学术论文

      西准噶尔阿克巴斯陶岩体三维形态及其地质意义

      Three-Dimensional Configuration Analysis and Its Geological Significance of Akebasitao Pluton in West Junggar

      摘要:
      西准噶尔地区广泛发育晚石炭世-二叠纪不同规模、形态各异的花岗岩体,阿克巴斯陶岩体是其中最具代表性岩体之一,但对于该岩体三维形态和侵位过程的研究尤显薄弱。基于详细的野外路线地质调查,通过对阿克巴斯陶岩体 NE、NW、SE和 SW 侧接触边界产状、接触热变质带宽度、岩脉方位和发育程度、顶垂体和围岩捕虏体发育特征的研究,揭示出岩体 NE、SE和 SW 侧与围岩呈低角度外倾接触,而岩体 NW 侧与围岩呈高角度接触。在此基础上,结合岩体出露区音频大地电磁反演结果,揭示出阿克巴斯陶岩体三维形态总体为不对称蘑菇状,岩体侵位时岩浆主要由 NW 向朝 SE 向斜向侵位,并建立了岩体的三维形态模型。阿克巴斯陶岩体三维形态的确定,揭示了西准噶尔地区晚石炭世晚期-早二叠世为后造山伸展环境。
      Abstract:
      Late Carboniferous-Early Permian post-collision plutons are extensively distributed throughout the West Junggar, Xinjiang,China,of which the Akebasitao pluton is the most distinguished one.However,investigations on the three-dimensional configuration and emplacement mechanism of the pluton remain relatively insufficient.A multidisciplinary approach,including field structure and audio magnetotelluric sounding,has been adopted for study on the Akebasitao pluton. The geological features and the audio magnetotelluric sounding exploration suggest that the pluton,with an asymmetrical mushroom-shape and slightly oblique movement of magma from NW to SE,formed in the post-orogenic extensional environ-ment.What is more,the three-dimensional configuartion of the pluton reveals that the West Junggar was of post-orogenic ex-tensional environment in the Late Carboniferous to Early Permian.This study has important implication for three-dimensional shape of those post-collision plutons that are widely developped in West Junggar.
      作者: 张攀 [1] 王国灿 [2] 肖龙 [1] 张胜业 [3] 周佩 [1] 张云 [1] 沈青强 [1]
      Author: Zhang Pan [1] Wang Guocan [2] Xiao Long [1] Zhang Shengye [3] Zhou Pei [1] Zhang Yun [1] Shen Qingqiang [1]
      作者单位: 中国地质大学全球大地构造研究中心,地球科学学院,湖北武汉 430074 中国地质大学全球大地构造研究中心,地球科学学院,湖北武汉 430074; 中国地质大学地质过程与矿产资源国家重点实验室,湖北武汉 430074 中国地质大学地球物理与空间信息学院,湖北武汉,430074
      年,卷(期): 2015, (6)
      分类号: P545
      机标分类号: P58 P59
      在线出版日期: 2015年7月15日
      基金项目: 中国地质调查局项目(No.1212011220245);新疆1∶25万铁厂沟镇幅、克拉玛依市幅区调修测(No.1212011120502).