Re-Os Dating of Molybdenite from Stratiform Skarn Orebodies in the Datuanshan Copper Deposit, Tongling, Anhui Province, and Its Geological Significance
MEI Yanxiong~(1)) MAO Jingwen~(1,2)) LI Jinwen~(1)) DU Andao~(3))1) Institute of Mineral Resource, CAGS, Beijing, 100037; 2) China University of Geosciences, Beijing, 100083; 3) National Research Center of Geoanalysis,CAGS,Beijing,100037
The Datuanshan copper deposit in Tongling, Anhui Province, is located in the middle section of the Middle and Lower Yangtze Valley iron-copper metallogenic belt. The metallogenic epoch of the deposit was previously regarded as Yanshanian on the basis of the ages of intermediate-acid intrusive rocks related to the ore-forming process. The authors collected 6 molybdenite samples from stratiform skarn orebodies in the Datuanshan copper deposit for Re-Os precise dating. The isochron age is 139.1±2.7 Ma, and the Re-Os model ages vary from 138.0～140.8 Ma. These age data are concordant with ~(40)Ar/~(39)Ar ages, 135.8～139.8 Ma, of the ore-forming intermediate-acid intrusive rocks. The Datuanshan copper deposit and the copper-sulfur-gold deposits in Tongling area are products of Mesozoic large-scale metallogenic process in East China, coupling with the geodynamic event of the lithospheric tectonic regime transition.