基于SBAS-InSAR和PS-InSAR技术的西安市地表形变监测与分析OA

Xi'an City currently faces concentrated geological disasters such as ground subsidence and fissures.To address these issues,this paper used Sentinel-1A radar image data from June 2015 to March 2024 and utilized small baseline subset interferometric synthetic aperture radar(SBAS-InSAR)technology to obtain the long-term surface deformation evolution characteristics in the main urban area of Xi'an City over nearly nine years.Meanwhile,for the Yuhuazhai and Qingliangshan-Fengqiyuan areas within the main urban area,the SBAS-InSAR and permanent scatterer synthetic aperture radar(PS-InSAR)technologies were respectively applied to obtain the surface deformation characteristics in 2019,and the monitoring results of the two technologies were cross-validated.On this basis,the profile time series analysis was carried out for the two areas.The results show that the main urban area of Xi'an City as a whole presents a significant subsidence trend from 2015 to 2018.From 2018 to 2024,the core area of the main urban area extending northeastward to southwest shows a large-scale surface uplift phenomenon.Among the typical deformation areas,the Yuhuazhai area shows a significant rebound feature after continuous subsidence,while the Dianzicheng area presents an overall uplift trend with a gradually decelerating rate.The Qingliangshan-Fengqiyuan and Matengkong areas both exhibit a continuous subsidence trend.The monitoring results of the two InSAR technologies for the Yuhuazhai and Qingliangshan-Fengqiyuan areas are basically consis-tent,indicating that both are reliable in urban surface deformation monitoring.The profile analysis results show that during the monitoring period,both areas form main and secondary subsidence centers:The subsidence rate in the Yuhuazhai area changes sharply from large to small,while the subsidence rate in the Qingliangshan-Fengqiyuan area is relatively uniform and gradually decreases.