共查询到10条相似文献，搜索用时 109 毫秒
1.
自2008年5月12日汶川MW7.9地震发生以来,针对地震滑坡与光学遥感影像的特点,制定了地震滑坡编录新原则、遥感影像选取新原则及地震滑坡属性库建立原则。文中介绍了21世纪初4次大地震事件触发滑坡基础数据建设成果:包括2008年5月12日汶川MW7.9地震,此次地震触发了至少197 481处滑坡;2010年4月14日玉树MW6.9地震至少触发2 036处滑坡;2010年1月12日海地MW7.0地震至少触发30 828处滑坡;2007年4月21日智利艾森峡湾MW6.2地震至少触发1 000处滑坡。分析了地震触发滑坡基础数据建设成果与以往研究的不同。最后从地震滑坡基础数据建设成果对地震滑坡分布规律与危险性评价的影响,对震区滑坡与泥石流防灾减灾的意义,对地震震级、活动断层运动习性、地震烈度等的反馈,对震区河流与地貌演化研究的基础意义,对全球地震震级与触发滑坡关系研究的意义等几个方面,分析了地震滑坡基础数据建设的实际应用价值与科学研究意义。 相似文献
2.
3.
《地震研究进展（英文）》2023,3(1):100181
This study constructs a preliminary inventory of landslides triggered by the MS 6.8 Luding earthquake based on field investigation and human-computer interaction visual interpretation on optical satellite images. The results show that this earthquake triggered at least 5 007 landslides, with a total landslide area of 17.36 ?km2, of which the smallest landslide area is 65 ?m2 and the largest landslide area reaches 120 747 ?m2, with an average landslide area of about 3 500 ?m2. The obtained landslides are concentrated in the IX intensity zone and the northeast side of the seismogenic fault, and the area density and point density of landslides are 13.8%, and 35.73 ?km?2 peaks with 2 ?km as the search radius. It should be noted that the number of landslides obtained in this paper will be lower than the actual situation because some areas are covered by clouds and there are no available post-earthquake remote sensing images. Based on the available post-earthquake remote sensing images, the number of landslides triggered by this earthquake is roughly estimated to be up to 10 000. This study can be used to support further research on the distribution pattern and risk evaluation of the coseismic landslides in the region, and the prevention and control of landslide hazards in the seismic area. 相似文献
4.
长期、缓慢的地貌演化具有阶段性的特点,构造抬升与侵蚀相互作用引起山坡物质运移,使地貌单元具有向相对稳定状态转变的趋势。滑坡作为山坡物质运移的一种主要方式,在地貌演化过程中起到了重要作用。2014年鲁甸MS6.5地震诱发了异常多的滑坡,可以看作是该区地貌物质在短时间内发生的集中调整过程。这些滑坡主要沿河流分布,表明河流侵蚀使河岸地形变陡、强度降低,形成发生物质运移的有利条件,从而增强了地震滑坡的易发性。文中以SRTM 30m数字高程模型(DEM)为基础,通过对鲁甸地震滑坡分布区的网格化划分,对研究区滑坡分布及其与地形特征的关系进行了定量分析。除计算网格单元内的高程、高差及算数平均坡度外,还提出期望坡度的计算方法以对网格单元内的地形进行平滑。在此基础上,对该区域地貌特征参数自相关性进行了分析和比较,以判断地表物质分布是否均衡并寻找其中的分异性单元(滑坡易发区)。结果表明,研究区的高程与坡度、地形高差呈负相关,反映出显著的河流侵蚀效应;其中地形特征在分析单元的期望坡度与算数平均坡度这2个不同尺度下表现出很高的一致性,可能代表着研究区地貌在演化中具有的一种动态稳定特征,而与此特征不符的地貌单元则是可能发生滑坡进行物质调整的区域,是地貌自适应调整的一种表现。2014年鲁甸地震触发的大部分规模较大的滑坡发生在期望坡度与平均坡度差异较大的区域,这些区域大多位于河谷,显示河流侵蚀及其所造成的地形特征对滑坡易发性的控制作用。基于这样的认识,认为该区未来的物质运移区域仍然受到河流侵蚀的控制,滑坡易发性高的位置仍将沿河流分布。作为对比的九寨沟地震震区的地貌参数分析结果则表现出不同的特点,这种地形地貌分布上的差异性与滑坡空间分布及滑坡规模等之间的关系值得深入探讨。 相似文献
5.
GIS支持下的地震诱发滑坡危险区预测研究 总被引：24，自引：0，他引：24
为了满足对地震诱发滑坡危险区预测的不断增长的迫切要求，灾害评价成为帮助决策过程重要的基础工具之一。即使地震滑坡危险性各组份的评价很困难，但地理信息可辅助提出这种灾害制图的有关方法。描述了用于地理信息系统识别和定量计算不同地震滑坡危险区的技术方法，确定了地震烈度、地形坡度、岩土体类型和现存滑坡密度共4个因子参与的地震诱发滑坡危险性分析。在ARC／INFO DRID支持下，进行叠合分析，由此编制了云南省地震诱发滑坡危险区预测图。由地貌学家提出的地震诱发滑坡预测为规划和工程师提供了对区域规划和建筑工程有价值的技术方法。 相似文献
6.
EVOLUTION CHARACTERISTICS OF LANDSLIDES TRIGGERED BY 2008 MS8.0 WENCHUAN EARTHQUAKE IN YINGXIU AREA 
下载免费PDF全文
下载免费PDF全文 Strong earthquakes can not only trigger a large number of co-seismic landslides in mountainous areas, but also have an important impact on the development level of geological hazards in the disaster area. Usually, geological hazards caused by strong earthquakes will significantly increase and continue for a considerable period of time before they recover to the pre-earthquake level. Therefore, studying the evolution characteristics of landslides triggered by earthquake is particularly important for the prevention of geological disaster. In this paper, a 66km2 region in Yingxiu near the epicenter of the 2008 MS8.0 Wenchuan earthquake, which was strongly disturbed by the earthquake, was investigated. Firstly, one high-resolution satellite image before the earthquake(April, 2005) and five high-resolution satellite images after the earthquake(June, 2008; April, 2011; April, 2013; May, 2015; May, 2017)were used to interpret and catalog multi-temporal landslide inventories. Secondly, seven primary factors were analyzed in the GIS platform, including elevation, slope, aspect, curvature, stratum, lithology, and the distance from the nearest water system and the distance from seismogenic faults. Finally, the evolution of the landslide triggered by earthquake in this region was analyzed by comparing the landslide activity intensity in different periods, using the methods of correlation analysis, regression analysis, and single-factor statistical analysis. It was found that the total area of landslides in the study region decreased sharply from 2008 to 2017, with the area of the co-seismic landslide reducing from 21.41km2 to 1.33km2. This indicates that the magnitude of the landslides has recovered or is close to the pre-earthquake level. Moreover, correlation analysis shows that the elevation has a strong positive correlation with the distance from the nearest water system, and a weak positive correlation with the area. Meanwhile, there is a weak negative correlation between the distance from the nearest water system and the distance from seismogenic faults. Overall, the degree of landslide activity in the study region decreased over time, as well as the number of reactivated landslides and new landslides. The region where the area of earthquake triggered landslides decreased mainly concentrated at an elevation of 1 000m to 2 100m, a slope of 30° to 55°, an aspect of 40° to 180°, and a curvature of -2 to 2. In addition, the lithology of the Pengguan complex in the Yingxiu study region is more conducive to the occurrence of landslides, while the sedimentary rock is more conducive to the landslide recovery. When the distance from the nearest water system is more than 1 600m, the effect of the water system on the landslides gradually decreases. Also, the landslides triggered by Wenchuan earthquake in this area have the characteristics of the hanging wall effect, which means, the number of landslides in the northwestern region is much higher than that in the southeast side. 相似文献
7.
Summary statistics derived from the frequency–area distribution (FAD) of inventories of triggered landslides allows for direct comparison of landslides triggered by one event (e.g. earthquake, rainstorm) with another. Such comparisons are vital to understand links between the landslide‐event and the environmental characteristics of the area affected. This could lead to methods for rapid estimation of landslide‐event magnitude, which in turn could lead to estimates of the total triggered landslide area. Previous studies proposed that the FAD of landslides follows an inverse power‐law, which provides the basis to model the size distribution of landslides and to estimate landslide‐event magnitude (mLS), which quantifies the severity of the event. In this study, we use a much larger collection of earthquake‐induced landslide (EQIL) inventories (n=45) than previous studies to show that size distributions are much more variable than previously assumed. We present an updated model and propose a method for estimating mLS and its uncertainty that better fits the observations and is more reproducible, robust, and consistent than existing methods. We validate our model by computing mLS for all of the inventories in our dataset and comparing that with the total landslide areas of the inventories. We show that our method is able to estimate the total landslide area of the events in this larger inventory dataset more successfully than the existing methods. © 2018 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd. 相似文献
8.
为提高地震人员伤亡预评估的准确性,完善地震灾害损失评估模型,科学评估地震地质灾害可能造成的人员伤亡数量,以2014年鲁甸MS6.5地震滑坡人员死亡数据为样本,建立了一种基于公里网格单元的地震滑坡人员死亡率logistic回归模型。采用F检验法对所建模型的合理性进行检验,计算得到的F值无限接近于1,表明模型无限接近于完全模型,具有极好的数学统计意义。根据模型评估的死亡率反演得到鲁甸地震灾区滑坡致死人数为233人,比实际少17人,总精确度为93.20%,实际死亡人数与模型识别人数在空间上也有很好的一致性,说明计算得到的地震滑坡人员死亡率是实际死亡人数的良好指标。 相似文献
9.
XU Chong TIAN Ying-ying SHEN Ling-ling MA Si-yuan XU Xi-wei ZHOU Ben-gang HUANG Xue-qiang MA Jun-xue CHEN Xi 《地震地质》2018,40(5):1115-1128
In this study, a detailed database of landslides triggered by the 25 April 2015 Gorkha (Nepal)MW7.8 earthquake is constructed based on visual interpretation of pre- and post-earthquake high-resolution satellite images and field reconnaissance. Results show the earthquake triggered at least 47 200 landslides, which have a NWW direction spatial distribution, similar with the location and strike of the seismogenic fault. The landslides are of a total area about 110km2 and an oval distribution area about 35 700km2. On the basis of a scale relationship between landslide area (A)and volume (V), V=1.314 7×A1.208 5, the total volume of the coseismic landslides is estimated to be about 9.64×108m3. In the oval landslide distribution area, the landslide number density, area density, and volume density were calculated and the results are 1.32km-2, 0.31%, and 0.027m, respectively. This study provides a detailed and objective inventory of landslides triggered by the Gorkha earthquake, which provides very important and essential basic data for study of mechanics of coseismic landslides, spatial pattern, distribution law, and hazard assessment. In addition, the landslide database related to an individual earthquake also provides an important earthquake case in a subduction zone for studying landslides related to multiple earthquakes from a global perspective. 相似文献
10.
Defining the possible scenario of earthquake-induced landslides, Arias intensity is frequently used as a shaking parameter, being considered the most suitable for characterising earthquake impact, while Newmark׳s sliding-block model is widely used to predict the performance of natural slopes during earthquake shaking. In the present study we aim at providing tools for the assessment of the hazard related to earthquake-induced landslides at regional scale, by means of new empirical equations for the prediction of Arias intensity along with an empirical estimator of coseismic landslide displacements based on Newmark׳s model. The regression data, consisting of 205 strong motion recordings relative to 98 earthquakes, were subdivided into a training dataset, used to calculate equation parameters, and a validation dataset, used to compare the prediction performance among different possible functional forms and with equations derived from previous studies carried out for other regions using global and/or regional datasets. Equations predicting Arias intensities expected in Greece at known distances from seismic sources of defined magnitude proved to provide more accurate estimates if site condition and focal mechanism influence can be taken into account. Concerning the empirical estimator of Newmark displacements, we conducted rigorous Newmark analysis on 267 one-component records yielding a dataset containing 507 Newmark displacements, with the aim of developing a regression equation that is more suitable and effective for the seismotectonic environment of Greece and could be used for regional-scale seismic landslide hazard mapping. The regression analysis showed a noticeable higher goodness of fit of the proposed relations compared to formulas derived from worldwide data, suggesting a significant improvement of the empirical relation effectiveness from the use of a regionally-specific strong-motion dataset. 相似文献