基于Doris的台湾集集地震同震位移场计算

DETERMINATION OF COSEISMIC DISPLACEMENT FIELD OF TAIWAN CHI-CHI EARTHQUAKE BASED ON DORIS

基于公共开源软件Doris,利用三轨差分的DInSAR方法获取了1999年9月21日台湾集集地震的同震位移场。在数据处理过程中采用了一种有效的辅助解缠方法,较好地解决了利用统计费用网络流算法解缠时低相干系数像素的误差传播问题,使解缠精度得到一定改善,解缠速度显著提高。系统分析了干涉图中包含的误差,并利用GPS观测数据对轨道误差进行了改正。最终得到的斜距方向的同震位移场与GPS数据有很好的一致性。

The coseismic displacement field of the Chi-Chi ML7.6 earthquake in Taiwan island on 21 September, 1999 is determined with 3-pass DInSAR method using Doris software. An effective fix is applied to the unwrapping step which improved the SNAPHU（Statistical-Cost, Network-Flow Algorithm for Phase Unwrapping） result and reduced the unwrapping time greatly. The errors in the interferogram are analyzed and the orbit error is corrected by use of GPS observations. After the correction, the displacements in the slant range direction are well consistent with the GPS data.