秦巴山区地质灾害发育规律研究--以镇巴县幅为例

STUDY ON THE DEVELOPMENT REGULARITY OF GEOHAZARDS IN QINLINGDABA MOUNTAINS:A Case Study of Zhenba County,Shaanxi Province

以镇巴县幅为例,通过现场地质灾害调查、无人机航拍、室内遥感解译的方法,统计斜坡地质灾害的分布与地貌、坡度、坡向、斜坡结构类型、水系与公路的相关性,得出以下结论:1)斜坡灾害发育与地貌紧密相关,低山区与中山区斜坡地质灾害占灾害总数的96.97%.2)斜坡灾害主要分布在20~40°坡度区间内,灾害数目占总斜坡灾害数目的75.76%.3)41%的斜坡灾害分布在东、西两个方向斜坡上.4)顺向坡最易发育地质灾害,顺向坡地质灾害数量占总数的33%.5)河流对地质灾害有很强的控制作用,45.45%的地质灾害发生在距河流200 m范围内.6)研究区内斜坡灾害与人类工程活动特别是修建公路有很强的相关性,公路两侧50 m范围内发育斜坡灾害数量占总数的55.56%.结合研究区地质灾害发育规律及遥感影像特征,总结出一套适用于陕南秦巴山区的斜坡灾害识别方法,可为防灾减灾及灾害识别提供技术支持.

Taking Zhenba County as an example,the correlation between slope geohazard distribution and landform,gradient,aspect,structure type,water system and road are analyzed through field geohazard survey,UAV aerial photography and indoor remote sensing interpretation.The conclusions are shown as follows:1)The development of slope hazards is closely related to landform,with slope hazards in low and middle mountains accounting for 96.97%of the total disasters.2)Slope hazards are mainly distributed in gradient of 20-40°,accounting for 75.76%of the total.3)Of slope hazards,41%are distributed on the east and west slopes.4)Bedding slope is the most prone to geohazards,accounting for 33%of the total.5)Rivers have a strong control on geohazards,with 45.45%of the geohazards occurred within 200 m from the river.6)Slope hazards in the study area are significantly correlated with human engineering activities,especially road construction.The slope hazards developed within 50 m on both sides of roads account for 55.56%of the total.Moreover,combined with the development regularity of geohazards and characteristics of remote sensing images in the study area,a set of slope disaster identification methods applicable to Qinling-Daba Mountains in southern Shaanxi Province are summarized,which provides technical support for disaster prevention,mitigation and identification.