鄂西归州-泄滩地质灾害时空分布特征及形成条件分析

鄂西山区历来是地质灾害高发区域,随着近年来重大工程建设的开展,三峡库区175m蓄水,南方强降雨等极端气候的影响,大量地质灾害发生变形破坏乃至失稳。本文在1∶50 000区域地质灾害调查的基础上,通过成果资料数据统计,梳理出研究区地质灾害数量、类型、规模等发育特征,同时对其时空分布特征和形成条件进行系统分析。分析表明:地质灾害的分布与地貌有密切的关系,地质灾害多发育在高程300~800m、坡度20°~40°的范围内;70%以上灾害发育在侏罗系蓬莱镇组(J3p)、遂宁组(J3s)和沙溪庙组(J2s)岩性段中,且顺向结构岸坡中地质灾害最为发育;地质灾害具有沿主要构造断裂两侧呈条带状分布的特征。通过走访、现场调查掌握了诱发地质灾害主要自然因素为降雨和库水波动,人为因素为人类工程活动。依据地质灾害目前现状和发展趋势,提出对策建议,以期为该区域地质灾害防治提供参考。

ANALYSIS ON TEMPORAL-SPATIAL DISTRIBUTION AND FORMATION CONDITIONS OF GEOHAZARDS IN WESTERN OF HUBEI PROVINCE

It is always has been a high incidence area of geological disasters in Western hu-bei mountainous area,with the development of major projects in recent years,175 m water storage in Three Gorges Reservoir area and Influence of extreme climate such as heavy rain-fall in South china,a large number of geohazards deformation damage and instability.Based on the investigation of geological hazards in the 1∶50 000 area,through the results of data statistics,to sort out the development characteristics of the quantity,type and scale of geo-hazards in the study area,At the same time,the spatial and temporal distribution character-istics and the formation conditions of the system were analyzed.Analysis shows:the distri-bution of geohazards has close relationship with landform,geohazards more development in elevation 300~800 m,20°~ 40°slope range;more than 70% of the geohazards are in the Jurassic (J3 p),(J3 s)and (J2 s),and the consequent slope in geoazards structure is the most important;geohazards have the characteristics of strip distribution along the main structural faults.The main natural factors of the geological hazards are the rainfall and the fluctuation of reservoir water through the visit and the field investigation,Human factors for human en-gineering activities.According to the current situation and development trend of geohazards, put forward countermeasures and suggestions,In order to provide reference for the preven-tion and control of geological disasters in the region.