Molybdenite Re–Os and muscovite 40Ar/39Ar dating of quartz vein-type W–Sn polymetallic deposits in Northern Guangdong, South China

Northern Guangdong is an important part of Nanling tungsten–tin metallogenic belt, South China. The tungsten mineralization in this area consists of mainly quartz–wolframite vein-type mineralization, with W–Sn polymetallic deposits mostly distributed at the outer contact zone between concealed Late Jurassic granitic stocks and Cambrian–Ordovician low-metamorphosed sandstones and shales. Molybdenite Re–Os and muscovite ⁴⁰Ar/³⁹Ar isotopic dating of three typical tungsten vein-type deposits (Yaoling, Meiziwo, and Jubankeng) in northern Guangdong, show that two episodes of Late Jurassic W–Sn polymetallic mineralization occurred in this area: an early episode during the Late Jurassic (158–159?Ma) represented by the Yaoling, Hongling, and Meiziwo tungsten deposits, and a younger event during the Early Cretaceous (138?Ma) represented by the Jubankeng deposit. Analysis of available radiometric ages of several W–Sn deposits in the Nanling region indicate that these deposits formed at several intervals during the Mesozoic at 90–100, 134–140, 144–162, and 210–235?Ma, and that large-scale W–Sn mineralization in this region occurred mainly between 150 and 160?Ma.