基于InSAR的花莲形变监测分析OA

This study focuses on the vertical surface deformation before and after the MS7.3 Hualien earthquake on April 3,2024.Based on a total of 20 Sentinel-1A SAR images covering the pre-and post-earthquake events,the paper obtained the long-time series vertical deformation field of Hualien and its surrounding areas using PS-InSAR technology.By integrating the geological and tectonic background of eastern Taiwan,the paper analyzed the defor-mation characteristics of different geomorphic and tectonic units.The results indicate that time-series InSAR tech-nology can effectively overcome meteorological and geographical constraints and achieve large-scale,long-term monitoring of surface changes in earthquake-prone areas.Among these areas,urban regions have better monitoring results than forested areas due to higher interferometric coherence.Areas underlain by fluvial sedimentary deposits(such as Hualien County and the lower reaches of streams)exhibit significant post-seismic effects,whereas no clear post-earthquake surface change signals were found in forest-covered geological zones.The area with obvious surface changes caused by this earthquake is shaped like a regular ellipse,extending nearly in the NE-SW direc-tion.The long axis is consistent with the strike of the Hualien-Taitung Longitudinal Valley Fault Zone,and the de-formation intensity caused by the earthquake decreases from the coast toward the inland.