Application of Key Technologies in Detailed Geological Hazard Risk Investigation and Analysis of Hazard Development Mechanisms in Western Sichuan Region—A Case Study of Heishui County

Detailed geological hazard risk investigation is of great significance for the scientific and effective prevention and control of geological hazards. Aiming at the geological hazard risks under the complex geological environment of western Sichuan, this study systematically and quantitatively analyzed the hazard-inducing conditions, hazard characteristics, and controlling factors of geological hazards in Heishui County through a technical system of "multi-source data fusion-remote sensing interpretation-high-precision monitoring-field verification," and deeply revealed the regional hazard development mechanisms. The results show that: the InSAR monitoring areas with annual deformation rates of 47–89 mm/a have a 92% consistency with field verification; the remote sensing interpretation accuracy rates for landslides (68 sites) and debris flows (5 sites) are 87%; the geophysical prospecting-drilling joint inversion effectively defines the weak sliding zone of strongly weathered sandstone-slate (resistivity 50–200 Ω·m, cohesion 10–25 kPa); and hazard development is synergistically controlled by "slope gradient of 35°–45°-strongly weathered sandstone-slate-daily rainfall ≥50 mm." The research results provide scientific support for regional disaster prevention and technical reference for detailed geological hazard investigation in alpine regions.