RESEARCH PROGRESSES ON LANDSLIDE DISASTER PATTERNS AND THEIR RESPONSE TO GEOMORPHIC EVOLUTION IN MEIGU RIVER BASIN

The Meigu River Basin is located in the transition zone between the Yunnan-Guizhou Plateau and the southwestern Sichuan Mountains in the eastern edge of the Qinghai-Tibet Plateau,where landslides are the most intensive in the world. The giant and super large-scale landslides are widely distributed. They are numerous,have complex mechanisms and can be serious harmful in the region due to the types of special landform evolution. They have become a major safety hazard for road safety,rural revitalization and urban construction in river valleys. Therefore,some scientific responses are urgently needed to deal with them. On the basis of many years of ancient landslide research in China and abroad,the authors summarize the research progress with temporal and spatial distribution of ancient landslides in Meigu River Basin,the response of landslides to tectonic landforms,the disaster-pregnancy mechanism of landslide,and the pattern of landslide-induced disaster and the main controlling factors. Combined with the actual needs of disaster prevention and mitigation of landslides,three key scientific issues in the disaster-pregnancy patterns of ancient landslides under the control of tectonic landforms in the Meigu River Basin are proposed. (1)The disaster-pregnancy and disaster-control pattern of landslides caused by different developmental coincident tectonic landforms; (2)The disaster-pregnancy patterns of large-scale landslides due to coincident tectonic landforms in the tectonic uplifting differences area; (3)Establishment of the corresponding relationship among faults,folds,ancient earthquakes and paleoclimate change and landslide development,to reveal the genetic mechanism of ancient landslides in Meigu River Basin. The solution of the above key scientific problems would play a positive guiding role in the study of ancient landslides and disaster prevention and mitigation in the southwestern mountainous area.