新疆阿拉套山花岗岩类的特征及成因研究  

GEOCHEMICAL CHARACTERISTICS AND GENESIS OF GRANITOIDS FROM ALATAW MOUNTAIN,XINJIANG, CHINA

作　　者：周泰禧[1] 陈江峰[1] 陈道公[1] 李学明[1] 

机构地区：[1]中国科学技术大学

出　　处：《地球化学》1995年第1期32-42,共11页Geochimica

基　　金：国家自然科学基金;国家305项目

摘　　要：从岩石化学、ＲＥＥ、Ｓｒ、Ｎｄ、Ｏ、Ｐｂ同位素等角度讨论了新疆阿拉套山花岗岩类地球化学特征。结果表明本区存在两个系列的花岗岩，东部以Ｉ型为主，西部Ｓ型花岗岩占主导地位。同时，本区岩石的Ｓｒ、Ｎｄ、Ｏ同位素组成可以用ＡＦＣ模式加以解释，即它们是由幔源岩浆经过同化地壳围岩同时结晶分异形成。当然也不排除幔源组分较多的优地槽不成熟沉积物发生重熔形成的可能。The geochemical characteristics, including those of major elements, REE, Sr, Nd,O and Pb isotopes, of the granitoids from the southern slope of Alataw Mountain,Xinjiang, indicate that there are two series of granitoids in the area. Granites from the western part show proximity to S-type those. Their major source materials are from the crust, and the magma reservoir may be shallow in the crust. Granites from the east have the characteristics similar to I-type and their formation wascontrolled by the mantle-derived materials.The granites have a εNd value of 2.2-3.2, and their Sr, Nd and Pb isotopes match the AFC model that mantle-derived magma assimilates crustal country rocks,and then crystallize.The granites also show systematic geochemical changes with distance from Aibi Lake fault, which suggests that the fault be a plate boundary fault, representing the main tectonic orientation of the region.

关 键 词：花岗岩类 幔源组分 岩石成因论 新疆 

分 类 号：P588.121[天文地球—岩石学]