西藏班公湖-怒江结合带中段去申拉组火山岩年代学及勘查找矿方向  

Geochronology and Ore Prospecting Potential of Qushenla Formation in Middle Segment of Bangong Co-Nujiang Suture Zone,Tibet

作　　者：邓世林[1] 林彬[2] 张海潮 阿旺仁增 王腾 胡志中 邹兵[5] 张忠坤 杨征坤 刘振宇[7] Deng Shilin;Lin Bin;Zhang Haichao;Awang Renzeng;Wang Teng;Hu Zhizhong;Zou Bin;Zhang Zhongkun;Yang Zhengkun;Liu Zhenyu(No.605 Party of Sichuan Metallurgical Geology Bureau,Meishan 620860,China;MNR Key Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resources of Chinese Academy of Geological Sciences,Beijing 100037,China;No.5 Geological Party of Tibet Bureau of Geology and Mineral Exploration and Development,Golmud 810600,China;MNR Key Laboratory for Sedimentary Basin and Oil and Gas Resources,Chengdu 610081,China;School of Earth Sciences and Resources,China University of Geosciences,Beijing 100083,China;Tibet Huatailong Mining Development Co.Ltd.,Lhasa 850000,China;Geological Survey Institute of Jilin Province,Changchun 130102,China)

机构地区：[1]四川省冶金地质勘查局六○五大队,四川眉山620860 [2]中国地质科学院矿产资源研究所自然资源部成矿作用与资源评价重点实验室,北京100037 [3]西藏自治区地质矿产勘查开发局第五地质大队,青海格尔木810600 [4]自然资源部沉积盆地与油气重点实验室,四川成都610081 [5]中国地质大学地球科学与资源学院,北京100083 [6]西藏华泰龙矿业开发有限公司,西藏拉萨850000 [7]吉林省地质调查院,吉林长春130102

出　　处：《地球科学》2020年第3期776-788,共13页Earth Science

基　　金：中国地质调查局二级项目(Nos.DD20160026,DD20160026);国家重点研发-深地专项(No.2018YFC064101);中国地质科学院基本科研业务费(No.SYSCR2019-02);西藏自治区科技计划项目(No.XZ201901-GB-24);国家自然科学基金项目(No.41902097).

摘　　要：作为班公湖-怒江结合带最为重要的火山岩沉积地层之一,去申拉组一直缺乏精细的年代学研究和找矿潜力的分析.基于班-怒结合带中段尼玛县北部长期的矿产地质调查工作,对热过勒、饿蒙勒、阿俄作登等地区的去申拉组进行了详细解剖,并利用锆石U-Pb定年精细厘定区内去申拉组中英安岩、安山岩的结晶时限分别为106.2±1.3 Ma、107.7±1.4 Ma,属于早白垩世火山活动的产物.同时,区内1︰5万水系沉积物异常以及实地调查揭示,阿俄作登和饿蒙勒地区存在良好铜、金、银组合异常,初步揭露1条高品位的矿化体.结合区域成矿作用背景分析,认为该区存在良好的斑岩-浅成低温热液型铜多金属成矿系统的找矿潜力.班公湖-怒江结合带去申拉火山沉积地层的形成时限的精确厘定,为区域基础地质格架的构建提供了直接证据;而其矿化信息的首次揭露,为该带早白垩世大面积覆盖的火山岩地区的勘查找矿工作指明了新方向.The Qushenla Formation is one of the most important volcanic strata in Bangong Co-Nujiang suture zone,however,there is no detailed geochronology and prospecting potential study.Based on long-term ore geological survey in Nima County,we do a detailed study on the Qushenla Formation in Reguole,Emengle,Aezuodeng areas,and date the dacite and andesite in Qushenla Formation with U-Pb age of zircons.They are 106.2±1.3 Ma and 107.7±1.4 Ma,respectively,as the result of Early Cretaceous magmatism.At the same time,good Cu,Au,Ag anomalies and one high-grade copper-bearing mineralized body were found in Aezuodeng and Emengle areas,according to the 1︰50000 stream sedimentary analysis.Given the regional metallogenic background,we suggest this area is a good prospecting target for porphyry-epithermal copper system exploration.The precise geochronology of Qeshenla Formation gives the direct evidence for the framework building of regional strata.The first discovery of the mineralization in Qushenla Formation reveals a new direction for the further exploration and prospecting in the large area of the Bangong Co-Nujiang suture zone covered volcanic rocks.

关 键 词：去申拉组 地质年代学 斑岩-浅成低温热液 班公湖-怒江结合带 西藏 

分 类 号：P597[天文地球—地球化学]