Geochemistry and detrital Zircon U–Pb geochronology of beach sediments from the southern Red Sea, Sudan: Implications for paleoweathering and provenance

Active rift basins, such as the Red Sea, provide natural laboratories for studying sediment dynamics, with implications for global provenance and resource exploration. This study integrates geochemistry and detrital zircon U–Pb geochronology to investigate beach sediments along Sudan's Red Sea coast, a rift margin within the Neoproterozoic Arabian–Nubian Shield (ANS). Three kinds of sand deposits have been observed: white, black, and island sands. The Al₂O₃/TiO₂ ratio is sensitive to the composition of the source rock, suggesting a predominantly intermediate source for the islands' sediments and a mafic source for Trinkitat beach, with low-to-moderate weathering (CIW' = 32–76.6), consistent with semiarid rift margins. Zircon ages reveal two populations from the ANS (595–945 Ma) and Cenozoic volcanic rocks (22–42 Ma). These ages are interpreted to originate primarily from the Pan-African orogeny and specific terranes within the ANS for the older population and from syn-rift volcanism in the Red Sea Hills Alkaline Province for the younger population. Coast sands are derived from the ANS, but the black sands are mixed with syn-rift volcanic input from the Red Sea Hills Alkaline Province. Heavy mineral enrichment (ilmenite, rutile, zircon) at Trinkitat, driven by longshore currents, suggests placer deposit potential, analogous to Australia's Murray Basin. These findings highlight tectonic controls on provenance, with aridity limiting chemical alteration, contributing to global debates on sediment dispersal in rift basins. By comparing Sudan's Red Sea coast to global rift systems, this study advances models of sediment transport and supports critical mineral exploration (e.g., Ti, Zr).