【作者】 王高峰；

【导师】 唐川；

【作者基本信息】 成都理工大学 ， 地质工程， 2011， 硕士

【摘要】 西藏雅鲁藏布江(米林-加查段)沿线多为高山严寒区,岩石破碎,山体稳定性差,地质构造复杂,地震活动频繁;受季风气候控制,研究区各县段降雨量时空分布不均,冰川、冰湖分布广阔;此外,沿线地表切割强烈,寒冻风化作用强,水土流失严重,加之不合理的人类活动,使该地区的泥石流灾害频繁发生。实地调查研究区沿线共发育有泥石流沟241条,其中暴雨型泥石流188条,冰川型泥石流共53条,冰川型泥石流占泥石流沟总数的22%。通过本文的研究,利用遥感影像与DEM相结合处理分析,总结归纳该区域独有的泥石流灾害、源地物源及冰川、冰湖信息遥感解译特征,进而分析沿线泥石流源地信息分布特征,为泥石流的发展趋势评价提供有用的信息,同时也为西藏山区线性工程的预选线及日后线性工程的改扩建工程具有及大的帮助作用,文章主要得到的结论:1、对研究区沿线泥石流源地物源特征的遥感调查与分析,主要在RapidEye遥感影像数据的基础上把源地物源分为四类进行解译:一类是沟道堆积物,多为第四系松散及古冰川堆积物;第二类是滑坡、崩坡积物体,对这类物源提供泥石流活动的松散物质方量;第三类是森林线与冰蚀线之间的残坡积物,大部分为寒冻弱风化物质;第四类是冰蚀线以上残坡积物,多为寒冻强风化物质。此外,从RapidEye图像还可以清晰的识别泥石流沟道地形特征以及泥石流扇形地形态、面积等特征。2、对研究区沿线泥石流源地冰川、冰湖特征的遥感调查与分析,主要在Landast-7 ETM+多光谱影像数据的基础上,通过光谱波段比值法、主成分分析法、光谱角制图法、非监督分类与监督分类法等五种经典方法的对比验证最后选取一种效果较好的方法对冰川、冰湖信息进行提取。结果表明,监督分类提取的冰川信息图像清晰、层次分明、分类边界清楚、满足冰川地貌解译的要求。3、通过本文基于遥感手段开展了米林至加查段沿线泥石流源地物源及冰川水文信息特征的提取研究与分析的基础上表明:林芝至加查段沿线泥石流源地物源分布具有不均匀性,源地冰川分布具有不平衡性,沿线泥石流源地的物源在冰川融水及冰川型泥石流过后更加发育,积累的松散物质更加丰富,使泥石流源地物源进一步复活并产生大量新物源,从而使沿线泥石流发生频率增高,规模增大。更多还原

【Abstract】 Tibet Brahmaputra (Nyingchi - Add check section), mostly along the cold mountain areas, rock crushing, the mountain poor stability, complex geological structure, seismic activity; by the monsoon climate control, study area, spatial and temporal distribution of rainfall is uneven county section, glaciers, ice Lake broad distribution; In addition, cutting the surface along a strong, strong frost weathering, soil erosion, coupled with irrational human activities, so that the frequent occurrence of debris flow area. Fieldwork in the study area are developed along the debris flow were 241, of which 188 storm debris flow, debris flow on a total of 53 glaciers, glacial debris flow accounted for 22% of the total number of debris flow.Through this study, the use of remote sensing image processing and analysis combined with the DEM, summarized the debris flow hazards unique to the region, the source surface features source and glaciers, glacial lakes interpretation of remote sensing characteristics of the information, and then analyzes the information along the debris flow source distribution, Trends for the evaluation of debris flow provide useful information, but also works for the Tibetan mountains linear linear pre-line and future projects and the renovation and expansion project with the help of a large role, this paper concluded:1. The source of the study area along the debris flow source characteristic surface features and analysis of remote sensing survey, mainly in the RapidEye high-resolution remote sensing data based on the source surface features to interpret the source is divided into four categories: one is the channel deposits, Mostly loose and ancient glacial Quaternary deposits; second is the landslide, avalanche slope plot objects to provide this type of source material side of loose debris flow volume; The third line of the forest line and between glacial Residual slope sediments, most chilling weakly weathered material; The fourth category is the residual slope above the glacial sediments, mostly frost weathered material. In addition, from RapidEye image of debris flow can be clearly identified and the debris flow fan channel topography to shape, size and other features.2. The study area along the debris flow source glaciers, glacial lakes investigation and analysis of remote sensing feature, mainly in the Landast-7 ETM + multispectral image data, based on the ratio method by spectral bands, principal component analysis, spectral angle mapping method, Unsupervised classification and supervised classification methods such as comparison of the five classical methods verify the final selection of a better way of glaciers, glacial lakes information extraction. The results showed that the glacier supervised classification of information extracted image is clear, structured, clear classification of the border, to meet the requirements of glacial landform interpretation.3. Carried out by means of this remote sensing investigation section Nyingchi to add surface features along the debris flow source of information sources and glacier hydrology study and analysis of feature extraction based on the show: check section Nyingchi to add surface features along the debris flow source with a uniform source distribution Nature, source uneven distribution of glaciers, the source of the material along the debris flow source in the glacial melt water and glacial debris flow after more development, more abundant accumulation of loose material, debris flow source to source further revival of surface features and produce a lot of new material Source, so that the increased frequency of landslides along the scale increases.更多还原