Disaster-Prone Conditions and Formation Mechanisms of Debris Flow Geological Hazards in an Area of Xizang

This study systematically summarizes the development characteristics of debris flows in an area of Xizang by integrating historical survey data and the latest field investigation results. A mathematical statistical approach is employed to analyze the geological disaster-prone conditions of debris flows within the area, focusing on multiple factors, including watershed area, relief amplitude, slope gradient, relative height difference, Melton ratio, and landslide density, to reveal the mechanisms of disaster formation. The findings indicate that the disaster-prone conditions for debris flows in this area are complex. Moderate watershed areas, significant relief amplitudes, steep slopes, pronounced relative height differences and Melton ratios are identified as key factors contributing to the high frequency of debris flows. The mechanisms of debris flow formation can be categorized into two primary types: rainfall-induced and avalanche-induced. The disaster-causing patterns of debris flows are diverse, with three main types identified: erosion and impact type, burial type and blockage type. Each type exhibits distinct destructive mechanisms and impact slope. To reduce disaster losses, it is essential to develop scientific prevention and mitigation strategies based on the characteristics of debris flows, integrating geotechnical engineering and bioengineering measures. The research results aim to provide a scientific basis for the risk management of geological disasters in the region, and provide references for the disaster management in similar geological background areas.