MAIN GEOHAZARD TYPES AND THEIR OCCURRENCE CHARACTERISTICS ALONG THE YUNNAN-TIBET RAILWAY IN NW YUNNAN

The Yunnan-Tibet Railway in NW Yunnan is located at the transitional position of the southeastern Qinghai-Tibet Plateau to Yunnan-Guizhou Plateau,where landforms are complex,valleys are deeply incised,neotectonic movement is very intense and earthquakes occur frequently.The precipitation in the area is mainly recorded in May to October,when the rainfall is high and centralized.Because of the complex geological environment,combined with rain,human activities and other exterior factors,the area becomes an area of repeated occurrence of geohazards such as landslides,debris flow and avalanches,which often cause traffic interruption,destroy houses and cause casualties.On the basis of field geological investigations,the authors focus on the main geohazard types and their occurrence characteristics along the Yunnan-Tibet railway in NW Yunnan,which have important theoretical and practical significance for mitigating and preventing geohazards such as landslides,debris flows and avalanches that the railway might suffer.