西藏班公湖-怒江成矿带南缘鑫龙金矿的发现及意义  

Discovery and significance of Xinlong gold deposit in southern margin of Ban⁃gonghu-Nujiang metallogenic belt

作　　者：陈伟[1] 宋扬[1] 刘青枰 张建珍 孙渺 宋壮壮 刘腾飞 王强 俞嘉嘉 李阳 刘畅[2] CHEN Wei;SONG Yang;LIU QingPing;ZHANG JianZhen;SUN Miao;SONG ZhuangZhuang;LIU TengFei;WANG Qiang;YU JiaJia;LI Yang;LIU Chang(MNR Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China;School of Earth Science and Resource,China University of Geosciences,Beijing 10083,China;Regional Geological Survey Institute of Hebei Province,Langfang 065000,Hebei,China;College of Earth Science,Chengdu University of Technology,Chengdu 610059,Sichuan,China)

机构地区：[1]中国地质科学院矿产资源研究所,自然资源部成矿作用和资源评价重点实验室,北京100037 [2]中国地质大学(北京)地球科学与资源学院,北京100083 [3]河北省区域地质调查院,河北廊坊065000 [4]成都理工大学地球科学学院,四川成都610059

出　　处：《矿床地质》2022年第6期1245-1257,共13页Mineral Deposits

基　　金：国家自然科学基金项目(编号:41902099);中国地质调查局地调项目(编号:DD20221684);中国地质科学院矿产资源研究所基本科研业务费专项经费(编号:KK2214)联合资助。

摘　　要：西藏鑫龙金矿位于西藏那曲市尼玛县,是中国地质科学院矿产资源研究所在中国地质调查局1∶5万矿产地质调查项目支持下发现的一处具有勘探潜力的金矿床。文章通过野外详细的1∶1万矿区地质填图、激电测深测量、山地工程以及室内详细的岩相学及矿相学研究,得出以下结论:鑫龙金矿产于班公湖-怒江成矿带南缘中拉萨地体中部则弄群火山岩中,主要受北北西向断裂控制,其矿化和蚀变特征与典型的高硫型浅成低温热液金矿的特征类似。目前矿区共圈定4条矿体,其矿石类型主要为团块状、稠密-稀疏浸染状和角砾状矿石,矿石中金属矿物主要为黝铜矿族矿物,其中包括锌锑黝铜矿、锌砷黝铜矿和铁砷黝铜矿,其他金属矿物有黄铁矿、黄铜矿、辉硒铋矿、斑铜矿、铅矾、自然金、硒银矿等。鑫龙矿床发育的蚀变主要为硅化和中-高级泥化,硅化表现为则弄群扎列拿组火山岩被后期火山热液交代发生硅化而形成的硅质蚀变岩石,在断裂通过的构造破碎带中硅化强烈,发育有孔洞状石英;中-高级泥化主要表现为叶蜡石化和高岭土化。激电测深测量和山地工程揭示出鑫龙金矿具有优越的成矿地质条件以及巨大的成矿潜力,综合区域成矿地质背景认为拉萨地体中部,沿着申扎-措勤-革吉-狮泉河一带可能存在一条和陆缘弧火山岩有关的浅成低温热液型金矿带,鑫龙金矿的发现将为藏北的岩金矿找矿工作开启新的篇章。The Xinlong gold deposit is located in Niyma County,Naqu area,Tibet.It is discovered by the Institute of Mineral Resources,Chinese Academy of Geological Sciences through the 1∶50000 mineral geological survey.Ore bodies occur in the Zenong Group volcanic rocks in the middle section of the central Lhasa terrane and are structurally controlled by the NNW-striking faults.Four ore bodies have been found with cloddy,dense-sparse,disseminated and breccia structures.Ore minerals are mainly tetrahedrite group minerals,including zinc-antimony tetrahedrite,zinc-arsenic tetrahedrite and iron-arsenic tetrahedrite.Other ore minerals include pyrite,chalcopyrite,nevskite,bornite,anglesite,natural gold,silver-gold bearing selenide,etc.The alterations of the deposit are dominated by silicification as well as middle-and high-graded argillization.The Zaliela Formation volcanic rocks of Zenong Group are silicified by later hydrothermal fluid with vuggy quartz in some fractured zones.The middle-and high-graded argillization are characterized by pyrophyllitization and kaolinization.Controlled by 1:10000 geological mapping,IP sounding and trial trench in mining area,the Xinlong gold deposit displays great metallogenetic potentiality.Combined with the regional metallogenic geological setting,we suppose that a potential epithermal gold belt probably exists in the middle of Lhasa terrane.The discovery of the Xinlong gold deposit opens a new chapter for the gold prospecting in northern Tibet.

关 键 词：地球化学 浅成低温热液金矿 鑫龙金矿 中拉萨地体 班公湖-怒江成矿带 

分 类 号：P618.51[天文地球—矿床学]