秦岭-大别造山带中几条重要构造带的特征及其意义  

The research on deformation features of some structural zones in the Qinling-Dabieshan orogenic belt

作　　者：宋传中[1] 张国伟[2] 任升莲[1] 李加好[1] 黄文成[1] 

机构地区：[1]合肥工业大学资源与环境学院,安徽合肥230009 [2]西北大学大陆动力学国家重点实验室,陕西西安710069

出　　处：《西北大学学报（自然科学版）》2009年第3期368-380,共13页Journal of Northwest University（Natural Science Edition）

基　　金：国家自然科学基金资助项目(40372097,40772131);中石化南方海相基础研究基金资助项目(20060902)

摘　　要：目的研究秦岭—大别造山带内几条重要构造带的构造变形特征,以探讨其动力学过程。方法通过该造山带中各构造带的几何学、运动学特征研究,分析板块构造体系向陆内构造体系转换和大陆动力学体系演化等地质过程。结果①洛栾构造带是二郎坪弧后盆地与华北板块南缘的陆内构造拼合带,形成于365 Ma±,挤压方向为240→60°;②商丹断裂带在260 Ma±形成,挤压方向为220→40,°以压扁作用为主,正花状构造,显示出板块碰撞带的构造特征;③襄广断裂带是扬子板块在220 Ma±,由185→5°方向与大别造山带斜向汇聚的结果;④殷马断裂带为一条右行平移的韧性剪切带;⑤武穴构造对接带是大别造山带南缘与扬子板块北缘的构造复合带,是在140 Ma±扬子板块总体由S→N挤压所致;⑥宜鲁构造带是东秦岭造山带北界,为S→N逆冲的叠瓦状推覆构造,上地壳缩短率为52%;⑦郯庐断裂带是秦岭—大别造山带东端的一条多期活动的剪切带。结论秦岭—大别造山带经历了不同构造体制转换、板块构造系统发展、板块构造体系向陆内构造体系转换以及大陆动力学体系发展演化等地质过程;显示出古生代以来逆时针"转动挤压"到"三面围限"的动力学过程。Aim To study the tectonic deformation of several significant tectonic belts in the Qiuling-Dabie orogenic and discuss the process of dynamics. Methods Analyzing the conversion from plate tectonics system to intracontinental tectonic system and the evolution of continental dynamics system and other geological processes by studying the geometry and kinematics characteristics of these tectonic belts. Results （ 1 ） Luan chuan tectonic belt is intracontinental convergence belt of Erlangping back-arc basin and southern margin of the North China plate, which was formed at about 365 Ma. The orientation of major stress is 240→60°. （2）The Shangdan fault zone was formed at about 260 Ma. The orientation of major stress is 220→40°. The flattening deformation which is the chief in all deformations and positive flower structure shows the character of within plate collision zone. （3） Xiangguang fault belt is the convergence belt of Yangtze plate and Dabie orogenic belt, which was formed at about 220 Ma. It fomed oblique convergence between the Yangtze plate and the Dabie orogenic belt. The direction of plate convergence is 185°→5°（4） Yinma fault is a typical ductile shear zone with the nature of dextral translation . （5） Wuxue collision belt is a tectonic composite belt of the southern margin of the Dabie Mountains and the northern margin of Yan- gtze plate. It was formed at about 140 Ma caused by the Yangtze plate pressed Dabie Mountains from S → N. （6） YiLu tectonic belt is located in the north of the East Qinling orogenic belt. The main body is S →N direction imbricated thrust nappe structure. The rate of upper crustal shortening is to 52%. （7） Tan-Lu fault belt is a shear zone located at the eastern of Qinling-Dabie orogenic belt and has experienced multi-stage tectonic movements. Conclusion Qinling-Dabie orogenic belt has experienced transition of tectonic regime, systemic development of plate tectonics, the conversion from plate tectonics system to intracontinental tectonic system,

关 键 词：秦岭-大别造山带 商丹缝合带 大陆动力学 斜向汇聚 变形分解 

分 类 号：P541[天文地球—构造地质学]