Research on time series InSAR monitoring method for multiple types of surface deformation in mining area

Interferometric Synthetic Aperture Radar (InSAR) has become the primary remote sensing detection method for monitoring significant surface subsidence and deformation caused by underground coal mining. Time Series InSAR has been intensively researched in mining-caused deformation monitoring for its ability to provide surface deformation time series, with Small Baseline Subset InSAR (SBAS-InSAR) and Permanent Scatter InSAR (PS-InSAR) being two classical methods. To obtain the incline and curvature in mining areas and assess the building damage, this paper exploits the SBAS-InSAR and PS-InSAR techniques to estimate surface incline and curvature, following the principle of directional derivatives. The surface beneath the villages and the industrial square near the 7221 Grout-filled working face in the Huaibei mining area of Anhui Province, China, was analyzed. The estimated surface incline and curvature with SBAS-InSAR were within the threshold values specified for Class I damage, while PS-InSAR showed <1% of measurements that exceeded this threshold. This paper provides a method for monitoring the surface deformation beneath the buildings in the mine area. Meanwhile, the dynamic analysis of the damaged buildings provides a basis for determining the influence range with grout-filled working faces.