Analyzing the formation mechanism of the Xuyong landslide, Sichuan province, China, and emergency monitoring based on multiple remote sensing platform techniques

Abstract

In this study, multitemporal satellite images, unmanned aerial vehicle (UAV) photogrammetry and ground-based radar were utilized to investigate the formation mechanism and disaster features of different phases of the Xuyong landslide disaster that occurred in Sichuan Province on December 9, 2018. Field survey indicates that the estimated landslide volume is approximately 35000 m3. The landslide is a typical dualistic soil-rock structural landslide with bedding planes. The sliding surface is located in a thin layer of limestone which is characterized by the X-shaped conjugate joint planes. The steep slope has been cut and transformed by human disturbances, which have influenced the slope stability and the drainage of precipitation along the slope. Many factors, including the regional geological structure, stratum lithology, slope topography, landform morphology, and precipitation, have contributed to the Xuyong landslide during the pre-disaster phase. Post-disaster emergency observation revealed that subsequent deformation was located mainly along the back edge of the landslide, where the maximum surficial deformation reached only 18 mm/day over a small area, reflecting the low probability of a secondary landslide hazard. Our research provides significant guidelines for investigating potential landslide dangers in similar environments and for post-disaster emergency response using multiple remote sensing (RS) platforms.