基于GIS和信息量模型的广西花岗岩分布区滑坡易发性评价

摘要

Landslides are frequent in granite area of Guangxi Province,where rock structure is loose,weathered clinosol and residual soils are thick and distributed widely,and rainfall is abundant.Based on statistics,the indexes of landslide susceptibility evaluation are selected, including slope, elevation, geological structure, vegetation,rainfall and human engineering activities.The landslide susceptibility in the granite area is divided into districts,based on ArcGIS software and information model.The landslide susceptibility evaluation results are compared with the existing landslides and hidden troubles in the granite area.The comparison result shows that the susceptibility assessment is correct and can be used for the forecasting of landslide and early warning in the granite area.%广西花岗岩分布区的岩土体结构松散，分布有大量较大厚度的风化坡残积土，受侵蚀、剥蚀、切割作用强烈，局部的水土流失严重，而且该区降雨量丰富，经常会有滑坡地质灾害发生。在统计分析的基础上选取坡度、高程、地质构造、植被、降雨、人类工程活动、滑坡灾害体积密度作为易发性评价指标，基于ArcGIS软件并运用信息量模型对广西花岗岩分布区进行滑坡易发性区划、完成滑坡易发性评价，并与滑坡灾害点和隐患点进行了验证。广西花岗岩区滑坡易发性评价的结果与实际滑坡的分布较为吻合，为广西花岗岩分布区滑坡预警预报及防治工作奠定基础。