利用Sentinel-1A数据、D-InSAR和沿轨干涉技术获取2016年高雄M_S6.7地震三维形变场

3D Displacement Field of 2016 Kaohsiung Ms6.7 Earthquake from D-InSAR and Along-Track Interferometry with Ascending and Descending Sentinel-1A Images

提出一种沿轨干涉技术来获取Sentinel-1A数据中burst重叠区域内的方位向形变,进而通过内插方法得到非重叠区的方位向形变。针对D-InSAR的雷达视线向形变与沿轨干涉的方位向形变精度差异,采用基于加权最小二乘的方法解算了2016年高雄MS6.7地震的三维形变场。结果表明,高雄地震的同震形变以垂直和东西方向形变为主,且形变主要分布在断层左右两瓣。左瓣抬升,最大达到12cm;右瓣下沉,最大达到8cm;左右两瓣均伴随着向西的位移,最大达6cm。在左右两瓣之间,该地震还具有西北-东南走向的断层特性。

Along-track interferometry＇method is proposed to obtain along-track displacements frombackward and forward interferograms within regions of burst overlap. The azimuth direction displace-ment component of non-overlap area is measured by interpolation. The experimental results show thatthe coseismic displacement of the Kaohsiung earthquake is predominantly vertical and east-west direc-tion, and mainly distributes in left and right valves of a blind fault. The left valve uplifts with a maxi-mum vertical displacement of 12 cm, and the right valve drops with a maximum vertical displacementof 8 cm. Meanwhile, they have a displacement westward, to a maximum of up to 6 cm. In addition,the Kaohsiung earthquake has a characteristic of northwest-southeast trend blind fault between theleft and right valve.