SHRIMP zircon U-Pb dating of andesite and its constraint on mineralization age in Xiabulang Cu-Pb-Zn deposit, Tongren County, Qinghai
Li Xiucai1, Niu Manlan1, Wu Qi1, Fu Changlei2, Guo Xianqing3, Xie Xing4
1. Department of Resources and Environment, Hefei University of Technology, Hefei 230009;
2. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037;
3. Institute of Mineral Resource, Chinese Academy of Geological Sciences, Beijing 100037;
4. School of Earth Science and Resources, Chang'an University, Xi'an 710054
The Xiabulang Pb-Zn deposit is one of the newly discovered VMS-type Cu-Pb-Zn small-scale polymetallic deposit in the juncture of Qinling, Qilian and Kunlun orogens. The ore body occurred as disseminated, net veined and stripped in andesite, and was coexistent with chalcopyrite, pyrite, stibnite, galenite and sphalerite. The ore-bearing rock had experienced strong alterations such as chloritization, carbonatization, silicification, and the major ore-related alteration is silicification. The width of alteration was varied as the thickness of the ore body changing. Based on field geological survey, the SHRIMP zircon U-Pb dating of ore-hosting andesite yielded age of 240.1±2.4 Ma(MSWD=0.31), indicated that rock-forming time might have been the product of Middle Triassic volcanic activities, also represent the forming age of the Xiabulang Cu-Pb-Zn deposit. The mineralization of the Xiabulang Cu-Pb-Zn deposit was closely related with the massive intermediate to acidic magmatism of Qinling-Qilian-Kunlun region in the Middle Triassic under continent margin arc environment resulted from the northward subduction of paleotethyan ocean.