内蒙古扎拉格阿木铜多金属矿床H、O、S、Pb同位素组成及矿床成因  

The H,O,S and Pb isotopic compositions and genesis of the Zhalageamu copper polymetallic deposit in Inner Mongolia,China

作　　者：刘怀金 许辉 张旭柱 牛兴国 邱广义 李源 郭俊凤 祝贺 邢志军 李志刚 LIU Huai-jin;XU Hui;ZHANG Xu-zhu;NIU Xing-guo;QIU Guang-yi;LI Yuan;GUO Jun-feng;ZHU He;XING Zhi-jun;LI Zhi-gang(Inner Mongolia Nonferrous Geological Mining(Group)Co.,Ltd,Hohhot 010010,China)

机构地区：[1]内蒙古有色地质矿业(集团)有限责任公司,呼和浩特010010

出　　处：《矿物岩石地球化学通报》2023年第3期521-532,共12页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：内蒙古地勘基金资助项目(2015-01-KY02)。

摘　　要：内蒙古扎拉格阿木铜多金属矿床是近年来在大兴安岭中南段西坡发现的中大型铜多金属矿床。矿床产出于二叠纪花岗闪长岩体与中二叠统哲斯组外接触带,矿体受北东向断裂构造控制,矿石矿物主要为黄铁矿、黄铜矿、毒砂、闪锌矿、方铅矿和银黝铜矿等。本文通过H、O、S和Pb同位素组成的研究,试图查明该矿床成矿流体演化特征与成矿物质来源,进一步探讨矿床成因。结果显示,金属硫化物的δ^(34)S值为-4.5‰~0.2‰,金属硫化物^(206)Pb/^(204)Pb、^(207)Pb/^(204)Pb、^(208)Pb/^(204)Pb分别为18.663~18.040、15.655~15.528、37.992~38.709;成矿流体的δ^(18)O水值为-8.5‰~-7.5‰,δD_(V-SMOW)值为-115.5‰~-98.1‰。结合大兴安岭中南段构造-岩浆演化背景认为,扎拉格阿木铜多金属矿床成矿流体主要来源于地幔,上升过程中有大气降水的加入;成矿物质具有壳幔混合源的特征,矿床属于受断裂构造控制的岩浆热液型成因。The Zhalageamu copper polymetallic deposit in Inner Mongolia is a medium-large copper polymetallic deposit discovered in the west slope of the central-southern part of the Great Hinggan Mountains in recent years.The deposit occurred in the outer contact zone between the Permian granodiorite and the Middle Permian Zhesi Formation.The ore body distribution is controlled by the NE trending fault.The ore minerals are mainly pyrite,chalcopyrite,arsenopyrite,sphalerite,galena,and silver tetrahedrite.In this paper,through the study of hydrogen,oxygen,sulfur and lead isotope compositions,we have tried to find out the evolution characteristics of the ore-forming fluid and the source of ore-forming materials,and further to explore the genesis of the deposit.The results show that the δ^(34)S values of metal sulfides are-4.5‰~0.2‰,and the ^(206)Pb/^(204)Pb,^(207)Pb/^(204)Pb and ^(208)Pb/^(204)Pb values of metal sulfides are 18.663~18.040,15.655~15.528,37.992~38.709,respectively.The δ^(18)O and δD_(V-SMOW) values of the ore-forming fluid vary from-8.5‰to-7.5‰and from-115.5‰to-98.1‰,respectively.Combined with the tectonic-magmatic evolution background of the central-southern part of the Great Hinggan Mountains,it is considered that the ore-forming fluid of the Zalageamu copper polymetallic deposit was mainly derived from the mantle,with minor meteoric water added in the ascending process.The ore-forming materials have characteristics of the crust-mantle mixed source.The deposit belongs to the fracturecontrolled magmatic hydrothermal one.

关 键 词：H、O、S、Pb同位素 矿床成因 铜多金属矿 扎拉格阿木 大兴安岭中南段 

分 类 号：P597[天文地球—地球化学]