Relationship Between Magmatic Evolution and Mineralization in the Tengchong–Lianghe Tin Metallogenic Belt

This chapter systematically investigates the Mesozoic–Cenozoic evolution of granitic rocks in the Tengchong–Lianghe tin belt and their relationship with tin mineralization. Zircon U–Pb geochronology, geochemistry, and Hf isotope analyses of ten representative intrusions from the Jurassic, Early Cretaceous, Late Cretaceous, and Paleogene periods revealed that the granitic rocks in the study area are predominantly S-type rocks derived from crustal anatexis. They are characterized by high differentiation (DI > 90), enrichment in silicon and alkalis, strong peraluminosity, and pronounced negative Eu anomalies. The tin-bearing granites formed in a tectonic setting of continental‒continental collision and transitioned to postcollision, marked by high Rb levels, low Sr levels, highly fractionated REE patterns, and negative εHf(t) values (− 7.5 to − 11.7). Based on 166 granite intrusion datasets, a discrimination model for tin-bearing granites was established using SiO2, Al2O3/TiO2, δEu, Zr, LREE, HREE, Rb, and Sr, providing effective indicators for regionally targeted tin exploration.