川西北碧口地块老河沟岩体和筛子岩岩体地球化学特征及其构造环境
DOI:
作者:
作者单位:

作者简介:

通讯作者:

中图分类号:

基金项目:

注:本文为国家自然科学基金项目(编号 40972136、40572121、40234041)和教育部科学技术研究重点项目(编号 104175)资助的成果。


Geochemical Features and Tectonic Setting of the Laohegou Granite and the Shaiziyan Granite in Bikou Block,in Northwest Sichuan
Author:
Affiliation:

Fund Project:

  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • |
  • 资源附件
  • |
  • 文章评论
    摘要:

    老河沟岩体和筛子岩岩体位于碧口地块西南部。岩体的SiO2(69.89%~71.69%)和Al2O3(15.01%~16.25%)含量均很高,A/CNK在1.04~1.12之间,为硅和铝过饱和类型,属典型的强过铝质花岗岩。稀土元素总量(∑REE)为33.13×10-6~150.42×10-6,稀土元素配分曲线呈右倾型,具有弱的负铕异常。高场强元素(Ta、Nb、Ti等)具有明显的负异常,大离子亲石元素(Rb、Ba、Sr等)具有明显的正异常。岩体可能是以杂砂岩成分为主的沉积岩部分熔融形成的花岗质岩浆上升侵位过程中形成的,是一种典型的壳源成因类型。老河沟岩体和筛子岩岩体具有后碰撞岩浆活动的特征,是印支期华北和扬子地块碰撞导致地壳加厚环境下下地壳部分熔融的产物,形成于同碰撞(挤压环境)向碰撞后(伸展环境)转化阶段,为后造山花岗岩类。

    Abstract:

    The Louhegou granite and the Shaiziyan granite,located in southern margin of Bikou block. The data of occurrence,petrography and geochemical are reported,the source and tectonic setting of the granite are discussed in this paper. The results show that the Louhegou granite and the Shaiziyan granite have high SiO2(69.89%~71.69%),and Al2O3 composition, A/CNK=1.04~1.12. It is a type with supersaturation of Al and Si,a typical strongly peraluminous granites. The ∑REE has the range of 33.13×10-6~150.42×10-6, REE diagram shows rightward incline and obvious Eu negative abnormity. The trace elements geochemistry was characterized by evidently negative anomaly of Ta,Nb,Ti,etc positive anomaly of Rb, Ba,Sr. The Louhegou granite and the Shaiziyan granite show postcollisional granitic characteristics. These rocks are postorogenic granite,and are typical crust source petrogenesis. These granites mass are interpreted as a kind of syncollisional granites resulted from the crustal thickening caused by the collision between the North China massif and Yangtze massif during the Indosinian. These rocks were transitional environment of compressional orogeny and extensional structure.

    参考文献
    相似文献
    引证文献
引用本文

李佐臣,裴先治,丁仨平,刘战庆,李瑞保,孙雨,冯建赟,张亚峰.2010.川西北碧口地块老河沟岩体和筛子岩岩体地球化学特征及其构造环境[J].地质学报,84(3):343-356.
LI Zuochen, PEI Xianzhi, DING Saping, LIU Zhanqing, LI Ruibao, SUN Yu, FENG Jianyun, ZHANG Yafeng.2010. Geochemical Features and Tectonic Setting of the Laohegou Granite and the Shaiziyan Granite in Bikou Block,in Northwest Sichuan[J]. Acta Geologica Sinica,84(3):343-356.

复制
分享
文章指标
  • 点击次数:
  • 下载次数:
  • HTML阅读次数:
  • 引用次数:
历史
  • 收稿日期:2009-02-12
  • 最后修改日期:2009-07-15
  • 录用日期:
  • 在线发布日期: 2010-03-24
  • 出版日期: