Preliminary study on the characteristics of landslides and soil liquefaction triggered by the Tingri M_s6.8 earthquake on January 7, 2025, Southern Tibetan Plateau

Using remote sensing images for rapidly mapping secondary effects triggered by strong earthquakes is critical for understanding the disaster-causing mechanisms. The Tibetan Plateau， characterized by high altitude， sparse population， and challenging field conditions， poses significant challenges for on-site investigations. Therefore， utilizing post-earthquake emergency satellite imagery to extract coseismic landslides and soil liquefaction is of excellent research significance. We focused on mapping secondary hazards (landslides and soil liquefaction) triggered by the Ms 6.8 Tingri earthquake on January 7， 2025. We employed high-resolution Chinese satellite imagery and conducted manual-visual interpretation through a comparative analysis of pre- and post-earthquake images. The following key findings were obtained: (1) The mainshock triggered 2，869 coseismic landslides， predominantly manifesting as slope debris flows and rock collapses， of which about 60% occurred at an altitude of 5，000～6，000 m， which had limited direct impact on residential areas due to the sparse population located in the valleys. (2) The mainshock also induced 400，000 soil liquefaction pits， which were primarily concentrated in the floodplains and low terraces of the Pengqu River at elevations of 4，100～4，300 m. These liquefaction sites were widely distributed across the Dengme Co Basin， Guojia Basin， and Dinggye Basin， with some occurrences reaching elevations of ～5，200 m in Quaternary tills. The distribution pattern of coseismic landslides， dominated by slope debris flows in high-altitude mountainous regions， suggests a potential correlation with topographic amplification effects. In contrast， the coseismic soil liquefaction， predominantly concentrated within the floodplains and three fault-controlled basins along the Dinggye-Shenzha Rift System， reveals that a single sub-faulted rupture can trigger similar secondary effects in adjacent basins even without surface faulting. This finding emphasizes the widespread cascading effects of fault rupture events， we should pay special attention to the chain effect of strong earthquake disasters in the Southern Tibetan Rift system.