Inversion of near-field waveform data for earthquake source rupture process (Ⅱ): Inversion of Chi Chi earthquake source, 20 September, 1999, Taiwan     

《中国科学D辑(英文版)》2006,(3)

The Chi Chi earthquake (Mw7.6) occurred at 17:47 UTC on Sept. 20,1999 (01:47 September 21, 1999, local time) in central Taiwan. CWB located the epi- center at (120.82°E; 23.85°N) and the focal depth 8 km. Chi Chi earthquake is the best documented earth- quake ever recorded. The abundance and quality of its near-source observations present an unparalleled op- portunity for studying the rupture history from a close distance. More than 400 free field digital accelerome- ters with 3-compon…  相似文献   

Sumatra tsunami: lessons from modeling   总被引：1，自引：0，他引：1  

Diego Arcas  Vasily Titov 《Surveys in Geophysics》2006,27(6):679-705

The need for the combination of seismic data with real-time wave height information for an effective prediction of tsunami impact is emphasized in the paper. A preliminary, but comprehensive study of arrival times, wave heights and run-up values at a number of locations and tide gage stations throughout the Indian Ocean seaboard is presented. Open ocean wave height data from satellite observations are analyzed and used in the reconstruction of a tsunami source mechanism for the December 26, 2004 event. The reconstructed source is then used to numerically estimate tsunami impact along the Indian Ocean seaboard, including wave height, and arrival times at 12 tide gage stations, and inundation at 3 locations on the coast of India. The December 2004, as well as the March 28, 2005 tsunamis are investigated and their differences in terms of tsunami generation are analyzed and presented as a clear example of the need for both, seismic and real-time tsunami data for a reliable tsunami warning system in the Indian Ocean.  相似文献   

A preliminary investigation of strong-motion data from the French Antilles     

John Douglas  Didier Bertil  Agathe Roullé  Pascal Dominique  Philippe Jousset 《Journal of Seismology》2006,10(3):271-299

Strong-motion networks have been operating in the Caribbean region since the 1970s, however, until the mid-1990s only a few analogue stations were operational and the quantity of data recorded was very low. Since the mid-1990s, digital accelerometric networks have been established on islands within the region. At present there are thought to be about 160 stations operating in this region with a handful on Cuba, 65 on the French Antilles (mainly Guadeloupe and Martinique), eight on Jamaica, 78 on Puerto Rico (plus others on adjacent islands) and four on Trinidad.After briefly summarising the available data from the Caribbean islands, this article is mainly concerned with analysing the data that has been recorded by the networks operating on the French Antilles in terms of their distribution with respect to magnitude, source-to-site distance, focal depth and event type; site effects at certain stations; and also with respect to their predictability by ground motion estimation equations developed using data from different regions of the world. More than 300 good quality triaxial acceleration time-histories have been recorded on Guadeloupe and Martinique at a large number of stations from earthquakes with magnitudes larger than 4.8, however, most of the records are from considerable source-to-site distances. From the data available it is found that many of the commonly-used ground motion estimation equations for shallow crustal earthquakes poorly estimate the observed ground motions on the two islands; ground motions on Guadeloupe and Martinique have smaller amplitudes and are more variable than expected. This difference could be due to regional dependence of ground motions because of, for example, differing tectonics or crustal structures or because the ground motions so far recorded are, in general, from smaller earthquakes and greater distances than the range of applicability of the investigated equations.  相似文献   

Seasonal fluctuations in the deep central equatorial Atlantic Ocean: a data–model comparison     

Virginie Thierry  Herlé Mercier  Anne Marie Treguier 《Ocean Dynamics》2006,56(5-6):581-593

Low-frequency current fluctuations in the deep central equatorial Atlantic are analyzed using current meter measurements recorded from November 1992 to November 1994. Current meters were located at about 14°W of longitude and 1° of latitude on both sides of the equator between 1,700 m depth and the ocean bottom. At all sampling depths, the velocity fluctuations are dominantly zonal and symmetrical with respect to the equator. At 1,700 and 2,000 m, the flow is dominated by annual period fluctuations, at 3,000 m, the velocity field amplitude presents a minimum, and at 3,750 and 3,950 m, the flow is modulated by annual and semiannual period variability. The annual signal exhibits an apparent upward phase propagation. When considering the phase and the amplitude of the seasonal fluctuations, the data compare well with the outputs of a realistic numerical simulation of the Atlantic Ocean. Together with a previous analysis of the model simulations, this supports the idea that the observed annual fluctuations are due to wind-forced vertically propagating Kelvin and Rossby waves. Data and model do not provide deciding evidences of the presence of semiannual equatorial waves deeper than 3,500 m depth in the central equatorial Atlantic Ocean.  相似文献   

浅议如何提高地震前兆观测数据的质量     

张正霞 《山西地震》2006,(4):38-39

文中论述了地震前兆观测数据的采集、处理、入库、报送和共享等具体工作,指出了当前数据报送工作中存在的问题,提出了改进措施,以保障前兆观测数据的连续、完整。为地震监测预报提供可信度较高的资料。  相似文献   

"九五"前兆公用数据采集器的存储扩展问题     

周振安  王秀英  刘爱春  郭柏林 《地震研究》2006,29(3):286-289

为了解决“九五”数字化地震前兆台站公用数据采集器存储空间过小的问题，对公用数据采集器的数据存储卡进行了重新设计。详细介绍了设计思想及其实现方法，并通过现场实验观测证明，新设计能较好地满足用户需求。  相似文献   

地震安全性评价数据的集中管理     

聂树明  李宏志  杜鹏 《国际地震动态》2006,(2):26-28

本文分析了目前地震安全性评价数据管理的现状和数据集中管理的优势,提出了实现集中管理地震安全性评价数据的技术,以及数据安全防护措施。  相似文献   

基于VTK的医学图像系统研究   总被引：6，自引：0，他引：6  

刘志健  王蓉  刘玉玲  余飞鸿 《CT理论与应用研究》2006,15(2):38-42

医学三维数据场可视化是当前科学计算可视化应用的重点。本文论述了可视化工具包VisualizationToolkit(VTK)的主要特点,介绍了三维医学可视化系统实现的原理和方法。根据一系列人体断面图像,应用VTK实现了三维医学图像重构,对重构后的三维图像进行解剖分析;并实现对人体的二维图像逐帧浏览及柱状统计。实验结果表明,VTK具有使用灵活,功能强大的优点,是医学三维数据场可视化的有力工具。  相似文献   

中国大陆科学钻探孔区全观式三维地震采集   总被引：8，自引：3，他引：8       下载免费PDF全文

杨文采  刘光林  杨锴  程振炎 《地球物理学报》2006,49(3):735-744

大陆科学钻探不仅是打一口钻，而是深部钻探同地球物理遥测结合起来的相互反馈系统，这里地球物理遥测主要是指三维深反射地震. 中国大陆科学钻探孔区三维地震调查是大陆科学钻探工程的一项重要内容. 在数据采集中提出了全观式三维地震调查新技术，它是指排列不滚动的三维地震调查，即将地震检波器铺满全部测区的一种地震采集方法，尤其适合于有限面积的三维地震工作. 这种方法的优点是：(1)快速高效; (2)叠加次数高; (3)与常规三维地震相比成本大幅度减少. 在中国大陆科学钻探孔区内进行的全观式三维地震测量，全面实现了预期目标,包括：(1) 配合钻探查明孔区地质构造，将钻探的一孔之见扩展到深6000m、长宽超过3000m的三维岩柱；(2)提供高精度定位的地壳反射体以供标定；(3)发现中、下地壳及地幔内的反射体等.  相似文献   

地震资料解释中的误区与科学思维     

卢君实 《中国煤田地质》2006,18(6):46-49

地震资料解释是地震勘探的核心环节,但地震资料解释人员一些认识上误区在一定程度上制约了着它的发展。通过实例,介绍了当前的资料解释人员存在的七种主要误区,并分别对这些认识误区进行了深入的分析,探讨其错误实质及危害,以帮助资料解释人员树立一种地震资料解释的科学思维,提高地震资料解释水平。  相似文献