东昆仑造山带海德乌拉一带早侏罗世火山岩特征及其构造意义  

Characteristics of Early Jurassic Volcanic Rocks and Their Tectonic Significance in Haidewula, East Kunlun Orogenic Belt, Qinghai Province

作　　者：朱云海[1] 朱耀生 林启祥[1] 王国灿[1] 

机构地区：[1]中国地质大学地球科学学院,湖北武汉430074 [2]青海省地质调查研究院,青海西宁810012

出　　处：《地球科学（中国地质大学学报）》2003年第6期653-659,共7页Earth Science-Journal of China University of Geosciences

基　　金：中国地质调查局1:25万阿拉克湖幅区域地质调查项目(No.19991300004021);高等学校全国优秀博士论文作者专项资金项目(No.200228).

摘　　要：对东昆仑造山带哈拉郭勒地区海德乌拉山一带的火山岩进行了较系统的岩石学、地球化学研究.在实测剖面研究、同位素年代学及区域地层对比的基础上,把该套火山岩厘定为早侏罗世火山岩.火山岩岩石组合主要为基性和酸性熔岩,成分上具典型的裂谷"双峰式"特征,缺乏中性岩石,基性火山岩碱性程度较高,酸性火山岩主要为钙碱性岩石,其形成的构造环境为俯冲过程中在岛弧靠近大陆一侧弧后拉张形成的陆内裂谷的构造环境.This article studies systematically the petrology and geochemistry of the volcanic rocks of Haidewula area, east Kunlun orogenic belt, Qinghai Province. Based on the section, isotopic dating and regional strata contrasting, it has determined that this suit of volcanic rocks should be Early Jurassic. These volcanic rocks are mainly basic and acid, showing typical 'Bi-model' character of rifting, but lacking in intermediate rocks. The basic rocks have a higher alkali degree, while the acid rocks mainly belong to calc series. The volcanic rocks are formed in the rift tectonic environment, split from inner continent among the post orogeny.

关 键 词：东昆仑造山带 早侏罗世 裂谷 火山岩 

分 类 号：P58[天文地球—岩石学]