Comprehensive investigation and kinematic assessment of a small catastrophic landslide in Shiban Valley, Leshan City, Sichuan Province, China
摘要
On June 4, 2023, a small-scale landslide occurred in Shiban Valley, Jinkouhe District, Leshan City, Sichuan Province, China. The Shiban Valley landslide destroyed a miners’ dormitory and resulted in 19 casualties. The sliding material traveled at a maximum distance of approximately 280 m with a total volume of approximately 2 × 104 m3. In this study, comprehensive field investigations are conducted to gain insight into the characteristics, causes, and restoration measures of the Shiban Valley landslide. The runout process is revealed through a combined analysis of RAMMS numerical simulations and landquake signal inversion. The results indicate that the Shiban Valley landslide is likely the result of a combination of natural geographic conditions, hydrometeorological factors, and engineering works. The numerical results are verified with landquake signals and field investigations, and show that the Shiban Valley landslide travels a maximum distance of 291 m in 99.7 s, with a peak velocity of 16 m/s. The simulated sliding mass begins with a volume of 1.18 × 104 m3 and results in a total deposition volume of 1.83 × 104 m3 and average depth of 8 m, which exhibits obvious erosion effect. The runout evolution process can be divided into four phases (sudden onset, impact shoveling, main deposition, and trailing end accumulation), and each phase exhibits distinct frequency characteristics. The findings of this study provide a significant reference for future prevention, mitigation, and early warning of similar landslides in this area. The characteristics and restoration measures of the Shiban Valley landslide may also serve as a reference for the management of similar landslides.