新疆萨吾尔地区两类花岗岩Nd、Sr、Pb、O同位素特征  

Nd, Sr, Pb, O Isotope Characteristics of Two Types Granites in the Sawuer Region,Xinjiang

作　　者：袁峰[1] 周涛发[1] 杨文平 何立新 范裕[1] 谭绿贵[1] 岳书仓[1] 

机构地区：[1]合肥工业大学资源与环境工程学院,230009 [2]新疆地质勘查局第四地质大队,阿勒泰836500

出　　处：《地质学报》2006年第2期264-272,共9页Acta Geologica Sinica

基　　金：国家重点基础研究发展规划项目(编号2001CB409800);安徽省优秀青年科技基金项目(编号04045063)资助的成果。

摘　　要：新疆西准噶尔萨吾尔地区森塔斯岩体和沃肯萨拉岩体为I型花岗岩,侵入于早石炭世末,具有偏碱性特点,形成于后碰撞阶段的伸展期或挤压—伸展转变期;阔依塔斯岩体和恰其海岩体为A2型花岗岩,侵入于早二叠世初,形成于后碰撞阶段伸展期张性构造环境中。I型花岗岩和A型花岗岩的Nd、Sr、Pb同位素特征相似,显示出幔源特征,它们是同源岩浆不同演化阶段的产物。两类花岗岩在O同位素以及稀土元素特征上存在明显差异。西准噶尔萨吾尔地区I型花岗岩(森塔斯岩体和沃肯萨拉岩体)以及A型花岗岩(阔依塔斯岩体和恰其海岩体)的发育,进一步证实了晚古生代区内地壳的垂向增生作用。对比研究表明,可以将西准噶尔萨吾尔地区的A型花岗岩归入东准噶尔乌伦古富碱火成岩带。The Sentasi and the Wokensala intrusions are Ⅰ type granites in west Zhungeer Sawuer region, Xinjiang. They are the partial alkali rocks and formed at the late of Early Carboniferous in the extendable period or compressible to extendable period of the post-collisional phase. The Kuoyitasi and the Qiaqihai intrusions are A2-type granites. They formed at the beginning of Early Permian during the extendable period of the post-collisional phase. The Nd,Sr,Pb isotope characteristics of Ⅰ type granites are similar to those of A type granites. The Ⅰ type and A type granites came from the mantle magma. They were the results of different evolutive phase of the same source magma. The O isotope and the REE characteristics of Ⅰ type and A type granites were different distinctly. The Ⅰ type and A type granites from mantle sources formed at late Palaeozoic in west Zhungeer Sawuer region can further confirm the vertical addition of the continental crust. The A type granites in west Zhungeer Sawuer region can belong to the Ulungur alkali granites belt in east Zhungeer.

关 键 词：花岗岩 同位素 后碰撞 萨吾尔 新疆 

分 类 号：P588.121[天文地球—岩石学] P618.510.4[天文地球—地质学]