Geological Factors for the Formation of Xi＇an Ground Fractures  

作　　者：Jianbing Peng Wei Qu Jun Ren Qin Zhang Feiyong Wang 

机构地区：[1]College of Geology Engineering and Geomatics, Chang'an University, Xi' an 710054, China [2]Key Laboratory of Western China' s Mineral Resources and Geological Engineering, Ministry of Education, Chang'an University, Xi' an 710054, China [3]Seismological Bureau of Shaanxi Province, Xi' an 710068, China

出　　处：《Journal of Earth Science》2018年第2期468-478,共11页地球科学学刊（英文版）

基　　金：supported by the National Key Basic Research Project of China (No. 2014CB744703);the National Natural Science Foundation of China (Nos. 41790445, 41731066, 41674001, 41202189, 41274004, 41274005);the Natural Science Basic Research Plan of Shaanxi Province, China (No. 2016JM4005);the Special Fund for Basic Scientific Research of Central Universities (Nos. CHD300102268204, CHD2014G1261050, CHD2014G3263014);the China Postdoctoral Science Foundation (No. 2013M530412)

摘　　要：Xi＇an ground fractures are the most typical ground fractures in China. Fourteen fractures have nearly divided the historical city into several distinct sections. These fractures are parallel and dis- tributed in NEE direction at the same interval, with all features exhibiting a down dropping southerly block which extends to connect with the underlying fault. The activities of fractures are primarily ex- pressed as normal faults. The faulted strata are well defined and dislocation displacement increases with depth. Thus, fractures have the characteristics of syn-sedimentary faults, which constitute the hanging wall of the Lintong-Chang＇an fault branch system. Crustal thinning caused by the uplifting of upper man- tle provides a power source for extension and stretching along the fracture surface of the upper crust, which results in a series of extensional faults and the suitable conditions for forming massive ground frac- tures. The movement of tectonic blocks influences the normal dip-slipping tension of Lintong-Chang＇an fault branches, and produces a series of secondary tectonic fractures adjacent to surface, which constitute the prototype of ground fractures. The recent regional tensile stress produced by modern mainland de- formation, also profoundly influences the current activity of Xi＇an ground fractures.Xi＇an ground fractures are the most typical ground fractures in China. Fourteen fractures have nearly divided the historical city into several distinct sections. These fractures are parallel and dis- tributed in NEE direction at the same interval, with all features exhibiting a down dropping southerly block which extends to connect with the underlying fault. The activities of fractures are primarily ex- pressed as normal faults. The faulted strata are well defined and dislocation displacement increases with depth. Thus, fractures have the characteristics of syn-sedimentary faults, which constitute the hanging wall of the Lintong-Chang＇an fault branch system. Crustal thinning caused by the uplifting of upper man- tle provides a power source for extension and stretching along the fracture surface of the upper crust, which results in a series of extensional faults and the suitable conditions for forming massive ground frac- tures. The movement of tectonic blocks influences the normal dip-slipping tension of Lintong-Chang＇an fault branches, and produces a series of secondary tectonic fractures adjacent to surface, which constitute the prototype of ground fractures. The recent regional tensile stress produced by modern mainland de- formation, also profoundly influences the current activity of Xi＇an ground fractures.

关 键 词：Xi＇an ground fracture tectonic property basin structure continental dynamics. 

分 类 号：P642[天文地球—工程地质学]