：鲜水河断裂现今走滑速率约10mm/yr，是青藏高原最活跃的断裂带之一。虽然在其北侧和西部先后发生了汶川、玉树地震，然而在该断裂带上近四十年未有7级以上强震，因此其地震危险性备受关注。本项目利用近20年积累的InSAR/GPS资料研究鲜水河断裂震间形变时空分布特征，并基于此讨论其孕震规律和地震危险性。内容包括：1）研制高精度InSAR时间序列分析方法；2）联合InSAR/CGPS建立鲜水河断裂震间形变时间序列；3）反演该断裂震间滑动速率的时空分布，并结合历史地震、地质长期滑动速率探讨断裂各段的地震危险性；4）研究汶川、玉树地震对鲜水河断裂的影响；5）联合GPS/InSAR平均速率建立该断裂带高分辨率的速度场；6）联合CGPS/InSAR时间序列建立时间序列速度场。本项目有助于进一步认识鲜水河断裂现今构造活动性和青藏高原的形变机制，同时为该断裂现今发生强震的可能性提供关键的基础数据。

The Xianshuihe Fault (XSHF) is one of the most active faults at the eastern boundary of the Tibetan plateau with a strike-slip rate of about 10 mm/yr. Large earthquakes (M>7) are absent along the XSHF in about 40 years although two large earthquakes, Wenchuan and Yushu, occurred at its northern and western side respectively. It implies very high probability of large earthquake, which has got substantial attentions over many years. In this proposal, we study the spatio-temporal interseismic deformation and the earthquake hazard on the XSHF using geodetic data from InSAR and GPS collected in the past two decades. The proposal includes six main tasks: 1) Develop an advanced time series analysis algorithm with an accuracy of a few millimeters per year; 2) Make an interseismic deformation time series of the XSHF using InSAR/GPS data; 3) Invert the spatio-temporal distribution of slip rate on the XSHF, and estimate the earthquake potential based on historical earthquakes, long-term geological fault slip rate and the present-day interseismic deformation model; 4) Study stress changes and earthquake hazards along the XSHF associated with the Wenchuan and Yushu earthquakes; 5) Determine a high resolution velocity field covering the XSHF using InSAR rate map and GPS velocities; 6) Determine a time sereis velocity field using CGPS velocities and InSAR rate map time series. Our proposed study will provide important data and explanations for earthquake hazards assessment of the XSHF and the mechanism of the present-day deformation of Tibet.