Abstract: The geological environment of Ordos platform is fragile, and geological disasters such as landslide, collapse and debris flow occur frequently, which pose a serious threat to people's production and life and economic construction. Based on 76 Sentinel-1 images of a local area of the Ordos platform from January 2021 to August 2022, combined with SBAS-InSAR and CR-InSAR technologies, this study analyzes the abnormal surface deformation trends in the study area through time series deformation information and verifies the accuracy. By integrating the interpretation of geological hazard points from GF-2 satellite remote sensing images and conducting field validations, a comprehensive analysis is performed on two identified typical hazard points. The results show that this technology can achieve millimeter-level accuracy in surface deformation. According to the 《Geological Disaster InSAR Monitoring Technology Guide》(T/CAGHP 013—2018), the accuracy has been upgraded from Level II to Level I. During the monitoring period, 83% of the study area's deformation rate was within -20 to 20 mm/a, indicating a stable state, while the remaining 17% had potential hazards. A total of 41 geological hazard points were interpreted, and with field verification, the accuracy rate was 73.2%. Thirty geological hazard points were identified, including 21 landslide hazards, 4 collapse hazards, and 5 unstable slopes. Two typical landslide hazard points showed significant abnormal deformation, with deformation rates ranging from -21 to 21 mm/a and maximum cumulative deformation per point from -25 to 25 mm. These areas are significantly affected by climate, topography, and human activities, posing high-risk hazards. It is essential to strengthen manual inspections, increase monitoring efforts and frequency, and early identification of geological disasters to ensure the safety of engineering construction and other works.

Key words: InSAR, geological disaster identification, surface deformation monitoring, Ordos platform