时序InSAR技术地表沉降监测结果可靠性及沉降梯度分析

为系统评价时序InSAR技术监测结果的精度和可靠性,进一步挖掘监测结果中隐藏的空间地理信息,利用两种时序InSAR技术对天津市及周边区域地表沉降情况进行监测,并基于水准数据测量结果、不同时序InSAR技术监测结果以及夜间灯光数据二次分析结果,研究了系统评价监测结果可靠性的方法,对监测结果进行了精度和可靠性的评价。在此基础上,基于ArcGIS空间插值与梯度分析方法,对研究区两个重点沉降区域进行了沉降梯度分析。研究结果表明:1研究区时序InSAR技术监测结果精度较高、可靠性较好;2重点沉降区域分布于天津市市区周边辖区,而市区相对比较稳定;3沉降梯度较大区域多分布于"沉降漏斗"的边缘,沉降梯度大小与沉降速率之间没有直接联系。

Analysis of the Reliability and Subsidence Gradient for theSubsidence Monitoring Result of Time-series InSAR

In order to systematic evaluate the precision and reliability of the monitoring result of time-series InSAR and further exploit the geographic information hidden in the monitoring result,two different time-series InSAR have been carried out to monitor the Tianjin city and its surrounding ground subsidence.Based on the leveling data,the monitoring results of different time-serise InSAR and the night light data,a systematic algorithm has been proposed to evaluate the precision and reliability of the InSAR’s results.Also the ArcGIS interpolation and gradient calculating method has been used to analyse two seriously subsidence regions’ gradient of the study area.The results show that:①Monitoring precision and reliability of the time-series InSAR is very good;②Most of the seriously subsidence regions locates in the surrounding areas of the Tianjin city,while the Tianjin city has not subsided nearly.③Large subsidence gradient mostly distributed in the edge of the “sinking funnel”,there is no direct link between the subsidence rate and gradient.