论文部分内容阅读
研究区位于华北地块北缘西段,是解析中亚造山带构造演化的关键部位。本文在野外地质调查基础上,应用TIMS锆石U-Pb测年法对东升庙一带主要花岗—闪长质侵入岩体进行分析,完善了原有工作成果。证实了该区存在太古代结晶基底((2 619±18)Ma、(2 563±21)Ma),并于古元古代中晚期(2.0Ga)经历了一次强烈的碰撞造山运动,造成了闪长质与花岗质岩浆侵位,以及1.9Ga的变质事件。而后又经历了中元古代伸展裂解、石炭纪中晚期洋壳俯冲((304±3.4)Ma、(320.5±2.9)Ma)和二叠纪—三叠纪碰撞拼合((227.6±4)Ma、(246±2.5)Ma)3个重要的构造事件阶段,并伴有大规模岩浆侵入。
The study area is located in the western segment of North margin of North China block and is the key part for analyzing the tectonic evolution of the Central Asian orogenic belt. Based on the field geological survey, this paper analyzes the main granodiorite-dioritic intrusions in the Dongsamiao area by TIMS zircon U-Pb dating, and improves the original work. It is confirmed that Archean crystalline basement ((2 619 ± 18) Ma, (2 563 ± 21) Ma) exists in this area and experienced a strong collision orogeny in the middle and late Paleoproterozoic (2.0Ga) Long and granitic magma emplacement, and 1.9Ga metamorphic events. Later, it experienced Mesozoic extensional pyrolysis. During the Late Carboniferous, the oceanic crust subduction ((304 ± 3.4) Ma, (320.5 ± 2.9) Ma) and Permian-Triassic collision assemblage ((227.6 ± 4) Ma) (246 ± 2.5) Ma) are three important tectonic event stages accompanied by large-scale magmatic intrusion.