Surface Deformation Monitoring Of Changchun City Based On Time-Series InSAR Technology

Changchun is rich in land cover types.With the economic growth,the construction land in Changchun is increasing.The increase of construction land in Changchun,the history of coal mining in some areas and other human activities caused a large area of surface subsidence,which threatened the social and economic development and people's safety.Therefore,it is of great significance to carry out large-scale land subsidence monitoring in Changchun,divide the main areas of land deformation in Changchun,monitor the scattered points in the urban area,determine the deformation level and deformation range,and explore the correlation between the deformation and natural factors in Changchun.The traditional leveling monitoring method has high precision,but it is difficult to realize deformation monitoring in a large range due to its high cost and time consuming.In this paper,the Sentinel-1 data covering the Changchun area with orbital number 105 from the beginning of March 2016 to the end of October 2020 are used.SBAS-InSAR technology was used to study the surface deformation in a large area of Changchun,and PS-InSAR technology was used to monitor the urban area.The accuracy was verified by cross validation and external leveling data,and the characteristics of surface deformation in Changchun were analyzed.This paper obtains the following results:(1)To verify the reliability and applicability of temporal InSAR technology.The reliability and applicability of different time series InSAR technology are studied according to the monitoring results of different time series InSAR Technology Based on the same source data.The SBAS-InSAR monitoring results are compared with the PS-InSAR monitoring results,and the SBAS-InSAR technology has good internal coincidence accuracy in a large area;then the SBAS-SAR monitoring results and the PS-InSAR monitoring results are verified with the leveling results respectively,and the results show that the two methods have millimeter level monitoring accuracy,but the PS-InSAR technology has higher accuracy and is more suitable for the application in the high coherence area High urban monitoring.(2)To explore the spatio-temporal characteristics of surface deformation in Changchun City.Based on SBAS-InSAR for Changchun city surface deformation as a result,through the results of deformation rate and Changchun city administrative divisions,Changchun city land cover data and seismotectonic map overlay,analyzed the deformation characteristics of administrative region,the different land cover types,and Changchun city spatial characteristics change trend and seismic tectonic deformation has certain correlation;Space to Changchun surface deformation with different characteristics,based on the SBAS-InSAR of Changchun city accumulated deformation results,further analysis of each administrative region and in different types of soil cover area change trend of surface deformation on the time series,and the D-InSAR technique for a short period of time monitoring of Changchun city,verify the correlation between deformation and seasonal change.In this paper,SBAS-InSAR technology and PS-InSAR technology are combined,and different research methods are used for comparison.The ground deformation in Changchun is analyzed qualitatively and quantitatively,and the ground deformation field is obtained.The ground deformation results are basically consistent with the deformation,through the comparison with natural data,the ground deformation in Changchun is obtained The spatial distribution characteristics and regional evolution law of surface deformation provide a certain reference value for the prevention and control of land subsidence and future urban planning in Changchun.