四川泸定MS6.8级地震诱发崩滑灾害快速评估

强震诱发崩滑灾害可严重加剧地震灾害损失，快速评估地震诱发崩滑分布对于应急救灾工作部署具有重要意义。利用2022年9月5日泸定M_S6.8级地震震前30 m分辨率地形数据结合1∶50万比例尺地质图，采用Newmark累积位移方法开展了泸定地震诱发崩滑灾害快速评估。结果显示：(1)地震诱发崩滑灾害较为严重，崩滑高危险区面积约为45 km²，主要分布在鲜水河断裂以西大渡河西岸近东西向支沟两岸，其中以燕子沟、磨子沟、海螺沟、飞水沟、湾东河、什月河、田湾河等崩滑危险性较高，对沟内居民及游客生命安全威胁较大，沟内公路受崩滑阻断风险较高，局部河道有被崩滑堵塞风险；(2)泸定县冷碛镇、兴隆镇、磨西镇、得妥乡等4个乡镇及石棉县田湾乡、草科乡、新民乡、先锋乡、蟹螺乡、挖角乡等6个乡镇崩滑危险性较高；(3)震中附近地区大渡河沿线省道S434和S211受崩滑阻断可能性较大；(4)贡嘎雪山一带预测地震崩滑危险性为中等，但需关注冰崩型、岩崩型高位远程灾害(链)风险。通过与震后应急排查、遥感解译等获取的地震Ⅷ度、Ⅸ度区内发生的崩滑分布对比，表明在大渡河西岸各支沟滑坡位移分析...

Emergency rapid assessment of landslides induced by the Luding MS6.8 earthquake in Sichuan of China

Seismic landslides can seriously aggravate the losses of earthquake disasters. Therefore, it is of great significance to assessment the distribution of earthquake induced landslides for emergency relief. In this paper, based on the 30 m resolution DEM and regional geologic data with a scale of 1∶500 000, emergency rapid assessment of earthquake induced landslides is carried out using the Newmark cumulative displacement model for the 5 September 2022 Luding M_S6.8 earthquake, China. The results show that the earthquake induced landslides are relatively serious in this earthquake. The high hazard zones of the coseismic landslides are about 45 km2, which is mainly distributed on the two banks of the nearly east-west tributaries on the west bank of the Dadu River and the west of the Xianshuihe fault, especially along the Yanzigou, Mozigou, Hailuogou, Feishuigou gullies and the Wandong, Shiyue, Tianwan rivers, posing a great threat to the lives of residents and tourists. The rivers and roads in these tributaries are at high risk of being blocked by landslides. The Lengqi, Xinglong, Moxi and Detuo towns in Luding County and Tianwan, Caoke, Xinmin, Xianfeng, Xieluo and Wajiao towns in Shimian County are at high risk of landslides. The S434 Provincial Road and S211 Provincial Road along the Dadu River near the epicenter are more likely to be blocked by landslides. The predicted earthquake landslide hazard in the Gongga Snow Mountain area is medium, but it is necessary to pay attention to the risks of long range and high position landslide disaster (chain), such as ice avalanche and rock avalanche. Comparison between the distribution of induced landslides in zones with intensity VIII and IX obtained from post-earthquake emergency investigation and remote sensing interpretation shows that the obtained displacements can well reflect the macro distribution of coseismic landslides along the tributaries on the west bank of the Dadu River, but cannot be exerted effectively around the edge of the Moxi platform and the banks of the main stream of Dadu River, which can be enhanced through the improvement of large scale of geologic maps and high quality topography data. The results can provide reference for valuable timely reference information on post-earthquake reconstruction planning and long-time activity of post-earthquake geohazard and risk recognition of landslide disaster chains.