ZHANG Yun-xin1, WU Yue2, TIAN Guang3, SHEN Liang4, ZHOU Yun-man1, DONG Wen-wei1, ZENG Rong4, YANG Xing-chao4, ZHANG Chang-qing5
(1. Yunnan Gold Mining Industry Group, Kunming 650000, China;
2. School of Earth Environment and Water Resource, Yangtze University, Wuhan 430100, China;
3. Faculty of Geoscience and Mineral Resources, China University of Geosciences, Beijing 100083, China;
4. Lehong Lead-zinc Mining Ltd. of Yunnan Haolong Group, Ludian 657107, China;
5. Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 100037, China)
Abstract: The Lehong Zn-Pb deposit is a large newly discovered MVT-type deposit in the border area of the Provinces of Sichuan, Yunnan and Guizhou, China. Rb-Sr data for sphalerite from the Lehong deposit define an isochron age of 200.9±8.3 Ma, corresponding with the late Indosinian orogeny. The 87Sr/86Sr ratios of sphalerite indicate that the basement rocks and the covering sedimentary strata are the main source of the metal for the sphalerite mineralization. The high δ34S values of most metallic sulfides from the different ore stages suggest that sulfur reduced by thermochemical sulfate reduction (TSR) is the source of sulfur involved in ore formation and that seawater sulfate might be the ultimate source of the sulfur. We believe, based on the regional tectonic evolution and ore geology of the deposit, that the Lehong MVT-type deposit could have been formed during the later stage of the Indosinian orogeny, which may be the driving force of the large-scale migration of ore-forming fluids.
Key words: sulfur isotope; Rb-Sr dating of sphalerite; MVT deposit; Lehong Pb-Zn deposit
ACTA MINERALOGICA SINICA Vol. 34, No. 3, 2014, Page 305-311
