2004年苏门答腊地震前后海面高趋势的变化

The Variation of Sea Surface Height Trends Before and After 2004 Sumatra Earthquake

利用苏门答腊附近海域T/P、Jason-1测高卫星近20年的海面高连续观测资料,分别计算了该区域(80°E^105°E,5°S^20°N)在2004年苏门答腊大地震前后的海面高变化趋势,并与该区域对应时间段GRACE重力卫星反演的地表质量迁移结果进行比较。研究结果表明,由卫星测高观测资料估算的震区地震前后海平面趋势的变化与卫星重力反演结果基本一致。由于卫星测高沿轨观测具有高精度、高时空分辨率的特性,卫星测高资料估算的海平面趋势变化可以更为准确地反映震区海平面变化的局部特征。还对该区域震后形变特征进行了初步分析。

Monitoring post-seismic deformation is an important research both in geodesy and seismology. In this paper, nearly two decades of T/P and Jason-1 continuous altimeter data is used to calculate the trends of sea surface height （SSH） changes before and after the Sumatra earthquake in the areas of 80°E-105°E ,5°S-20°N. We compare the variation of SSH trends with the result of the surface mass migration from GRACE, and find that the variation and the result retrieved from GRACE basically are the same. Due to the fact that the altimeter data has the highly accuracy and temporal-spatial resolution along the track, the variation of the SSH trends calculated from the altimeter data can more accurately reflect the local characters of the SSH changes in the Sumatra earthquake areas. This paper preliminary analyses the local post-seismic deformation characters.