Analysis on the distributive characteristics and causes of the geological disasters induced by the “8·8” heavy rainstorm in Qu County, Sichuan Province

Abstract

On August 8, 2021, Quxian County was hit by a heavy rainstorm, causing 38 new disasters and aggravating 109 existing disasters to varying degrees. Based on field survey , this paper studies the characteristics of disasters caused by heavy rainstorms and the relationship between the hazard including and geological conditions and disaster distribution. The results show that: the new disaster points caused by the heavy rain in Quxian County are mainly soil landslides, accounting for 94.7%; the regional slope structure has the highest impact on the disaster occurrence; Soil landslides occurred in 300～325 mm accumulative rainfall range, up to 27 places; There are 23 disaster points with serious signs of aggravation of deformation, which are distributed in the range of accumulative rainfall of 337～348 mm; It can provide a scientific basis for the county’s geological disaster prevention and control zoning and flood season geological disaster prevention, and can provide a reference for disaster prevention and mitigation of geological disasters in similar areas with heavy rainstorms.

Keywords

• heavy rain
• geological disaster
• landslide
• disaster-pregnant geological conditions
• cumulative rainfall