Age and Genesis of the Laodaizhanggou Pb-Zn-Ag Deposit in the Fudian Ore Field,Southern North China Craton:Implications for Regional Mineral Prospecting  

作　　者：Zhanke Li Xiaoming Li Xiaoye Jin Kai Gao 

机构地区：[1]School of Earth Resources,China University of Geosciences,Wuhan 430074,China [2]Engineering Technology Innovation Center of Mineral Resources Explorations in Bedrock Zones,Ministry of Natural Resources,Guiyang 550081,China [3]No.1 Institute of Geological and Mineral Resources Survey of Henan Province,Luoyang 471023,China

出　　处：《Journal of Earth Science》2021年第1期195-207,共13页地球科学学刊（英文版）

基　　金：We acknowledge financial supports of the National Natural Science Foundation of China(Nos.41772074,41402066);the Ministry of Science and Technology of China(No.2016YFC0600104).

摘　　要：The Fudian ore field in the southern North China Craton hosts the giant Donggou porphyry Mo deposit and several Pb-Zn-Ag vein deposits. Ore genesis of the Pb-Zn-Ag deposits and their relationships with the Donggou porphyry-related system are still controversial, which further restricts the regional prospecting and exploration. The Laodaizhanggou Pb-Zn-Ag deposit in the northwest of the ore field was focused in this study, to investigate its ore-forming age and genesis, and further to explore the implications for regional prospecting of Pb-Zn-Ag and Mo. The Pb-Zn-Ag veins at Laodaizhanggou are structurally controlled by the east-striking fault zones transecting the host volcanic rocks of Proterozoic Xiong’er Group. Field observations and textural relationships indicate that there are four paragenetic stages during ore-forming process, including the quartz-pyrite veins(stage I), siderite-polymetallic sulfide veins(stage II), ankerite-polymetallic sulfide veins(stage III), and quartz-calcite veins(stage IV). Ore-related sericite 40 Ar/39 Ar dating shows that the Pb-Zn-Ag mineralization at Laodaizhanggou was formed at 124.7±1.2 Ma. Carbonate minerals(siderite, ankerite, and calcite) have δ13 CPDB values of-9.1‰ to-3.9‰ and δ18 OSMOW of 12.1‰ to 15.6‰, corresponding to calculated values for the ore fluids of-8.0‰ to-2.8‰ and 4.9‰ to 10.1‰, respectively. These isotope values are in accordance with those of magmatic fluids. Sulfide minerals at Laodaizhanggou have δ34 S values of 5.3‰ to 10.1‰, and galena separates have 206 Pb/204 Pb ratios of 17.380 to 17.458, 207 Pb/204 Pb ratios of 15.459 to 15.485, and 208 Pb/204 Pb ratios of 38.274 to 38.370. Both S and Pb isotope data of Laodaizhanggou are consistent with those of the Donggou porphyry Mo deposit and distal Sanyuangou and Wangpingxigou Pb-Zn-Ag deposits, suggesting they share a similar magmatic origin. However, the Laodaizhanggou deposit was not the distal product of the giant Donggou porphyry-related magmatic-hydrothermal system, as the fo

关 键 词：age and genesis Laodaizhanggou Pb-Zn-Ag deposit mineral prospecting Fudian ore field North China Craton 

分 类 号：P618.4[天文地球—矿床学] P618.52[天文地球—地质学]