基于RS和GIS的炉霍县地质灾害危险性评价

发布时间：2018-04-30 04:07

本文选题：RS + GIS　；参考：《西南交通大学》2015年硕士论文

【摘要】：近些年来,我国地震活动强度和频度较高,常常诱发滑坡、崩塌、泥石流等地质灾害,尤其发生在山区的地震,谷深坡陡,造成的地质灾害更为严重。这也使加大防灾减灾的力度显得重要,以降低灾害的风险和造成的损失。因此,将最新的RS和GIS应用到地质灾害研究成为必然趋势。本文以四川西部的炉霍县作为研究区,结合RS和GIS技术,研究滑坡、崩塌、泥石流等主要地质灾害的在时间、空间和强度三方面的发育和分布规律,选取合适的致灾因子(包括工程岩性、气候因子、地形因子等)。在此基础上选定科学的评价模型,确定评价因子的权重,进行地质灾害危险性评价；对评价结果进行分区,分析出各区的地质灾害特征,并统计各区地质灾害个数和规模等信息；利用分析评价结果,指导炉霍县地质灾害的防治。通过本文的研究,最终取得以下成果：(1)通过遥感影像和实地调查,查明了炉霍县地质灾害的类型、分布规律和发育特征。炉霍县发育的地质灾害类型主要包括泥石流、滑坡、不稳定斜坡与崩塌；受气象水文条件、地形地貌、地层岩性、地质构造及人类工程活的影响,研究区内地质灾害点分布呈“Y”字形,和泥曲河、达曲河、鲜水河所成的“Y”字形水流相吻合,微地貌多为河谷；具有种类少、数量多、规模中等偏小、分布不均、危害性较大的特点。(2)通过调查分析,确定岩性组合、地形地貌在诸多因素中占主导地位,它决定了地质灾害发生的能量的转化条件和动力大小,松散碎屑沉积物的聚集和成灾的可能性。降雨量、植被覆盖率、人类工程活动等因子对地质灾害的形成和发展有着激发和促进作用,选择高程、坡度、坡向、水系、土地利用现状、工程岩组、断裂、灾害点现状作为地质灾害危险程度的致灾因子。(3)根据选取的致灾因子结合层次分析法,在ArcGIS软件中利用模型构建器建立了炉霍县地质灾害危险性评价模型,对炉霍县地质灾害危险性进行危险性分区,将全区划分为4个区、11个亚区,其中3个地质灾害高危险区、4个地质灾害中危险区、3个地质灾害低危险区及不危险区。(4)根据炉霍县地质灾害危险程度分区成果,充分考虑炉霍县国民经济区域总体规划布局特点,按地质灾害防治原则,协助炉霍县政府主管部门制定炉霍县地质灾害防治区划。根据国土资源部《县(市)地质灾害调查与区划基本要求》实施细则共划分重点、次重点和一般、次一般4个级别的防治区。
[Abstract]:In recent years, the intensity and frequency of seismic activities in China are relatively high, which often induces geological disasters, such as landslides, collapses, debris flows and so on, especially in mountainous areas, where the slope is steep and the geological disasters are even more serious. This also makes it important to increase disaster prevention and mitigation in order to reduce disaster risks and losses. Therefore, it is an inevitable trend to apply the newest RS and GIS to the study of geological hazards. Taking Luhuo County in the west of Sichuan as the research area and combining RS and GIS technology, this paper studies the development and distribution law of the main geological hazards, such as landslide, collapse and debris flow, in three aspects: time, space and intensity. Select appropriate disaster factors (including engineering lithology, climate factors, terrain factors and so on). On this basis, the scientific evaluation model is selected, the weight of the evaluation factors is determined, the geological hazard risk assessment is carried out, the evaluation results are divided, and the geological hazard characteristics of each district are analyzed. The number and scale of geological hazards in each district are counted and the results of analysis and evaluation are used to guide the prevention and treatment of geological hazards in Luhuo County. Through the research of this paper, the following results are obtained: 1) through remote sensing image and field investigation, the types, distribution and developmental characteristics of geological disasters in Luhuo County are found out. The types of geological hazards developed in Luhuo County mainly include debris flow, landslide, unstable slope and collapse, influenced by meteorological and hydrological conditions, topography and geomorphology, stratigraphic lithology, geological structure and human engineering activity. The distribution of geological hazard points in the study area is "Y" shaped, consistent with the "Y" zigzag flow formed by Niqu River, Daqu River and Xianshui River, and the microgeomorphology is mostly river valley, with small species, large quantity, medium small scale and uneven distribution, Through investigation and analysis, the lithologic combination is determined, and topography and geomorphology play a dominant role in many factors, which determines the energy conversion conditions and power of geological disasters. The accumulation of loose clastic sediments and the possibility of disaster. The factors such as rainfall, vegetation coverage, human engineering activities and other factors can stimulate and promote the formation and development of geological disasters, and select elevation, slope, slope direction, water system, land use status, engineering rock formation, fracture, etc. According to the selection of hazard factors combined with the Analytic hierarchy process (AHP), the hazard assessment model of geological hazards in Luhuo County is established by using the model builder in ArcGIS software. The hazards of geological hazards in Luhuo County are divided into 4 regions and 11 sub-regions. Among them, 3 are high risk areas of geological hazards, 4 of them are dangerous areas of geological hazards, 3 of which are low risk areas of geological hazards and 3 of non-dangerous areas) according to the results of zoning of geological hazard risk degree in Luhuo County, According to the principle of geological disaster prevention and control, the government department in charge of Luhuo county should be assisted in drawing up the regionalization of geological hazard prevention and control in Luhuo county. According to the implementation rules of the Ministry of Land and Resources < the basic requirements of County (City) Geological Hazard Survey and regionalization >, the prevention and control areas of the four levels are divided into four levels: key, secondary, general and sub-general.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P694

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