Land subsidence monitoring in Yungang mining area in Datong City based on InSAR technology

Datong is rich in coal resources, but the development of mining area is restricted to a certain extent by geological environment problems such as land subsidence caused by coal mining activities. In order to monitor the land subsidence characteristics of Yungang mining area in Datong City, based on Sentinel-1A satellite data, this paper used Differential Interferometric Synthetic Aperture Radar(D-InSAR) technology to process the landscape images captured from June to July, 2020, and preliminarily obtained the characteristics of the subsidence area in the mining area, and the maximum subsidence amount in the monitoring area reached 4.6 cm/36 d. A Small Baseline Subset InSAR (SBAS-InSAR) is used to process 24 images photographed from January 2019 to December 2020, obtaining a long time series deformation of some subsidence areas in the monitoring area. The spatial distribution of this monitoring deformation is consistent with that of the deformation monitored by Persistent Scattered Interferometric Synthetic Aperture Radar(PS-InSAR) using 25 SAR images during the period from January 2020 to September 2020, both of which have coincident deformation trend. According to the above three InSAR monitoring results, there are as many as 12 obviously rapid subsidence zones evenly distributed in the mining area, among which the maximum subsidence rate is 180 mm/y, and the maximum cumulative subsidence in 2019—2020 is 333 mm, while there is no obvious deformation sign in the southeastern urban area. It provides scientific basis for monitoring and rational exploitation of ground subsidence in mining area.