摘要
中国地壳运动观测网络基准网GPS连续观测 ,获得了 2 0 0 1年 11月 14日昆仑山 8.1级大地震前后中国大陆 ,特别是西部地区的地壳水平运动信息 .以东部长期相互间相对水平位移很小的几个站组成的一组稳定点作为基准 ,据此获得水平位移分量时间序列 .2 0 0 0年 11月上旬起中国西部的GPS基准站开始出现显著的异常位移 ,此后在云南及四川发生多次 6级左右的地震 .自 2 0 0 1年 4月中旬开始 ,中国西部GPS基准站向北的水平位移速率明显减小 ,甚至反向 ,临震前及震后略有恢复 ,但震后向北的水平位移速率仍减小 ,并有明显的向西运动 .近几年中国大陆西部 (相对东部 )的地壳运动过程表明 ,印度板块的向北挤压是昆仑山8.1级大地震的主要力源 ,大地震释放了大量的能量 ,印度板块对中国大陆的作用力明显降低 ,大震后至 2 0 0
The continuous GPS observation at the fiducial stations in the Crustal Movement Observation Network of China recorded the crustal movement of Chinese mainland before and after the great Kunlun Mountain earthquake of M =8.1 on November 14, 2001, especially the horizontal crustal movement in the western part of China. Based on the datum defined by a group of stable stations with small mutual horizontal displacements for a few years, the time series of horizontal displacements at fiducial stations were obtained. Significant anomalous horizontal displacements had appeared at the fiducial stations in the western part of China since early November 2000 and several earthquakes with magnitudes about 6.0 had occurred in Yunnan and Sichuan Provinces. The north components of the horizontal displacement at the fiducial stations in west China had decreased significantly even changed in opposite sense since mid April 2001. After the earthquake the northward displacements still decreased and there were significant westward displacements. The process of the crustal movement in the western part of Chinese mainland (in reference to east China) suggests that the main source of the force for this earthquake came from the northward pushing of the Indian plate. The great earthquake released a large amount of energy, the action applied by the Indian plate to Chinese mainland diminished significantly and after the great earthquake the seismic activity in Chinese mainland were significantly reduced until the end of 2002.
出处
《地震学报》
CSCD
北大核心
2003年第6期653-660,共8页
Acta Seismologica Sinica
基金
国家重点基础研究发展规划项目 ( 95 13 0 3 0 7)资助
关键词
中国
地壳运动
GPS
地震预报
时间序列
crustal movement
GPS
earthquake prediction
great Kunlun Mountain earthquake of M =8.1
time series
