Monitoring Large Gradient Deformation by Means of Time-Series LuTan-1 Synthetic Aperture Radar Images

In order to provide a feasible technical strategy for large gradient subsidence monitoring, a time-series interferometric synthetic aperture radar (InSAR) technique combining high spatial and temporal resolution LuTan-1 SAR data was applied for subsidence monitoring. The capability of LuTan-1 images for large gradient subsidence monitoring was analyzed and discussed, and quantitative evaluation was implemented in combination with the field measurements. The accurate and recent digital elevation model generated by bistatic LuTan-1 data was used for terrain phase removal. The dynamic subsidence of Datong mining area was extracted based on the time-series InSAR techniques. In combination with the field leveling measurements and Sentinel-1 monitoring results, several conclusions were derived. Firstly, there are four main deformation areas in the monitoring area from Jan to May 2023, and the maximum cumulative deformation reach to −4.206 m. The dynamic spatial and temporal deformation details of mining areas were characterized, which also revealed the relationship between mining subsidence law and mining activities. Secondly, all of the subsidence details were extracted based on the LuTan-1 data, which indicated the capability of large gradient deformation monitoring. Thirdly, based on the field leveling measurements, the root mean square error of deformation monitoring results with LuTan-1 data is less than 40 mm, and the maximal relative error is less than 4%. The complete and accurate subsidence details of the mining area with large gradient deformation were obtained. The results indicated that LuTan-1 satellites provided an effective support for large gradient deformation monitoring, which is significant for mining subsidence law research, disaster monitoring, and management.