcanosedimentary belt remain poorly constrained. This study integrates geological and structural mapping, core sample analysis, whole-rock geochemistry, U–Pb detrital zircon geochronology, and aerogeophysical data to constrain the tectonic setting and mineralization processes of the Contendas-Mirante belt. Metabasalts of the Neoarchean lower unit display light rare earth element-enriched patterns, elevated Th and U contents, and pronounced negative Nb–Ta–Ti anomalies, consistent with a continental geochemical signature. Elevated Th/Yb, La/Yb, and Th/Nb ratios may have been partly modified by secondary processes and are therefore considered supportive, but not restricted to an arc-like continental geochemical signature, as they may also reflect crustal contamination during the evolution of basaltic magma. U–Pb detrital zircon ages from associated phyllites yield a maximum depositional age of 2626 ± 31 Ma, indicating provenance from proximal Neoarchean volcanic sources along a continental margin. Structural analyses reveal a dominant north–south-trending crustal-scale lineament formed during the Rhyacian-Orosirian tectonothermal event, itself associated with the accretion of oceanic and continental arcs and older continental blocks in the northern São Francisco Craton. Subordinate northwest-southeast and northeast-southwest structures controlled the distribution of lithologies and fluid migration. Gold mineralization in the Contendas-Mirante belt is hosted by brecciated ferruginous metacherts of the lower unit and is spatially associated with quartz-sericite schists, reflecting fluid focusing within brittle-ductile deformation zones where iron-rich sedimentary rocks acted as effective chemical and rheological traps. The results support a tectonic evolution involving Neoarchean continental-margin volcanism, followed by the Rhyacian-Orosirian tectonothermal event and orogenic gold mineralization, most likely within a continental arc system. The Contendas-Mirante belt mineralization exhibits key temporal, structural, and geodynamic characteristics of Paleoproterozoic orogenic gold systems in the Congo, Amazonian, and West African cratons, contributing to broader reconstructions of crustal growth, metallogenesis, and gold exploration models in the São Francisco Craton and analogous cratonic provinces worldwide.