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1.
An MW6.6 earthquake occurred in eastern Hokkaido, Japan on September 6th, 2018. Based on the pre-earthquake image from Google Earth and the post-earthquake image from high resolution (3 m) planet satellite, we manually interpret 9 293 coseismic landslides and select 7 influencing factors of seismic landslide, such as elevation, slope, slope direction, road distance, flow distance, peak ground acceleration (PGA) and lithology. Then, 9 293 landslide points are randomly divided into training samples and validation samples with a proportion of 7:3. In detail, the training sample has 6 505 landslide points and the validation sample has 2 788 landslide points. The hazard risk assessment of seismic landslide is conducted by using the information value method and the study area is further divided into five risk grades, including very low risk area, low risk area, moderate risk area high risk area and very high risk area. The results show that there are 7 576 landslides in high risk area and very high risk area, accounting for 81.52% of the total landslide number, and the landslide area is 22.93 km2, accounting for 74.35% of the total area. The hazard zoning is in high accordance with the actual situation. The evaluation results are tested by using the curve of cumulative percentage of hazardous area and cumulative percentage of landslides number. The results show that the success rate of the information value method is 78.50% and the prediction rate is 78.43%. The evaluation results are satisfactory, indicating that the hazard risk assessment results based on information value method may provide scientific reference for landslide hazard risk assessment as well as the disaster prevention and mitigation in the study area.  相似文献   
2.
《China Geology》2023,6(2):228-240
The Sichuan-Tibet transportation corridor is located at the eastern margin of the Qinghai-Tibet Plateau, where the complex topography and geological conditions, developed geo-hazards have severely restricted the planning and construction of major projects. For the long-term prevention and early control of regional seismic landslides, based on analyzing seismic landslide characteristics, the Newmark model was used to carry out the potential seismic landslide hazard assessment with a 50-year beyond probability 10%. The results show that the high seismic landslide hazard is mainly distributed along large active tectonic belts and deep-cut river canyons, and are significantly affected by the active tectonics. The low seismic landslide hazard is mainly distributed in the flat terrain such as the Quaternary basins, broad river valleys, and plateau planation planes. The major east-west linear projects mainly pass through five areas with high seismic landslide hazard: Luding-Kangding section, Yajiang-Xinlong (Yalong river) section, Batang-Baiyu (Jinsha river) section, Basu (Nujiang river) section, and Bomi-Linzhi (eastern Himalaya syntaxis) section. The seismic action of the Bomi-Linzhi section can also induce high-risk geo-hazard chains such as the high-level glacial lake breaks and glacial debris flows. The early prevention of seismic landslides should be strengthened in the areas with high seismic landslide hazard.©2023 China Geology Editorial Office.  相似文献   
3.
Earthquakes are a serious natural disaster faced by countries all over the world. Research on earthquake hazard mitigation are important parts of earthquake science and is a feature of China''s development of earthquake science. In recent years, the Ministry of Science and Technology (MOST) of the People''s Republic of China, the National Natural Science Foundation of China (NSFC) and the China Earthquake Administration (CEA) have attached great importance to basic research on earthquake hazard mitigation, and new opportunities and challenges have emerged. This paper collects the applications and approvals of the National Key R&D Program and the NSFC projects undertaken by the research institutes of the CEA system in recent years. The CEA system has received funding in the 13th “Five-year Plan” for “Monitoring, Early Warning and Prevention of Major Natural Disaster”. The implementation of these projects is expected to provide support for the basic science and applied research of the CEA system. In the NSFC, the number of applications from the CEA system is relatively stable, and the funding rate is slightly higher than the average for the department of earth science. Although no detailed statistical analysis has been performed, the CEA system still has room for improvement in the application of talent and major programs. I hope that the brief review of new opportunities that have arose in recent years described in this article can provide some background and new thinking for future challenges.  相似文献   
4.
地震滑坡危险性概念和基于力学模型的评估方法探讨   总被引:1,自引:0,他引:1  
在我国大陆地区运用基于力学模型的Newmark位移分析方法开展地震滑坡危险性定量评估,尚处在起步阶段.为了进一步明确地震滑坡危险性概念和改进推广基于力学模型的评估方法,首先阐明了狭义的地震滑坡危险性预测评估与震后反演评估的关系; 同时为了应对地震应急、震后重建及潜在地震条件下的不同评估需求,初步提出了广义的地震滑坡危险性评估框架.随后申述了基于Newmark位移分析的地震滑坡危险性评估方法的理论基础、方法分类及最新进展,并以汶川地震滑坡危险性快速评估为例,剖析了目前影响评估有效性的不确定性及空间数据质量等问题,指出了基于力学模型的地震滑坡危险性评估方法的改进方向.建议开展潜在地震及其诱发滑坡危险性的耦合评估,建立适用于我国大陆地区地震滑坡位移分析的经验模型,以便为国家层面的地震滑坡危险性区划服务.  相似文献   
5.
东北地区玉米不同生长阶段干旱冷害危险性评价   总被引:8,自引:2,他引:6  
利用东北地区35个农业气象站1961—2010年气象资料、玉米产量资料和1981—2010年玉米生育期资料,选用合适的干旱指标和冷害指标,结合自然灾害风险理论建立了灾害危险性评价模型。基于灾害判别结果和历史灾情资料,从典型灾害年中提取不同灾种的影响差异,构成权重系数,对东北地区玉米不同生长阶段和整个生育期干旱、冷害危险性进行评价。结果表明,东北地区干旱、冷害危险性在玉米生长前期(出苗—拔节阶段)主要集中在东北地区东南部,此阶段主要以冷害为主;而在玉米生长后期(抽雄—成熟阶段),风险高值区转移到西部,此阶段以干旱为主。生长前期和生长后期对整个生长阶段危险性的贡献值分别为0.3473和0.6527。东北地区的主要气象灾害正逐渐从冷害向干旱转变,冷害发生的频次逐渐减少,而干旱发生的频次快速增多,影响的范围也迅速增大。  相似文献   
6.
Disaster research and scholarship is now advocating a shift from focusing on the hazard event to processes that generate vulnerability and loss of resilience to disasters. Disaster legislations are among prominent instruments that can highlight the tensions as well as challenges that are being encountered towards this change in focus. Using textual analysis, this paper presents a study that investigated whether five post-2002 disaster legislations have shifted emphasis from the hazard to the vulnerability and resilience paradigms. The five examples illustrate that while there is a slight change, at least in rhetoric, from response to a prevention focus, disaster legislations largely promote a centralised institutional framework, with inadequate resource commitments and limited participation from vulnerable communities. Consequently, while generalisations simply cannot be made without a wider analysis of many more examples from different countries, the five disaster legislations appear to re-emphasise the response focus with less attention on the processes that reduce vulnerability and enhance resilience. The conclusion is that while the rhetoric has changed, the disaster legislations have not significantly moved from the hazard to vulnerability and resilience focus suggesting that reduction of losses and damages to disasters remains a big challenge  相似文献   
7.
The climatological characteristics of landfalling Gulf of Mexico hurricanes are presented, focusing on the basic parameters needed for accurately determining the structure and intensity of hurricanes for ocean response models. These include the maximum sustained wind, radius of maximum winds, the Holland-B parameter, the peripheral or far-field pressure, the surface roughness and coefficient of drag, and the central pressure for historical hurricanes in the Gulf.Despite evidence of a slight increase in the annual number of named storms over the past 50 years, presently there is no statistically significant trend in tropical storms, hurricanes, or major hurricanes in the Gulf of Mexico. In addition, the long-term variability of tropical cyclones in the Gulf reflects the observed variability in the Atlantic basin as a whole. Analyses of hurricane winds from multiple sources suggest the presence of a bias toward overestimating the strength of winds in the HURDAT dataset from 7% to 15%. Results presented comparing HURDAT with other sources also show an overestimation of intensity at landfall, with an estimated bias of ~10%.Finally, a review of recent studies has shown that hurricane frequencies and intensities appear to vary on a much more localized scale than previously believed. This exacerbates the sampling problem for accurate characterization of hurricane parameters for design and operational applications.  相似文献   
8.
云南鲁甸6.5级地震灾害特点浅析   总被引:5,自引:4,他引:1  
通过对2014年8月3日云南鲁甸6.5级地震震害开展实地调查,对灾区破坏情况进行总体介绍,并就各烈度区特征和建筑物震害、地震地质灾害、工程结构震害进行分析,初步得出本次地震的一些震害特点.一是灾区人口密度大,人员死亡较集中.人员死亡主要集中在Ⅷ和Ⅸ度区.二是地震振动强,灾区破坏严重.本次地震震源深度12km,极震区烈度高达Ⅸ度,震源破裂在11s内集中释放.三是抗震能力弱,房屋破坏严重.灾区属国家级贫困区,农村民居抗震能力弱,且多数民房坐落在河谷陡坡上,边坡效应加重房屋震害,重灾区砖木和土木房屋成片损毁、倒塌.四是灾区条件恶劣,救灾难度大.震区活动断裂密集发育、地质破碎疏松、地形崎岖不平,又恰值雨季,诱发极其严重次生地质灾害,导致人员伤亡,造成灾区大面积交通、通信、电力中断,救援物资与救援力量无法及时发挥作用.  相似文献   
9.
We present an Atlas of ShakeMaps and a catalog of human population exposures to moderate-to-strong ground shaking (EXPO-CAT) for recent historical earthquakes (1973–2007). The common purpose of the Atlas and exposure catalog is to calibrate earthquake loss models to be used in the US Geological Survey’s Prompt Assessment of Global Earthquakes for Response (PAGER). The full ShakeMap Atlas currently comprises over 5,600 earthquakes from January 1973 through December 2007, with almost 500 of these maps constrained—to varying degrees—by instrumental ground motions, macroseismic intensity data, community internet intensity observations, and published earthquake rupture models. The catalog of human exposures is derived using current PAGER methodologies. Exposure to discrete levels of shaking intensity is obtained by correlating Atlas ShakeMaps with a global population database. Combining this population exposure dataset with historical earthquake loss data, such as PAGER-CAT, provides a useful resource for calibrating loss methodologies against a systematically-derived set of ShakeMap hazard outputs. We illustrate two example uses for EXPO-CAT; (1) simple objective ranking of country vulnerability to earthquakes, and; (2) the influence of time-of-day on earthquake mortality. In general, we observe that countries in similar geographic regions with similar construction practices tend to cluster spatially in terms of relative vulnerability. We also find little quantitative evidence to suggest that time-of-day is a significant factor in earthquake mortality. Moreover, earthquake mortality appears to be more systematically linked to the population exposed to severe ground shaking (Modified Mercalli Intensity VIII+). Finally, equipped with the full Atlas of ShakeMaps, we merge each of these maps and find the maximum estimated peak ground acceleration at any grid point in the world for the past 35 years. We subsequently compare this “composite ShakeMap” with existing global hazard models, calculating the spatial area of the existing hazard maps exceeded by the combined ShakeMap ground motions. In general, these analyses suggest that existing global, and regional, hazard maps tend to overestimate hazard. Both the Atlas of ShakeMaps and EXPO-CAT have many potential uses for examining earthquake risk and epidemiology. All of the datasets discussed herein are available for download on the PAGER Web page (). T. I. Allen and M. G. Hearne—contracted through Synergetics Incorporated.  相似文献   
10.
《The Journal of geography》2012,111(6):258-266
Abstract

People generally do not perceive New England to be tornado-prone. Yet, there is a long history of such storms in the six states going back to the late seventeenth century. Usually, New England tornadoes are small and short-lived; even so, some have caused many deaths and much property damage. There is a greater probability for a person to be affected by a tornado in southern New England than in much of the American Midwest. As building and population density increases, so does the hazard potential. Data from awareness surveys indicate that the lack of tornado knowledge remains a serious problem for teachers, students, and the public, and government information about such storms is not being widely disseminated.  相似文献   
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