Research On Deformation Monitoring Of Geological Hazards In Zhaotong,Yunnan Province Based On Sentinel-1A And L-SAR Satellites

The terrain and the geological structure of Zhaotong area in Yunnan province are extremely complex,and various geological disasters occur frequently,which seriously threaten the life and property safety of local residents and restrict the economic development of the area;The successful operation of the L band differential interferometric SAR satellite developed by China(L-SAR)marks that InSAR technology will be widely used in the investigation and research of geological disasters in China,providing technical support for disaster prevention,mitigation and avoidance in areas with high incidence of geological disasters.This article analyzes the application difficulties of InSAR technology in the Zhaotong area and proposes data selection and processing plans suitable for the research area;Based on the ascent and descent orbit data obtained from the Sentinel-1A satellite in a long time series,the IPTA InSAR technology is used to obtain the spatial distribution and temporal variation characteristics of the disaster body.Finally,based on the monitoring results obtained from Sentinel-1A data,the ability of the LSAR satellite to apply to the topographic mapping and deformation field acquisition in Zhaotong area is verified.The specific research results are as follows:(1)The InSAR technology suitable for deformation detection in areas with complex terrain and severe vegetation coverage has been systematically summarized.According to the imaging characteristics of SAR satellites in the study area,this thesis analyzes the applicability of ascend and descend orbit SAR data to deformation monitoring in Zhaotong,Yunnan,and analyzes the impact of interference coherence on the study area,and proposes the data processing scheme in this paper.(2)The application of InSAR technology in the Zhaotong area of Yunnan is greatly affected by atmospheric and terrain residuals,and conventional PS-InSAR technology cannot meet the number of effective monitoring points.This study conducts research on geological disaster deformation monitoring in the region based on interference point target analysis technology.By comparing the monitoring results obtained by Stacking InSAR technology,it is shown that IPTA technology can effectively suppress the impact of atmospheric errors and terrain errors.(3)In order to obtain the spatiotemporal characteristics of the distribution of landslide disasters in the study area,deformation information was extracted based on Sentinel-1A orbital data,and the spatial characteristics of disaster distribution in the study area were obtained by combining terrain information;Combining IPTA InSAR and MSBAS technologies,the deformation characteristics of typical landslide masses were analyzed.(4)Regarding the verification of the observation ability of L-SAR satellites in complex mountainous areas,this article takes the Zhaotong area as an example and compares the geocoded SAR data before and after calibration.It is concluded that geometric calibration has the ability to correct the positioning accuracy of L-SAR data in the Zhaotong area.By comparing similar DSM products,it is concluded that L-SAR satellites in the Zhaotong area have the ability to obtain higher spatial resolution terrain products.Finally,by comparing the monitoring results of Sentinel-1A data with L-SAR data,it was found that L-SAR data can achieve good monitoring results under long-term baseline conditions,proving that L-SAR satellites can monitor geological disasters in complex terrain conditions.