LATE CARBONIFEROUS TECTONIC REGIME TRANSITION IN EAST JUNGGAR: EVIDENCE FROM A2-TYPE RHYOLITE
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摘要: 老爷庙地区位于东准噶尔东部,是中亚造山带的重要组成部分。老爷庙流纹岩与典型A型花岗岩相似,成因类型上属A2型流纹岩,产于后碰撞环境。锆石U-Pb定年显示其形成于(311.6±3.1)Ma,属晚石炭世。综合文中数据及区域地质特征,老爷庙地区在晚石炭世已经拼贴到西伯利亚板块,进入后碰撞向板内转化的过渡期,结束了该区洋陆过渡环境。Abstract: Laoyemiao area is located in east of east Junggar, known as the important tectonic metallogenic belt of the Central Asian Orogenic Belt. Laoyemiao rhyolite is similar to the typical A-type granite, and the genetic type belongs to A2-type rhyolite, which is produced in post-collision environment. Zircon U-Pb dating shows that it was formed at (311.6±3.1)Ma in the Late Carboniferous. Based on the data and regional geological features, Laoyemiao area has been planted into the Siberian plate in the Late Carboniferous, entering the transition period from the post-collision to the intraplate transformation, and put an end to the ocean-land transition environment.
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Key words:
- east Junggar /
- Laoyemiao /
- post-collision environment /
- A2-type rhyolite /
- Late Carboniferous
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