Re-Os Isotopic Dating of Molybdenite from the Daheishan Molybdenum Deposit of Jilin Province and Its Geological Significance

The Daheishan molybdenum deposit is a large-scale porphyry molybdenum deposit discovered in 1950s in Jilin Province. This study provides a high-precision Re-Os isotopic dating for ten molybdenite separated from the different ore types with an isochron age of (168.2±3.2) Ma (MSWD=0.56). The results indicate that the deposit was formed in the early of Yanshanian period. The content of element Re from the molybdenite and S isotope composition from the pyrites show that the oreforming materials may come from mixed crustal and mantle sources.