西藏查个勒铅锌钼铜矿床H-O-S-Pb同位素特征及成矿指示——兼与念青唐古拉成矿带中-东段铅锌(铜钼)矿床对比  

H-O-S-Pb Isotopic Compositions of the Chagele Pb-Zn-Cu-Mo Deposit, Tibet: Implications for the Ore-forming Processes and Comparison with Pb-Zn(Cu-Mo) Deposits in Middle-east Segment of the Nyainqentanglha Metallogenic Belt

作　　者：张永超[1] 郑有业[1,2] 高顺宝[1] 姜军胜 田坎 伍登浩 姜晓佳[3] 张树志 栾康 ZHANG Yongchao1, ZHENG Youye1, 2, GAO Shunbao1, JIANG Junsheng3, TIAN Kan3, WU Denghao4, JIANG Xiaojia3, ZHANG Shuzhi5 and LUAN Kang1(1. Institute of Geological Survey, China University of Geosciences （Wuhan）, Wuhan 430074, Hubei, China; 2. State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences （Beijing）, Beijing 100083, China; 3. Faculty of Earth Resources, China University of Geosciences （Wuhan）, Wuhan 430074, Hubei, China; 4. Guizhou Water Technology Co., Ltd, Guiyang 550000, Guizhou, China; 5. School of the Earth Sciences and Resources, China University of Geosciences （Beijing）, Beijing 100083, China)

机构地区：[1]中国地质大学(武汉)地质调查研究院,湖北武汉430074 [2]中国地质大学(北京)地质过程与矿产资源国家重点实验室,北京100083 [3]中国地质大学(武汉)资源学院,湖北武汉430074 [4]贵州黔水科技有限责任公司,贵州贵阳550000 [5]中国地质大学(北京)地球科学与资源学院,北京100083

出　　处：《大地构造与成矿学》2018年第3期467-479,共13页Geotectonica et Metallogenia

基　　金："青藏高原拉萨-羌塘地块构造热年代学填图和矿产调查"项目(DD2016027);"青藏高原大陆碰撞斑岩铜-钼-金成矿系统结构与形成机制"项目(2016YFC0600305)联合资助

摘　　要：查个勒铅锌钼铜矿床位于念青唐古拉铅锌银铁铜成矿带西段南缘,为查明其成矿物质来源及矿床成因,对该矿床开展了系统的H、O、S、Pb同位素研究,并与念青唐古拉成矿带中-东段典型铅锌(铜钼)矿床进行对比。查个勒矿床石英H、O同位素(δD值介于-189‰～-157‰之间,δ^(18)O_(H_2O)值介于-2.2‰～2.9‰之间)指示其成矿流体主要由岩浆水与大气降水混合组成。矿区北部铅锌矿体硫化物δ^(34)S值为-5.6‰～-0.8‰,均值为-3.7‰,显示岩浆硫和地层硫混合的特征。矿区南部(铜)钼矿体硫化物δ^(34)S值为1.1‰～2.6‰,均值为1.8‰,显示岩浆硫的特征。矿石硫化物和花岗斑岩全岩^(208)Pb/^(204)Pb,^(207)Pb/^(204)Pb,^(206)Pb/^(204)Pb的比值分别为38.988～39.269、39.002～39.559,15.657～15.747、15.643～15.664,18.614～18.688、18.663～19.058。矿石硫化物与花岗斑岩的Pb同位素特征相似,均表现出上地壳Pb源的特征,推测成矿物质主要来自上地壳岩浆源。查个勒矿床H、O、S、Pb同位素特征与中-东段典型铅锌(铜钼)矿床相似,表明念青唐古拉成矿带铅锌(铜钼)矿床成矿流体及成矿物质来源一致。作者认为查个勒矿床是一个受岩浆和构造共同控制的斑岩型(铜)钼+矽卡岩型-热液脉型铜铅锌矿床,在念青唐古拉成矿带,自西向东分布有多处斑岩型(铜)钼矿+矽卡岩型-热液脉型(铜)铅锌矿矿集区。The Chagele is a typical Pb-Zn-Cu-Mo deposit located in the western Nyainqentanglha Pb-Zn-Ag-Fe-Cu metallogenic belt（NPMB） that immediately north of the Gangdese porphyry copper belt, Tibet. The deposit contains three ore types： the porphyry（Cu） Mo ores occur as thin veins hosted in the granite porphyry; the skarn（Cu） Pb-Zn type ores are of vein-type or lenticular-type mainly occurring in the external contact zone and interstratified crack zone; and the hydrothermal vein Pb-Zn type ores are controlled by the NNE-striking faults and situated in the structural fractured zones and the up walls of fault zones. The（Cu） Pb-Zn ores consist mainly of galena, sphalerite, chalcopyrite, pyrite, malachite, showing automorphic granular, hypautomorphic to allotriomorphic granular and metasomatic-relict textures, and exhibiting mainly veined, banded, disseminated and massive structures. Hydrothermal alteration includes skarnization, silicification and limonitization. The（Cu） Mo ores consists mainly of chalcopyrite and molybdenite, and minor pyrite. The（Cu） Mo ores are characterized by scaly texture, veinlet and massive structures. It has reserves of 0.38 Mt Pb, 0.6 Mt Zn and 110.1 t Ag, with average grade of 2.08%, 3.29% and 6.07 g/t, respectively, and is considered as a deposit with huge ore-prospecting potential in western of NPMB. However, the ore-forming material and genesis of the Chagele deposit are still not clear. This paper systematically investigated the H, O, S and Pb isotopes of the Chagele deposit and compared it with the other Pb-Zn（Cu-Mo） deposits in the middle-east segment of NPMB. Isotopic geochemical analyses showed that the fluids have δ^（18）O values of-2.2‰ to 2.9‰ and δD values of -189‰ to -157‰, respectively, indicative of mixing between magmatic and meteoric waters. The bimodal distribution of δ34S values for sulfides（-5.6‰ to -0.8‰, the average：-3.7‰ and 1.1‰ to 2.6‰, the average： 1.8‰） indicated that sulfur of the ores were derived from bo

关 键 词：H、O、S、Pb同位素 成矿物质 查个勒铅锌钼铜矿床 念青唐古拉成矿带 

分 类 号：P595[天文地球—地球化学] P612[天文地球—地质学]