河西走廊西段花海断裂几何学、运动学及区域构造意义

花海断裂位于河西走廊西段花海盆地内,总体走向NNW-SSE,长约38 km,为一条隐伏断裂,研究其空间展布、运动性质和活动历史对于理解青藏高原北缘的构造变形和扩展方式有重要意义.基于卫片解译、野外实地和槽探,结合光释光测年和地球物理资料,发现沿双泉子、大泉至小泉一带,发育一段长约8 km的地形陡坎,代表断裂控制下褶皱作...

Geometry,Kinematics and Regional Tectonic Significance of the Huahai Fault in the Western Hexi Corridor,NW China

The NNW-SSE striking Huahai fault develops in the Huahai Basin in the western Hexi corridor. Its spatial distribution, kinematics and activity are significance for understanding the tectonic deformation and outgrowth of the northern margin of the Qinghai-Tibet Plateau. Based on the interpretation of satellite images, field surveying, trenching, optical luminescence dating and existing geophysical data, the characteristics of Huahai fault are reported. A landform scarp develops along the Huahai fault, which is approximate 8 km long from Shuangquanzi, Daquan to Xiaoquan. This scarp is caused by the fault related folding. The fault extends southward to the northern Kuantanshan and Heishan ranges indicated by scarps, springs and landforms. The Huahai fault was once a normal fault in the Early Cretaceous, and was inversed to be a thrust fault in the Late Cretaceous. During the Cenozoic, the northward growth of the Qinghai-Tibetan Plateau resulted in development of a series of sinistrally transpressive faults such as the Sanweishan, Ganxiashan, Kuantanshan and Taerwan-Dengdengshan-Chijiaoziwo faults. These faults are boundaries of blocks between the Sanweishan and Altyn Tagh faults, and cause the uplift of the mountain ranges along faults, and the northeastward movement of blocks among faults. The thrusting of the Huahai fault is the response of this recent tectonic event.