Landslide inventory and distribution patterns in Lhasa area, Tibet Plateau

As the capital of the Tibet Autonomous region, Lhasa plays a pivotal role as the political, economic, cultural, and educational center of Tibet. Therefore, compiling a comprehensive landslide inventory and analyzing their spatial distribution patterns holds significant importance for mitigating and preventing landslide disasters in this area. This study focuses on Lhasa, Tibet, utilizing high-resolution satellite imagery for landslide interpretation and delineation to establish a detailed landslide inventory map for Lhasa area. We also analyzed the spatial distribution of landslides within the study area and the influencing factors contributing to their occurrences. The result shows that a total of 3709 landslides were identified in the Lhasa region, with a combined area of approximately 718.14 km2. Overall, the predominant landslide types were deep-seated rockslides, and a few rock avalanches, rotational landslides, and debris flows. The landslides of Lhasa area exhibited a clustered pattern with the majority concentrated in the central part of the study area, particularly in the vicinity of Linzhou County. Additionally, regions near the Yadong-Gulong fault and Namco southeast bank fault were also identified as landslide abundance area. The relationship between landslide and different influencing factors show that landslides are predominantly found in the elevation range of 4300–5300 m and relief between 1100 and 1500 m. Landslide abundance index consistently increases with a rise in hillslope gradient. Particularly, the Triassic (T1 − 3) lithological unit exhibits the highest LAD at 3.5%, indicating a higher likelihood of landslides in this lithological unit. Combining historical earthquake data with interpreted landslide scale, we suggests that the majority of large-scale landslides in Damxung area were triggered by the 1411 Ms8.0 Damxung earthquake.