| Far field effect of collision between Indian plate and Euro-Asia plate since Cenozoic era reactivates some deep and huge faults around Qinghai-Tibet plateau and its margins, such as Alyth fault, Xianshuihe fault, Talas Fergana fault, et al. These faults control the geological evolution of margin area of Qinghai-Tibet plateau. Be important parts of plateau, Pamir-West Kunlun mountain and Yushu distribute around these faults. These area features with strong tectonic deformation, a sundry of structural styles, a lot of active tectonics and frequent earthquakes, having recorded the critical geological information in the process of Cenozoic plateau uplift. This dissertation heads to study on the late Cenozoic deformation of thrust-belt of West Kunlun mountain and do some analysis for coseismic deformation of 2010 Qinghai Yushu earthquake, looking forwars to exploring the uplift mechanism in northwestern plateau and the contribution of 2010 Yushu earthquake to plateau uplift.At first, based on the interpretation of satellite images, processing of DEM data, analysis of river terraces, interpretation of geophysical profiles, as well as field morphotectonic and geological investigations and observations, a qualitative and quantitative morphotectonic and deformed features of thrust-belt of West Kunlun moutain was investigated. Some cognition are got:Spatial geomorphology analyses find that a very abrupt landform zone distributed between Pamier-West Kunlun tectonic zone and Tarim Basin. Swath DEM profiles across this zone suggest huge vertical elevation change, indicating strong structural activity. Different mean elevation plane suggests the Pamir Plateau has an uplifting mechanism of thrusting with a right lateral component which is different from West Kunlun mountain's nearly pure thrusting. Main planation surfaces appear at 3600-5200 meters high. Slope analyses find that slope angle is rather abrupt and big roughness suggests a strong tectonic activity. Also slope analyses suggest that the slope angle is ca.15°in the basin and ca.33°in the inner plateau. Rivers tend to be offset by fault, making local drainage pattern become L-like. Tributaries tend to occurred on the east side of the river, suggesting east basin's warping. Hyposometric curve indicates study area is in the geomorphic infancy phase and the mountain is still uplifting.River geomorphic study finds that Keliya he terraces and Cele he terraces are tectonic terraces, which can arguably reflect mountain uplifting. Keliya he terraces research suggest Keliya he River has a Quaternary mean incision rate of 0.15mm/a, a mean incision rate of 0.76mm/a since 30.86ka,1.34mm/a since 12.44ka, these datum reflect an accelerated uplift past of West Kunlun mountain.Yingjisha anticline plunges east, this pheonomenoum only makes sense in the case of Yingjisha anticline's growth ont only controlled by main thrust fault in hinterland but also influenced by Aigusi anticline's lateral-propagation. Yingjisha growth anticline decided the drainage pattern, making river flow along its strike on the south flank of it. Field investigation, as well as analyses about DEM and geophysical profiles across Yingjisha anticline, finds Yingjisha anticline is a detachment anticline, identifying Q1 growth fold developed on the flank of anticline from geophysical profiles. Fit with excess area model we find Yingjisha anticline has a shortening magnitude of ca.722km and a mean shorten rate of ca.0.72mm/a since 1Ma.At the same time, this dissertation also focus on the coseismic deformation of Qinghai Yushu earthquake(Ms7.1) attacked on April 14,2010. Field investigation found that Qinghai Yushu Ms7.1 Earthquake produced a～65 km long co-seismic surface rupture zone which strikes 310°and dips NE. The entire zone is composed of two parts:the western section is about 19 km-long and the eastern section 30 km. Between these two sections, a 15 km-long zone surface rupture gap is observed. Surface ruptures display common sinistral lines mainly featuring right stepping en-echelon ruptures, while vertical offsets developed. The ratio between co-seismic vertical offset (dv) and horizontal offset (dh) ranges from 0.13 to 0.53, while the geomorphic dv/dh rate of 0.27～0.63 is close to co-seismic dv/dh (0.13～0.53), indicating that the Yushu NanShan uplift probably shows the same kinematic and dynamic characteristics. In other words, the Yushu Nan Shan uplift is resulting from the cumulative vertical offsets produced by many earthquakes similar to Yushu earthquake along Yushu fault in the geological history. We conclude that we need 1800-2600 earthquakes similar to Yushu earthquake to form Yushu Nan Shan. Former research reckon the recurrence period of the Yushu section of Ganzi-Yushu fault zone to be 120-200 years, which would then make us believe that this fault section's activity started 200-400 ka ago.
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