杨硕;向树元;苏英明;

• 1:中国地质大学(武汉)地球科学学院
• 2:新疆地质调查院
• 3:中国地质大学(武汉)地质调查院
• 4:西安地质矿产勘查开发院

摘要(Abstract)：

林子宗火山岩在冈底斯带上广泛发育,其中帕那组火山岩的形成时代、构造背景和成因都存在一定争议。对林周地区帕那组火山岩进行了年代学和岩石地球化学研究,结果表明,研究区火山岩以流纹岩和英安岩为主,w(SiO2)极高,表现由高钾钙碱性系列向钾玄岩系列过渡的特征。帕那组火山岩微量元素地球化学特征显示LREE、LILE富集,HFSE亏损,Eu负异常,与岛弧火山岩地球化学特征相似。此外,帕那组流纹岩LA-ICP-MS锆石U-Pb年龄为(51.3±0.7)Ma,是目前为止冈底斯带中东段中的最老年龄。帕那组火山岩形成于后碰撞背景之下,其岩浆为地壳源区的部分熔融作用所形成。

关键词(KeyWords)： 帕那组;LA-ICP-MS;锆石U-Pb年龄;岩石地球化学;林周;西藏

Abstract:

Keywords:

基金项目(Foundation): 中国地质调查局项目(1212011221066;1212011121224)

作者(Author): 杨硕;向树元;苏英明;

Email:

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