阿尔泰造山带南缘富蕴后造山线形花岗岩体锆石U-Pb年龄及其地质意义  

TIMS U-Pb zircon ages of Fuyun post-orogenic linear granite plutons on the southern margin of Altay orogenic belt and their implications

作　　者：童英[1] 洪大卫[1] 王涛[1] 王式洸[2] 韩宝福[2] 

机构地区：[1]中国地质科学院地质研究所,北京100037 [2]北京大学地球与空间科学学院,北京100871

出　　处：《岩石矿物学杂志》2006年第2期85-89,共5页Acta Petrologica et Mineralogica

基　　金：国家重大基础研究规划项目(2001CB409802)国际合作基金(40210647)国家自然科学基金(40472101;49772105)

摘　　要：阿尔泰造山带南缘发育一系列后造山花岗岩体。富蕴南额尔齐斯断裂带中发育具有片麻理的黑云母花岗岩体,其中还侵入有未变形的黑云母花岗岩体。本文对这两个岩体进行了 TIMS 法锆石 U-Pb 测年,结果分别为 281±5 Ma(变形岩体)和275±2 Ma(不变形岩体),显示其为后造山花岗岩体。该研究表明,阿尔泰造山带在281± 5 Ma 时仍存在一定规模的后造山剪切作用,275±2 Ma 之后变形作用开始变弱。A series of post-orogenic granite plutons occur on the southern margin of Altay orogenic belt. A gneissic deformed granitic pluton occurs in the Ertix faulted zone to the south of Fuyun, intruded by an underformed granitic pluton. The former pluton is dated by U-Pb TIMS method at 281 ± 5 Ma and the latter at 275 ± 2 Ma. These data indicate that shearing deformation still took place to some extent along Ertix zone during ca. 280 275 Ma in the post-orogenic period. The deformation probably ended or became much weaker after 275 ± 2 Ma.

关 键 词：后造山花岗岩 锆石年龄 变形 阿尔泰造山带 富蕴 

分 类 号：P588.121[天文地球—岩石学] P597.3[天文地球—地质学]