Detection of potential landslides in the section from Kagong County to Rumei Town of Lancang River based on InSAR technology

The section from Kagong Gounty to Rumei Town of Lancang River is located in the southeast of Qinghai-Tibet Plateau, with high altitude, deep-cutting valley, unrolling terrain and rich in hydraulic resources. Because of the complex geological structure in this region, there are many high-position geological hazards, which seriously affect the safety of downstream hydropower station construction. The potential landslides within 5 km of the main stream of the Lancang River from Kagong County to Rumei Town section were detected using Stacking-InSAR technology to ensure the safety construction of hydropower stations downstream. The quantity and distribution characteristics of potential landslides in the study area were obtained, and typical potential landslides were selected to analyze their deformation characteristics in time series. The results show: ① A total of 149 potential landslides were detected by ascent and descent orbit images in the study area, with characteristics of free surface development and less vegetation coverage. The landslide surface is full of gully,and shallow collapse occurred in partial areas with serious erosion and loose structure. ② The potential landslides in the study area are mainly rockfalls and landslides, with a total of 54 potential rockfalls and 95 potential landslides. ③ In the study area, most of the potential landslides show multistage sliding trend and are in uniform deformation stage. However, the average annual deformation rate and cumulative deformation in the line of sight are large, indicating that the slope is unstable and poses a great threat to residents along the Lancang River and the construction of hydropower stations downstream.