Monitoring and Analysis of Surface Subsidence in Mining Area Based on SBAS-InSAR

DInSAR technique is easily influenced by decorrelation of time and space and atmosphere delay, SBAS(small baseline subset technique) was applied to process 13 scene of TerraSAR-X data. The residual DEM error, atmospheric delay error and orbit error are estimated and removed. The maximum subsidence rates of 2310 and 1301 working faces were 40 mm/a and 50 mm/a respectively by analyzing the subsidence rate of the coal mine area from 2012 to 2013. It found that the land subsidence of 2306, 2308, 2310 working faces is not obvious before November 15, 2012 by analyzing the timing cumulative subsidence map. Three candidate points of slowly decorrelation filter phase in the 2310 and the 1301 working faces were extracted respectively to be analyzed and we found that the relationship between sedimentation value and time was linear, moreover, the earlier the mining time was, the more the linear variation of the sedimentation characteristics was. Cumulative settlement values obtained by the SBAS and DInSAR were compared and analyzed and turned out that the difference between the two methods was less than 5 mm. The time sequence subsidences of several points in the trending and orientation of 2310 working face were selected and extracted, the surface subsidence of study area in different time period was quantitative analysis by analyzing the displacements of these points. Experiments show that SBAS-InSAR technology has a good application prospect in the monitoring and analysis of surface subsidence in mining area.