Abstract: By carefully interpreting the Xizang Landsat imageries, we have discovered a series of active faulting belts and recent basins. Moreover, magmatism and volcanic and geo thermal activities may come very intensive in Xizang. We have applied the Landsat image to making the seismo-tectonic map of Xizang. It shows that the Xizang plateau has three main structural types. The south Xizang area consists of many closely parallel and rectilinear lineaments which indicate an intensively compressive deformation; the middle Xizang area presents continually lenticular-like structures which show a plastic deformation; and the Qiangtang plateau possesses conjugated fracture deformation. These properties determine the seismic activities in the Xizang region and the three seismic areas can be classified.There have been more than 284 earthquakes with magnitude above 5 since 1870. We have subdivided the seismic events occuring during 20 th century into three periods, each extending about 30 years. Now the third period is going to come to an end.Finally we point out that earthquake frequency and intensity in Xizang are related to the collision of the India-Eurasia plate.

摘要： 陆地卫星影象表明西藏地区存在一系列活动断裂带,晚第三纪以来的新生盆地和火山活动都十分强烈。从卫星照片中的线性构造及其组合特征分析,西藏高原具有三种不同的构造组合,雅鲁藏布江以南多为近东西向线性构造,为强烈挤压的形变特征,中部多为连续分布的透镜状构造,反映了地壳物质塑性流动的形变特征,羌塘高原则为共轭破裂的形变特征。这些特征客观地反映了西藏高原各块体之间的力学性质和介质条件的差异,也控制了西藏地区的地震活动性。