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基于改进频率比法的川藏铁路沿线及邻区地质灾害易发性分区评价 总被引：2，自引：0，他引：2
川藏铁路是我国目前正在规划建设的重要铁路干线之一,地处地形和地质条件极为复杂的青藏高原东部,复杂的地质背景与脆弱的地质环境造成川藏铁路沿线及邻区地质灾害极为发育,严重威胁着川藏铁路的规划建设。在对地质灾害易发性评价方法分析的基础上,首先对传统的地质灾害易发性评价频率比方法进行改进,克服了传统通用方法中频率比值分布的不连续性,提高了各地质灾害影响因子敏感性的区分度,并减小了因子分级的主观性。利用ROC曲线与空间熵的定量对比验证表明,改进频率比法的地质灾害易发性评价模型优于传统方法。根据地质灾害的发育分布特征,选取地面高程、地形坡度、地形坡向、地形曲率、地形起伏度、工程地质岩组、地震动峰值加速度、断裂密度、水系距离、道路距离、降水量与植被指数等影响地质灾害的主要因素,结合地质灾害调查数据,首先分析各影响因子的地质灾害敏感性,并进一步对川藏铁路沿线及邻区的地质灾害易发性进行评价和分区。评价结果表明,研究区地质灾害的发育分布主要受控于断裂、水系和道路等线状要素,以及地形坡度和地形起伏度等地形地貌因素,并且断裂密度和地形起伏度相较其他因子具有更大的地质灾害敏感性区分度。地质灾害极高易发区和高易发区主要分布于大型水系两岸、道路两侧的高山河谷沿线的狭窄地带,使沿河谷与已有道路规划展布的川藏铁路面临着严重的地质灾害威胁,铁路规划建设部门应加强该地带的地质灾害排查、防治和线路优化工作。 相似文献
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鲜水河断裂带是发育于青藏高原东缘的一条大型左旋走滑断裂带,该区新构造活动强烈且历史强震频发,一系列大型-巨型滑坡沿断裂带密集分布。在资料收集的基础上,对鲜水河断裂带两侧10 km区域内进行遥感解译和野外地质调查,建立数据库并对滑坡主要影响因素进行分析。在滑坡区域发育分布规律分析的基础上,选取地形坡度、地形坡向、地面高程、平面曲率、地形湿度指数、活动断裂、工程地质岩组、年降雨量、河流、道路、植被覆盖指数等11个因素作为滑坡易发性评价因子,在ArcGIS软件平台上,采用证据权模型开展了滑坡易发性评价。根据成功率曲线对评价结果的检验,滑坡易发性评价结果具有较好的精度,并将研究区的滑坡易发程度划分为极高易发、高易发、中等易发、低易发和不易发5个级别。滑坡的易发性受鲜水河断裂带影响显著,极高易发区和高易发区主要分布在东谷到道孚县沿鲜水河断裂带两侧,以及康定县城和磨西镇附近;中等易发区主要分布在鲜水河支流两岸及省道沿线;滑坡低易发区和不易发区主要分布在人类工程活动少的高山地带以及地形相对平缓的区域。滑坡易发性评价结果很好地反映了鲜水河断裂带区域内滑坡发育分布现状,为该区重大工程规划建设和防灾减灾提供参考依据。 相似文献
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基于斜坡单元与信息量法结合的宝塔区黄土滑坡易发性评价 总被引：4，自引：0，他引：4
滑坡易发性评价对滑坡灾害的防治与管理具有重要意义。为了评价延安宝塔区黄土滑坡易发性,以斜坡为基本评价单元,选取斜坡坡度、坡高、坡向、坡形、斜坡结构类型、植被和人类工程活动7个指标作为评价因子,在Arc GIS平台下,利用信息量模型对研究区的黄土滑坡进行易发性分区评价。评价结果表明,宝塔区滑坡高易发区面积1092.39km~2,占全区面积的30.81%,主要分布于宝塔区的中部及北部地区,低易发区集中于宝塔区南部汾川河流域。以斜坡作为评价单元提高了与实际地形地貌的吻合度。应用信息量模型进行滑坡易发性评价具有较高的预测精度,已有滑坡点落在很高易发区和高易发区中的比例为95.7%,较真实地反映了客观实际。 相似文献
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为探讨不同滑坡易发性评价模型其评价结果的差异和评价精度,本文以贵州省桐梓县为研究区,选取坡度、斜坡结构、地形起伏度、工程地质岩组、距水系距离、距断层距离6个影响因子建立评价指标体系,分别采用信息量模型、确定性系数法、频率比法3种方法开展区域地质灾害易发性评价,并通过ROC曲线对评价结果进行精度验证。评价结果表明:信息量模型(AUC=0800)的评价精度优于确定性系数法(AUC=0784)和频率比法(AUC=0787),因此信息量模型更适合于该区域的滑坡易发性评价。 相似文献
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以斜坡地质灾害(滑坡、崩塌)高发的金川县为例,采用遥感解译与地面调查相结合的综合手段获取灾害数据.选取地形起伏度、坡度、斜坡坡形、斜坡结构类型、工程地质岩组、地质构造、水系、植被与土地利用类型等8个影响因素作为评价因子,分别基于区内斜坡地质灾害点和斜坡地质灾害面积采用信息量模型开展易发性评价.利用最新提出的历史地质灾害... 相似文献
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本文以地质灾害多发的新疆玛纳斯河流域作为研究区,在剖析了信息量模型、逻辑回归模型在地质灾害易发性评价中各自的优势与局限性的基础上,探索了信息量-逻辑回归耦合模型的科学性与优势;基于该区域地质环境与最新地质灾害数据,选取地形起伏度、坡度、坡向、土地利用类型、地层岩性、地形湿度指数(TWI)、河流、断层、高程9个影响因素作为评价因子,以全区355处地质灾害点为样本数据,在进行评价因子分析的基础上,通过ArcGIS平台对玛纳斯河流域进行了地质灾害易发性评价。评价结果表明,地质灾害高易发区主要分布于流域南部中低山丘陵地区,高易发区与较高易发区的面积分别为1760 km2、2200 km2,占研究区总面积7.98%、9.97%。经检验评价精度高达91.3%,该研究可为当地地质灾害防治与国土空间规划提供重要参考。 相似文献
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川藏交通廊道典型高位滑坡地质力学模式 总被引：7，自引：0，他引：7
川藏交通廊道穿越青藏高原东缘高山峡谷区,大型—巨型高位滑坡多发频发,是铁路、高速公路等交通设施规划建设必须考虑的重要因素。在区域成灾地质背景分析和现场调查的基础上,以地貌特征、斜坡岩体结构、促发条件等为基本要素,总结归纳了川藏交通廊道典型高位滑坡的6类地质力学模式,包括:堆积体滑移型、顺层滑移拉裂型、卸荷剪断型、岩溶贯通拉裂型、崩滑溃散型和构造控制型等。结合典型高位滑坡案例,重点剖析了各类滑坡启动的简化力学机制,并给出了相应的成因解析。综合考虑不同类型高位滑坡的控制因素和易发性分区结果,初步圈定了川藏铁路雅安—林芝段高位滑坡易发靶区,对高位滑坡隐患早期识别、重大工程选址选线和防灾减灾具有重要的指导作用。 相似文献
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开展铁路沿线滑坡易发性评价对川藏交通廊道工程建设及运维过程中的风险管理具有重要意义.提出一种层数自适应、通道加权的卷积神经网络(layer adaptive weighted convolutional neural network,LAW-CNN),对川藏交通廊道沿线滑坡易发性进行评价.依据野外调查和影响因素分析筛选出影响滑坡发生的影响因子,绘制滑坡编目,构造用于易发性评价的实验数据集;针对卷积神经网络的权重初值、网络层数等超参数难以优化设置的问题,提出基于影响因子信息熵的通道加权方法和网络层数优选策略,通过多通道加权和层数自适应分类卷积的方式提出滑坡易发性制图的LAW-CNN架构;搜索最优LAW-CNN网络结构并训练网络参数,获取研究区滑坡发生概率并进行易发性分级评价.所提的LAW-CNN模型可以不同权重和不同深度挖掘影响因子的深层特征,实验结果表明,模型曲线下面积(area under curve,AUC)值为0.852 8,极高易发区滑坡点密度为1.251 9,均优于SVM(support vector machine)和CNN模型;川藏交通廊道沿线滑坡极高和高易发区主要集中在大江大河两侧以及横断山区.LAW-CNN模型可较好评价川藏交通廊道滑坡易发性,能够为川藏交通廊道的建设和灾害防治提供科学的依据. 相似文献
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西秦岭北缘断裂沿"一带一路"交通廊道展布,是南北活动构造带强震丛集发育的节点之一,地震地质灾害风险极高。基于地质调查、测绘与数值分析,查明了断裂在天水地区触发的地震滑坡分布特征,探讨了断裂触发滑坡的形成机制。研究表明:(1)西秦岭北缘活动触发的巨、大型滑坡为断裂地貌过程的一部分,易在断裂的阶区聚集发育,其枢纽部位也有零星的分布;(2)巨大型滑坡集中于历史极震区内,断裂破裂过程中的近场惯性滑移、远场地震动是主要触发因素,二者耦合作用导致巨大型滑坡在断裂带两侧具有对称分布特征,活动强度由近及远而逐渐变弱;(3)断裂水平滑移、破裂引起的斜坡滑动变形以结构面贯通为主要表现形式,具有强烈的方向效应、近直立断层的区域地震动效应及地震波的山体地形放大效应,这些力学效应在滑坡破坏过程产生断裂结构面、次级羽裂结构面与滑动面,它们协同控制了滑坡的运动;(4)极端降雨触发的泥流是巨大型滑坡堆积体复活运动的主要形式,是现今防灾减灾重点。 相似文献
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Landslide susceptibility mapping using Bayesian approach in the Sultan Mountains (Akşehir,Turkey) 总被引：1，自引：0，他引：1
Adnan Ozdemir 《Natural Hazards》2011,59(3):1573-1607
Landslides cause heavy damage to property and infrastructure, in addition to being responsible for the loss of human lives
in many parts of the Turkey. The paper presents GIS-based spatial data analysis for landslide susceptibility mapping in the
regions of the Sultan Mountains, West of Akşehir, and central part of Turkey. Landslides occur frequently in the area and
seriously affect local living conditions. Therefore, spatial analysis of landslide susceptibility in the Sultan Mountains
is important. The relationships between landslide distributions with the 19 landslide affecting parameters were analysed using
a Bayesian model. In the study area, 90 landslides were observed. The landslides were randomly subdivided into 80 training
landslides and 10 test landslides. A landslide susceptibility map was produced by using the training landslides. The test
landslides were used in the accuracy control of the produced landslide susceptibility map. Approximately 9% of the study area
was classified as high susceptibility zone. Medium, low and very low susceptibility zones covered 8, 23 and 60% of the study
area, respectively. Most of the locations of the observed landslides actually fall into moderate (17.78%) and high (77.78.
%) susceptibility zones of the produced landslide susceptibility map. This validates the applicability of proposed methods,
approaches and the classification scheme. The high susceptibility zone is along both sides of the Akşehir Fault and at the
north-eastern slope of the Sultan Mountains. It was determined that the surface area of the Harlak and Deresenek formations,
which have attained lithological characteristics of clayey limestone with a broken and separated base, and where area landslides
occur, possesses an elevation of 1,100–1,600 m, a slope gradient of 25°–35° and a slope aspect of 22.5°–157.5° facing slopes. 相似文献
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Turkey confronts loss of life and large economic losses due to natural disasters caused by its morphologic structure, geographical placement, and climate characteristics. The Kuzulu (Koyulhisar) landslide, which caused loss of life and property on 17th March 2005, occurred in an area near the country’s most important active fault, the North Anatolian Fault Zone. To mitigate and prevent landslide damages, prediction of landslide susceptibility areas based on probabilistic methods has a great importance. The purpose of this study was to produce a landslide susceptibility map by the logistic regression and frequency ratio methodologies for a 733-km2 area near the North Anatolian Fault Zone from the southeast of Niksar to Resadiye in Tokat province. Conditioning parameters, such as elevation, slope gradient, slope aspect, distance to streams, roads, and faults, drainage density, and fault density, were used in the analysis. Before susceptibility analysis, the landslides observed in the area were separated into two groups for use in analysis and verification, respectively. The susceptibility maps produced had five different susceptibility classes such as very low, low, moderate, high, and very high. To test the performance of the susceptibility maps, area under curve (AUC) approach was used. For the logistic regression method, the AUC value was 0.708; while for the frequency rate method, this value was 0.744. According to these AUC values, it could be concluded that the two landslide susceptibility maps obtained were successful. 相似文献
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全新世以来青藏高原东部巴塘断裂带活动强烈,地形地貌和地质构造复杂,历史地震频发,并诱发大量滑坡灾害。基于巴塘断裂带地震滑坡长期防控的需要,在分析区域地质灾害成灾背景和发育分布特征的基础上,采用Newmark模型完成了巴塘断裂带50年超越概率10%的潜在地震滑坡危险性预测评价,并完成地震滑坡危险性区划。结果表明:巴塘断裂带及其临近的金沙江断裂带区域、金沙江及其支流沿岸具有较高的潜在地震滑坡危险性,地震滑坡危险区具有沿断裂带和大江大河等峡谷区分布的总体趋势,受活动断裂和地形地貌影响显著;距离断层越近、坡度越大的斜坡,地震滑坡危险性越高;规划建设中的川藏铁路经巴塘县德达乡、白玉县沙马乡,向西北延伸,跨越金沙江,可以穿越较少的地震滑坡危险区,金沙江水电工程规划建设需加强潜在地震滑坡危害研判及防控。巴塘断裂带潜在地震滑坡危险性评价结果可为区域城镇开发和重大工程规划建设的地震滑坡长期防控提供科学参考。 相似文献
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Landslide zoning in a part of the Garhwal Himalayas 总被引：21，自引：1，他引：20
The Himalayas are undergoing constant rupturing in the thrust belt zone in the Garhwal Himalayas, due to which earthquake
and mass movement activity is triggered. These processes of mass movement and landslides have been constantly modifying the
landscape. Landslides are one of the indicators of the geomorphological modifications taking place in this active and fragile
terrain. This work is aimed at providing another example of landslide susceptibility mapping based on geological and geomorphological
attributes. The data collected from aerial photographs, topographic sheets and the image suggests that there is a correlation
between the distribution of landslides and some of the geological and geomorphological factors, for example, the distance
from an active fault, relative relief and slope. Parameters like factor of safety, altitude, relief, slope and the distance
from the fault lineament have been included in the study. A rating system has been applied to the factors for arriving at
a quantitative estimate of landslide susceptibility for each physiographic unit. Since terrain classification forms the foundation
of this work, the entire study can be grouped into two sequential activities: (1) the terrain classification and (2) landslide
susceptibility mapping. The result is the landslide susceptibility zoning map presented. The landslides have not been classified
with respect to time and may represent the final result of the on-going geological, geomorphological and seismic activity
since the Holocene period or late Pleistocene time when the glaciers retreated.
The area chosen for the study lies between Badri gad and Barni gad in Yamuna valley region of the Garhwal Himalaya where a
very large scale investment is in the pipe line for Hydroelectric power generation.
Received: 12 August 1993 · Accepted: 13 January 1998 相似文献
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Prabin Kayastha 《Arabian Journal of Geosciences》2015,8(10):8601-8613
For assessing landslide susceptibility, the spatial distribution of landslides in the field is essential. The landslide inventory map is prepared on the basis of historical information of individual landslide events from different sources such as previously published reports, satellite imageries, aerial photographs and interview with local inhabitants. Then, the distribution of landslides in the study area is verified with field surveys. However, the selection of contributing factors for modelling landslide susceptibility is an inhibit task. The previous studies show that the factors are chosen as per availability of data. This paper documents the landslide susceptibility mapping in the Garuwa sub-basin, East Nepal using frequency ratio method. Nine different contributing factors are considered: slope aspect, slope angle, slope shape, relative relief, geology, distance from faults, land use, distance from drainage and annual rainfall. To analyse the effect of contributing factors, the landslide susceptibility index maps are generated four times using (a) topographical factors and geological factors, (b) topographical factors, geological factors and land use, (c) topographical factors, geological factors, land use and drainage and (d) all nine causative factors. By comparing with the pre-existing landslides, the fourth case (considering all nine causative factors) yields the best success rate accuracy, i.e. 81.19 %, which is then used to produce the final landslide susceptibility zonation map. Then, the final landslide susceptibility map is validated through chi-square test. The standard chi-square value with 3 degrees of freedom at the 0.001 significance level is 16.3, whereas the calculated chi-square value is 7,125.79. Since the calculated chi-square value is greater than the standard chi-square value, it can be concluded that the landslide susceptibility map is considered as statistically significant. Moreover, the results show that the predicted susceptibility levels are found to be in good agreement with the past landslide occurrences. 相似文献
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巴塘断裂带位于青藏高原东部,呈北东—南西向展布,全新世活动强烈,沿断裂带崩塌、滑坡、泥石流等地质灾害极为发育。基于遥感解译和野外地质调查,在巴塘断裂带两侧10 km范围内识别出滑坡93处;在分析滑坡空间发育特征的基础上,选取地形地貌(地面高程、地形坡度和地形坡向)、地形湿度指数、地层岩性、活动断裂、降雨量、水系、人类工程活动和植被覆盖等10个因素作为滑坡易发程度的主控因素,采用加权证据权法建立滑坡易发性评价模型,开展巴塘断裂带滑坡易发性评价;成功率(ROC)曲线检验结果表明此次滑坡易发性评价的准确率为82.3%。采用基于自然断点法将滑坡易发程度划分为极高易发、高易发、中等易发和低易发4个级别,结果表明滑坡易发性受巴塘断裂带和河流控制显著,极高易发区和高易发区主要分布在巴塘断裂带、金沙江和巴曲河谷及一级支流两侧,中等易发区主要分布在巴曲各支流中上游,低易发区主要分布在人类工程活动弱的高山地带以及地形相对平缓的区域。滑坡易发性评价结果很好地反映了巴塘断裂带现今滑坡发育分布特征,对该区重大工程规划建设和防灾减灾具有科学指导意义。 相似文献