Structural style and tectonic significance of foreland beltin the middle segment of northern Yangtze plate
Wang Kai1,2, Liu Shaofeng2, Wang Ping3, Jiang Chengxin2, Gao Tangjun4
1. Xi'an Institute of Geology and Mineral Resources, Xi'an 710054;
2. State Key Laboratory of Geological Processes and Mineral Resources, College of Geosciences and Resources, Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, China University of Geosciences, Beijing 100083;
3. School of Geography, Nanjing Normal University, Nanjing 210000;
4. Research Institute of Exploration, Southern Exploration Company, SINOPEC, Chengdu 610041
The foreland fold-and-thrust belt developed in the middle segment of northern Yangtze plate underwent many periods of structural superpose and reformation,whose complex structural deformation distinctly records the process of collision and subduction between the Yangtze plate and Qingling-Dabie micro-plate in Mesozoic and the later tectonic evolution after transforming into intracontinental deformation.Based on the analysis of the structural deformation styles and kinematic characteristics in the middle segment of northern Yangtze plate,Baokan-Fangxian area,this paper assures the specific location of the front of the foreland fold-and-thrust belt in the northern Yangtze plate and the features of the thrust and napping tectonics,which developed at the later stage,and also identifies a sinistral strike slip fault running through the region of Baokang,Fangxian and Puxi.At the same time,the analysis shows that the strike slip fault played a regulating role in the process of Yangtze plate clockwise rotation relatively to the north China plate after the period of Middle-Jurassic,which is vital to understand the tectonic evolution of the northern Yangtze plate in Mesozoic.