Provenance study of the Lubok Antu Mélange from the Lupar valley, West Sarawak, Borneo: Implications for the closure of eastern Meso-Tethys?

The Lubok Antu Mélange is exposed along one of the most important tectonic lineaments, Lupar Line in Sarawak, Borneo. However, depositional age poorly known, and no provenance studies have been conducted so far. Here, we use geochemical, Nd isotopic detrital zircon UPb analyses samples from to constrain routing order better understand Borneo's evolution history. Bulk rock geochemistry reveals that was deposited a continental arc setting related Paleo-Pacific subduction margin. New data suggest maximum for ca. 115 105 Ma. with strongest Jurassic peak interpreted be sourced Mesozoic subduction, contributions West Borneo, Malay Peninsula possibly Sumatra. Compared uppermost Cretaceous sedimentary rocks our study records change source latest erosion basement magmatic subduction-related probably located offshore what now South Vietnam Schwaner Mountains SW This indicates rapid uplift exhumation could initiated Cretaceous, which may imply arrival Borneo closure eastern Meso-Tethys at time.