Study On The Method Of Monitoring Deformation In Coal Mining Area Based On Interferometric Synthetic Aperture Radar

Fushun city was prosperous for its coal mining.Due to the long-term and large area underground coal mining,the problem of the surface deformation in Fushun City has gradually emerged and intensified.Therefore,it is necessary to conduct the long-term,efficient and accurate surface deformation monitoring in Fushun City.Small baseline set(SBAS-InSAR)that integrates the images to several small baseline datasets,is a kind of a coherent target multiple baseline D-InSAR processing method,which can reduce time decorrelation of the interference and improve the spatial resolution,and can be used for monitoring the surface deformation in long time.Based on SBAS-InSAR technology,11 ALOS-PALSAR images acquired during 2007 and 2011 and 8 COSMO-SKYMED images acquired between 2011 and 2013 have been used to monitor and analyze the surface deformation of Fushun City caused by coal mining.The Fushun deformation monitoring system has been designed,and InSAR monitoring results were verified by the leveling and GPS monitoring data.The main contents are as follows:1)The Application design of Fushun deformation monitoring method based on InSAR technology.For project requirements,the DEM,leveling and GPS monitoring data have been collected to verify the monitoring results of InSAR;All SAR data in the monitoring area have been investigated,and some SAR data has been selected for use;Firstly,the settlement and deformation rates of high precision coherent target points have been obtained by using SBAS-InSAR method;According to the coordinate conversion,SBAS-InSAR results have been analyzed geographically;Then,the Kriging method have been used for the interpolation of high density coherent target points;Moreover,combined with field exploration,the figures of deformation rate and cumulative deformation of subsidence area have been plotted,the center position of the deformation funnel have been determined;Finally,the affected area boundary of mining subsidence have been delineated.2)The verification of accuracy of monitoring data by InSAR technology.In this paper the analysis is focused on the old subsidence,no corner reflector can be used for the verification,and so,leveling and GPS subsidence monitoring data have been captured for verifying the accuracy of InSAR monitoring data;Additionally,robust correlation method and the error method have been proposed to evaluate InSAR processing results;because the comparison points in two monitoring methods are different,the most appropriate points based on the consideration of the terrain and other factors have been selected to complete the accuracy verification;The verification shows that the results of InSAR technology are highly correlated with the results of traditional monitoring method,and the accuracy of the data is also consistent with the technical design requirements;Furthermore,In the precondition of absence of corner reflector,two methods have been proposed to validate InSAR processing results,it is shown that the SBAS-InSAR technique can be used to monitor surface subsidence deformation with high precision in large urban area,which improves the efficiency of long-term high precision surface subsidence monitoring in large area,and reflects the surface subsidence more comprehensively and reliably.At the same time,the historical surface deformation monitoring has been realized by utilizing the InSAR technology,which breaks the limitation of the traditional monitoring method,and indicates the superiority of the technology used in the surface deformation monitoring in the mining area.