Reassessing the spatial and temporal evolution of the Southeast Asian Tin Belt: Insights into recurrent tin mineralization

Abstract

The Southeast Asian Tin Belt is one of the world's most prolific tin-producing regions, comprising over 100 Sn deposits distributed across three granite provinces: the Eastern, Main Range, and Western Provinces. Despite its metallogenic significance, the spatiotemporal evolution of tin-associated granites and the mechanisms underlying recurrent tin mineralization across the entire belt remain unresolved. In this review, we integrate new and previously published UPb ages of cassiterite and zircon, trace element and Hf isotopic compositions of zircons, and bulk-rock geochemical data from key deposits and granites in southwestern China and Southeast Asia. Our results reveal six discrete episodes of tin mineralization from the Permian to Miocene. Permian (∼290–260 Ma) deposits in eastern Malaysia are associated with granites east of the Paleo-Tethys suture zone, whereas Triassic (∼240–200 Ma) deposits occur within the Main Range Province on both sides of the suture, extending from Indonesia through Malaysia and Thailand, to southwestern China. Cretaceous to Cenozoic (∼130–15 Ma) deposits in the Western Province are hosted by granites within the Sibumasu–Baoshan–Tengchong Block. Tin mineralization across the Southeast Asian Tin Belt reflects episodic remelting of a long-lived crustal inheritance comprising Proterozoic to Early Paleozoic metasedimentary rocks that were intensely weathered but not significantly Sn-enriched. These melting events were episodically triggered by asthenospheric upwelling and slab dynamics during successive subduction–collision cycles involving the Paleo-, Meso-, and Neo-Tethys oceans and the India–Asia collision. Tin enrichment is closely associated with high degrees of magma fractionation and a redox evolution toward reducing conditions. The temporal synchronization of tin-forming events across provinces highlights substantial, underexplored metallogenic potential, particularly along intracontinental shear zones and in regions lacking documentation of Early Cretaceous tin systems. Our findings provide a geodynamic and geochemical framework for understanding recurrent tin mineralization in the Southeast Asian Tin Belt and analogous collisional orogens worldwide.