排序方式: 共有18条查询结果,搜索用时 15 毫秒
1.
考虑震源破裂过程的青海玉树地震震动图研究 总被引:4,自引:0,他引:4
为了在缺少实时台站数据的情况下,研究震后地表地震动分布,本文尝试通过对震源做出某些约束,以提高震动图的精度.由于青海玉树地震的发震断层近似直立(倾向83°),震源破裂过程在时间和空间上呈明显的分区特征,分别考虑了地表破裂的线源发生模型和主震震级分解方法,用考虑了场地效应的震动图快速生成方法生成震动图.将两种方法生成的震动图与调查烈度比较.结果表明,基于震源破裂过程对主震震级进行分解,综合考虑各子事件生成震动图的方法,对震后的应急决策和灾情的快速评估是可行的. 相似文献
2.
John Douglas 《Bulletin of Earthquake Engineering》2007,5(3):363-376
Accurate estimates of the ground motions that occurred during damaging earthquakes are a vital part of many aspects of earthquake
engineering, such as the study of the size and cause of the uncertainties within earthquake risk assessments. This article
compares a number of methods to estimate the ground shaking that occurred on Guadeloupe (French Antilles) during the 21st
November 2004 (M
w
6.3) Les Saintes earthquake, with the aim of providing more accurate shaking estimates for the investigation of the sources
of uncertainties within loss evaluations, based on damage data from this event. The various techniques make differing use
of the available ground-motion recordings of this earthquake and by consequence the estimates obtained by the different approaches
are associated with differing uncertainties. Ground motions on the French Antilles are affected by strong local site effects,
which have been extensively investigated in previous studies. In this article, use is made of these studies in order to improve
the shaking estimates. It is shown that the simple methods neglecting the spatial correlation of earthquake shaking lead to
uncertainties similar to those predicted by empirical ground-motion models and that these are uniform across the whole of
Guadeloupe. In contrast, methods (such as the ShakeMap approach) that take account of the spatial correlation in motions demonstrate
that shaking within roughly 10 km of a recording station (covering a significant portion of the investigated area) can be
defined with reasonable accuracy but that motions at more distant points are not well constrained. 相似文献
3.
4.
5.
本论文内容涵盖传感器组网,数据获取、存储、管理、迁移与服务,以及地震动参数计算与发布等检测系统各个环节,在研究过程中,以地震动参数速报技术研究为主题,并注意把相关的技术应用在实际的工作中。“基于IPV6对地震烈度传感器网络”部分直接使用了ShakeMap开发过程中有关数据流的接收、服务,操作系统的重编译,事件检测,图片产出, 相似文献
6.
Trevor I. Allen David J. Wald Paul S. Earle Kristin D. Marano Alicia J. Hotovec Kuowan Lin Michael G. Hearne 《Bulletin of Earthquake Engineering》2009,7(3):701-718
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
7.
We developed a Real-time Online earthquake Simulation system (ROS) to simulate regional earthquakes in Taiwan. The ROS uses a centroid moment tensor solution of seismic events from a Real-time Moment Tensor monitoring system (RMT), which provides all the point source parameters including the event origin time, hypocentral location, moment magnitude and focal mechanism within 2 min after the occurrence of an earthquake. Then, all of the source parameters are automatically forwarded to the ROS to perform an earthquake simulation, which is based on a spectral-element method (SEM). A new island-wide, high resolution SEM mesh model is developed for the whole Taiwan in this study. We have improved SEM mesh quality by introducing a thin high-resolution mesh layer near the surface to accommodate steep and rapidly varying topography. The mesh for the shallow sedimentary basin is adjusted to reflect its complex geometry and sharp lateral velocity contrasts. The grid resolution at the surface is about 545 m, which is sufficient to resolve topography and tomography data for simulations accurate up to 1.0 Hz. The ROS is also an infrastructural service, making online earthquake simulation feasible. Users can conduct their own earthquake simulation by providing a set of source parameters through the ROS webpage. For visualization, a ShakeMovie and ShakeMap are produced during the simulation. The time needed for one event is roughly 3 min for a 70 s ground motion simulation. The ROS is operated online at the Institute of Earth Sciences, Academia Sinica (http://ros.earth.sinica.edu.tw/). Our long-term goal for the ROS system is to contribute to public earth science outreach and to realize seismic ground motion prediction in real-time. 相似文献
8.
9.
2010年4月14日青海玉树地震震动图 总被引:5,自引:1,他引:4
在2010年4月14日07时49分(北京时间)青海省玉树藏族自治州玉树县(33.2°N,96.6°E)7.1级地震发生后,综合考虑震中地区的地质构造背景、活动断裂分布、震源机制结果、震源破裂过程、我国西部的地震动参数经验衰减关系及局部场地效应的影响,用考虑场地效应的震动图快速生成方法,在震后约2小时后得到玉树地震震中地区的震动图,并提供给相关部门使用.结果表明,此次地震的地震烈度特征预测如下:①烈度的展布方向NW-SE向,与玉树断裂的走向一致;②极震区的烈度为Ⅸ度,面积约为300km2;③烈度Ⅸ度区主要位于震中东南方向沿断裂走向近40km和西北方向沿断裂走向15km之间的区域;④Ⅸ度区的西北端由于局部场地条件的影响,其烈度由基岩参考面的Ⅸ度区降为土层上的Ⅷ度区;⑤Ⅷ度区面积约为3000km2;⑥Ⅶ度区的面积约为8000km2;⑦Ⅵ度区面积约为24000km2. 相似文献
10.