• 责任者：Tang Yongyong (State Key Laboratory of Ore Deposit Geochemistry ; Institute of Geochemistry ; Chinese Academy of Sciences ; Guiyang 550002 ; China) ; Bi Xianwu
• 刊名：Geochimica
• 出版年：2013
• 卷期：42(5)
• 关键词：铅锌矿床 ; lead-zinc deposit ; 同位素地球化学 ; isotope geochemistry ; 兰坪盆地 ; Lanping Basin
• 页码：p.467-480
• 图表：5 illus., 2 tables, 69 refs.
• 分类号：1001
• issnNo：ISSN0379-1726
• isbnNo：CN44-1398/P

     The Jinding Zn-Pb deposit in Yunnan Province, is the largest Zn-Pb deposit in China, and one of the world-class super-large deposits with Zn＋Pb reserves more than 10 Mt. A systematic study of carbon, oxygen and strontium isotopes has been carried out on main mineralization vein calcites and post-mineralization nodule calcites. The main mineralization vein calcites show a large variation of δ^l3C （-23.0‰--2.6‰）, indicating mixed carbon source of sedimentary organics and marine carbonates, with high δ^l8O （22.1‰ - 23.5‰） similar to the sediments, and high Sr contents （163 - 1920 μg/g）, as well as ^87Sr/^86Sr （0.709860 - 0.710362）. The post-mineralization nodule calcites have homogeneous δ^l3C （-7.0‰ - -6.2‰） and  δ^l8O （20.2‰ - 22.4‰）, high contents of Sr （240 - 817 μg/g） and ^87Sr/^86Sr （0.710235 - 0.710347）. Besides, the calculated δ^l8O of the ore-forming fluid equilibrated with the post-mineralization nodule calcites, range from 7.1‰ to 12.7‰ at 150 -200℃ by the equation 1000 In acalcit ter = 4.01×106/T^2 - 4.66×10^3/T＋1.71 （Zheng, 1991）. Pb isotopes in sulfides （^206pb/^204pb 18.373 - 18.452, ^207pb/^204pb 15.605 - 15.668, ^208pb/^204pb 38.524 - 38.726） plot between the line of orogenic Pb and the line of upper crustal Pb in Pb evolution diagram （Zartman and Doe, 1981）, consistent with the Himalayan magmatisms and partially overlapping with the upper crustal sedimentary rocks in the Lanping basin. These indicate that there were at least two episodes of hydrothermal mineralization in Jinding. The ore-forming fluid at the main mineralization stage might be the formation water originating from organic-rich limestones of the Upper Triassic Sanhedong Formation, apart from some involvement of deep-sourced components, whereas the ore-forming fluid at the post-mineralization stage is dominated by meteoric water. During migrating in the basin, the ore-forming fluids reacted with wall rocks and acquired high contents of radiogenic S7Sr. Metals were likely provided by the Upper Triassic Sanhedong Formation limestones and Himalayan igneous rocks.