Investigation of mining subsidence over three major coal mines using time-series SAR interferometry

Coal mining will lead to geological disasters such as surface subsidence and ground fissures, especially the goaf after mining. Therefore, it is particularly important to monitor the deformation of the coal mining area. In this study, we used the small baseline subset InSAR technology to measure the deformation of three major coal mining areas near Hunchun city to detect the spatiotemporal distribution of surface deformation in two periods from 2018 to 2021. In addition, by combining interferograms from multiple monitoring periods, several historical high-deformation areas were mapped. The research shows that from 2018 to 2021, significant mining-induced subsidence occurred in the southern and northeastern parts of the Baliancheng Coal Mine and the eastern part of the Yingan Coal Mine. The eastern part of the Yingan Coal Mine experienced the maximum cumulative LOS deformation, reaching up to -348mm. Additionally, railways and highways pass through the severe subsidence areas in the central part of the Yingan Coal Mine and the northeastern part of the Baliancheng Coal Mine, respectively, which will adversely affect their safe operation.