Study On Geohazard Division And The Plan Of Control In Huaihua City Of Hunan Province

Combined with the work of geological hazard survey project "The risk zoning of Geological Hazard in the Huaihua city of Hunan province" issued by the Ministry of Land and Resources in the Huaihua city, the article introduces the general condition of the nature geography, and illuminates the characteristics of the geological hazards in Huaihua city. Then it analyses the forming condition of the disasters of debris flow, collapse, landslide, etc. Main results are summarized as follows:Firstly, based on the field survey and the references, we found that the geological hazards in HuaiHua city mainly include landslide, collapse, debris flow, land collapse (karst collapse and mining collapse) and ground fractures. It was found that there were 872 places of geological hazards in Huaihua city. The number of landslip, collapse, debris flow, karst collapse, mining collapse and ground fractures are 731, 51,21,44,13 and 12 in the all 872 places of geological hazards.Secondly, through the analysis of formation conditions of various types of geological hazards and the influence factors, using quantitative analysis as dominant, quantitative analysis as assistance, supplemented by the method of combining qualitative analysis and quantitative evaluation, five high probability risk zones, five medium probability risk zones, one low probability and security risk zone were divided.Thirdly, according to the geological environmental formation conditions of geological hazards and geological characteristics of geological-hazard-prone-areas, combined with Huaihua national economic and social development plan, a comprehensive analysis was carried out and the Huaihua city was divided into three-grade zones including five key preventing zones, three secondary preventing zones and one general preventing zone.The end, considered the danger degree of the geological hazard, combined with the danger degree of important projects, present projects, settlements, important nature reserves, human landscape areas and so on, three key pre-warning areas, four secondary pre-warning areas and two general pre-warning areas were divided.