文摘
The ages for porphyry Mo deposits in south segment of Da Hinggan Mountains, Northeast China, are not well known. Five molybdenite samples from the Aolunhua ( porphyry Mo deposit, five molybdenite samples from the Yangchang () porphyry-quartz vein Mo deposit and two molybdenite samples from the Banlashan ( porphyry Mo deposit were selected for Re-Os dating. Three deposits are spatial-temporally associated with the granite porphyry stock. Re-Os isochron age of 131.2±1.9 Ma was obtained for the Aolunhua porphyry Mo deposit. The Yangchang Mo deposit provides isochron age of 138.5±4.5 Ma for two groups of molybdenite (within porphyry ore and within quartz vein). The Banlashan porphyry Mo deposit provides model ages of 140.5±2.4 and 143±2.2 Ma. All of these Re-Os ages are consistent presumed Yanshanian ages for granite intrusions, formed in crust thinning setting in Cretaceous in North China.