SHRIMP zircon U-Pb dating of the Huangfengzhai pluton in eastern Nanling and its geological implications

The Huangfengzhai pluton is located in the eastern sectionof tungsten-tin polymetallic metallogenic belt in the Nanling region. Thisstudy carried out SHRIMP zircon U-Pb dating and lithological and geochemical anlyzses for quartz monazites from the Huangfengzhai pluton. The results show thata zircon U-Pb age of quartz monzonite from the Huangfengzhai pluton is 231±3 Ma, belonging to late Middle Triassic. Lithological, mineralogical and geochemicalanalyses suggest that the pluton is rich in Si, Al and Ca, with medium alkali,indicating that the pluton belongs to high-K, calc-alkaline series, weakly-perluminous S-type granitoids. The pluton is also depleted in Sr, Ba, Nb, P and Ti, but relatively enriched in Rb, Th, Ce, Zr and Sm, with high ΣREE content, distinct LREE and HREE differentiation, and weak negative Eu anomalies. Zircon εHf(t)values range from -15.25 to -2.88 and Hf two-stage model age values are 1.87～2.22 Ga, indicating that the Huangfengzhai pluton was derived from partial melting of mafic rocks at the bottom of upper crust. It can be inferred that the Huangfengzhai pluton might form at a syncollosion tectonic setting.