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1.
Mahmut G. Drahor Gökhan Göktürkler Meriç A. Berge T. Özgür Kurtulmuş 《Environmental Geology》2006,50(2):147-155
Electrical resistivity imaging is a widely used tool in near surface geophysical surveys for investigation of various geological, environmental and engineering problems including landslide. In this study, an electrical resistivity tomography (ERT) survey was conducted in a landslide area, located in the Söke district of Aydın, Turkey. In 2003, the Neogene-aged units on the slope next to a newly built school building became unstable due to an excavation work and moved after a heavy rainfall. The resulting landslide partly covered the school. The authors carried out a 2-D resistivity survey along three profiles over the landslide mass using a Wenner configuration. It yielded useful information about the geometry and characteristics of the landslide. In addition, a 2-D synthetic resistivity modelling study was carried out to understand the response of the resistivity method to a landslide problem before the field surveys. Eight boreholes were also drilled in the landslide area. Both the drilling and resistivity results indicated the presence of a fault in the site. Also, the resistivity data from the line measured along the axis of the landslide revealed the surface of rupture. 相似文献
2.
Jan Klimeš 《Environmental Earth Sciences》2013,70(2):913-925
Multi-temporal landslide occurrence information acquired through aerial photo interpretation and field mapping was used to assess occurrence frequencies on the slopes around the UNESCO cultural world heritage site of Machu Picchu, Peru. This showed that the coarse time resolution of the historical landslide information may lead to inaccurate interpretations regarding landslide occurrence frequencies in some parts of the study area. In addition, the assumption that the past landslide frequency can be used to describe the future landslide occurrence was not proved in the study area. Thereafter, unique conditional analyses were undertaken to assess landslide susceptibility using a limited number of preparatory factor maps. It showed that large majority of the Inca City is located on least susceptible areas within the region. The results of the susceptibility assessment combined with landslide occurrence frequencies may serve as a basis for the landslide hazard mitigation in the studied area. For these purposes, pixel-based susceptibility maps were generalized into expert-defined landslide management units. These units provide site managers with easily understandable and applicable hence reliable information about future landslide occurrences. An approach describing usage of the resulting susceptibility maps for onsite mitigation purposes was described with respect to the needs of Machu Picchu site managers. 相似文献
3.
Slope movements induced by rainfalls damaging an urban area: the Catanzaro case study (Calabria, southern Italy) 总被引：2，自引：1，他引：1
L. Antronico L. Borrelli R. Coscarelli A. A. Pasqua O. Petrucci G. Gullà 《Landslides》2013,10(6):801-814
Calabria is one of the Italian regions mostly affected by mass movements. The case study of a densely populated neighborhood (Ianò) located in the central-western sector of Calabria is presented. The several landslides triggered in February 2010 caused heavy damages to the built area, infrastructures and productions of this neighborhood, and increased the risk for the inhabitants. The results obtained through field surveys, photo interpretation, analyses of rainfall data and of the urban fabric evolution, historical survey on the reports of the damages caused by landslides, have enabled to formulate hypotheses on the potential causes that triggered landslide events and produced severe consequences on the area. These results have revealed that almost all landslides of February 2010 are partial reactivations of pre-existing landslide deposits. Moreover, the analyses have indicated a critical role of cumulative rainfalls over an interval of 15 days. However, the severe damage framework is explained through an unplanned urbanization which took place across the years on an area characterized by a high level of instability per se. Some buildings have been erected in proximity of or within pre-existing landslide scarps; in other cases, buildings have been constructed even inside the landslide bodies. 相似文献
4.
《Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy》1999,24(10):925-934
Detailed geomorphological mapping carried out in 5 sample areas in the North of Lisbon Region allowed us to collect a set of geological and geomorphological data and to correlate them with the spatial occurrence of landslide. A total of 597 slope movements were identified in a total area of 61.7 km2, which represents about 10 landslides per km2.The main landslide conditioning factors are: lithology and geological structure, slope angle and slope morphology, land use, presence of old landslides, and human activity.The highest landslide density occurs in Cretaceous marls and marly limestones, but the largest movements are in Jurassic clays, marls and limestones.The landslide density is higher on slopes with gradients above 20 °, but the largest unstable area is found on slopes of 10 ° to 15 °, thus reflecting the presence of the biggest slope movements. There is a correlation between landslides and topographical concavities, a fact that can be interpreted as reflecting the significance of the hydrological regime in slope instability.Concerning land use, the highest density of landslides is found on slopes covered with shrub and undergrowth vegetation.About 26% of the total number of landslides are reactivation events. The presence of old landslides is particularly important in the occurrence of translational slides and complex and composite slope movements.20% of the landslide events were conditioned by anthropomorphic activity. Human's intervention manifests itself in ill-consolidated fills, cuts in potentially unstable slopes and, in a few cases, in the changing of river channels.Most slope movements in the study area exhibit a clear climatic signal. The analysis of rainfall distribution in periods of recognised slope instability allows the distinction of three situations: 1) moderate intensity rainfall episodes, responsible for minor slope movements on the bank of rivers and shallow translational slides, particularly in artificial trenches; 2) high intensity rainfall episodes, originating flash floods and most landslides triggered by bank erosion; 3) long-lasting rainfall periods, responsible for the rise of the groundwater table and triggering of landslides with deeper slip surfaces. 相似文献
5.
Kurseong hill subdivision, being one of the three (Kurseong, Sadar and Kalingpong) subdivisions of the hilly portions of the Darjeeling district, West Bengal, India, is affected by severe landslide incidence in the rainy season every year. These landslides and related phenomena frequently create social and economic instability disrupting communication system, claiming property and even sometimes life. Curbing landslide threat, therefore, becomes very much essential over this area. Individual landslide treatments are seen to be taken up by the construction engineers and geo-technical experts almost every year from government level. But reoccurrence of landslides on the same spots or surrounding places clearly reveals that construction works and filling procedures (usually taken up) are not the adequate measures to heal up the problem unless the area is treated as zones of landslides than individual spots of landslide occurrences. Therefore, the assessment of spatial probability of landslide occurrence in various magnitudes in the form of landslide vulnerability zones becomes essential. This spatial probability should also be compared with temporal probability based on the data of landslide incidence of the area for justification of match or mismatch between the inference drawn from the diagnostic criteria based assessment of the possibility level of landslide occurrence and the reality of the landslide scenario in the light of historical perspective of the area. This comparison will finally help to achieve the predicted vulnerability zones of landslide with desirable accuracy to put forward for planning decision. Moreover, such predicted vulnerability zonation can be taken as a standard estimate to use in planning purpose for the areas where historical data of landslide incidences are inadequate or unavailable. With this view in mind, the present paper takes an attempt to verify and compare landslide vulnerability zones derived from Spatial Terrain Parameter Evaluation (STPE) and Anthropogenic Criteria Identification (ACI) methods with the landslide hazard zones prepared from historical data, i.e. landslide inventory of certain length of time. Careful observation reveals that different degrees of landslide vulnerability zones significantly correspond with the similar magnitudes of the landslide hazard zones determined by past occurrence data of landslides over this hill subdivision and therefore validate the predictability procedure of landslide vulnerability zonation. The accuracy performance of the landslide vulnerability zonation model has further been verified by the occurrence dataset of landslide events through receiver operating characteristic curve analysis where area under curve evaluation showed 81.77 % correctness. 相似文献
6.
Landslides are a common phenomenon in parts of Malawi. A number of historical landslides have been documented, and are summarised here. This paper examines the occurrence of landslides in the Rumphi district of northern Malawi, concentrating on the catchment of the Vunguvungu and Banga rivers. This is an area of deeply weathered biotitic gneiss and muscovite schist, with deep, sandy soils, comparatively steep slopes and a rainfall in excess of 1,500 mm per annum. These factors, in association with changing land use patterns, have contributed to the landslide vulnerability of the area. The investigation focuses, as a case study, on the Banga landslide of 1997 for which data are available, and which occurred after unseasonal rain. A unique combination of natural and human induced factors is proposed in explaining the occurrence of landslides. The paper concludes by proposing an elementary vulnerability appraisal procedure for the catchment and by discussing the potential risk of landslides in this area. 相似文献
7.
滑坡位于石太线下行K135路段右侧偏西，平面上呈近似椭圆形，由原有老滑坡复活而形成。根据滑坡勘察，滑坡所处地貌单元属侵蚀剥蚀低中山区，滑坡区地层组成为第四系松散堆积物下伏晚古生代二叠系石千峰组泥岩、砂岩互层。在分析滑坡几何特征、地质构造特征、水文地质条件及滑坡变形破坏特征的基础上，探讨了滑坡的成因，认为老滑坡的成因以自然形成为主，新滑坡则发育并活动于老滑坡堆积物中，因某部门在老滑坡体前缘修建收费站，进行了大面积不适当的工程开挖，形成临空面，加之降雨的作用降低了土体的粘聚力及抗剪强度，在上覆岩土体的重力作用下形成新滑坡。老滑坡为巨型厚层滑坡，属于自然滑坡，新滑坡为大型中层滑坡，属于工程滑坡。 相似文献
8.
2017年6月24日,四川省茂县叠溪镇新磨村发生高位顺层山体滑坡,滑动高差达1 160 m,滑动平距约2 200 m。该滑坡的滑动方量巨大,与其滑动过程中产生的铲刮效应有关。为分析其铲刮效应,文章通过现场调查、遥感影像解译和无人机航拍图像,确定该滑坡的滑动全过程为:多次历史地震造成滑坡源区岩体结构破碎,降雨沿顶部裂隙入渗导致水压力增大及石英砂岩中的薄层板岩软化,在长期疲劳效应下斜坡上部岩体最终发生滑动;上部滑体在运移过程中,对斜坡中部浅表风化层、部分基岩及下部老滑坡堆积体进行铲刮并重新堆积。采用Rockfall软件模拟源区滑体的运动路径、速度与能量,结果表明:在碎屑流区和老滑坡堆积区都存在明显的集中铲刮作用,整个滑坡的高危险区也主要位于该区域,所以危险性分区可代表不同滑坡区域的铲刮程度。计算得两个区域的铲刮方量分别为4.9×106,4.38×106 m3,滑坡总方量为13.35×106 m3。该模拟和计算方法迅速有效,可为以后类似滑坡的应急、救灾和铲刮方量计算提供参考。 相似文献
9.
巴中市地处四川盆地和秦岭造山带的过渡地带,地质构造以宽缓的隔档式褶皱为主,地层岩性主要为砂泥岩互层的红层岩体,红层滑坡灾害多为强降雨诱发。开展滑坡灾害与降雨雨型关系的研究,可为该地区滑坡灾害临界降雨阈值和预警服务提供参考。文章通过统计巴中市强降雨事件与滑坡发生的对应关系,初步揭示了滑坡灾害触发的降雨特征,并在分析降雨强度的基础上,结合降雨历时和降雨过程,对巴中市2007—2016年之间23场月降雨量大于200 mm的降雨事件进行了细分,共划分为单峰型、前峰型、后峰型、递增型、递减型、均匀型6类降雨雨型。对各类降雨雨型下滑坡发生数量进行统计,递增型和单峰型降雨事件下滑坡发生的比例分别为46.90%和25.02%。经稳定性计算分析,递增型和单峰型两类雨型条件下滑坡稳定性有明显降低,降雨过程对滑坡发生具有显著影响。结果表明:强降雨期间应加强降雨雨型的分析,为适时发布区域滑坡灾害预警信息、做好提前避让提供技术支撑。 相似文献
10.
Large old landslides are common in the Three Gorges area. Baota landslide, a large rockslide, is one of the largest landslides
in the Three Gorges area. In the landslide body there are two terraces to be recognized. The two terrace deposits is not a
two-grade terrace, but mainly remnants left by an occurrence of Baota landslide. Optically stimulated luminescence (OSL) dating
suggests that the age of the terrace deposits is 38–32 kyr BP. The OSL ages along with other Thermoluminescence (TL) and Radiocarbon
(14C) ages support the conclusion that the Baota landslide was originally triggered by strong precipitation occurred in a warm
climate period of 30,000–40,000 years BP. 相似文献
11.
建立高效合理的区域滑坡灾害降雨预警模型对滑坡防治具有重要意义.然而以往的研究多侧重于临滑预警,对蠕变型滑坡在强降雨工况下的短暂加速变形的预警研究还有待深入.以三峡库区云阳县域内滑坡为例,首先根据滑坡地表位移监测数据的特点对统计样本进行合理筛选.再通过降雨因子与滑坡发生的相关性分析以及对滑坡在降雨条件下位移变化情况的数值模拟,确定了适用于不同时间阶段的降雨统计变量.然后将考虑了滑坡规模特征的滑坡位移比（累计位移与滑坡纵长之比）作为变形指标,分时段统计滑坡地表位移监测数据与历史降雨信息,建立了日降雨数据与月位移数据的对应关系,得到了可用于确定降雨量阈值的位移比模型,并获得了云阳县蠕变型滑坡的五级预警分区.最后分别选用研究区滑坡险情实例、长年位移监测数据及极端降雨事件对模型预警效果进行检验.结果显示基于专业监测数据的位移比模型的滑坡降雨预警结果与实际情况相符,可为蠕变型滑坡的预警预报提供依据. 相似文献
12.
Almost the entire Italian territory is prone to hydrogeological risk mostly due to landslides and flooding. The high frequency of extreme weather events in areas prone to geological–hydraulic hazards contributes significantly to increasing the risk for cities and its infrastructure, but above all for the people living there. Therefore, it is vital to research into rapid monitoring techniques to be applied following a disaster such as a landslide, so that important background information, useful for planning interventions aimed at hazard mitigation, can be obtained. This work seeks to identify the depth of the sliding surface of a landslide affecting the municipal area of Tripi (village in the Messina province, Sicily), through two geophysical field surveys (MASW and HVSR) undertaken in the same area at an interval of about 5 years. The MASW surveys have enabled to reconstruct the distribution of shear wave velocity with depth. The HVSR surveys have provided information on resonant frequency and directional effects. The data integration obtained by the two methods allowed to reconstruct impedance contrast sections indicating the depth of the sliding surface of the landslide.
相似文献13.
Almost the entire Italian territory is prone to hydrogeological risk mostly due to landslides and flooding. The high frequency of extreme weather events in areas prone to geological–hydraulic hazards contributes significantly to increasing the risk for cities and its infrastructure, but above all for the people living there. Therefore, it is vital to research into rapid monitoring techniques to be applied following a disaster such as a landslide, so that important background information, useful for planning interventions aimed at hazard mitigation, can be obtained. This work seeks to identify the depth of the sliding surface of a landslide affecting the municipal area of Tripi (village in the Messina province, Sicily), through two geophysical field surveys (MASW and HVSR) undertaken in the same area at an interval of about 5 years. The MASW surveys have enabled to reconstruct the distribution of shear wave velocity with depth. The HVSR surveys have provided information on resonant frequency and directional effects. The data integration obtained by the two methods allowed to reconstruct impedance contrast sections indicating the depth of the sliding surface of the landslide. 相似文献
14.
Landslide susceptibility zonation method based on C5.0 decision tree and K-means cluster algorithms to improve the efficiency of risk management 总被引：1，自引：0，他引：1
Machine learning algorithms are an important measure with which to perform landslide susceptibility assessments,but most studies use GIS-based classification methods to conduct susceptibility zonation.This study presents a machine learning approach based on the C5.0 decision tree(DT)model and the K-means cluster algorithm to produce a regional landslide susceptibility map.Yanchang County,a typical landslide-prone area located in northwestern China,was taken as the area of interest to introduce the proposed application procedure.A landslide inventory containing 82 landslides was prepared and subse-quently randomly partitioned into two subsets:training data(70％landslide pixels)and validation data(30％landslide pixels).Fourteen landslide influencing factors were considered in the input dataset and were used to calculate the landslide occurrence probability based on the C5.0 decision tree model.Susceptibility zonation was implemented according to the cut-off values calculated by the K-means clus-ter algorithm.The validation results of the model performance analysis showed that the AUC(area under the receiver operating characteristic(ROC)curve)of the proposed model was the highest,reaching 0.88,compared with traditional models(support vector machine(SVM)=0.85,Bayesian network(BN)=0.81,frequency ratio(FR)=0.75,weight of evidence(WOE)=0.76).The landslide frequency ratio and fre-quency density of the high susceptibility zones were 6.76/km2 and 0.88/km2,respectively,which were much higher than those of the low susceptibility zones.The top 20％interval of landslide occurrence probability contained 89％of the historical landslides but only accounted for 10.3％of the total area.Our results indicate that the distribution of high susceptibility zones was more focused without contain-ing more"stable"pixels.Therefore,the obtained susceptibility map is suitable for application to landslide risk management practices. 相似文献
15.
滑坡形态要素及发育特征研究是古(老)滑坡野外调查和遥感影像识别以及复杂艰险山区基础设施选线(址)工程地质研究的重要内容。青藏高原东缘地质环境条件复杂,在内外动力地质作用下该区域发育有大量古(老)滑坡体。本文以位于青藏高原东缘毛垭坝盆地的大型老滑坡——乱石包滑坡为例,以滑坡塘形态要素为研究对象,综合利用无人机摄影测量技术、水文地质调查、自然电位地球物理勘探以及渗流数值模拟等研究方法,探明了乱石包滑坡塘形态要素几何特征和渗流发育特征并揭示了其成因和演化机制。研究结果表明乱石包滑坡发生后在滑坡后缘平台和主滑壁处形成低洼地形,地下水沿该处发育的理塘—德巫断裂产生泉水出露,地下水持续补给最终形成体积约为5505 m3的大型滑坡塘,最大水深位于滑坡塘西侧,深度约为2 m。滑坡运动过程中在滑坡后缘平台下部形成次级滑壁,在上部滑坡塘高水头长期作用下,物质结构松散破碎的滑坡后缘平台西侧坡体内形成内部渗流并在陡峭的次级滑壁中部产生泉水出露,进而在下部滑坡洼地处形成体积约为35 m3的小型滑坡塘。长期渗流作用下,堆积体内部存在渗流潜蚀风险,建议后期针对次级滑壁上泉水出露点的渗流潜蚀速率开展长期观测研究,为乱石包滑坡塘演化研究提供重要依据。 相似文献
16.
Landslide susceptibility assessment in the İzmir (West Anatolia,Turkey) city center and its near vicinity by the logistic regression method 总被引：1，自引：1，他引：0
A landslide susceptibility assessment for İzmir city (Western Turkey), which is the third biggest city of Turkey, was performed
by a logistic regression method. A database of landslide characteristics was prepared using detailed field surveys. The major
landslides in the study area are generally observed in the field, dominated by weathered volcanics, and 39.63% of the total
landslide area is in this unit. The parameters of lithology, slope gradient, slope aspect, distance to drainage, distance
to roads and distance to fault lines were used as variables in the logistic regression analysis. The effect of each parameter
on landslide occurrence was assessed from the corresponding coefficients that appear in the logistic regression function.
On the basis of the obtained coefficients, lithology plays the most important role in determining landslide occurrence and
distribution. Slope gradient has a more significant effect than the other geomorphological parameters, such as slope aspect
and distance to drainage. Using a predicted map of probability, the study area was classified into five categories of landslide
susceptibility: very low, low, moderate, high and very high. Whereas 49.65% of the total study area has very low susceptibility,
very high susceptibility zones make up 11.69% of the area. 相似文献
17.
针对叶城柯克亚乡波龙7.20突发泥石流灾害,现场开展了应急科学调查。对沟下游泥石流堆积区进行量测,对上游突发小型滑坡-堰塞湖-泄流全过程开展实时观察。结果发现:泥石流固体物质主要是晚更新世风积土滑坡和中元古变质岩及碳酸盐岩崩塌,水体来源主要是强降雨导致的上游洪水及堰塞湖溃决;沟谷上游以稀性泥石流为主,下游加入了崩塌块体及河道砂砾石,粘度有所增大;堆积区呈块石散落和淤积状态。据现场多个老堰塞坝推测,波龙沟泥石流发生周期约15~20年。现有停车场位于沟口堆积区,需加大极端洪水及泥石流排泄空间,拓宽排导沟槽净空。 相似文献
18.
受拟建马边河舟坝水库蓄水影响,库区部分老场镇将被淹没,前期资料表明,目前规划的某新场址位于一古滑坡体上,因此该滑坡的稳定性对拟建场址移民居住的适宜性有决定性的作用。通过阐述该滑坡的地质条件及成因机制、变形破坏特征,对滑坡进行了定性分析和定量综合评价。结果表明,该古滑坡体在现状及蓄水后均处于整体稳定状态,但局部受场址的开发性影响可能存在局部失稳,建议采取一定防护措施,以满足移民新场址要求。 相似文献
19.
随着中国经济高速发展和加强对基本农田的保护,越来越多的大型火电厂建设于山区且多数为坑口电厂,一般会涉及到西南地区主要含煤地层二叠系上统龙潭组（P2l）。龙潭组是由海陆交替相含煤砂、页岩等软质、易滑地层构成的,在龙潭组岩层区建设坑口电厂大型山体滑坡等不良地质作用是不可回避的工程地质问题。本文以贵州省某电厂大型山体滑坡对工程场地适宜区域划定的影响研究为出发点,认为山区坑口电厂建设中对大型山体滑坡的分析评价只要遵守查明基本地质条件,评价滑坡稳定性,划定适宜建设区域,提出处理建议的基本工作流程,大型火力电厂在大型山体滑坡附近建设是可行的。 相似文献
20.
Gökhan Demir Mustafa Aytekin Aykut Akgün Sabriye Banu İkizler Orhan Tatar 《Natural Hazards》2013,65(3):1481-1506
The North Anatolian Fault is known as one of the most active and destructive fault zones which produced many earthquakes with high magnitudes both in historical and instrumental periods. Along this fault zone, the morphology and the lithological features are prone to landslides. Kuzulu landslide, which is located near the North Anatolian Fault Zone, was triggered by snow melting without any precursor, occurred on March 17, 2005. The landslide resulted in 15 deaths and the destruction of about 30 houses at Kuzulu village. There is still a great danger of further landslides in the region. Therefore, it is vitally important to present its environmental impacts and prepare a landslide susceptibility map of the region. In this study, we used likelihood-frequency ratio model and analytical hierarchy process (AHP) to produce landslide susceptibility maps. For this purpose, a detailed landslide inventory map was prepared and the factors chosen that influence landslide occurrence were: lithology, slope gradient, slope aspect, topographical elevation, distance to stream, distance to roads, distance to faults, drainage density and fault density. The ArcGIS package was used to evaluate and analyze all the collected data. At the end of the susceptibility assessment, the area was divided into five susceptibility regions, such as very low, low, moderate, high and very high. The results of the analyses were then verified using the landslide location data and compared with the probability model. For this purpose, an area under curvature (AUC) and the seed cell area index assessments were applied. An AUC value for the likelihood-frequency ratio-based model 0.78 was obtained, whereas the AUC value for the AHP-based model was 0.64. The landslide susceptibility map will help decision makers in site selection and the site-planning process. The map may also be accepted as a basis for landslide risk-management studies to be applied in the study area. 相似文献