西藏措勤地区年波组岩石地球化学特征  

Geochemical characteristics of Nianbo formation at Cuoqin county,Tibet

作　　者：毛素斌[1] 吴旭铃[1] 孙国发 

机构地区：[1]中国地质大学 [2]江西省地质调查院,江西南昌330201

出　　处：《资源调查与环境》2005年第4期235-243,共9页Resources Survey & Environment

基　　金：中国地质调查局1:250000<邦多区>;<措麦区>幅区域地质调查项目资助

摘　　要：林子宗群年波组为始新世火山岩地层,岩性主要为一套中—酸性火山熔岩、火山碎屑岩,局部夹淡水灰岩。野外地质调查和室内岩石学、岩石地球化学等综合研究成果显示这些岩石属钙碱性系列岩石,不相容元素K、Rb、Ba、Th强烈富集和Nb、Sr、P、Ti等元素明显亏损等特征,且明显受区域断裂构造控制,与区域构造演化有密切的内在联系。研究这一地史时期的火山岩的分布、产状、岩石学、岩石地球化学和同位素年代学,对于进一步认识青藏高原的形成和隆升不仅具有重要的科学意义,而且将为探寻与火山活动有关的矿产资源提供基础地质资料。Nianbo formation of Lingzizhong group is regarded as the stratum of Eocene Epoch. It chiefly consists of a set of intermediate-acid lava and pyroclastic rock, partly containing flesh water limestone. Based on the field geological investigation and the indoor synthetic research of its petrology, lithogeochemisty,the results show these rocks belong to calc-alkali rock and characterized by rich in incompatible K,Rb,Ba,and Th and depleted in Nb,Sr,P,T. They are evidently controlled by the regional structure and have a close relation with the regional structure evolution. It not only shows important scicncc significance for studying Qinghai-Tibet plateau＇s formation and risen,but also provides basis geologic information for finding mineral resources related with volcanic activity in research the distribution, attitude, petrology, neurochemistry and isotopic geochronology of the volcano rocks in the period.

关 键 词：年波组 林子宗群 区域构造演化 西藏 

分 类 号：P588[天文地球—岩石学]