Experimental Research On Radar Remote Sensing Monitoring of Coal Mining Subsidence in Loess Mining Area

摘要

The Loess covered areas include Shanxi, Shaanxi, Ningxia, Gansu and other provinces and is the main coal production base. The Loess Plateau is characterized by varied topography, complicated geological and geomorphic conditions and large thickness of mining coal seam, which results in many types of geological hazards, wide distribution and great threat. Therefore, it is very necessary to monitor the surface deformation by full coverage and all-weather monitoring. The vertical deformation information with high accuracy can be obtained by using D-InSAR technology. Compared with the traditional monitoring method, it has the advantages of high resolution, high coverage, all-weather measurement and low cost. With the continuous development of this technology, the surface subsidence monitoring technology of D-InSAR is gradually introduced to the ground subsidence monitoring of the coal mine area. However, due to the complex and varied landform in loess area, the monitoring difficulty of D-InSAR technology has increased a lot. It also makes the monitoring of conventional methods more difficult. Sentinel-1 satellite has been applied in October 2014. Sentinel data become a data source of SAR image. Sentinel data also become data support of D-InSAR technology, and can effectively monitor deformation. In this paper, the processing steps of D-InSAR technology and the problems existing in each step are briefly described and the technical flow chart is drawn. 4 consecutive pairs of interference pairs in the time of the bingchang mining area were treated with D-InSAR, and the mining area deformation maps of 4 continuous periods were obtained. Through the superposition of 4 deformation maps one by one, the gradual process of the mining area and the settlement of the mining area is obtained and analyzed. The measured subsidence data and the processed subsidence data are compared and analyzed, and the cross section map of the working face line and the longitudinal line is drawn. The results show that: Sentinel-1 satellite data can perform differential interference processing well and carry out large area continuous monitoring, and also can well reflect the subsidence trend of mining area, and suitable for small deformation monitoring in mining area. However, the vegetation has a greater impact on the D-InSAR processing results of the sentinel-1 satellite data. The higher the vegetation coverage, the worse the coherence of the interference pairs.