【作者】 杜军；

【导师】 薛重生；

【作者基本信息】 中国地质大学 ， 资源与环境遥感， 2010， 博士

【摘要】 地震次生地质灾害是指由地震活动引起的地质灾害。地震次生地质灾害增强了地震灾害的破坏效应,加剧了地震的损失程度,因此次生地质灾害危险性评价是地震灾害情评估工作的重要组成部分,在地质灾害危险范围预测、地质灾害灾害损失预评估和地质灾害防治工程评价等方面发挥着重要的作用。应用遥感技术开展地质灾害调查评价是极其必要的,它可以贯穿于地质灾害调查评价、监测预警、灾情评估以及灾害防治的全过程,是当代高新技术发展的必然趋势。5·12汶川大地震诱发了大量滑坡、崩塌、泥石流等次生地质灾害,对人民群众的生命财产和社会经济的发展形成了严重威胁。针对次生地质灾害危险性评价,本文选取重灾区汶川县作为研究区域,结合汶川县地质灾害调查与区划项目,探讨了GIS技术与信息量法相结合的评价方法原理及其在汶川县地质灾害风险评估中的具体实施过程,利用三维遥感技术与地理信息技术的空间数据管理和空间数据分析平台,提取次生地质灾害的诱发因子,并对其与次生地质灾害的相关性进行了定量化评述,然后运用信息量模型对次生地质灾害危险性及其空间分布进行预测和定位。主要研究内容如下：(1)主要综述了GIS/RS在区域地质灾害研究中的应用情况和进展,分析了目前GIS/RS的区域地质灾害研究中现状和问题,阐述了三维遥感技术的应用现状和前景,讨论了GIS/RS技术支持下灾区区域地质灾害危险性评价的重点内容和合理的评价模式,为本文研究重点指明了方向,规划了研究的主要内容和期望解决的问题。(2)详细论述了崩滑流地质灾害研究中的关键遥感技术,讨论了数据源的选取、图像的光谱校正、几何校正和正射校正、三维遥感模型的建立,有针对性对地提出了地质灾害不同研究对象、不同研究阶段、不同研究程度的遥感图像处理方法。(3)利用多时相、高分辨率的IKNOS、QtrickBird卫星图像分析了滑坡的形成条件、发育特征、变形破坏迹象以及主要灾情状况。将三维遥感技术应用于汶川县次生地质灾害的信息提取,建立了滑坡区的高精度三维遥感遥感模型。在传统三维图像制作方法基础上,提出了一套实用有效的三维遥感影像制作方法,改善了三维遥感影像的制作效果,提高了三维遥感影像的制作水平,增强了大规模三维遥感影像的实用性。(4)利用ETM+、SPOT5影像相结合,提取了研究区的孕灾条件、崩滑流地质灾害发育现状,评价研究区地质灾害的分布特征。结合崩滑流地质灾害的成因及行为特征修正和完善了地质灾害遥感解译的识别标志和解译方法。(5)基于遥感技术提取地质灾害危险性评价指标的优势,提取次生地质灾害的诱发因子。分析了研究区内次生地质灾害与各影响因子地形地貌、地层岩性、水系、地震断裂之间的相关性特征,并结合信息量法模型进行次生地质灾害危险性评价。高度、中度和轻度危险区的面积分别为1130.196 km2、1739.584 km2、1213.219 km2。本次地震触发次生地质灾害的分布具有集群式分布的特点,即断裂带及其附近地区地质灾害集中发育,而远离断裂带区地质灾害很快衰减,呈零星分布；从灾害发育的区域特征分析,汶川县震后次生地质灾害呈现出北部和东部重、西部和南部轻的特点。所得研究结果与实际情况较吻合.表明地理信息系统结合信息量模型能够快速、有效的对次生地质灾害的空间分布以及危险性作出评价。研究表明,根据已有的滑坡先验知识,以遥感数据、区域地质调查资料作为滑坡因子数据源,结合部分野外调查数据,快速进行大中尺度的区域滑坡危险性评价是可行的。随着空间技术以及计算机技术的快速发展,高分辨率、雷达、高光谱遥感、数字自动测高、遥测数据的使用,能够为区域滑坡研究提供地物类型信息更为丰富的图像。结合地面工程地质、室内实验室测试资料进行中小尺度的地质灾害危险性评价是可行的,遥感技术应用于地质灾害研究需要进一步拓宽。更多还原

【Abstract】 Secondary geological disasters in the earthquake are caused by seismic activity geological disasters. Geological disasters increased earthquake damage effect, increasing the extent of earthquake damage, therefore the risk of secondary geological disasters is an important part of earthquake disaster situation evaluation. It has played an important role in the scope of the geological hazard prediction, geological disaster loss of pre-assessment and evaluation of geological disaster prevention project. Application of remote sensing technology to carry out investigation and assessment of geological hazards is essential, as it can throughout the whole process of investigation and assessment of geological hazards, monitoring and early warning, disaster assessment and disaster prevention, which is the inevitable trend of the development of modern high technology.5·12 Wenchuan earthquake formed a series of secondary landslide, landslides, debris flows, and other mountainous geological disasters. It is a serious threat to peoples’lives and property and socio-economic development. For risk assessment of secondary geological hazards, this paper selected the worst-hit Wenchuan County as the study area, Explores the Combination of GIS technology and methods of evaluation the amount of information theory and its application in risk assessment of geological hazards in Wenchuan County, the specific implementation process, using three-dimensional remote sensing technology and geographical information technology, spatial data management and spatial data analysis platform, extract the secondary geological disaster-induced factors, and its secondary geological disasters with the correlation of the quantitative comments, and then use the amount of information model, the risk of secondary geological disasters and their spatial distribution to predict and positioning. Main research contents are as follows:(1)Chapter one provides a short view of several spatial information technologies applications on landslide field,such as remote sensing,GIS,digital elevation model. Described the application status and prospects of three-dimensional remote sensing technology. Discussed the GIS/RS with the technical support of geological disasters in the reservoir area of regional landslide hazard assessment focused on the evaluation of content and a reasonable model for the focus of this paper pointed out the direction, planning to study the main content and hope to solve the problem.(2) Key remote sensing technique was explained in detailes for collapse, landslide and debris flow geological hazard research. The data sources selection, the spectral image correction, geometric correction and ortho-correction, three-dimensional model establishment of remote sensing were introduced. Remote sensing image processing research methods have raised aim at different research object, different degrees, different research phase of geological hazard.(3) By using IKNOS and QuickBird satellite image multi-temporal, high-resolution to analyse of the formation conditions of landslide, growth characteristics, deformation indications and major disaster situation. Three-dimensional remote sensing technology was applied to extract geological hazards information in the secondary geological disasters and high precision three-dimensional remote sensing model of landslide region was established. A set of practical and effective method of producing three-dimensional remote sensing images was put forward based on the traditional method of three-dimensional image produced, which improve the production effect and level of three-dimensional remote sensing images, enhancing the practicality of large-scale three-dimensional remote sensing images.(4) By using ETM combined with SPOT images of the study to extracted pregnant conditions for disaster, development status collapse, landslide and debris flow geological hazards and evaluation of distribution of geological disasters. Combined with the causes and behavior characteristics of collapse, landslide and debris flow geological hazards to modify and improve the interpretation of geological hazards identification signs and interpretation methods.(5)Induced factors of secondary geological disasters were extracted based on the advantage of remote sensing technique. Analysis of correlative character between secondary geological disasters in the study area and the topography, lithology, hydrology, earthquake rupture, and use information value method to evaluate the risk of secondary geological disasters. The area of high risk, moderate risk and light risk is 1130.196 km2,1739.584km2,1213.219km2 respectively; The distribution of secondary geology disaster triggered by earthquake has the colony type distribution characteristic, namely the fault zone,both sides of water and the nearby regions to focus development of geological disasters, but far away form the fault zone area geology disaster quickly decay and assumes the fragmentary distribution; Analysis from the regional character of disaster devilment shows that risk of secondary geological disaster in north and east area were heavy, west and south were light. The research results inosculate preferably with the fact. So geographical information systems combined with information value model can be quickly and effectively evaluate the spatial distribution and risk of secondary geological disasters.Studies have shown that, according to the existing landslide priori knowledge to remote sensing data, regional geological survey data as a landslide factor data source, with part of the field survey data, large and medium-scale fast regional landslide risk assessment is feasible. As space technology and the rapid development of computer technology, high-resolution, radar, hyperspectral remote sensing, digital automatic altimeter, the use of remote sensing data can be provided for regional landslide research much richer type information features in the image. Combination of ground engineering geology, indoor laboratory test data of small-scale geological hazard assessment is feasible, remote sensing technology in geological hazards research needs further widened.更多还原