河南省不良地质灾害分布特征及其影响机理

Distribution characteristics and influence mechanism of adverse geological hazards in Henan Province

为查清河南省地质灾害分布特征及其影响机理,通过现场调查、资料搜集分析等方式对河南省不良地质灾害点分布特征进行统计分析,基于ArcGIS对其分布特征及规律进行厘定。在此基础上,对地形地貌(坡型、坡度、坡高)、岩土体类型及结构、地质构造以及降雨等因素对地质灾害的发育规律影响进行分析。结果表明,河南省地质灾害主要分布在河南省中西部南阳市、洛阳市、三门峡市等地区,以崩塌、滑坡为主,占总数的80%以上;正向类坡型形成滑坡概率为负向类坡型的3倍,在坡度为23°~52°、高度小于20 m时斜坡内滑坡发育概率最大;崩塌随坡度增加发育概率增加,随高度增加发育概率减小;河南省地表岩土体类型中黏性土占比最大为40.16%,但地质灾害在黄土类土发生地质灾害的占比最高为23.46%,其次为变质岩中的18.46%;至断裂构造距离为0~2.5、2.5~5、5~7.5、7.5~10、>10 km共5个缓冲区内地质灾害分布占总样本数的比例分别为18.85%、18.11%、17.84%、20.89%及24.31%,河南省地质灾害多集中分布在年平均降雨强度在600~800 mm区域,占比达80%。研究结果对河南省电网等相关工程选线、选址等考虑地质灾害影响具有一定借鉴及指导意义。

In order to investigate the distribution characteristics and influence mechanism of geological hazards in Henan Province.Field investigation,data collection and analysis were used to analyze the distribution characteristics of geological disaster sites in Henan Province.ArcGis was also used to determine the geological disaster sites distribution characteristics and laws.The influence of landform(slope type,slope angle,slope height),rock and soil body type and structure,geological structure and rainfall and other factors on the geological disaster sites distribution laws were studied.The results show the geological disasters are mainly distributed in Nanyang City,Luoyang City,Sanmenxia City and other areas in the central and western part of Henan Province,collapse and landslide are the mainly types,which accounts for 80% of the total.The probability of landslide formation in positive slope type is 3 times than that of negative slope type,and the probability of landslide development in slope is the largest when the slope is 23°~52°and the height is less than 20 m.The development probability of collapse increases with the increase of slope and decreases with the increase of height.Cohesive soil accounts for the largest proportion of 40.16% in the surface rock and soil types in Henan Province,however,the degree of geological disaster development in loess soil takes the most proportion of 23.46%,and 18.46% in metamorphic rocks.The development of geological hazards within 0~2.5、2.5~5、5~7.5、7.5~10、>10 km from the fault structure accounts for 18.85%、18.11%、17.84%、20.89% and 24.31%,respectively.Geological disasters in Henan Province are mainly distributed in areas with average annual rainfall intensity of 600~800 mm,accounting for 80%.The research results have important guiding significance for selecting lines and stations in the early stage of Henan power grid project and et al.