东天山石炭纪企鹅山群火山岩岩石成因  

Petroginesis of the Carboniferous Qi'eshan Group Volcanic Rocks in the East Tianshan

作　　者：李向民[1] 夏林圻[2] 夏祖春[2] 徐学义[2] 马中平[1] 王立社[2] 

机构地区：[1]西北大学地质系,西安710069 [2]西安地质矿产研究所,西安710054

出　　处：《吉林大学学报（地球科学版）》2006年第3期336-341,390,共7页Journal of Jilin University：Earth Science Edition

基　　金：中国地质调查局地调项目(200313000063)

摘　　要：土屋矿区南北大沟企鹅山群火山岩的岩石地球化学研究表明:东天山企鹅山群火山岩主要为拉斑系列,少量为钙碱系列;岩石类型为玄武岩、玄武安山岩、英安岩和流纹岩。稀土、微量元素和Sr、Nd同位素特点揭示:该火山岩系形成于大陆裂谷环境;其源区主要为软流圈地幔,同时有岩石圈地幔源组分卷入,酸性岩浆是玄武质岩浆结晶分异的产物。Study on the petrogeochemistry of the volcanic rocks of the Qi＇eshan Group in the Nanbeidagou in the Tuwu ore area indicates that a majority of the Qi＇eshan Group volcanic rocks belongs to tholeiitic series while minority belongs to calc-alkaline series; The Qi＇eshan Group volcanic rocks consist of basalt, basaltic andesite, dacite and rhyolite. Studies on REE, trace elements and St, Nd isotopic compositions reveal that the Qi＇eshan Group volcanic rocks were formed in a continental rift setting; their source region was most likely an asthenospheric mantle with lithosphere mantle involvement; Silicic magmas were derived by fractional crystallization of the basaltic magmas.

关 键 词：企鹅山群 火山岩 地球化学岩石成因 东天山 

分 类 号：P581[天文地球—岩石学] P588.14[天文地球—地质学]