昆仑8.1级地震前青藏块体东北缘构造运动特征

利用青藏块体东北缘1993、1999和2001年的GPS观测资料和1980年以来的跨断层流动形变资料，分析了昆仑8．1级地震前青藏块体东北缘地区水平运动演变与断层异常活动的一些特征。结果显示：震前水平运动与变形强度减弱，断层形变异常发育。结合块体和构造研究认为，青藏块体内部8．1级大震的蕴育和发生，对块体边界构造区域影响显著；震后调整和应力转移可能加速块体东北部某些构造部位应变能的积累。

FEATURES OF HORIZONTAL MOVEMENT IN NORTHEASTERN MARGIN OF QINGHAI-TIBET BLOCK BEFORE Ms8.1 KUNLUN EARTHQUAKE

By analying observational data of crustal deformation which include results observed by GPS in 1993,1999 and 2001, together with results of mobile deformation measurment crossing main faults since 1980, the features of regional horizontal movement and deformation evolution and abnormal fault activity in northeast margin of Qinghai Tibet block before the Kunlun \%M\%s8.1 earthquake are preliminarily studied. The results show that the regional horizontal movement and deformation intensity decreased before the earthquake, and anomalies of fault deformation developed. In addition, combined with the investigation on block and structure,the analysis indicates that the occurrence and development of this \%M\%s8.1 earthquake inside Qinghai Tibet block has obviously affected the tectonic region of block boundary, and after the Kunlun \%M\%s8.1 earthquake, the adjustment and shift of tectonic stress have probably promoted accelerating and accumulation of strain of some tectonic positions in this area.