分析了GPS与INSAR数据融合的必要性与可行性,讨论了GPS与INSAR数据融合存在的主要问题,进一步探讨了利用GPS数据改善INSAR相位解缠算法,利用GPS与INSAR数据融合建立水汽模型和大气层延迟误差改正模型,以及GPS高时间分辨率和高平面位置精度与INSAR高空间分辨率和高高程变形精度有效统一的问题。

of the Tibet block relative to Golmud in the north and south directions is (9.3±4.6)mm/a, the strain velocity of the middle part in the west and east directions is (15.6±6.3)mm/a, reflecting the plateau lateral extruding movement. The Himalayan block is mainly compressing strain, and the middle part of the Tibet block is mainly extending strain. The highest extending and the compressing strain are 0.131×10−6/a and −0.189×10−6/a, respectively.

Global Positioning System (GPS) observations from three measurement campaigns from 1995 to 1999 are used in a study of the tectonic activity and earthquake hazards in North China. These GPS data were firstly processed together with about 13 Global IGS stations using the GAMIT software to get the baseline solutions, then crustal horizontal motion in ITRF97 frame and with respect to Eurasia were obtained based on these baseline solutions and their variance-covariance matrix using the GPS network adjustment software Power ADJ developed by Wuhan University. Using the GPS velocity field we estimate the annual accumulation of strain rate field and annual accumulation of density of strain energy field. These resulting fields show the following: (1) most stations move at a rate of (3-12mm/a)

We have determined approximate average rates of deformation in the Qinghai-Tibet plateau and its margins from the GPS data for last 10 years and the moment tensors from earthquakes between 1900 and 1999. We also determined the strain rate (seismic strain rate) associated with the seismic deformation using 254 Mw≥5.0 earthquakes, and estimated the shortening and extension rates for every block in the area as well. We also estimated the strain rate (geodetic strain rate) by 80 GPS sites' velocity vectors and analyzed characteristic of kinematics by two kinds of strain rates and discussed earthquake potential in the area. As a result, the deformation rates from seismic moment tensors and from GPS velocities are basically agreed with each other. It is feasi-ble to analyze seismic risk by comparing geodetic strain rate with seismic strain rate based on the opinion that strain energy will be released through earthquake. It is concluded that there is no strong earthquake potential (>M7) in the Qinghai Tibet plateau and its margins, but there is earthquake potential (>M5) in middle Tibet in a few years.

Wuhan Technical University Surveying and Mapping (WTUSM) carried out three GPS campaigns in the Tibetan Plateau since 1993. To improve the vertical component precision of GPS measurement, we estimated the remaining tropospheric refraction using the piecewise linear method after the SAASTAMOINEN model and corrected the tropospheric refraction by selecting one parameter for every two hours model to consider the variation of tropospheric refraction. Using the IGS combined ephemeris and corresponding EOP Series for 1995 and 1997 GPS campaigns, all baseline vectors were processed by GAMIT (Ver.9.71) software, and network adjustment was carried out in ITRF97 frame by PowerAdj software (Ver.3.3) which was developed by WTUSM considering the baseline vectors'full covariance matrix. The resulting vertical velocity field determined from GPS campaigns in 1995 and 1997 shows that the average uplift rate in ITRF 97 frame is about 7.8