基于SBAS-InSAR技术和Sentinel-1A的城市地表沉降监测

Urban Surface Subsidence Monitoring Based on SBAS-InSAR and Sentinel-1A

基于SBAS-InSAR技术对覆盖研究区2017—2018年20景Sentinel-1A影像数据进行处理,得到研究区年沉降速率及时序形变信息,并与PS-InSAR结果进行对比验证,最后进一步分析了研究区沉降的成因。结果表明沉降主要发生在燕郊镇中部与西部区域,平均沉降速率超过20 mm/a,集中沉降区域平均沉降速率超过36 mm/a,最大累计沉降达到74 mm。通过对比SBAS和PS监测结果表明,2种时序分析方法在大范围、持续缓慢城市地表形变监测中可以获取一致的地表形变运动趋势,但SBAS在监测地表形变细节更加有优势,在数据量有限的情况下,SBAS-InSAR技术监测的形变结果更可靠。研究区沉降主要与北京地区的城市化向东扩张及地下水开采有关。

Based on the SBAS-InSAR technology,20 Sentinel-1A images covering the study area from 2017 to 2018 were processed to obtain the annual subsidence rate and time sequence deformation information of the study area,and compare with the PS-InSAR results.The subsidence causes in the study area were further analyzed.The results show that the settlement mainly occurred in the central and western areas of Yanjiao Town.The average settlement rate was more than 20 mm/a,the average settlement rate of concentrated settlement area was more than 36 mm/a,and the maximum cumulative settlement was 74 mm.The SBAS and PS monitoring result comparison shows that the two time series analysis methods can obtain the same ground deformation movement trend in large-scale,continuous and slow urban surface deformation monitoring,but SBAS has more advantages in monitoring surface deformation details.The deformation results monitored by SBAS-InSAR technology are more reliable when the amount of data is limited.The study area settlement is mainly related to the eastward urbanization expansion and groundwater exploitation in Beijing.