Research On The Developmental Characteristics And The Regularities Of Space-time Distribution Of Landslide In Pingshan County

Pingshan county lies on the southern edge of Sichuan province,Jinsha river north shore,complicated landform,as the extreme weather, the population,the resources,the environmental conflict intensifies,human engineering activity has increased,geological disasters are becoming more and more prominent.The type of geological disaster in pingshan county includes:Landslides, unstable slopes, avalanches and mudslides.At present, there are 278 geological disasters in the county,the landslide in 241,landslides account for nearly 90 percent of all geological disasters.This paper takes the landslide geological disaster in Pingshan county as an example, by identifying the geological conditions of the landslide, the development characteristics,induced factors and forming mechanism of various landslides are analyzed ; combining the location of the landslide, regularities of space-time of landslide in the county was summarized. The main ideas are the following.(1) The development characteristics of landslide in Pingshan county. The landslide was distributed in all townships in pingshan county, It has the characteristics of small size,wide distribution, concentration of outbreak period and relatively high risk. The landslide is dominated by small and medium, soil, shallow and traction type; rainfall is the main cause of the landslide; the present situation and trend of the landslide are mainly based on basic stability.(2) The regularities of space-time distribution of landslide in Pingshan county. Heavy rainfall, frequent flooding and strong years of human engineering, frequent landslides; the steady state of landslide changes with the changing seasons and the periodic changes of rainfall. Jinping town, Longxi township and Taiping township have the highest density of landslides; the landslide is mainly developed in the low mountain terrain of Jurassic strata,which is 500?800m above sea level, the slope ? 100 meters, gradient between 10° and 30 °, the slope form is dominated by convex and ladder type; the landslide is mainly distributed in areas below 1050mm, and it grows in a ribbon along the river system.