The Dongyuan W-Mo deposit, located in Qimen County in southern Anhui Province, is the largest W-Mo deposit in this region thus far reported. The deposit consists of Dongyuan, Xiyuan, and Jiangjia ore blocks. The W-Mo orebodies in Jiangjia and Xiyuan ore blocks are mainly occurred in granodiorite porphyry and the nearby contact zone, with the major type of veinlet-disseminated and disseminated mineralization. The measured δ34SV-CDT values of Jiangjia (2. 6%o to 4. 9%c) and Xiyuan (4. 0%e to 4. 7%e) ore blocks vary in a very limited range and suggest that the formation of W-Mo ore-body is closely related to magmatism, which involve the sulfur may be leached from the granodiorite intrusion. Based on tectonic patterns of lead isotope and related paramerters, the lead isotopic compositions of Jiangjia (206Pb/204Pb = 18.222 to 18.369, 207Pb/204 Pb = 15.579 to 15. 618, 208Pb/204Pb =38. 264 to 38.400) and Xiyuan (206Pb/204Pb = 18. 240 to 18.251,207Pb/204Pb = 15.604 to 15. 618, 208Pb/204Pb =38. 360 to 38.442) indicate that the metallogenic material is closely related to magmatism, and their leads are characterized by the source of lower crust and show crust-mantle mixing.%皖南东源钨钼矿位于安徽省祁门东源境内,是该地区目前已知规模最大的钨钼矿床.它由东源、江家和西源3个矿段组成.江家和西源矿段的钨铜矿体主要产于花岗闪长斑岩体内及其接触带附近,以细脉浸染状和浸染状矿化类型为主.测试结果表明:江家矿床δ34SV-CDT值介于2.6‰ ～4.9‰之间,西源矿床δ34SV-CDT值介于4.0‰～4.7‰之间,组成稳定;钨钼矿体的形成与岩浆作用相关,硫可能是从花岗闪长岩体中淋滤而来.江家矿床矿石样品208Pb/204Pb值介于38.264～38.400之间,207Pb/204Pb值介于15.579～15.618之间,206Pb/204Pb值介于18.222～ 18.369之间;西源矿床矿石样品208Pb/204Pb值介于38.360～38.442之间,207pb/204Pb值介于15.604～15.618之间,206Pb/204Pb值介于18.240～18.251之间;根据铅构造模式图解和其参数综合分析,表明成矿物质与岩浆作用密切相关,整体上显示下地壳来源特征,具有壳幔混合特点.
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