西藏雄巴地区雄巴组火山岩地球化学特征、岩浆源区探究  

Geochemical Characteristics of Volcanic Rocks And Magmatic Origin Area of Xiongba Formation in Xiongba Area,Tibet

作　　者：朱国宝 余旭辉[1,2] 胡古月 ZHU Guo-bao;YU Xu-hui;HU Gu-yue(Regional Geological Surveying Team,BGEEMRSP,Chengdu 610213;College of Earth Sciences,Chendu University of Technology,Chengdu 610059;Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037;Key Laboratory of Mineralization and Resource Evaluation,Ministry of Natural Resources,Beijing 100037)

机构地区：[1]四川省地质矿产勘查开发局区域地质调查队,成都610213 [2]成都理工大学地球科学学院,成都610059 [3]中国地质科学院矿产资源研究所,北京100037 [4]自然资源部成矿作用与资源评价重点实验室,北京100037

出　　处：《四川地质学报》2022年第4期657-663,共7页Acta Geologica Sichuan

基　　金：西藏革吉县雄巴南1:5万4幅(H44E001014、H44E001015、H44E001016、H44E001017)区域地质调查(DD20160026)项目;班公湖—怒江成矿带铜矿多金属矿资源基地调查项目(DD20190167)联合资助。

摘　　要：在西藏革吉县雄巴南1:5万4幅区域地质调查工作中发现西藏雄巴地区大面积展布钾质-超钾质火山岩,火山岩属雄巴期。对雄巴组粗安岩及粗面岩样品进行LA-ICP-MS锆石U-Pb同位素定年,测试结果分别为17.67±0.28Ma、24.3±2.5Ma,其形成时代为中新世。通过对雄巴组火山岩岩石地球化学分析,并对雄巴组火山岩粗安岩及粗面岩岩浆源区研究,表明两类岩石(粗安岩及粗面岩)基本未遭受或仅遭受了极低程度的蚀变,两者均属钾玄岩系列,粗安岩及粗面岩物质源区可能以角闪岩为主,且粗面岩物质源区有向杂砂岩过渡的趋势。Potassium-superpotassium-volcanic rocks were distributed in Xiongba area of Tibet during the 1:50000 regional geological survey(four maps) in Geji County,Tibet.The volcanic rocks belong to Xiongba Period.LA-ICP-MS zircon U-Pb dating results of the trachyandesite and trachyte samples of the Xiongba Formation are 17.67±0.28Ma and 24.3±2.5Ma,respectively,formed in the Miocene.Based on the geochemical analysis of the volcanic rocks of the Xiongba Formation and the magmatic source of the trachyandesite and trachet of the Xiongba Formation,it is shown that the two types of rocks(trachyandesite and trachet) have not suffered or only suffered low degree of alteration.They belong to the shoshonite series,and the origin of thetrachyandesite and trachet may be mainly amphibolite.The origin of the trachet material has a transition tendency to greywacke.

关 键 词：雄巴地区 钾玄岩 地球化学特征 岩浆源区 

分 类 号：P588.14[天文地球—岩石学]