Re-Os isotopic dating of molybdenites from the Yuangezhuang pluton in Jiaodong and its geological significance

The Yuangezhuang pluton lies in Muping block, Yantai, Shandong Province. It is a typical granitic complex of Weideshan Late Yanshanian super-unit in Jiaodong. In this study, direct Re-Os dating of molybdenites collected from the granitoids was carried out, and the major elements and trace elements in whole rock samples were also analyzed. The results show that the pluton probably belongs to a kind of granite derived from mantle-crust and is characterized by high potassium and alkali as well as metaluminous to peraluminous nature. Besides, the isochron age is 117.8±5.7 Ma, with a weighted average of 118.27±0.70 Ma, similar to data of the metallogenetic epoch and characteristics of the host rock from many known Cu-Mo deposits in Late Yanshanian period. This suggests that it probably has a good prospect for molybdenum polymetallic mineralization.