Ground Subsidence Monitoring In Handan Mining Area Based On InSAR Technology

Handan mining area is rich in mineral resources.Due to its high-intensity mining all the year round,the ground deformation is very serious,causing geological disasters such as ground fissures,ground subsidence and land subsidence.Therefore,comprehensive and real-time understanding of the surface deformation of the mining area is of great significance to ensure the sustainable development of the area.Synthetic Aperture Radar Differential Interferometry(D-InSAR)has a short monitoring period with low cost,and can quickly grasp the overall deformation of the surface of the subsidence area.Small baseline set radar interferometry(SBAS-InSAR)technology combines time-series SAR images into a set of short-baseline SAR images,increasing the sampling rate of data,effectively reducing the effects of time-loss and atmospheric phase.Especially in large-scale deformation regions,more accurate results can be obtained.Based on D-InSAR technology and SBAS-InSAR technology,this paper uses Sentinel-1A SAR data as data source to monitor the ground deformation of the Handan mining area.The main research work and achievements are as follows:(1)From October 2015 to March 2016,a total of five Sentinel-1A data were used to monitor the D-InSAR settlement in the Handan mining area,and the spatial distribution map of the surface deformation of the test area was obtained.The results show that twelve settlement funnels have been formed in the Handan mining area.These funnels are located in Yunjialing Coal Mine,Wannian Mine,Nanxinzhuang Mine,Jiaoyao Coal Mine,Hengjian Coal Mine,Dashu Village Mine,Xuecun Mine,Xiaoyan Mine.,Niuerzhuang Mine,Yangqu River Mine,Jiulong Mine,and Minmetals,the average settlement rate of each mine center is 30 mm/month.(2)Using the Sentinel-1A data from June 2015 to May 2016,the SBAS-InSAR settlement monitoring was carried out on the Handan mining area,and the annual average rate of land subsidence in the Handan mining area and the various period variables were inversely performed.The results show that a settlement funnel is formed in the mining area that is consistent with the geographical position of the D-InSAR.The average settlement of the central area of each settlement funnel in the test area is 215 mm,and the maximum settlement rate reaches 360 mm/yr.(3)Comparing the SBAS-InSAR monitoring results with the local leveling results of the study area.The authour found that the SBAS-InSAR monitoring results are basically consistent with the surface deformation trends of the level monitoring results.However,there are errors in the deformation size of the two,and the error between the two is small at the edge of the mining area with small deformation.The difference between the two is large in the center of the mining area with large deformation.The maximum error is 26mm,the average error is 9.4mm,and the medium error is 10.5mm.