Abstract:
Pangushan granite is genetically related to the well-known Pangushan large-sized tungsten deposit. However, due to great depth, its petrologic and geochemical data had been lacking until it was discovered by the Nanling Scientific Drilling Project (SP-NLSD-2) recently. In this paper, the petrologic and geochemical study conducted by the authors is reported. The granite is found to be ultra-acidic, alkali-rich, Na-poor, K-rich, meta-to weak-peraluminous and K-high calc-alkaline. Its corresponding granitic magma is highly evolved and W and Bi values are significantly higher than their average values in Yanshanian granite in Nanling region, indicating that they were the major ore-forming material source. When the granitic magma was evolved to the greisenization stage, Mo, Bi, Cu, Pb and REE were enriched, while W and Sn were depleted because of their migration into the hydrothermal solution. The intrusion of the Pangushan granite happened during intraplate extension.