Movement characteristics and formation mechanism of the "6·10" Pengjiadong high speed landslide in Xingren

Abstract

At approximately 20:30 on June 10, 2021, a high-speed landslide occurred in Pengjiadong in Xingren. The landslide mass moved at a high speed and scraped the slope collapse accumulation along the way, killed 3 people and damaged 18 houses. Through remote sensing interpretation of image data before and after the landslide, detailed geological investigation of the disaster site and indoor comprehensive analysis, the characteristics of the landslide were described in detail, and the movement characteristics and formation mechanism of the landslide were clarified. The research shows that the slope terrain with the feature of "steep up-moderate slow down-steep down" and the geotechnical structure with the feature of "hard up and soft down" were the internal factors of the landslide, while human engineering activities, saturated loading of heavy rainfall and infiltration softening were the external factors of the landslide. The plane shape of the landslide was polygonal. According to the movement characteristics and accumulation structure, the landslide was divided into three areas: sliding source area (Ⅰ), shoveling-circulation area (Ⅱ) and shoveling accumulation area (Ⅲ). The landslides was a high-speed compression-push landslide formed by the formation of dangerous rock zones, landslide initiation and slope collapse. The research shows that the in-depth study of the movement characteristics and disaster formation mechanism of the Pengjiadong landslide has a strong guiding role for disaster prevention and reduction in similar slope areas and geotechnical structure areas in Guizhou.

Keywords

• high speed landslide
• collapse deposit
• movement characteristics
• formation mechanism
• formation and evolution of landslide