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Jiawei Pan, Key Laboratory for Continental Dynamics of MLR, Institute of Geology, Chinese Academy of Geological Sciences (China)
Haibing Li, Key Laboratory for Continental Dynamics of MLR, Institute of Geology, Chinese Academy of Geological Sciences (China)
Van Der Woerd Jerome, Institut de Physique du Globe de Strasbourg EOST (France)
Zhiming Sun, Key Laboratory of Crust Deformation and Processes, Institute of Geomechanics, Chinese Academy of Geological Sciences (China)
Junling Pei, Key Laboratory of Crust Deformation and Processes, Institute of Geomechanics, Chinese Academy of Geological Sciences (China)
Jialiang Si, Key Laboratory for Continental Dynamics of MLR, Institute of Geology, Chinese Academy of Geological Sciences (China)
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The thrust belt of West Kunlun Mountain front ranges in an approximately E-W direction from Aqik anticline to Pamir syntaxis for about 600km. It is an important tectonic belt between Tarim Basin and the northwest part of Qinghai-Tibet Plateau and also a main part of the foreland Basin of West Kunlun Mountain.
Based on the interpretation of Landsat ETM satellite images, processing of DEM data, analysis of topographic maps and construction of profiles, combined with field morphotectonic investigations and observations, the authors conducted quantitative and semi-quantitative studies of the morphotectonic features of the thrust belt. A possible tectonic pattern of the thrust belt and the uplift rate of the West Kunlun Mountain were also discussed in this paper. Typical morphotectonic features developed along the thrust belt were systematic curving of streams, changing of alluvial fans, asymmetric anticlines, large scale normal faults and asymmetric terraces.
The main conclusions are as follows:
1. The thrust belt was segmented into two parts by Sangzhu River. Guman anticline was developed in the west part with a tectonic pattern of north vergent thrust accompanied by south vergent back thrust, whereas a number of asymmetric anticlines were developed in the east part indicating the north vergent thrust but without visible back thrust features on the ground.
2. Rivers in the front of West Kunlun Mountain recorded two times rapid uplift in Later Cenozoic on longitudinal valley profiles. This two times uplift were related to the activity of West Kunlun North Fault and Tiekelike Fault.
3. The north vergent thrusting of the thrust belt caused doming on the ground and made the formation of Guman anticline. During the formation of Guman anticline, it propagated from west to east, causing systematic curving of streams and ultimately the formation of asymmetric terraces.
4. Uplift rates of the West Kunlun Mountain have been estimated based on deformed height of Guman anticline and river terraces: the minimum uplift rates were 0.21-0.25mm/yr from the Late Pliocene-Early Pleistocene and 1.5mm/yr since 100ka BP.
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