A GIS-based Earthquake and Tsunami Emergency Command System for Seaside Cities   总被引：1，自引：0，他引：1  

GUAN Youhai FENG Qimin JIA Jing 《中国海洋大学学报(英文版)》2006,5(2):181-186

In this paper the geographical information system （GIS） is applied to earthquake and tsunami emergency work and an earthquake and tsunami emergency command system （ETECS） for seaside cities is developed which is composed of a basic database and six subsystems. By employing this system, the responsible municipal departments can make rapid prediction before the occurrence of earthquake or tsunami, make commanding decisions concerning the disaster-fight during the disastrous event, and make rapid estimates of the casualties and economic losses. So that the government could conduct relief work in time and planning for future disaster reduction and prevention.  相似文献   

Distribution and sedimentary characteristics of tsunami deposits along the Cascadia margin of western North America   总被引：1，自引：0，他引：1  

Robert Peters  Bruce Jaffe  Guy Gelfenbaum 《Sedimentary Geology》2007,200(3-4):372-386

Tsunami deposits have been found at more than 60 sites along the Cascadia margin of Western North America, and here we review and synthesize their distribution and sedimentary characteristics based on the published record. Cascadia tsunami deposits are best preserved, and most easily identified, in low-energy coastal environments such as tidal marshes, back-barrier marshes and coastal lakes where they occur as anomalous layers of sand within peat and mud. They extend up to a kilometer inland in open coastal settings and several kilometers up river valleys. They are distinguished from other sediments by a combination of sedimentary character and stratigraphic context. Recurrence intervals range from 300–1000 years with an average of 500–600 years. The tsunami deposits have been used to help evaluate and mitigate tsunami hazards in Cascadia. They show that the Cascadia subduction zone is prone to great earthquakes that generate large tsunamis. The inclusion of tsunami deposits on inundation maps, used in conjunction with results from inundation models, allows a more accurate assessment of areas subject to tsunami inundation. The application of sediment transport models can help estimate tsunami flow velocity and wave height, parameters which are necessary to help establish evacuation routes and plan development in tsunami prone areas.  相似文献   

The December 26th 2004 Tsunami Recorded along the Southeastern Coast of Brazil     

Carlos A. S. França  Afranio R. De Mesquita 《Natural Hazards》2007,40(1):209-222

Sea level measurements along the southeastern Brazilian coast, between 20° S and 30° S, show the effect of the Sumatra Tsunami of December 26, 2004. Two records from stations, one located inside an estuary and other inside a bay, shows oscillations of about 0.20 m range; one additional record from a station facing the open sea shows up to 1.2 m range oscillations. These oscillations have around 45 min period, starting 20–22 h after the Sumatra earthquake in the Indian Ocean (00:59 UTC) and lasting for 2 days. A computer modelling of the event reproduces the time of arrival of long shallow-water tsunami waves at the southeastern Brazilian coast but with slight longer period and amplitudes smaller than observed at the coast, probably due to its coarse resolution (1/4 of a degree). The high amplitudes observed at the coast suggest a mechanism of amplification of these waves over the southeastern Brazilian shelf.  相似文献   

Distribution, origin and transport process of boulders deposited by the 2004 Indian Ocean tsunami at Pakarang Cape, Thailand     

Kazuhisa Goto  Suchana A. Chavanich 《Sedimentary Geology》2007,202(4):821-837

The tsunami of 2004 in the Indian Ocean transported thousands of meters-long boulders shoreward at Pakarang Cape, Thailand. We investigated size, position and long axis orientation of 467 boulders at the cape. Most of boulders found at the cape are well rounded, ellipsoid in shape, without sharp broken edges. They were fragments of reef rocks and their sizes were estimated to be < 14m³ (22.7t). The distribution pattern and orientation of long axis of boulders reflect the inundation pattern and behavior of the tsunami waves. It was found that there is no clear evidence indicating monotonous fine/coarse shoreward trends of these boulders along each transect line. On the other hand, the large boulders were deposited repeatedly along the three arcuate lines at the intertidal zone with a spacing of approximately 136m interval. This distribution pattern may suggest that long-lasting oscillatory flows might have repositioned the boulders and separated the big ones from small. No boulders were found on land, indicating that the hydraulic force of the tsunami wave rapidly dissipated on reaching the land due to the higher bottom friction and the presence of a steep slope. We further conducted numerical calculation of tsunami inundation at Pakarang Cape. According to the calculation, the sea receded and the major part of the tidal bench (area with boulders at present) was exposed above the sea surface before the arrival of the first tsunami wave. The first tsunami wave arrived at the cape from west to east at approximately 130min after the tsunami generation, and then inundated inlands. Our calculation shows that tsunami wave was focused around the offshore by a small cove at the reef edge and spread afterwards in a fan-like shape on the tidal bench. The critical wave velocities necessary to move the largest and average-size boulders by sliding can be estimated to be approximately 3.2 and 2.0m/s, respectively. The numerical result indicates that the maximum current velocity of the first tsunami wave was estimated to be from 8 to 15m/s between the reef edge and approximately 500m further offshore. This range is large enough for moving even the largest boulder shoreward. These suggest that the tsunami waves that were directed eastward, struck the reef rocks and coral colonies, originally located on the shallow sea bottom near the reef edge, and detached and transported the boulders shoreward.  相似文献   

多种海啸触发类型的流固耦合数值模拟初步研究     

刘双庆  朱元清  薛艳  温艳玲 《地震地磁观测与研究》2007,28(5):130-137

利用有限元流固耦合理论来模拟二维、三维海啸触发阶段的动态过程,将海啸可能的触发类型分离出来独自模拟分析,并解决了触发过程中,流固计算可能失效而面临的问题,从形变图,压强图以及能量图多侧面地表达出流固耦合在海啸触发模拟中的可行性.由于不需要进行浅水波近似,因此所使用的计算方法和结果可推到较广的使用范围.  相似文献   

海啸传播模型与数值模拟研究进展   总被引：1，自引：0，他引：1  

温燕玲  朱元清 《地震地磁观测与研究》2007,28(5):143-149

海啸在浅水大陆架的传播问题由于其非线性作用和浅水效应而变得十分复杂,然而目前成熟的海啸传播理论及数值模拟结果在这方面与实际并不一致.本文比较分析了可用来模拟大陆架海啸传播的浅水波模型和数值方法,并提出对我国东海陆架边缘可能发生的近海海啸需要开展数值试验研究.  相似文献   

Field Survey of Tsunami Effects in Sri Lanka due to the Sumatra-Andaman Earthquake of December 26, 2004     

Shusaku Inoue  Anil C. Wijeyewickrema  Hiroyuki Matsumoto  Hiroyuki Miura  Priyantha Gunaratna  Manoj Madurapperuma  Toru Sekiguchi 《Pure and Applied Geophysics》2007,164(2-3):395-411

The December 26, 2004 Sumatra-Andaman earthquake that registered a moment magnitude (M_w) of 9.1 was one of the largest earthquakes in the world since 1900. The devastating tsunami that resulted from this earthquake caused more casualties than any previously reported tsunami. The number of fatalities and missing persons in the most seriously affected countries were Indonesia - 167,736, Sri Lanka - 35,322, India - 18,045 and Thailand - 8,212. This paper describes two field visits to assess tsunami effects in Sri Lanka by a combined team of Japanese and Sri Lankan researchers. The first field visit from December 30, 2004 – January 04, 2005 covered the western and southern coasts of Sri Lanka including the cities of Moratuwa, Beruwala, Bentota, Pereliya, Hikkaduwa, Galle, Talpe, Matara, Tangalla and Hambantota. The objectives of the first field visit were to investigate the damage caused by the tsunami and to obtain eyewitness information about wave arrival times. The second field visit from March 10–18, 2005 covered the eastern and southern coasts of Sri Lanka and included Trincomalee, Batticaloa, Arugam Bay, Yala National Park and Kirinda. The objectives of the second visit were mainly to obtain eyewitness information about wave arrival times and inundation data, and to take relevant measurements using GPS instruments.  相似文献   

Tsunami Assessment for Risk Management at Nuclear Power Facilities in Japan     

Ken Yanagisawa  Fumihiko Imamura  Tsutomu Sakakiyama  Tadashi Annaka  Tomoyoshi Takeda  Nobuo Shuto 《Pure and Applied Geophysics》2007,164(2-3):565-576

The present study focuses on evaluation of the maximum and minimum water levels caused by tsunamis as risk factors for operation and management at nuclear power facilities along the coastal area of Japan. Tsunamis generated by submarine earthquakes are examined, basing literature reviews and databases of information on historical tsunami events and run-up heights. For simulation of water level along the coast, a numerical calculation system should be designed with computational regions covering a particular site. Also the calculation system should be verified by comparison of historical and calculated tsunami heights. At the beginning of the tsunami assessment, the standard faults, their locations, mechanisms and maximum magnitudes should be carefully estimated by considering historical earthquake-induced tsunamis and seismo-tectonics at each area. Secondly, the range of errors in the model parameters should be considered since earthquakes and tsunamis are natural phenomena that involve natural variability as well as errors in estimating parameters. For these reasons, uncertainty-induced errors should be taken into account in the process of tsunami assessment with parametric study of the tsunami source model. The element tsunamis calculated by the standard fault models with the errors would be given for the design. Then, the design tsunami can be selected among the element tsunamis with the most significant impact, maximum and minimum water levels, on the site, bearing in mind the possible errors in the numerical calculation system. Finally, the design tsunami is verified by comparison with the run-up heights of historical tsunamis, ensuring that the design tsunami is selected as the highest of all historical and possible future tsunamis at the site.  相似文献   

Tsunami and its Hazard in the Indian and Pacific Oceans: Introduction   总被引：1，自引：0，他引：1  

K. Satake  E. A. Okal  J. C. Borrero 《Pure and Applied Geophysics》2007,164(2-3):249-259

The 2004 Indian Ocean tsunami caused an estimated 230,000 casualties, the worst tsunami disaster in history. A similar-sized tsunami in the Pacific Ocean, generated by the 1960 Chilean earthquake, commenced international collaborations on tsunami warning systems, and in the tsunami research community through the Tsunami Commission of International Union of Geodesy and Geophysics. The IUGG Tsunami Commission, established in 1960, has been holding the biannual International Tsunami Symposium (ITS). This volume contains selected papers mostly presented at the 22nd ITS, held in the summer of 2005. This introduction briefly summarizes the progress of tsunami and earthquake research as well as international cooperation on tsunami warning systems and the impact of the 2004 tsunami. Brief summaries of each paper are also presented.  相似文献   

Volcanogenic Tsunamis in Lakes: Examples from Nicaragua and General Implications   总被引：1，自引：0，他引：1  

Armin Freundt  Wilfried Strauch  Steffen Kutterolf  Hans-Ulrich Schmincke 《Pure and Applied Geophysics》2007,164(2-3):527-545

This paper emphasizes the fact that tsunamis can occur in continental lakes and focuses on tsunami triggering by processes related to volcanic eruptions and instability of volcanic edifices. The two large lakes of Nicaragua, Lake Managua and Lake Nicaragua, host a section of the Central American Volcanic Arc including several active volcanoes. One case of a tsunami in Lake Managua triggered by an explosive volcanic eruption is documented in the geologic record. However, a number of events occurred in the past at both lakes which were probably tsunamigenic. These include massive intrusion of pyroclastic flows from Apoyo volcano as well as of flank-collapse avalanches from Mombacho volcano into Lake Nicaragua. Maar-forming phreatomagmatic eruptions, which repeatedly occurred in Lake Managua, are highly explosive phenomena able to create hugh water waves as was observed elsewhere. The shallow water depth of the Nicaraguan lakes is discussed as the major limiting factor of tsunami amplitude and propagation speed. The very low-profile shores facilitate substantial in-land flooding even of relatively small waves. Implications for conceiving a possible warning system are also discussed.  相似文献