Geochemical and mineralogical study of zircon, apatite, and wolframite in the Xiatongling W-Mo-Be deposit, South China: Implications for key factors to W-Mo-Be mineralization

The Xiatongling tungsten‑molybdenum‑bismuth (W-Mo-Be) deposit, located in the Nanling metallogenic belt, is a stockwork and quartz vein-type W-Mo-Be system developed within and along the contact zone of a medium- to fine-grained granite intrusion. Although previous studies have focused on the magmatic age and geochemical features of the intrusion, and indirectly constrained the mineralization age using molybdenite geochronology, the precise metallogenic chronology, sources of ore-forming materials, and key factors controlling W-Mo-Be mineralization remain poorly understood. This study presents an integrated geochemical and geochronological investigation of zircon, apatite, and wolframite from the deposit to constrain its petrogenesis and mineralization. The zircon U Pb age of the granite (ca. 154 Ma) corresponds to the wolframite U Pb age (ca. 154 Ma), establishing a genetic link between magmatism and tungsten mineralization. Geochemical data indicate that the granite is weakly peraluminous (A/CNK = 1.03 to 1.08), characterized by high SiO₂, U, and Ta, and low Ba, Sr, and Zr + Nb + Ce + Y, typical of highly fractionated S-type granites. Zircon ε Hf (t) values of −7.75 to −10.64 and apatite ε Nd (t) values of −15.56 to −8.97 indicate derivation from the Proterozoic metasedimentary basement of the Wugongshan area, which was characterized by pre-enrichment in W, Mo, and Be. Integrated whole-rock and wolframite geochemical data reveal consistent and pronounced negative Eu anomalies in both wolframite and the Xiatongling granite. Combined with robust geochronological constraints, these findings support the interpretation that the reduced ore-forming fluids were directly exsolved from the reduced, granitic magma. Based on the integrated evidence, we conclude that pre-enrichment of the source and extensive fractional crystallization were key factors for the formation of the Xiatongling W-Mo-Be deposit. • U–Pb ages show a link between Xiatongling mineralization and granitic magmatism. • Ore-forming fluids were directly inherited from the granitic magma. • The magma source originates from the Wugongshan metasedimentary basement. • Source pre-enrichment and fractional crystallization controlled W-Mo-Be deposit formation.