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Integrated Historical Tsunami Event and Deposit Database  

Science.gov (United States)

The National Geophysical Data Center (NGDC) provides integrated access to historical tsunami event, deposit, and proxy data. The NGDC tsunami archive initially listed tsunami sources and locations with observed tsunami effects. Tsunami frequency and intensity are important for understanding tsunami hazards. Unfortunately, tsunami recurrence intervals often exceed the historic record. As a result, NGDC expanded the archive to include the Global Tsunami Deposits Database (GTD_DB). Tsunami deposits are the physical evidence left behind when a tsunami impacts a shoreline or affects submarine sediments. Proxies include co-seismic subsidence, turbidite deposits, changes in biota following an influx of marine water in a freshwater environment, etc. By adding past tsunami data inferred from the geologic record, the GTD_DB extends the record of tsunamis backward in time. Although the best methods for identifying tsunami deposits and proxies in the geologic record remain under discussion, developing an overall picture of where tsunamis have affected coasts, calculating recurrence intervals, and approximating runup height and inundation distance provides a better estimate of a region’s true tsunami hazard. Tsunami deposit and proxy descriptions in the GTD_DB were compiled from published data found in journal articles, conference proceedings, theses, books, conference abstracts, posters, web sites, etc. The database now includes over 1,200 descriptions compiled from over 1,100 citations. Each record in the GTD_DB is linked to its bibliographic citation where more information on the deposit can be found. The GTD_DB includes data for over 50 variables such as: event description (e.g., 2010 Chile Tsunami), geologic time period, year, deposit location name, latitude, longitude, country, associated body of water, setting during the event (e.g., beach, lake, river, deep sea), upper and lower contacts, underlying and overlying material, etc. If known, the tsunami source mechanism (e.g., earthquake, landslide, volcanic eruption, asteroid impact) is also specified. Observations (grain size, sedimentary structure, bed thickness, number of layers, etc.) are stored along with the conclusions drawn from the evidence by the author (wave height, flow depth, flow velocity, number of waves, etc.). Geologic time periods in the GTD_DB range from Precambrian to Quaternary, but the majority (70%) are from the Quaternary period. This period includes events such as: the 2004 Indian Ocean tsunami, the Cascadia subduction zone earthquakes and tsunamis, the 1755 Lisbon tsunami, the A.D. 79 Vesuvius tsunami, the 3500 BP Santorini caldera collapse and tsunami, and the 7000 BP Storegga landslide-generated tsunami. Prior to the Quaternary period, the majority of the paleotsunamis are due to impact events such as: the Tertiary Chesapeake Bay Bolide, Cretaceous-Tertiary (K/T) Boundary, Cretaceous Manson, and Devonian Alamo. The tsunami deposits are integrated with the historical tsunami event database where applicable. For example, users can search for articles describing deposits related to the 1755 Lisbon tsunami and view those records, as well as link to the related historic event record. The data and information may be viewed using tools designed to extract and display data (selection forms, Web Map Services, and Web Feature Services).

Dunbar, P. K.; McCullough, H. L.

2010-12-01

2

Seismically generated tsunamis.  

UK PubMed Central (United Kingdom)

People around the world know more about tsunamis than they did 10 years ago, primarily because of two events: a tsunami on 26 December 2004 that killed more than 200,000 people around the shores of the Indian Ocean; and an earthquake and tsunami off the coast of Japan on 11 March 2011 that killed nearly 15,000 more and triggered a nuclear accident, with consequences that are still unfolding. This paper has three objectives: (i) to summarize our current knowledge of the dynamics of tsunamis; (ii) to describe how that knowledge is now being used to forecast tsunamis; and (iii) to suggest some policy changes that might protect people better from the dangers of future tsunamis.

Arcas D; Segur H

2012-04-01

3

Seismically generated tsunamis.  

Science.gov (United States)

People around the world know more about tsunamis than they did 10 years ago, primarily because of two events: a tsunami on 26 December 2004 that killed more than 200,000 people around the shores of the Indian Ocean; and an earthquake and tsunami off the coast of Japan on 11 March 2011 that killed nearly 15,000 more and triggered a nuclear accident, with consequences that are still unfolding. This paper has three objectives: (i) to summarize our current knowledge of the dynamics of tsunamis; (ii) to describe how that knowledge is now being used to forecast tsunamis; and (iii) to suggest some policy changes that might protect people better from the dangers of future tsunamis. PMID:22393107

Arcas, Diego; Segur, Harvey

2012-04-13

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Landslide tsunami case studies using a Boussinesq model and a fully nonlinear tsunami generation model  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Case studies of landslide tsunamis require integration of marine geology data and interpretations into numerical simulations of tsunami attack. Many landslide tsunami generation and propagation models have been proposed in recent time, further motivated by the 1998 Papua New Guinea event. However, f...

Watts, P.; Grilli, S. T.; Kirby, J. T.; Fryer, G. J.; Tappin, D. R.

5

Tsunami  

Medline Plus

Full Text Available ... of a tsunami can be mitigated through community preparedness, timely warnings, and effective response. NOAA has primary ... Marine Debris from the Japanese Tsunami New! Tsunami Preparedness Week March 24-30, 2013 Recent Tsunami Events ...

6

Tsunami  

Medline Plus

Full Text Available ... What's happening now? Tsunami YouTube videos Feature Archive Basics: The Tsunami Story : Generation, propagation, warning systems, forecasts and reduction of impacts. Basic information about Tsunamis Tsunami Terminology NOAA's Role NOAA's ...

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PREDICTION OF SLUMP GENERATED TSUNAMIS: THE JULY 17TH 1998 PAPUA NEW GUINEA EVENT  

Directory of Open Access Journals (Sweden)

Full Text Available The local tsunami of July 17th 1998 that struck Papua New Guinea is most probably the result of an offshore sediment slump. This conclusion is based on multibeam bathymetric data, visual ob- servation of the seabed, and sediment piston cores. Offshore data has been utilised to interpret the tectonic framework of the area off northern PNG, the local sedimentary regime and, from this and onshore evidence of sediment dispersal a model of sediment failure has been con- structed. Utilising the seabed observations, the distribution of seabed failure has been mapped and the tsunami source location accurately identified. Fluid expulsion from the sediment has been assessed from the presence of authigenic carbonates and chemosynthetic communities. It is proposed that multibeam bathymetry, sediment sampling, and visual seabed observation are critical in the identification of coastlines vulnerable to tsunami attack and, in combination with onshore studies and numerical simulations, tsunami prone areas may be identified. Ultimately, as more case studies are undertaken, underwater landslide prediction may at last become possi- ble.

David R. Tappin; Philip Watts; Gary M. McMurtry; Yves Lafoy; Takeshi Matsumoto

2002-01-01

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Advanced Simulation of Coupled Earthquake and Tsunami Events  

Science.gov (United States)

Tsunami-Earthquakes represent natural catastrophes threatening lives and well-being of societies in a solitary and unexpected extreme event as tragically demonstrated in Sumatra (2004), Samoa (2009), Chile (2010), or Japan (2011). Both phenomena are consequences of the complex system of interactions of tectonic stress, fracture mechanics, rock friction, rupture dynamics, fault geometry, ocean bathymetry, and coastline geometry. The ASCETE project forms an interdisciplinary research consortium that couples the most advanced simulation technologies for earthquake rupture dynamics and tsunami propagation to understand the fundamental conditions of tsunami generation. We report on the latest research results in physics-based dynamic rupture and tsunami wave propagation simulation, using unstructured and adaptive meshes with continuous and discontinuous Galerkin discretization approaches. Coupling both simulation tools - the physics-based dynamic rupture simulation and the hydrodynamic tsunami wave propagation - will give us the possibility to conduct highly realistic studies of the interaction of rupture dynamics and tsunami impact characteristics.

Behrens, Joern

2013-04-01

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On the modelling of tsunami generation and tsunami inundation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

While the propagation of tsunamis is well understood and well simulated by numerical models, there are still a number of unanswered questions related to the generation of tsunamis or the subsequent inundation. We review some of the basic generation mechanisms as well as their simulation. In particul...

Dias, Frédéric; Dutykh, Denys; O'Brien, Laura; Renzi, Emiliano; Stefanakis, Themistoklis

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Tsunami warning in French Polynesia during the 2009 Samoa event  

Science.gov (United States)

An effective tsunami warning was in effect in French Polynesia for the big Samoa event on September 2009; a rapid warning was generated from the seismic parameters obtained via near real-time processing. Different methods were used to characterize and quantify the source parameters like: evolving scalar moment along the time, average mantle magnitude Mm, slowness, and use of the new concept of magnitude with the W phase. The expected tsunami amplitudes were estimated from seismic parameters such obtained, and were communicated to Civil Defense; a red warning was then broadcasted to population during about one hour (2 hours in Marquesas). In fact, French Polynesia was spared by the tsunami, with relatively weak amplitudes in Society Island, and, as expected, larger ones in Marquesas (justifying the this warning and state of watch). Numerical simulations involving different seismic source models, were used in a later stage to explain the observed tsunami amplitudes.

Reymond, D.; Hebert, H.; Hyvernaud, O.; Allgeyer, S.

2009-12-01

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Tsunami  

Medline Plus

Full Text Available A tsunami is a series of ocean waves generated by sudden displacements in the sea floor, landslides, or volcanic activity. In the deep ocean, the tsunami wave may only be a few inches high. ...

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On the modelling of tsunami generation and tsunami inundation  

CERN Document Server

While the propagation of tsunamis is well understood and well simulated by numerical models, there are still a number of unanswered questions related to the generation of tsunamis or the subsequent inundation. We review some of the basic generation mechanisms as well as their simulation. In particular, we present a simple and computationally inexpensive model that describes the seabed displacement during an underwater earthquake. This model is based on the finite fault solution for the slip distribution under some assumptions on the kinematics of the rupturing process. We also consider an unusual source for tsunami generation: the sinking of a cruise ship. Then we review some aspects of tsunami run-up. In particular, we explain why the first wave of a tsunami is sometimes less devastating than the subsequent waves. A resonance effect can boost the waves that come later. We also look at a particular feature of the 11 March 2011 tsunami in Japan - the formation of macro-scale vortices - and show that these macr...

Dias, Frédéric; O'Brien, Laura; Renzi, Emiliano; Stefanakis, Themistoklis

2012-01-01

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VOLCANIC TSUNAMI GENERATING SOURCE MECHANISMS IN THE EASTERN CARIBBEAN REGION  

Directory of Open Access Journals (Sweden)

Full Text Available Earthquakes, volcanic eruptions, volcanic island flank failures and underwater slides have generated numerous destructive tsunamis in the Caribbean region. Convergent, compressional and collisional tectonic activity caused primarily from the eastward movement of the Caribbean Plate in relation to the North American, Atlantic and South American Plates, is responsible for zones of subduction in the region, the formation of island arcs and the evolution of particular volcanic centers on the overlying plate. The inter-plate tectonic interaction and deformation along these marginal boundaries result in moderate seismic and volcanic events that can generate tsunamis by a number of different mechanisms. The active geo-dynamic processes have created the Lesser Antilles, an arc of small islands with volcanoes characterized by both effusive and explosive activity. Eruption mechanisms of these Caribbean volcanoes are complex and often anomalous. Collapses of lava domes often precede major eruptions, which may vary in intensity from Strombolian to Plinian. Locally catastrophic, short-period tsunami-like waves can be generated directly by lateral, direct or channelized volcanic blast episodes, or in combination with collateral air pressure perturbations, nuéss ardentes, pyroclastic flows, lahars, or cascading debris avalanches. Submarine volcanic caldera collapses can also generate locally destructive tsunami waves. Volcanoes in the Eastern Caribbean Region have unstable flanks. Destructive local tsunamis may be generated from aerial and submarine volcanic edifice mass edifice flank failures, which may be triggered by volcanic episodes, lava dome collapses, or simply by gravitational instabilities. The present report evaluates volcanic mechanisms, resulting flank failure processes and their potential for tsunami generation. More specifically, the report evaluates recent volcanic eruption mechanisms of the Soufriere Hills volcano on Montserrat, of Mt. Pelée on Martinique, of Soufriere on St. Vincent and of the Kick’em Jenny underwater volcano near Grenada and provides an overall risk assessment of tsunami generation from volcanic sources in the Caribbean region.

George Pararas-Carayannis

2004-01-01

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Some events in Central Italy: are they all tsunamis? A revision for the Italian tsunami catalog  

Directory of Open Access Journals (Sweden)

Full Text Available he catalogs available in the literature show that tsunamis affecting Italian coasts are not very strong, except for a few well analyzed events, i.e. the Messina December 28, 1908 tsunami. This study aims at making a careful revision of some minor tsunamigenic events, in particular those occurred along the coasts of the Central Tyrrhenian Sea, considering tsunamis associated with earthquakes, from 1700 to 1919. These events have been poorly studied so far, and need a check to verify their reliability, even though they are reported in the catalogs. The results show how it is difficult to get a clear definition of those tsunamis, because of a gap in the historical sources, in spite of the large amount of seismological data concerning earthquakes related to the anaIyzed tsunamis. This analysis proposes to delete from the catalog some events for which a clear groundlessness appeared.

A. Maramai; A. Tertulliani

1994-01-01

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Detailed analysis of tsunami waveforms generated by the 1946 Aleutian tsunami earthquake  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The 1946 Aleutian earthquake was a typical tsunami earthquake which generated abnormally larger tsunami than expected from its seismic waves. Previously, Johnson and Satake (1997) estimated the fault model of this earthquake using the tsunami waveforms observed at tide gauges. However, they did not ...

Tanioka, Y.; Seno, T.

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Tsunami Research Status in IAEA after Fukushima Event  

International Nuclear Information System (INIS)

On March 11th, 2011, a tremendous earthquake and tsunami occurred on the east coast of Japan. This 9.0 magnitude earthquake was the fifth greatest earthquake ever experienced on the planet. The most remarkable problem was that the Fukishima NPP sites. After Japan earthquake, many international researches about tsunami and earthquake event were started or revised. Especially, the most remarkable point of the great earthquake in east coast of Japan was tsunami event. Before this earthquake, the Niigata earthquake occurred in 2007 and the Kashiwazaki Kariwa nuclear power plant had little damaged. The research about the safety of nuclear power plant against earthquake events was activated by 2007 Niigata earthquake. However, the researches about a tsunami event were very few and only tsunami simulation was only focused. After the Fukushima accident, the international society became very interested in tsunami event as a major external event. Therefore in this study, the tsunami research status in IAEA after Fukushima event and the role of Korea are introduced

2012-01-01

17

Tsunami  

Medline Plus

Full Text Available ... tsunami warnings to the Nation, and a leadership role in tsunami observations and research. Information! New! NOAAWatch ... impacts. Basic information about Tsunamis Tsunami Terminology NOAA's Role NOAA's Tsunami Program 2008–2017 Strategic Plan NOAA's ...

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TSUNAMI AMPLITUDE PREDICTION DURING EVENTS: A TEST BASED ON PREVIOUS TSUNAMIS  

Directory of Open Access Journals (Sweden)

Full Text Available The U.S. West Coast/Alaska Tsunami Warning Center’s (WC/ATWC) far-field tsunami amplitude prediction method is tested by applying the technique to nine previous, well-recorded tsunamigenic events. Predicted tsunami amplitudes outside the source area are shown to be sufficiently accurate to guide warning cancellation/restriction/expansion decisions. Average error per event ranged from 0.04m to 0.29m with error defined as the absolute value of the difference between the recorded amplitude and the predicted amplitude. Had this technique been available during the 1986 Aleutian Is. and the 1994 Kuril Is. tsunami warnings, the warned areas likely would not have been expanded to include the U.S. West Coast, Canada, and Alaska east of Kodiak Island.

Paul M. Whitmore

2003-01-01

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Influence of sedimentary layering on tsunami generation  

CERN Document Server

The present article is devoted to the influence of sediment layers on the process of tsunami generation. The main scope here is to demonstrate and especially quantify the effect of sedimentation on seabed vertical displacements due to an underwater earthquake. The fault is modelled as a Volterra-type dislocation in an elastic half-space. The elastodynamics equations are integrated with a finite element method. A comparison between two cases is performed. The first one corresponds to the classical situation of an elastic homogeneous and isotropic half-space, which is traditionally used for the generation of tsunamis. The second test case takes into account the presence of a sediment layer separating the oceanic column from the hard rock. Some important differences are revealed. The results of the present study may partially explain why the great Sumatra-Andaman earthquake of 26 December 2004 produced such a big tsunami. More precisely, we conjecture that the wave amplitude in the generation region may have bee...

Dutykh, Denys

2008-01-01

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Numerical modelling of historical landslide-generated tsunamis in the French Lesser Antilles  

Directory of Open Access Journals (Sweden)

Full Text Available Two historical landslide-induced tsunamis that reached the coasts of the French Lesser Antilles are studied. First, the Martinique coast was hit by a tsunami down the western flank of Montagne Pelée at the beginning of the big eruption of May 1902. More recently, the northeastern coast of Guadeloupe was affected by a tsunami that had been generated around Montserrat by pyroclastic flows entering the sea, during the July 2003 eruption of the Soufrière Hills volcano. We use a modified version of the GEOWAVE model to compute numerical simulations of both events. Two source hypotheses are considered for each tsunami. The comparison of the simulation results with reported tsunami height data helps to discriminate between the tested source decriptions. In the Martinique case, we obtain a better fit to data when considering three successive lahars entering the sea, as a simplified single source leads to an overstimation of the tsunami wave heights at the coast. In the Montserrat case, the best model uses a unique source which volume corresponds to published data concerning the peak volume flow. These findings emphasize the importance of an accurate description of the relevant volume as well as the timing sequence of the source event in landslide-generated tsunami modelling. They also show that considering far-field effects in addition to near-field effects may significantly improve tsunami modelling.

B. Poisson; R. Pedreros

2010-01-01

 
 
 
 
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Tsunami generation by ocean floor rupture front propagation: Hamiltonian description  

Directory of Open Access Journals (Sweden)

Full Text Available The Hamiltonian method is applied to the problem of tsunami generation caused by a propagating rupture front and deformation of the ocean floor. The method establishes an alternative framework for analyzing the tsunami generation process and produces analytical expressions for the power and directivity of tsunami radiation (in the far-field) for two illustrative cases, with constant and gradually varying speeds of rupture front propagation.

V. I. Pavlov; J. Tromp; E. P. Tito

2009-01-01

22

Tsunami  

Medline Plus

Full Text Available ... and a leadership role in tsunami observations and research. Information! New! NOAAWatch Tsunami website United States East ... the Warning System work? Observations & Data Warnings & Forecasts Research & Modeling More Information: Featured Video! Tsunamis: Know What ...

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Landslide generated tsunamis : numerical modeling and real-time prediction  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Submarine landslides can generate local tsunamis posing a hazard to human lives and coastal facilities. Two major related problems are: (i) quantitative estimation of tsunami hazard and (ii) early detection of the most dangerous landslides. This thesis focuses on both those issues by providing numer...

Brune, Sascha

24

Tsunamis  

Science.gov (United States)

A tsunami is a series of huge ocean waves created by an underwater disturbance. Causes include earthquakes, landslides, volcanic ... space that strike the surface of Earth. A tsunami can move hundreds of miles per hour in ...

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Preliminary Analysis of the Tsunami Generated by the 23 June 2001 Peru Earthquake  

Science.gov (United States)

This animation shows a model of the tsunami generated by the June 23, 2001 Peru earthquake. The first 33 minutes of tsunami propagation are shown. The tsunami is generated very near the coast and propagates outward to the Pacific Basin and along the coastline to the north and south. Largest offshore tsunami amplitudes are in the Chala-Camaná region of southern Peru.

Usgs

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Tsunamis generated by eruptions from mount st. Augustine volcano, alaska.  

UK PubMed Central (United Kingdom)

During an eruption of the Alaskan volcano Mount St. Augustine in the spring of 1986, there was concern about the possibility that a tsunami might be generated by the collapse of a portion of the volcano into the shallow water of Cook Inlet. A similar edifice collapse of the volcano and ensuing sea wave occurred during an eruption in 1883. Other sea waves resulting in great loss of life and property have been generated by the eruption of coastal volcanos around the world. Although Mount St. Augustine remained intact during this eruptive cycle, a possible recurrence of the 1883 events spurred a numerical simulation of the 1883 sea wave. This simulation, which yielded a forecast of potential wave heights and travel times, was based on a method that could be applied generally to other coastal volcanos.

Kienle J; Kowalik Z; Murty TS

1987-06-01

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Tsunamis generated by eruptions from mount st. Augustine volcano, alaska.  

Science.gov (United States)

During an eruption of the Alaskan volcano Mount St. Augustine in the spring of 1986, there was concern about the possibility that a tsunami might be generated by the collapse of a portion of the volcano into the shallow water of Cook Inlet. A similar edifice collapse of the volcano and ensuing sea wave occurred during an eruption in 1883. Other sea waves resulting in great loss of life and property have been generated by the eruption of coastal volcanos around the world. Although Mount St. Augustine remained intact during this eruptive cycle, a possible recurrence of the 1883 events spurred a numerical simulation of the 1883 sea wave. This simulation, which yielded a forecast of potential wave heights and travel times, was based on a method that could be applied generally to other coastal volcanos. PMID:17793232

Kienle, J; Kowalik, Z; Murty, T S

1987-06-12

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Tsunami Generation from the 2004 M=9.2 Sumatra-Andaman Earthquake  

Science.gov (United States)

The pages on this web site (listed in the Table of Contents) provide a brief overview of the tectonic setting and seismological characteristics of the earthquake, as well as a summary of tsunami generation modeling for this event and the March 28, 2005 M=8.6 northern Sumatra earthquake. Supplemental images and diagrams are provided within this collection of pages.

Noaa

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Comparison between three-dimensional linear and nonlinear tsunami generation models  

CERN Document Server

The modeling of tsunami generation is an essential phase in understanding tsunamis. For tsunamis generated by underwater earthquakes, it involves the modeling of the sea bottom motion as well as the resulting motion of the water above it. A comparison between various models for three-dimensional water motion, ranging from linear theory to fully nonlinear theory, is performed. It is found that for most events the linear theory is sufficient. However, in some cases, more sophisticated theories are needed. Moreover, it is shown that the passive approach in which the seafloor deformation is simply translated to the ocean surface is not always equivalent to the active approach in which the bottom motion is taken into account, even if the deformation is supposed to be instantaneous.

Kervella, Y; Dutykh, D; Dias, Fr\\'ed\\'eric; Dutykh, Denys; Kervella, Youen

2006-01-01

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Tsunami generation, propagation, and run-up with a high-order Boussinesq model  

DEFF Research Database (Denmark)

In this work we extend a high-order Boussinesq-type (finite difference) model, capable of simulating waves out to wavenumber times depth kh <25, to include a moving sea-bed, for the simulation of earthquake- and landslide-induced tsunamis. The extension is straight forward, requiring only an additional term within the kinematic bottom condition. As first test cases we simulate linear and nonlinear surface waves generated from both positive and negative impulsive bottom movements. The computed results compare well against earlier theoretical, numerical, and experimental values. Additionally, we show that the long-time (fully nonlinear) evolution of waves resulting from an upthrusted bottom can eventually result in true solitary waves, consistent with theoretical predictions. It is stressed, however, that the nonlinearity used far exceeds that typical of geophysical tsunamis in the open ocean. The Boussinesq-type model is then used to simulate numerous tsunami-type events generated from submerged landslides, inboth one and two horizontal dimensions. The results again compare well against previous experiments and/or numerical simulations. The new extension compliments recently developed run-up capabilities within this approach, and as demonstrated, the model can therefore treat tsunami events from their initial generation, through their later propagation, and final run-up phases. The developed model is shown to maintain reasonable computational efficiency, and is therefore attractive for the simulation of such events, especially in cases where dispersion is important.

Fuhrman, David R.; Madsen, Per A.

2009-01-01

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The 11 March 2011 Tohoku Tsunami Survey in Rikuzentakata and Comparison with Historical Events  

Science.gov (United States)

On 11 March 2011, a moment magnitude M w = 9.0 earthquake occurred off the Japan Tohoku coast causing catastrophic damage and loss of human lives. In the immediate aftermath of the earthquake, we conducted the reconnaissance survey in the city of Rikuzentakata, Japan. In comparison with three previous historical tsunamis impacting the same region, the 2011 event presented the largest values with respect to the tsunami height, the inundation area and the inundation distance. A representative tsunami height of 15 m was recorded in Rikuzentakata, with increased heights of 20 m around rocky headlands. In terms of the inundation area, the 2011 Tohoku tsunami exceeded by almost 2.6 times the area flooded by the 1960 Chilean tsunami, which ranks second among the four events compared. The maximum tsunami inundation distance was 8.1 km along the Kesen River, exceeding the 1933 Showa and 1960 Chilean tsunami inundations by factors of 6.2 and 2.7, respectively. The overland tsunami inundation distance was less than 2 km. The tsunami inundation height linearly decreased along the Kesen River at a rate of approximately 1 m/km. Nevertheless, the measured inland tsunami heights exhibit significant variations on local and regional scales. A designated "tsunami control forest" planted with a cross-shore width of about 200 m along a 2 km stretch of Rikuzentakata coastline was completely overrun and failed to protect the local community during this extreme event. Similarly, many designated tsunami shelters were too low and were overwashed by tsunami waves, thereby failing to provide shelter for evacuees—a risk that had been underestimated.

Liu, Haijiang; Shimozono, Takenori; Takagawa, Tomohiro; Okayasu, Akio; Fritz, Hermann M.; Sato, Shinji; Tajima, Yoshimitsu

2013-06-01

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Current issues on PRA regarding seismic and tsunami events at multiunits and sites based on lessons leaned from Tohoku earthquake/tsunami  

International Nuclear Information System (INIS)

The Tohoku earthquake (Mw9.0) occurred on March 11, 2011 and caused a large tsunami. The Fukushima Dai-ichi NPP (F1-NPP) were overwhelmed by the tsunami and core damage occurred. This paper describes the overview of F1-NPP accident and the usability of tsunami PRA at Tohoku earthquake. The paper makes reference to the following current issues: influence on seismic hazard of gigantic aftershocks and triggered earthquakes, concepts for evaluating core damage frequency considering common cause failure with correlation coefficient against seismic event at multi units and sites, and concepts of 'seismic-tsunami PSA' considering a combination of seismic motion and tsunami effects.

2012-01-01

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GEODYNAMICS OF NAZCA RIDGE’S OBLIQUE SUBDUCTION AND MIGRATION - IMPLICATIONS FOR TSUNAMI GENERATION ALONG CENTRAL AND SOUTHERN PERU: Earthquake and Tsunami of 23 June 2001  

Directory of Open Access Journals (Sweden)

Full Text Available Peru is in a region of considerable geologic and seismic complexity. Thrust faulting along the boundary where the Nazca plate subducts beneath the South American continent has created three distinct seismic zones. The angle of subduction of the Nazca oceanic plate beneath the South American plate is not uniform along the entire segment of the Peru-Chile Trench. Furthermore, subduction is affected by buoyancy forces of the bounding oceanic ridges and fractures - such as the Mendana Fracture Zone (MFZ) to the North and the Nazca Ridge to the South. This narrow zone is characterized by shallow earthquakes that can generate destructive tsunamis of varied intensities. The present study examines the significance of Nazca Ridge’s oblique subduction and migration to the seismicity of Central/Southern Peru and to tsunami generation. The large tsunamigenic earthquake of 23 June 2001 is presented as a case study. This event generated a destructive, local tsunami that struck Peru’s southern coasts with waves ranging from 3 to 4.6 meters (10-15 feet) and inland inundation that ranged from 1 to 3 km. In order to understand the near and far-field tsunamigenic efficiency of events along Central/Southern Peru and the significance of Nazca Ridge’s oblique subduction, the present study examines further the geologic structure of the region and this quake’s moment tensor analysis, energy release, fault rupture and the spatial distribution of aftershocks. Tsunami source mechanism characteristics for this event are presented, as inferred from seismic intensities, energy releases, fault plane solutions and the use of empirical relationships. The study concludes that the segment of subduction and faulting paralleling the Peru-Chile Trench from about 150 to 180 South, as well as the obliquity of convergent tectonic plate collision in this region, may be the reason for shorter rupture lengths of major earthquakes and the generation of only local destructive tsunamis.

George Pararas-Carayannis

2012-01-01

34

THE MAY 17, 1992 EVENT: TSUNAMI AND COASTAL EFFECTS IN EASTERN MINDANAO, PHILIPPINES  

Directory of Open Access Journals (Sweden)

Full Text Available Tsunami invaded the eastern coastlines of Mindanao islands several minutes after the strong ground shaking of the May 17, 1992 quake. Recent field investigations showed that tsunami intensity generally decreases southwards and northwards relative to Bunga and Zaragoza areas. There was an unusually high tsunami wave height (~6m) at Bunga that was most probably due to local site effect. Tsunami waves were generally preceded by the lowering of sea water level while the tsunami arrival times have some variation particularly in Bobon and Panompon. The period of the tsunami wave was quite difficult to determine because of sketchy details and so much variation in terms of the number of waves that attacked the areas investigated.In terms of regional and local geomorphological effects, the 1992 event caused very minor changes. Tsunami sediments were dumped in very few places. It was noted that the coral reefs located between 100-250m from the shore of eastern Mindanao were the coastal features that most probably attenuate the effects tsunami. Local subsidence was likewise observed west of the affected areas.Recommended future activities are tsunami simulations and detailed shore morphology mapping to explain anomalous observations like tsunami intensity, unusual tsunami height and subsidence. Furthermore, considering that there were two large events that occurred during that day less than 30 minutes apart, it is was quite interesting that only one strong ground shaking was observed by local inhabitants. Thus, it is highly recommended that a closer look into the seismic data would be undertaken to explain such anomaly.

Glenda M. Besana; Masataka Ando; Ma. Hannah Mirabueno

2004-01-01

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Catalogue of tsunamis generated in Italy and in Côte d'Azur, France: a step towards a unified catalogue of tsunamis in Europe  

Directory of Open Access Journals (Sweden)

Full Text Available This work presents a catalogue of the tsunamis generated in the seas watering the Italian coasts, including the neighbouring area of Côte d'Azur (France). Events generated far from Italy and affecting the Italian coasts are not taken into account here. The catalogue, that we will also call the Quick-Look Catalog (QLC), is organised in three main sections that are named the Quick-Look Table, the Quick-Look Accounts File and the References File, having the respective abbreviations of QLT, QLAF and RF. The QLT is a synoptic table containing the relevant information available for each event, one table row corresponding to one event. More details are provided in the QLAF, where each event is dedicated a specific subsection: here the description of the tsunami includes all essential aspects that are suitably referenced and is preceded by a concise report concerning the tsunami cause. Lastly, the RF is the list of all the papers and publications quoted in the QLT and QLAF. Notice that efforts have been made to qualify each event by means of contemporaneous sources, although later sources and indirect sources, such as existing catalogues, have not been disregarded. Besides, specific recent studies on the events have been given special mention. In this work some general review of the past catalogues of tsunamis and of recent trends in the subject are expressed. Particularly, great attention is given to analysing the CFB of the Italian tsunamis due to Caputo and his collaborators (Caputo and Faita, 1984; Bedosti and Caputo, 1986), the acronym being formed by the ordered initials of the authors. Motivations clarifying the need for a new catalogue of the Italian tsunamis are illustrated circumstantially. The very different philosophies that are at the basis of the CFB and of the present QLC lead to quite diverse products and results, that are summarised by a table where the events included in the CFB and in the QLC are compared: the net effect of the rigorous scrutiny applied to the sources and of the coherent analysis applied to the data is that only 67 events are included in the QLC, which is about one third of the events that can be counted in the CFB.

S. Tinti; A. Maramai

1996-01-01

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ASSESSMENT OF POTENTIAL TSUNAMI GENERATION IN CHINA'S BOHAI SEA FROM DIRECT GEOTECTONIC AND COLLATERAL SOURCE MECHANISMS  

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Full Text Available The Bohai Sea borders northeastern China's most populous and highest economic valuecoastal areas where several megacities are located. Critical infrastructure facilities exist or areunder construction, including a nuclear power plant and super port facilities. Large reserves of oilhave been discovered and a number of offshore oil platforms have been built. The extent ofdevelopment along coastal areas requires a better assessment of potential tsunami risks. Althoughtsunamis do not pose as much of a threat as earthquakes in this region, locally destructive tsunamishave been generated in the past and future events could have significant impacts on coastalpopulations and China's economy, particularly because most of the development has taken place inlow-lying regions, including river deltas. The present study examines the geotectonics of the Bohaibasin region, the impact of past historical events, and the potential for local tsunami generationfrom a variety of direct and collateral source mechanisms triggered by intra plate earthquakes.More specifically, the present study examines: a)major active faults bounding the Bohai Basin; b)the resulting crustal deformation patterns of tectonic structures that have resulted in catastrophicearthquakes in recent years; c) the basin-wide extension - with local inversion - extending into theBohai Sea that generated tsunamigenic earthquakes in 1888 and 1969; and d) deformational futureseismic events with the potential to generate local tsunamis directly or by collateral mechanisms offolding, en-echelon bookshelf failures, or from destabilization/dissociation of structuralaccumulations of gas hydrate deposits within the basin's thick sedimentary stratigraphic layers.

G. Pararas Carayannis

2009-01-01

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Characteristic Tsunami Events in the Area of Rhodes Island, East Hellenic Arc  

Science.gov (United States)

The eastern segment of the Hellenic arc-trench (EHAT) is one of the most active in the Mediterranean region producing both large earthquakes and tsunamis. Therefore, it was selected as the master test-site of the EU TRANSFER tsunami research project. Previous research results indicates that EHAT produces characteristic shallow earthquakes of M¡Ö7.2. From historical documentary sources and instrumental records we conclude that in the last six centuries six characteristic earthquakes ruptured the EHAT: 1481, 1609, 1741, 1851, 1957. This implies that EHAT is ruptured by strong, shallow shocks as an average every 120±13 years, indicating a quasi- periodic than random process. However, the tsunami generation deviates from such a quasi-periodic pattern given that only the 1481, 1609 and 1741 earthquakes produced strong tsunamis, while the 1851 shock generated only a small-to-moderate local tsunami and the 1957 one was non-tsunamigenic. We introduce the concept of ¡°characteristic tsunami¡± to describe similar, strong tsunamis produced by earthquakes occurring in the same fault segment. Then, we conclude that only some characteristics earthquakes produce characteristic tsunamis while others do not. From the point of view of tsunami hazard assessment it is of great importance to estimate the probability that the next characteristic earthquake may generate a characteristic tsunami. To this goal we apply a conditional probabilitiy procedure tested recently in highly tsunamigenic zones of the Pacific Ocean.This is a contribution of the EU Research Project "TRANSFER", contract N.037058, FP6-2005-Global-4, Reduction of Tsunami Risks.

Fokaefs, A.; Daskalaki, E.; Orfanogiannaki, K.; Papadopoulos, G. A.

2007-12-01

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TSUNAMIS OF THE ARABIAN PENINSULA A GUIDE OF HISTORIC EVENTS  

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Full Text Available The Arabian Peninsula has been affected by tsunamis in the past. The Peninsula is bounded by the Persian Gulf on its northeast side, the Red Sea on its west side, and the Arabian Sea, the Gulf of Aden, and the Indian Ocean to its east and south. Each of these areas is very different geographically, tectonically, and bathymetrically.Only two, localized tsunamis have been recorded in the Red Sea and one, doubtful, tsunami in the Persian Gulf. Almost all of the recorded tsunamis along the Arabian Peninsula have occurred on its eastern and southern edge, some, such as the one formed by the 1945 Makran earthquake, were extremely destructive. The Indian Ocean is the most likely source area for future destructive tsunamis that would impact the Arabian Peninsula.

Benjamin R. Jordan

2008-01-01

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Numerical simulation of the tsunami generated by a past catastrophic landslide on the volcanic island of Ischia, Italy  

Science.gov (United States)

The island of Ischia, Gulf of Naples, Italy, like many other volcanic islands is affected by mass failures, that are mainly related to secondary volcanic processes such as slope steepening and seismic shaking. The block resurgence of its main relief, Mount Epomeo, has been recognised to contribute cyclically to mass instability and cause landslides, that occasionally may reach the sea and start tsunamis. In this work we explore the consequences of the Ischia Debris Avalanche (IDA), a flank collapse that occurred in historical times, and involved the whole Mount Epomeo edifice including its submarine portion, and that may have caused gigantic sea waves affecting all the coasts of Ischia and of the Gulf of Naples. The IDA and the generated tsunami have been taken as the worst-case scenario for the occurrence of a new tsunami in the area. They have been simulated through numerical codes developed and maintained by the University of Bologna. The simulation shows that the IDA-induced tsunami attacks severely all the coasts of the Gulf of Naples with the highest waves obtained for the island of Ischia, the island of Capri and the peninsula of Sorrento. The propagation pattern of the IDA tsunami can be used to get hints on the impact that such an event may have had on early populations habiting Gulf of Naples, but also to get clues on the area that could be most severely hit by a tsunami generated by a smaller-scale landslide that may occur in the same source zone.

Tinti, Stefano; Chiocci, Francesco Latino; Zaniboni, Filippo; Pagnoni, Gianluca; de Alteriis, Giovanni

2011-03-01

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Tsunami simulations for historical and plausible mega-thrust events originating in the Eastern Mediterranean Sea  

Science.gov (United States)

Tsunamis have been reported at rates of one to two per year in the Mediterranean Sea, on average, over the past 2000 years (Ambraseys and Synolakis, 2010). However, quantification of tsunami hazards in the Eastern Mediterranean Sea remains difficult, as large events are infrequent. Simulations were performed for a series of seismic events originating along the Eastern Hellenic Arc and Western Cyprian Arc. The locations and source characteristics represent plausible mega-thrust events similar to historical events along the Hellenic Arc, including the 365 AD and 1303 AD events. Sensitivity simulations were performed to address uncertainty in the location and source characteristics of the 1303 AD event, and in consideration of potential future events originating along the Eastern Hellenic Arc. Sensitivity simulations were also performed for events originating along the Western Cyprian Arc. The hydrodynamic simulations used a series of codes known as the Method of Splitting Tsunami (MOST) (Titov and Synolakis, 1998). Reported results include wave propagation in the Eastern Mediterranean and tsunami inundation near Alexandria, Egypt, and for neighboring coastlines. References: Ambraseys, N. and C.E. Synolakis (2010), Tsunami Catalogs for the Eastern Mediterranean, Revisited, Journal of Earthquake Engineering 14(3): 309-330; and Titov V.V. and C.E. Synolakis (1998), 'Numerical modeling of tidal wave runup,' J. Waterw. Port Coast. Ocean Eng. 124(4): 157-171.

Valle, Brett; Kalligeris, Nikos; Findikakis, Angelos; Okal, Emile; Synolakis, Costas

2013-04-01

 
 
 
 
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An approximate method of short-term tsunami forecast and the hindcasting of some recent events  

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Full Text Available The paper presents a method for a short-term tsunami forecast based on sea level data from remote sites. This method is based on Green's function for the wave equation possessing the fundamental property of symmetry. This property is well known in acoustics and seismology as the reciprocity principle. Some applications of this principle on tsunami research are considered in the current study. Simple relationships and estimated transfer functions enabled us to simulate tsunami waveforms for any selected oceanic point based only on the source location and sea level data from a remote reference site. The important advantage of this method is that it is irrespective of the actual source mechanism (seismic, submarine landslide or other phenomena). The method was successfully applied to hindcast several recent tsunamis observed in the Northwest Pacific. The locations of the earthquake epicenters and the tsunami records from one of the NOAA DART sites were used as inputs for the modelling, while tsunami observations at other DART sites were used to verify the model. Tsunami waveforms for the 2006, 2007 and 2009 earthquake events near Simushir Island were simulated and found to be in good agreement with the observations. The correlation coefficients between the predicted and observed tsunami waveforms were from 0.50 to 0.85. Thus, the proposed method can be effectively used to simulate tsunami waveforms for the entire ocean and also for both regional and local tsunami warning services, assuming that they have access to the real-time sea level data from DART stations.

Yu. P. Korolev

2011-01-01

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Tsunami survey expedition: preliminary investigation of Maldivian coral reefs two weeks after the event.  

UK PubMed Central (United Kingdom)

On December 26th 2004, a earthquake west of Sumatra generated a devastating tsunami. Hundreds of thousands of people fell victim. Economic losses were greatest in those countries dependant on tourism. The impact in the Maldives on persons and things was modest. Immediately following the event and notwithstanding the lack of scientific data, the mass media gave catastrophic reports on the state of coral reefs in the area. This paper reports on the first survey on coral reefs in the Maldives after the Tsunami. Ocean walls, passes, inner reefs, and shoals in the North and South Malé atolls, were surveyed two weeks after the event. Significant damage was recorded in the passes in the South Malé atoll. Our observations showed that the damage was more or less extensive depending on latitude and topography. Sri Lanka may have broken the wave's rush, reducing the extent of the impact on northern atolls. The water's acceleration inside the passes was so intense as to cause reef collapses. The observed damage represents a minimum fraction of the entire coral reef system. Tourist perception of the area seems unchanged. These data may be used to disseminate correct information about the state of Maldives coral reefs, which would be useful in relaunching local economy.

Goffredo S; Piccinetti C; Zaccanti F

2007-08-01

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Tsunami hazard in La Réunion island from numerical modeling of historical events  

Science.gov (United States)

Whereas major tsunamis have recently affected the southwest Indian Ocean, tsunami hazard in this basin has never been thoroughly examined. Our study contributes to fill in this lack and focuses on La Réunion island for which tsunami hazard related to great earthquakes is evaluated by modeling the scenarios of major historical events. Then, our numerical modeling allow us to compare the tsunami impact at regional scale according to the seismic sources; we thus identify earthquakes locations which most affect the island and describe the impact distribution along its coastline. Thirdly, detailed models are performed for selected sites based on high resolution bathymetric and topographic data; they provide estimations of the water currents, wave heights and potential inundations. When available, field measurements and tide records allow testing our models. Arrival time, amplitude of the first wave and impact on the tide gauge time series are well reproduced. Models are consistent with the observations. The west coast of La Réunion is the most affected (to 2.7 m in the harbour of Le Port Est for 2004 event) by transoceanic tsunamis. Numerical modeling has been performed at Saint-Paul for the 2004 Sumatra-Andaman event and 1833 Sumatra event; the low topography of this town could make it vulnerable to tsunami waves. Harbours, particularly prone to undergo significant damages, are also examined. Outside the harbours as well as at Saint-Paul, inundations are predicted along the coastline due to important local wave heights (> 2.5 m).

Quentel, E.; Loevenbruck, A.; Hébert, H.; Allgeyer, S.

2013-05-01

44

Tsunami Database  

Science.gov (United States)

The Tsunami Database is a global digital database containing information on more than 2000 tsunamis maintained by the National Geophysical Data Center. This is an interactive site; the user is asked to enter search parameters such as date, latitude and longitude, cause of the tsunami - earthquake, landslide, volcano, or all combined - magnitude, and death. Information is then generated on tsunamis that match that data. The National Geophysical Data Center also maintains an historic slide set collection of tsunami damage.

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The 30 December 2002 landslide-induced tsunamis in Stromboli: sequence of the events reconstructed from the eyewitness accounts  

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Full Text Available On 30 December 2002 the coast of the volcanic island of Stromboli, in the Tyrrhenian sea, Italy, was attacked by two tsunamis generated by landslides that took place on the north-west flank of the volcano. The landslides and the tsunamis represented the most impressive and threatening episodes of a strong effusive eruption, started on 28 December from a new vent which opened close to the north-east crater of the volcano. In spite of the intensified monitoring carried out in response to the eruption, the landslides and the ensuing tsunamis were not foreseen, and the available instrumental data are insufficient to allow a precise reconstruction of the sequence of the events. The seismic network recorded two main landslides along the steep slope of Sciara del Fuoco, with onset around 13:15 and 13:23 local time (GMT+1). The tsunamis were the direct consequence of the mass movements. Three main post-event surveys helped make assessment on the wave impact on the coast. In this paper the attention is focussed on the accounts of the eye-witnesses, that help us clarify and understand what happened. People in the source area (Sciara del Fuoco) reported a small-volume subaerial slide taking place first, then a sharp cut forming in the sea water down to the sea floor (about 10–20 m deep) and propagating almost parallel to the coastline, be concomitantly associated with a sea retreat and a subsequent sea advance. It is suggested here that the cut was the effect of a large submarine landslide that detached from very close to the coast and produced the 13:15 signal in the recorded seismograms. The second, mostly subaerial, slump was observed to slide down 7–8 min later and to excite a train of waves some distance offshore. Not all the witnesses realised that two distinct tsunamis occurred. The tsunami period was probably in the order of 100 s, but shorter period crests were seen to travel on the top of the long-period waves by several persons. The duration of each tsunami was appreciated to be around 5–7 min. It is difficult to ascertain which tsunami was the largest, since there is no full agreement among the observers, but certainly by accounts both were characterised by large destructive waves.

S. Tinti; A. Manucci; G. Pagnoni; A. Armigliato; F. Zaniboni

2005-01-01

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Tsunami wave generation by the eruption of underwater volcano  

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Full Text Available Eruption of volcanoes represents one of important origins of tsunami waves and is responsible for most catastrophic tsunami (Krakatau, 1883; Thira, BC). The products of volcano eruption include solids, liquids (lava) and gases. The present article presents hydrodynamic model of relatively slow process of eruption, with domination of liquids. The process of underwater eruption of lava causes the disturbance of ocean free surface. The standard formulation of hydrodynamic problem for incompressible fluid in cylindrically symmetric layer of with rigid bottom and free surface with local hydrodynamic source (volcano) is used. This problem is solved by constructing Green function using methodology of Sretenskij. The solution is obtained in the form of an integral and depends on the dynamics of eruption. Real data show that some volcanoes can erupt several millions of tons of lava during several dozens of seconds (Bezimjannij, Kamchatka). The long waves are more efficiently generated by larger T: these tsunamis can have smaller initial perturbations of free surface, but the waves are long and can transmit their energy over longer distances.

Y. Egorov

2007-01-01

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Numerical simulation of tsunami waves generated by deformable submarine landslides  

Science.gov (United States)

This paper presents a new submarine landslide model based on the non-hydrostatic wave model NHWAVE of Ma et al. (2012). The landslide is modeled as a water-sediment mixture. The dense plume is driven by baroclinic pressure forcing introduced by spatial density variations. The model is validated using laboratory measurements of turbidity currents and of water wave generation by a granular landslide. The model is then utilized to study the dependence of landslide motion and associated tsunami wave generation on parameters including sediment settling velocity, initial depth of the landslide and slide density. Model results show that the slide motion and water waves which it generates are both sensitive to these parameters. The relative tsunamigenic response to rigid and deformable landslides of equal initial geometry and density is also examined. It is found that the wave energy is mostly concentrated on a narrow band of the dominant slide direction for the waves generated by rigid landslides, while directional spreading is more significant for waves generated by deformable landslides. The deformable landslide has larger speed and acceleration at the early stage of landslide, resulting in larger surface waves. The numerical results indicate that the model is capable of reasonably simulating tsunami wave generation by submarine landslides.

Ma, Gangfeng; Kirby, James T.; Shi, Fengyan

2013-09-01

48

Differences in tsunami generation between the December 26, 2004 and March 28, 2005 Sumatra earthquakes  

Science.gov (United States)

Source parameters affecting tsunami generation and propagation for the Mw > 9.0 December 26, 2004 and the Mw = 8.6 March 28, 2005 earthquakes are examined to explain the dramatic difference in tsunami observations. We evaluate both scalar measures (seismic moment, maximum slip, potential energy) and finite-source representations (distributed slip and far-field beaming from finite source dimensions) of tsunami generation potential. There exists significant variability in local tsunami runup with respect to the most readily available measure, seismic moment. The local tsunami intensity for the December 2004 earthquake is similar to other tsunamigenic earthquakes of comparable magnitude. In contrast, the March 2005 local tsunami was deficient relative to its earthquake magnitude. Tsunami potential energy calculations more accurately reflect the difference in tsunami severity, although these calculations are dependent on knowledge of the slip distribution and therefore difficult to implement in a real-time system. A significant factor affecting tsunami generation unaccounted for in these scalar measures is the location of regions of seafloor displacement relative to the overlying water depth. The deficiency of the March 2005 tsunami seems to be related to concentration of slip in the down-dip part of the rupture zone and the fact that a substantial portion of the vertical displacement field occurred in shallow water or on land. The comparison of the December 2004 and March 2005 Sumatra earthquakes presented in this study is analogous to previous studies comparing the 1952 and 2003 Tokachi-Oki earthquakes and tsunamis, in terms of the effect slip distribution has on local tsunamis. Results from these studies indicate the difficulty in rapidly assessing local tsunami runup from magnitude and epicentral location information alone. Copyright ?? The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences; TERRAPUB.

Geist, E. L.; Bilek, S. L.; Arcas, D.; Titov, V. V.

2006-01-01

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Boussinesq systems in two space dimensions over a variable bottom for the generation and propagation of tsunami waves  

CERN Multimedia

Considered here are Boussinesq systems of equations of surface water wave theory over a variable bottom. A simplified such Boussinesq system is derived and solved numerically by the standard Galerkin-finite element method. We study by numerical means the generation of tsunami waves due to bottom deformation and we compare the results with analytical solutions of the linearized Euler equations. Moreover, we study tsunami wave propagation in the case of the Java 2006 event, comparing the results of the Boussinesq model with those produced by the finite difference code MOST, that solves the shallow water wave equations.

Mitsotakis, Dimitrios

2009-01-01

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Advanced Geospatial Hydrodynamic Signals Analysis for Tsunami Event Detection and Warning  

Science.gov (United States)

Current early tsunami warning can be issued upon the detection of a seismic event which may occur at a given location offshore. This also provides an opportunity to predict the tsunami wave propagation and run-ups at potentially affected coastal zones by selecting the best matching seismic event from a database of pre-computed tsunami scenarios. Nevertheless, it remains difficult and challenging to obtain the rupture parameters of the tsunamigenic earthquakes in real time and simulate the tsunami propagation with high accuracy. In this study, we propose a supporting approach, in which the hydrodynamic signal is systematically analysed for traces of a tsunamigenic signal. The combination of relatively low amplitudes of a tsunami signal at deep waters and the frequent occurrence of background signals and noise contributes to a generally low signal to noise ratio for the tsunami signal; which in turn makes the detection of this signal difficult. In order to improve the accuracy and confidence of detection, a re-identification framework in which a tsunamigenic signal is detected via the scan of a network of hydrodynamic stations with water level sensing is performed. The aim is to attempt the re-identification of the same signatures as the tsunami wave spatially propagates through the hydrodynamic stations sensing network. The re-identification of the tsunamigenic signal is technically possible since the tsunami signal at the open ocean itself conserves its birthmarks relating it to the source event. As well as supporting the initial detection and improving the confidence of detection, a re-identified signal is indicative of the spatial range of the signal, and thereby it can be used to facilitate the identification of certain background signals such as wind waves which do not have as large a spatial reach as tsunamis. In this paper, the proposed methodology for the automatic detection of tsunamigenic signals has been achieved using open data from NOAA with a recorded tsunami event in the Pacific Ocean. The new approach will be tested in the future on other oceanic regions including the Mediteranean Sea and North East Atlantic Ocean zones. Both authors acknowledge that the current research is currently conducted under the TRIDEC IP FP7 project[1] which involves the development of a system of systems for collaborative, complex and critical decision-support in evolving crises. [1] TRIDEC IP ICT-2009.4.3 Intelligent Information Management Project Reference: 258723. http://www.tridec-online.eu/home

Arbab-Zavar, Banafshe; Sabeur, Zoheir

2013-04-01

51

Identification of elements at risk for a credible tsunami event for Istanbul  

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Full Text Available Physical and social elements at risk are identified for a credible tsunami event for Istanbul. For this purpose, inundation maps resulting from probabilistic tsunami hazard analysis for a 10% probability of exceedance in 50 yr are utilised in combination with the geo-coded inventories of building stock, lifeline systems and demographic data. The built environment on Istanbul's shorelines that is exposed to tsunami inundation comprises residential, commercial, industrial, public (governmental/municipal, schools, hospitals, sports and religious), infrastructure (car parks, garages, fuel stations, electricity transformer buildings) and military buildings, as well as piers and ports, gas tanks and stations and other urban elements (e.g., recreational facilities). Along the Marmara Sea shore, Tuzla shipyards and important port and petrochemical facilities at Ambarl? are expected to be exposed to tsunami hazard. Significant lifeline systems of the city of Istanbul such as natural gas, electricity, telecommunication and sanitary and waste-water transmission, are also under the threat of tsunamis. In terms of social risk, it is estimated that there are about 32 000 inhabitants exposed to tsunami hazard.

U. Hancilar

2012-01-01

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Introduction to "Historical and Recent Catastrophic Tsunamis in the World: Volume I. The 2011 Tohoku Tsunami"  

Science.gov (United States)

Twenty-one papers on the 2011 Tohoku, Japan tsunami are included in Volume I of the PAGEOPH topical issue "Historical and Recent Catastrophic Tsunamis in the World." Two papers discuss seismological aspects of the event with an emphasis on tsunami generation and warning. Five papers report the impacts and effects in Japan through field surveys of tsunami heights, building damage, and tsunami deposits or analysis of satellite data. Eight papers report the tsunami effects on other Pacific coasts, including the Kuril Islands, the USA, French Polynesia, the Galapagos Islands, Australia, and New Zealand. Three papers report on analyses of the instrumental records of the 2011 Tohoku tsunami, and two more papers report their modelling efforts of the tsunami. Several of the above papers also compare the 2011 Tohoku and 2010 Chile tsunamis.

Satake, Kenji; Rabinovich, Alexander B.; Dominey-Howes, Dale; Borrero, José C.

2013-06-01

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The human impact of tsunamis: a historical review of events 1900-2009 and systematic literature review.  

Science.gov (United States)

Introduction. Although rare, tsunamis have the potential to cause considerable loss of life and injury as well as widespread damage to the natural and built environments. The objectives of this review were to describe the impact of tsunamis on human populations in terms of mortality, injury, and displacement and, to the extent possible, identify risk factors associated with these outcomes. This is one of five reviews on the human impact of natural disasters. Methods. Data on the impact of tsunamis were compiled using two methods, a historical review from 1900 to mid 2009 of tsunami events from multiple databases and a systematic literature review to October 2012 of publications. Analysis included descriptive statistics and bivariate tests for associations between tsunami mortality and characteristics using STATA 11. Findings. There were 255,195 deaths (range 252,619-275,784) and 48,462 injuries (range 45,466-51,457) as a result of tsunamis from 1900 to 2009. The majority of deaths (89%) and injuries reported during this time period were attributed to a single event -the 2004 Indian Ocean tsunami. Findings from the systematic literature review indicate that the primary cause of tsunami-related mortality is drowning, and that females, children and the elderly are at increased mortality risk. The few studies that reported on tsunami-related injury suggest that males and young adults are at increased injury-risk. Conclusions. Early warning systems may help mitigate tsunami-related loss of life. PMID:23857277

Doocy, Shannon; Daniels, Amy; Dick, Anna; Kirsch, Thomas D

2013-04-16

54

The human impact of tsunamis: a historical review of events 1900-2009 and systematic literature review.  

UK PubMed Central (United Kingdom)

Introduction. Although rare, tsunamis have the potential to cause considerable loss of life and injury as well as widespread damage to the natural and built environments. The objectives of this review were to describe the impact of tsunamis on human populations in terms of mortality, injury, and displacement and, to the extent possible, identify risk factors associated with these outcomes. This is one of five reviews on the human impact of natural disasters. Methods. Data on the impact of tsunamis were compiled using two methods, a historical review from 1900 to mid 2009 of tsunami events from multiple databases and a systematic literature review to October 2012 of publications. Analysis included descriptive statistics and bivariate tests for associations between tsunami mortality and characteristics using STATA 11. Findings. There were 255,195 deaths (range 252,619-275,784) and 48,462 injuries (range 45,466-51,457) as a result of tsunamis from 1900 to 2009. The majority of deaths (89%) and injuries reported during this time period were attributed to a single event -the 2004 Indian Ocean tsunami. Findings from the systematic literature review indicate that the primary cause of tsunami-related mortality is drowning, and that females, children and the elderly are at increased mortality risk. The few studies that reported on tsunami-related injury suggest that males and young adults are at increased injury-risk. Conclusions. Early warning systems may help mitigate tsunami-related loss of life.

Doocy S; Daniels A; Dick A; Kirsch TD

2013-01-01

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Monte Carlo Event Generators  

Energy Technology Data Exchange (ETDEWEB)

We describe progress in the development of Monte Carlo event generators for the full simulation of collider physics events on the hadron level. We briefly comment on all areas of simulation but focus on the matching of higher order perturbative matrix elements and developments in multiple partonic interaction models.

Gieseke, Stefan, E-mail: stefan.gieseke@kit.edu [Institut fuer Theoretische Physik, Karlsruhe Institute of Technology, 76128 Karlsruhe (Germany)

2012-01-15

56

Recent Tsunamis That Affected the Japanese Coasts and Evaluation of JMA's Tsunami Warnings  

Science.gov (United States)

During the last two years (Sep 2006 to Aug 2008), Japan Meteorological Agency (JMA) issued tsunami advisories or warnings for eight events. Tsunami estimations in the advisories or warnings are considered appropriate for six cases. No tsunami was confirmed for the other two cases, one of which was thought to be a quite peculiar case. The November 2006 and January 2007 Kuril earthquakes, for which tsunami warnings were issued on the Hokkaido coasts, impelled JMA to improve its methods in estimating tsunamis. The JMA magnitude (M) was larger for the 2007 earthquake than the 2006 event, but other magnitude scales as well as the observed tsunamis were smaller (Fujii and Satake, 2008, BSSA). The long duration of these Kuril tsunamis were due to reflected wave at Emperor seamount chain (Koshimura et al., 2007, GRL). These features have become to be considered in the current JMA's system. The Noto-hanto earthquake (M 6.9) on March 25 in 2007 generated a small (Rumoi does not match with the numerical simulation, hence considered as meteorological origin. On August 16, for the great earthquake (Mw 8.0) off Peru coast, JMA issued tsunami advisory, based on the tsunami numerical simulation and actual tsunami data in Hawaii. The tsunami heights recorded on tide gauges were 0.2 m or less in Japan. On May 8, 2008, an earthquake off Ibaraki (M 7.0) occurred and JMA did not issue tsunami advisory. Instead, JMA issued a tsunami forecast, which informed that the maximum tsunami height would be below 0.2m and that such tsunami would not cause damage. Some tide stations recorded very weak tsunami, around 0.1m. On July 19, an earthquake (M 6.6) off Fukushima prefecture caused tsunami up to 0.2 m. JMA issued tsunami advisory for this event.

Satake, K.; Hasegawa, Y.; Nishimae, Y.; Igarashi, Y.

2008-12-01

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A nested-grid Boussinesq-type approach to modelling dispersive propagation and runup of landslide-generated tsunamis  

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Full Text Available A tsunami generated by large-volume landslide can propagate across the ocean and flood communities around the basin. The evolution of landslide-generated tsunamis is affected by the effects of frequency dispersion and involves processes of different temporal and spacial scales. In this paper, we develop a numerical approach employing the weakly nonlinear and fully nonlinear Boussinesq-type theories and nested computational grids. The propagation in a large domain is simulated with the weakly nonlinear model in a geographical reference frame. The nearshore wave evolution and runup are computed with the fully nonlinear model. Nested grids are employed to zoom simulations from larger to smaller domains at successively increasing resolutions. The models and the nesting scheme are validated for theoretical analysis, laboratory experiments and a historical tsunami event. By applying this approach, we also investigate the potential tsunami impact on the US east coast due to the possible landslide on La Palma Island. The scenario employed in this study represents an event of extremely low probability.

H. Zhou; C. W. Moore; Y. Wei; V. V. Titov

2011-01-01

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Numerical investigations of tsunamis generated by pyroclastic flows from the Kikai caldera, Japan  

Science.gov (United States)

Tsunamis generated by a voluminous pyroclastic flow entering the sea during a caldera-forming eruption at the Kikai caldera, Japan, were investigated by using a two-layer shallow water model which is limited to the source conditions and their impact on coastal areas. Volume flux of the dense component of the pyroclastic flow was controlled by a sine function. Results showed that the maximum height of the tsunami was largest in models with the largest volume flux of the flows. The approximate source conditions of the tsunami, which can stir sediment particles on the sea floor, were investigated using the non-dimensional boundary shear stress. Results from our simulation showed that the shear stress to initiate movement of sediment particles was not easily achieved in areas where there was evidence of a tsunami. A caldera collapse is thought more likely to have generated the huge tsunami rather than a pyroclastic flow.

Maeno, Fukashi; Imamura, Fumihiko

2007-12-01

59

QCD (and) event generators  

International Nuclear Information System (INIS)

Recent developments in QCD phenomenology have spurred on several improved approaches to Monte Carlo event generation, relative to the post-LEP state of the art. In this brief review, the emphasis is placed on approaches for (1) consistently merging fixed-order matrix element calculations with parton shower descriptions of QCD radiation, (2) improving the parton shower algorithms themselves, and (3) improving the description of the underlying event in hadron collisions.

2005-05-01

60

Tsunamis and Tsunami Research  

Science.gov (United States)

This site features information about tsunamis and tsunami research at the Institute of Ocean Sciences (IOS) of Canada's Department of Fisheries and Oceans. There is introductory information on tsunamis and what they are, accounts of some historically significant events, and a discussion of the Cascadia Subduction Zone, the likely source for earthquakes and tsunamis in coastal British Columbia. The homepage provides contact information for IOS personnel and a list of recent publications in downloadable format (PDF). The data page provides access to archived and real-time data from moored instruments, satellites, lighthouses, buoys, and other sources. The research page features links to projects grouped by topic (the Arctic, coastal oceanography, the open ocean, and others). There is also an extensive list of older publications (1994-2006), some of which are downloadable, and links to news items and event announcements.

 
 
 
 
61

Prediction of Tsunami Waves and Runup Generated by 3d Granular Landslides  

Science.gov (United States)

Subaerial and submarine landslides can trigger tsunamis with locally high amplitudes and runup, which can cause devastating effects in the near field region. The 50th anniversary of the Lituya Bay 1958 landslide impact generated mega tsunami recalls the largest tsunami runup of 524m in recorded history. In contrast to earthquake generated tsunamis, landslide generated tsunami sources are not confined to active tectonic regions and therefore are of particular importance for the Atlantic Ocean. Landslide generated tsunamis were studied in the three dimensional NEES tsunami wave basin TWB at OSU based on the generalized Froude similarity. A novel pneumatic landslide generator was deployed to control the landslide geometry and kinematics. Granular materials were used to model deformable landslides. Measurement techniques such as particle image velocimetry (PIV), multiple above and underwater video cameras, multiple acoustic transducer arrays (MTA), as well as resistance wave and runup gauges were applied. The wave generation was characterized by an extremely unsteady three phase flow consisting of the slide granulate, water and air entrained into the flow. The underwater cameras and the MTA provide data on the landslide deformation as it impacts the water surface, penetrates the water and finally deposits on the bottom of the basin. The influence of the landslide volume, shape and the impact speed on the generated tsunami wave characteristics were extensively studied. The experimental data provides prediction models for the generated tsunami wave characteristics based on the initial landslide characteristics and the final slide deposits. PIV provided instantaneous surface velocity vector fields, which gave insight into the kinematics of the landslide and wave generation process. At high impact velocities flow separation occurred on the slide shoulder resulting in a hydrodynamic impact crater. The recorded wave profiles yielded information on the wave propagation and attenuation. The measured wave speed of the leading wave corresponds well to the theoretical approximation of the solitary wave speed while the trailing waves are considerably slower in nature. Attenuation functions of the leading wave crest amplitude, the wave length and the time period were obtained to study the wave behavior in the near field and far field regions. The experimental data also provided the energy conversion rate between the landslide source and the generated tsunami waves. The slide characteristics measured in the experiment provides the landslide source for numerically modeling these landslide tsunamis. The measured wave data serves the validation and advancement of 3-dimensional numerical landslide tsunami and prediction models.

Mohammed, F.; Fritz, H. M.

2008-12-01

62

Catalogue of reported tsunami events in the Adriatic Sea (from 58 B.C. to 1979 A.D.)  

International Nuclear Information System (INIS)

This catalogue furnishes a collection of the reported tsunamis within the Adriatic, i.e. Italian coasts from the Strait of Otranto to the gulf of Trieste, the coasts of Slovenia, Croatia, Serbia, Montenegro and Albania. The events are obtained by the cross-comparison between many existing catalogues, in order to extract all the available reported ones. For each tsunamigenic event, when available in a catalogue, we report: origin time, location, macroseismic intensity, magnitude and the areas (within Adriatic basin) where tsunamis have been reported. In the last column of the table, all the catalogues in which some information of the event (earthquake and tsunami) has been found, are listed; bold letters indicate the basic catalogue for that event (i.e. the catalogue where the origin time has been taken from). Since in the present catalogue more attention is paid to the tsunamis than to the seismic events, the bold reference indicates always the tsunami-catalogue, and not the seismic ones, when contemporarily available. For some events there are no records of a related tsunami (they are labelled as N.A.T.R.= not available tsunami report) but they are included since their location and magnitude suggest a tsunamigenic potential. (author)

2005-01-01

63

Evaluation of tsunami risk in the Lesser Antilles  

Directory of Open Access Journals (Sweden)

Full Text Available The main goal of this study is to give the preliminary estimates of the tsunami risks for the Lesser Antilles. We investigated the available data of the tsunamis in the French West Indies using the historical data and catalogue of the tsunamis in the Lesser Antilles. In total, twenty-four (24) tsunamis were recorded in this area for last 400 years; sixteen (16) events of the seismic origin, five (5) events of volcanic origin and three (3) events of unknown source. Most of the tsunamigenic earthquakes (13) occurred in the Caribbean, and three tsunamis were generated during far away earthquakes (near the coasts of Portugal and Costa Rica). The estimates of tsunami risk are based on a preliminary analysis of the seismicity of the Caribbean area and the historical data of tsunamis. In particular, we investigate the occurrence of historical extreme runup tsunami data on Guadeloupe, and these data are revised after a survey in Guadeloupe.

N. Zahibo; E. N. Pelinovsky

2001-01-01

64

The 30 December 2002 landslide-induced tsunamis in Stromboli: sequence of the events reconstructed from the eyewitness accounts  

Digital Repository Infrastructure Vision for European Research (DRIVER)

On 30 December 2002 the coast of the volcanic island of Stromboli, in the Tyrrhenian sea, Italy, was attacked by two tsunamis generated by landslides that took place on the north-west flank of the volcano. The landslides and the tsunamis represented the most impressive and threatening episodes of a ...

Tinti, S.; Manucci, A.; Pagnoni, G.; Armigliato, A.; Zaniboni, F.

65

THE POTENTIAL OF TSUNAMI GENERATION ALONG THE MAKRAN SUBDUCTION ZONE IN THE NORTHERN ARABIAN SEA. CASE STUDY: THE EARTHQUAKE AND TSUNAMI OF NOVEMBER 28, 1945  

Directory of Open Access Journals (Sweden)

Full Text Available Although large earthquakes along the Makran Subduction Zone are infrequent, the potential for the generation of destructive tsunamis in the Northern Arabian Sea cannot be overlooked. It is quite possible that historical tsunamis in this region have not been properly reported or documented. Such past tsunamis must have affected Southern Pakistan, India, Iran, Oman, the Maldives and other countries bordering the Indian Ocean.The best known of the historical tsunamis in the region is the one generated by the great earthquake of November 28, 1945 off Pakistan's Makran Coast (Balochistan) in the Northern Arabian Sea. The destructive tsunami killed more than 4,000 people in Southern Pakistan but also caused great loss of life and devastation along the coasts of Western India, Iran, Oman and possibly elsewhere.The seismotectonics of the Makran subduction zone, historical earthquakes in the region, the recent earthquake of October 8, 2005 in Northern Pakistan, and the great tsunamigenic earthquakes of December 26, 2004 and March 28, 2005, are indicative of the active tectonic collision process that is taking place along the entire southern and southeastern boundary of the Eurasian plate as it collides with the Indian plate and adjacent microplates. Tectonic stress transference to other, stress loaded tectonic regions could trigger tsunamigenic earthquakes in the Northern Arabian Sea in the future.The northward movement and subduction of the Oman oceanic lithosphere beneath the Iranian micro-plate at a very shallow angle and at the high rate is responsible for active orogenesis and uplift that has created a belt of highly folded and densely faulted coastal mountain ridges along the coastal region of Makran, in both the Balochistan and Sindh provinces. The same tectonic collision process has created offshore thrust faults. As in the past, large destructive tsunamigenic earthquakes can occur along major faults in the east Makran region, near Karachi, as well as along the western end of the subduction zone. In fact, recent seismic activity indicates that a large earthquake is possible in the region west of the 1945 event. Such an earthquake can be expected to generate a destructive tsunami.Additionally, the on-going subduction of the two micro-plates has dragged tertiary marine sediments into an accretionary prism - thus forming the Makran coastal region, Thick sediments, that have accumulated along the deltaic coastlines from the erosion of the Himalayas, particularly along the eastern Sindh region near the Indus River delta, have the potential to fail and cause large underwater tsunamigenic slides. Even smaller magnitude earthquakes could trigger such underwater landslides. Finally, an earthquake similar to that of 1945 in the Makran zone of subduction, has the potential of generating a bookshelf type of failure within the compacted sediments – as that associated with the “silent” and slow 1992 Nicaragua earthquake – thus contributing to a more destructive tsunami. In conclusion, the Makran subduction zone has a relatively high potential for large tsunamigenic earthquakes.

George Pararas-Carayannis

2006-01-01

66

The BABAYAGA event generator  

Energy Technology Data Exchange (ETDEWEB)

The program BABAYAGA is an event generator for QED processes at flavour factories, mainly intended for luminosity measurement of e {sup +} e {sup -} colliders in the center of mass range 1-10 GeV. Recently, the {pi}{sup +}{pi}{sup -} channel has been added as well. The relevant (photonic) radiative corrections are simulated by means of a Parton Shower in QED. The theoretical precision of the approach is estimated and some phenomenological results are discussed.

Carloni Calame, C.M. [Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, Via A. Bassi, 6 - 27100 Pavia (Italy); Dipartimento di Fisica Nucleare e Teorica, Via A. Bassi, 6 - 27100 Pavia (Italy); Montagna, G. [Dipartimento di Fisica Nucleare e Teorica, Via A. Bassi, 6 - 27100 Pavia (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, Via A. Bassi, 6 - 27100 Pavia (Italy); Nicrosini, O. [Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, Via A. Bassi, 6 - 27100 Pavia (Italy); Dipartimento di Fisica Nucleare e Teorica, Via A. Bassi, 6 - 27100 Pavia (Italy); Piccinini, F. [Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, Via A. Bassi, 6 - 27100 Pavia (Italy); Dipartimento di Fisica Nucleare e Teorica, Via A. Bassi, 6 - 27100 Pavia (Italy)

2004-04-15

67

Ionospheric Method of Detecting Tsunami-Generating Earthquakes.  

Science.gov (United States)

Reviews the earthquake phenomenon and its possible relation to ionospheric disturbances. Discusses the basic physical principles involved and the methods upon which instrumentation is being developed for possible use in a tsunami disaster warning system. (GA)

Najita, Kazutoshi; Yuen, Paul C.

1978-01-01

68

TSUNAMI GENERATED BY THE VOLCANO ERUPTION ON JULY 12-13, 2003 AT MONTSERRAT, LESSER ANTILLES  

Directory of Open Access Journals (Sweden)

Full Text Available A major collapse of a lava dome occurred at the Soufrière Hills Volcano (Montserrat, Lesser Antilles), culminating late in the evening (11:35 PM local time) on July 12, 2003 (03:35 GMT on 13 July). This generated a tsunami, which was recorded on Montserrat 2-4 km from the generating area and Guadeloupe, 50 km from Montserrat. Results of field surveys are presented. Tsunami wave height on Montserrat may have been about 4 m according to the location of a strandline of charred trees and other floating objects at Spanish Point on the east coast of the island. The wave height on Guadeloupe according to “direct” witnesses was about 0.5-1 m at Deshaies and near Plage de la Perle. The tsunami at Deshaies caused the scattering of boats as confirmed by fishermen and local authorities. Data from the field survey are in agreement with the predicted tsunami scenario obtained by numerical simulation.

Efim Pelinovsky; Narcisse Zahibo; Peter Dunkley; Marie Edmonds; Richard Herd; Tatiana Talipova; Andrey Kozelkov5; Irina Nikolkina

2004-01-01

69

EVALUATION OF THE THREAT OF MEGA TSUNAMI GENERATION FROM POSTULATED MASSIVE SLOPE FAILURES OF ISLAND STRATOVOLCANOES ON LA PALMA, CANARY ISLANDS, AND ON THE ISLAND OF HAWAII  

Directory of Open Access Journals (Sweden)

Full Text Available Massive flank failures of island stratovolcanoes are extremely rare phenomena and none have occurred within recorded history. Recent numerical modeling studies, forecasting mega tsunami generation from postulated, massive slope failures of Cumbre Vieja in La Palma, Canary Islands, and Kilauea, in Hawaii, have been based on incorrect assumptions of volcanic island slope instability, source dimensions, speed of failure and tsunami coupling mechanisms. Incorrect input parameters and treatment of wave energy propagation and dispersion, have led to overestimates of tsunami far field effects. Inappropriate media attention and publicity to such probabilistic results have created unnecessary anxiety that mega tsunamis may be imminent and may devastate densely populated coastlines at locations distant from the source - in both the Atlantic and Pacific Oceans.The present study examines the assumptions and input parameters used by probabilistic numerical models and evaluates the threat of mega tsunami generation from flank failures of island stratovolcanoes. Based on geologic evidence and historic events, it concludes that massive flank collapses of Cumbre Vieja or Kilauea volcanoes are extremely unlikely to occur in the near geologic future. The flanks of these island stratovolcanoes will continue to slip aseismically, as in the past. Sudden slope failures can be expected to occur along faults paralleling rift zones, but these will occur in phases, over a period of time, and not necessarily as single, sudden, large-scale, massive collapses. Most of the failures will occur in the upper flanks of the volcanoes, above and below sea level, rather than at the basal decollement region on the ocean floor. The sudden flank failures of the volcanoes of Mauna Loa and Kilauea in 1868 and 1975 and the resulting earthquakes generated only destructive local tsunamis with insignificant far field effects. Caldera collapses and large slope failures associated with volcanic explosions of Krakatau in 1883 and of Santorin in 1490 B.C., generated catastrophic local tsunamis, but no waves of significance at distant locations. Mega tsunami generation, even from the larger slope failures of island stratovolcanoes, is extremely unlikely to occur. Greater source dimensions and longer wave periods are required to generate tsunamis that can have significant, far field effects. The threat of mega tsunami generation from massive flank failures of island stratovolcanoes has been greatly overstated.

George Pararas-Carayannis

2002-01-01

70

EXPERIMENTAL MODELING OF TSUNAMI GENERATED BY UNDERWATER LANDSLIDES  

Directory of Open Access Journals (Sweden)

Full Text Available Preliminary results from a set of laboratory experiments aimed at producing a high-quality dataset for modeling underwater landslide-induced tsunami are presented. A unique feature of these experiments is the use of a method to measure water surface profiles continuously in both space and time rather than at discrete points. Water levels are obtained using an optical technique based on laser induced fluorescence, which is shown to be comparable in accuracy and resolution to traditional electrical point wave gauges. The ability to capture the spatial variations of the water surface along with the temporal changes has proven to be a powerful tool with which to study the wave generation process.In the experiments, the landslide density and initial submergence are varied and information of wave heights, lengths, propagation speeds, and shore run-up is measured. The experiments highlight the non- linear interaction between slider kinematics and initial submergence, and the wave field.The ability to resolve water levels spatially and temporally allows wave potential energy time histories to be calculated. Conversion efficiencies range from 1.1%-5.9% for landslide potential energy into wave potential energy. Rates for conversion between landslide kinetic energy and wave potential energy range between 2.8% and 13.8%.The wave trough initially generated above the rear end of the landslide propagates in both upstream and downstream directions. The upstream-travelling trough creates the large initial draw-down at the shore. A wave crest generated by the landslide as it decelerates at the bottom of the slope causes the maximum wave run-up height observed at the shore.

Langford P. Sue; Roger I. Nokes; Roy A. Walters

2006-01-01

71

On the use of finite fault solution for tsunami generation problems  

CERN Document Server

The present study is devoted to the tsunami wave generation problem. The main goal of this work is two-fold. First of all, we propose a simple and computationally inexpensive model for the description of the sea bed displacement during an underwater earthquake, based on the finite fault solution for the slip distribution under some assumptions on the rupturing process dynamics. Once the bottom motion is reconstructed, we study waves induced on the free surface of the ocean. For this purpose we consider three different models approximating the Euler equations of the water wave theory. Namely, we deal with linearized Euler equations (also known as Cauchy-Poisson problem), a Boussinesq system and a weakly nonlinear model. An intercomparison of these approaches is performed. All developments in this study are illustrated on the real world example of the July 17, 2006 Java event.

Dutykh, Denys; Gardeil, Xavier

2010-01-01

72

Constraints on eruption processes and source conditions of explosive caldera-forming events using volcanogenic tsunamis: insights from the Krakatau and Kikai eruptions  

Science.gov (United States)

Caldera-forming eruptions are catastrophic volcanic events that pose one of the great natural hazards on earth. The 1883 eruption of Krakatau in Indonesia (VEI 6) and the 7.3 ka Kikai eruption (VEI 7) of Japan are the representative of young marine caldera-forming eruptions. Although these eruptions must have significantly and devastatingly affected the development of coastal human activities and environments around the volcanoes, they still remain speculative and controversial, particularly with respect to the effects of seawater on eruption processes, dynamics, and evolution of such large-scale marine eruptions. In this presentation impacts of volcanogenic tsunamis during these two caldera-forming eruptions are discussed based on geological evidences and results of numerical studies. Then eruption processes and source conditions are estimated. A key issue is that which tsunami generation mechanism is more plausible for each eruption; caldera collapse, phreatomagmatic explosion, or pyroclastic flow? Tsunamis generated by pyroclastic flows can be evaluated using two types of two-layer shallow water model which can simply describe the effects of interaction between pyroclastic flow and seawater. One of the models is for denser flow than seawater, and another is for lighter one. Tsunamis generated by caldera collapse and phreatomagmatic explosion can be evaluated using simple plunger models. Parameter studies were conducted under the various initial conditions for different tsunami mechanisms and for both eruption. For the Krakatau eruption, computed wave heights of tsunamis are broadly consistent with historical wave data in coastal areas, including a tide gage record at Batavia, when the flow has a volume of 20 km3 and a mass flux of 108 m3/s. The result indicates that a voluminous pyroclastic flow entering sea would be a plausible mechanism. On the other hand, for the Kikai eruption, a caldera collapse is a possible mechanism for a huge tsunami and its timescale can be estimated less than 6 hours by comparing numerical results with limited geological records. It is suggested that volcanogenic tsunamis would give quantitative constraints on eruption processes and source conditions of explosive marine eruptions.

Maeno, F.; Imamura, F.

2010-12-01

73

Numerical simulation of tsunami generation by cold volcanic mass flows at Augustine Volcano, Alaska  

Directory of Open Access Journals (Sweden)

Full Text Available Many of the world's active volcanoes are situated on or near coastlines. During eruptions, diverse geophysical mass flows, including pyroclastic flows, debris avalanches, and lahars, can deliver large volumes of unconsolidated debris to the ocean in a short period of time and thereby generate tsunamis. Deposits of both hot and cold volcanic mass flows produced by eruptions of Aleutian arc volcanoes are exposed at many locations along the coastlines of the Bering Sea, North Pacific Ocean, and Cook Inlet, indicating that the flows entered the sea and in some cases may have initiated tsunamis. We evaluate the process of tsunami generation by cold granular subaerial volcanic mass flows using examples from Augustine Volcano in southern Cook Inlet. Augustine Volcano is the most historically active volcano in the Cook Inlet region, and future eruptions, should they lead to debris-avalanche formation and tsunami generation, could be hazardous to some coastal areas. Geological investigations at Augustine Volcano suggest that as many as 12–14 debris avalanches have reached the sea in the last 2000 years, and a debris avalanche emplaced during an A.D. 1883 eruption may have initiated a tsunami that was observed about 80 km east of the volcano at the village of English Bay (Nanwalek) on the coast of the southern Kenai Peninsula. Numerical simulation of mass-flow motion, tsunami generation, propagation, and inundation for Augustine Volcano indicate only modest wave generation by volcanic mass flows and localized wave effects. However, for east-directed mass flows entering Cook Inlet, tsunamis are capable of reaching the more populated coastlines of the southwestern Kenai Peninsula, where maximum water amplitudes of several meters are possible.

C. F. Waythomas; P. Watts; J. S. Walder

2006-01-01

74

Numerical simulation of tsunami generation by cold volcanic mass flows at Augustine Volcano, Alaska  

Science.gov (United States)

Many of the world's active volcanoes are situated on or near coastlines. During eruptions, diverse geophysical mass flows, including pyroclastic flows, debris avalanches, and lahars, can deliver large volumes of unconsolidated debris to the ocean in a short period of time and thereby generate tsunamis. Deposits of both hot and cold volcanic mass flows produced by eruptions of Aleutian arc volcanoes are exposed at many locations along the coastlines of the Bering Sea, North Pacific Ocean, and Cook Inlet, indicating that the flows entered the sea and in some cases may have initiated tsunamis. We evaluate the process of tsunami generation by cold granular subaerial volcanic mass flows using examples from Augustine Volcano in southern Cook Inlet. Augustine Volcano is the most historically active volcano in the Cook Inlet region, and future eruptions, should they lead to debris-avalanche formation and tsunami generation, could be hazardous to some coastal areas. Geological investigations at Augustine Volcano suggest that as many as 12-14 debris avalanches have reached the sea in the last 2000 years, and a debris avalanche emplaced during an A.D. 1883 eruption may have initiated a tsunami that was observed about 80 km east of the volcano at the village of English Bay (Nanwalek) on the coast of the southern Kenai Peninsula. Numerical simulation of mass-flow motion, tsunami generation, propagation, and inundation for Augustine Volcano indicate only modest wave generation by volcanic mass flows and localized wave effects. However, for east-directed mass flows entering Cook Inlet, tsunamis are capable of reaching the more populated coastlines of the southwestern Kenai Peninsula, where maximum water amplitudes of several meters are possible.

Waythomas, C. F.; Watts, P.; Walder, J. S.

2006-01-01

75

Tsunami generation from the Santa Catalina Island restraining bend offshore of Los Angeles, California  

Science.gov (United States)

We model the Santa Catalina Island platform as a pop up structure in a major restraining bend along a right-slip fault zone. We are assuming that the shape of the sea floor uplift replicates the finite deformation associated with combined right slip and reverse faulting during major earthquakes on the Catalina fault. We successfully model the seafloor and island uplift with two major fault sections comprised of seven individual segments. As observed in several other restraining bends, offshore southern California, the two major fault sections are arranged in a right stepping en echelon pattern. These two major fault sections are evident in bathymetry and topography as sea floor scarps and deflected drainages on the island. The best fit to the existing bathymetry and topography is achieved with a total fault length of 150 km with segments dipping from 60 to 90 degrees to the northeast. A fault width of 14 km extending from a depth of 0.5 to 1.5 km is used. Fault slips vary from 3.5 to 6.5 m and results in surface uplifts of up to 2.2 m centered on the island near Mt. Orizaba. The simulated earthquake has an approximate moment magnitude of 7.6, and the predicted surface displacements are comparable to surface faulting measured in recent magnitude 7 to 7.6 earthquakes worldwide. Tsunami generation as a result of this event generates effectively two wave fronts from the opposite submerged ends of the island platform with initial wave heights of up to 1.5 m. It is important to note that the maximum uplift in this scenario occurs on land and does not directly contribute to tsunami generation. Resulting wave interference patterns create zones of elevated runup along the coast. With this initial fault model we will proceed to consider other faulting scenarios comprised of different segment combinations, slip distributions and earthquake magnitudes.

Legg, M. R.; Borrero, J. C.; Synolakis, C. E.

2003-04-01

76

W Phase Inversion and Tsunami Inundation Modeling for Tsunami Early Warning: Case Study for the 2011 Tohoku Event  

Science.gov (United States)

Centroid moment tensor solutions for the 2011 Tohoku earthquake are determined by W phase inversions using 5 and 10 min data recorded by the Full Range Seismograph Network of Japan (F-net). By a scaling relation of moment magnitude to rupture area and an assumption of rigidity of 4 × 1010 N m-2, simple rectangular earthquake fault models are estimated from the solutions. Tsunami inundations in the Sendai Plain, Minamisanriku, Rikuzentakata, and Taro are simulated using the estimated fault models. Then the simulated tsunami inundation area and heights are compared with the observations. Even the simulated tsunami heights and inundations from the W phase solution that used only 5 min data are considerably similar to the observations. The results are improved when using 10 min of W phase data. These show that the W phase solutions are reliable to be used for tsunami inundation modeling. Furthermore, the technique that combines W phase inversion and tsunami inundation modeling can produce results that have sufficient accuracy for tsunami early warning purposes.

Gusman, Aditya Riadi; Tanioka, Yuichiro

2013-05-01

77

Tsunami Attack!  

Science.gov (United States)

Students learn about tsunamis, discovering what causes them and what makes them so dangerous. They learn that engineers design detection and warning equipment, as well as structures that that can survive the strong wave forces. In a hands-on activity, students use a table-top-sized tsunami generator to observe the formation and devastation of a tsunami. They see how a tsunami moves across the ocean and what happens when it reaches a coastline. They make villages of model houses to test how different material types are impacted by the huge waves.

Integrated Teaching And Learning Program

78

Recent Tsunami Highlights Need for Awareness of Tsunami Duration  

Science.gov (United States)

On Wednesday, 15 November 2006, Crescent City Harbor, in Del Norte County, Calif., was hit by surges resulting from the tsunami generated by the Mw=8.3 Kuril Islands earthquake. The strong currents caused an estimated US $700,000 to $1 million in losses to the small boat basin at Citizen's Dock, destroying or damaging three floating docks and causing minor damage to several boats (Figure 1). The event highlighted a persistent problem for tsunami hazard mitigation: Most people are still unaware that the first tsunami waves rarely are the largest and that the potential for damaging waves may last for many hours.

Kelly, Annabel; Dengler, Lori A.; Uslu, Burak; Barberopoulou, Aggeliki; Yim, Solomon C.; Bergen, Kristian J.

2006-12-01

79

Evidence of tsunami events in the Paleolimnological record of Lake Pátzcuaro, Michoacán, Mexico  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish El actual lago de Pátzcuaro tiene una elevación de 2035 m sobre el nivel del mar. Históricamente, ha alcanzado una elevación de 2041 m, lo cual aislaba una porción de la isla cerca de la población de Jarácuaro en la parte sureste del lago. Dos trincheras realizadas en la antigua isla revelan secuencias estratigráficas tripartitas similares. En una trinchera de 3.1 m de profundidad, la secuencia de la base a la cima está formada por la Unidad A que comprende arcil (more) las y limos ricos en diatomeas plegados y fallados con capas de arena volcánica. Estos depósitos están fechados entre 24 y 10 mil años BP. Unidad B que comprende una mezcla caótica de arenas volcánicas y lapilli, con abundantes restos de peces, bivalvos, gasterópodos y ostrácodos, de 10 cm de espesor con un contacto erosivo sobre la Unidad A. Los ostrácodos incluyen valvas articuladas con una mezcla de especies pelágicas de agua profunda y especies litorales. Los fragmentos de artefactos cerámicos pertenecientes al Período Post-Clásico (900 a 1520 AD) son abundantes. La Unidad C comprende una unidad de 20 cm de espesor de limo arcilloso rico en materia orgánica con restos de gasterópodos, semillas, líticos angulares y fragmentos de piezas cerámicas del Post-Clásico. La Unidad B sugiere una resedimentación catastrófica de los depósitos del piso del lago atribuidos a un tsunami. La Unidad C es consistente con condiciones sublacustres que están históricamente documentadas de 1858 a 1947. Un tsunami en el Lago de Pátzcuaro en 1858 ha sido registrado históricamente. El tsunami pudo haber sido creado por movimientos de falla o colapso del flanco suroeste de la isla de Janitzio. La ola del tsunami pudo haber contribuido al rápido aumento del lago de Pátzcuaro después del evento sísmico de 1858. Abstract in english Modern Lake Pátzcuaro has a surface elevation of 2035 m a.s.l. Historically, it reached an elevation of 2041 m a.s.l., which isolated a portion of the island near the town of Jarácuaro in the southeastern part of the lake. Two trenches in the former island reveal similar tripartite stratigraphic sequences. In a 3.1 m deep trench, the sequence from bottom to top comprises Unit A constituted by folded and faulted diatom-rich clay and silt with beds of volcanic sand. These (more) deposits are dated between 24 and 10 ky BP; Unit B constituted by a 10 of cm chaotic mixture of volcanic sand and lapilli with abundant remains of fish, bivalves, gastropods and ostracodes that is rests on above an erosional unconformity. The ostracodes include articulated valves with a mixture of deep-water pelagic species and attached littoral species. Highly fractured diatom shows a mixture of planktonic and benthic habitats. Fragments of ceramic artifacts dated to the Post-Classic Period (900 to 1520 AD) are abundant; Unit Cconstituted by a 20 cm thick unit of organic-rich argillaceous silt with remains of gastropods, seeds, angular lithoclasts and fragments of Post-Classic ceramic artifacts. Unit B suggests a catastrophic resedi mentation of lake floor deposits attributed to a tsunami. Unit C is consistent with sublacustrine conditions that are historically documented from 1858 to 1947. A tsunami in Lake Pátzcuaro in 1858 has been historically recorded. The tsunami was created either by fault movement or collapse of the SW flank of the island of Janitzio. The tsunami wave may have contributed to the rapid rise of Lake Pátzcuaro following the 1858 seismic event.

Garduño-Monroy, Victor Hugo; Soria-Caballero, Diana Cinthia; Israde-Alcántara, Isabel; Hernández Madrigal, Víctor Manuel; Rodríguez-Ramírez, Alejandro; Ostroumov, Mikhail; Rodríguez-Pascua, Miguel Ángel; Chacon-Torres, Arturo; Mora-Chaparro, Juan Carlos

2011-06-01

80

The El Asnam 1980 October 10 inland earthquake: a new hypothesis of tsunami generation  

Science.gov (United States)

The Western Mediterranean Sea is not considered as a high seismic region. Only several earthquakes with magnitude above five occur each year and only a handful have consequences on human beings and infrastructure. The El Asnam (Algeria) earthquake of 1980 October 10 with an estimated magnitude Ms= 7.3 is one of the most destructive earthquakes recorded in northern Africa and more largely in the Western Mediterranean Basin. Although it is located inland, it is known to have been followed by a small tsunami recorded on several tide gauges along the southeastern Spanish Coast. In 1954, a similar earthquake having occurred at the same location induced a turbidity current associated to a submarine landslide, which is widely known to have cut submarine phone cables far from the coast. This event was followed by a small tsunami attributed to the landslide. Thus the origin of the tsunami of 1980 was promptly attributed to the same kind of submarine slide. As no evidence of such mass movement was highlighted, and because the tsunami wave periods does not match with a landslide origin in both cases (1954 and 1980), this study considers two rupture scenarios, that the coseismic deformation itself (of about 10 cm off the Algerian coast near Ténès) is sufficient to produce a low amplitude (several centimetres) tsunami able to reach the Spanish southeastern coast from Alicante to Algeciras (Gibraltar strait to the west). After a discussion concerning the proposed rupture scenarios and their respective parameters, numerical tsunami modelling is performed on a set of bathymetric grids. Then the results of wave propagation and amplification (maximum wave height maps) are discussed, with a special attention to Alicante (Spain) Harbour where the location of two historical tide gauges allows the comparison between synthetic mareograms and historical records showing sufficient signal amplitude. This study is part of the active tsunami hazard assessment in Mediterranean Sea especially concerning its occidental part, that is, the Algerian, Spanish and French coasts.

Roger, J.; Hébert, H.; Ruegg, J.-C.; Briole, P.

2011-06-01

 
 
 
 
81

The Tsunami Geology of the Bay of Bengal Shores and the Predecessors of the 2004 Indian Ocean Event  

Science.gov (United States)

The 2004 Aceh-Andaman earthquake exceeded the known Indian Ocean precedents by its 1,300-km long fault rupture and the height and reach of its tsunami. Literature of the ancient Chola dynasty (AD 9-11 centuries) of south India and the archeological excavations allude to a sea flood that crippled the historic port at Kaveripattinam, a trading hub for Southeast Asia. Here, we combine a variety of data from the rupture zone as well as the distant shores to build a tsunami history of the Bay of Bengal. A compelling set of geological proxies of possible tsunami inundation include boulder beds of Car Nicobar Island in the south and the East Island in the northernmost Andaman, a subsided fossil mangrove forest near Port Blair and a washover sedimentation identified in the Kaveripattinam coast of Tamil Nadu, south India. We have developed an extensive chronology for these geological proxies, and we analyze them in conjunction with the historical information culled from different sources for major sea surges along the Bay of Bengal shores. The age data and the depositional characteristics of these geological proxies suggest four major tsunamis in the last 2000 years in the Bay of Bengal, including the 1881 Car Nicobar tsunami. Among these, the evidence for the event of 800-1200 cal yr BP is fairly well represented on both sides of the Bay of Bengal shores. Thus, we surmise that the 800-1000-year old tsunami mimics the transoceanic reach of the 2004 Indian Ocean and the age constraints also agree with the sea surge during the Chola period. We also obtained clues for a possible medieval tsunami from the islands occurred probably a few hundred years after the Chola tsunami, but its size cannot constrained, nor its source. The convergence of ages and the multiplicity of sites would suggest at least one full size predecessor of the 2004 event 1000-800 years ago.

Rajendran, C.; Rajendran, K.; Seshachalam, S.; Andrade, V.

2010-12-01

82

Waves of Destruction: Tsunamis  

Science.gov (United States)

Web companion to an episode of the PBS/WNET television series "Savage Earth" devoted to tsunamis. The homepage article provides a brief overview of the mechanism that creates tsunamis, the enormous energy they release, and the role of plate tectonics in earthquake and tsunami generation. Sidebar pages discuss tsunami monitoring and advance warning, and geologic investigations that reveal evidence of destructive tsunamis in the past. There is also an animation that shows how an earthquake at a subduction zone can cause the sea floor to snap upward abruptly, displacing water and generating a tsunami, and a video interview with a survivor of the 1946 tsunami that struck the Hawaiian Islands.

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Tsunami generation by dynamic displacement of sea bed due to dip-slip faulting  

CERN Multimedia

In classical tsunami-generation techniques, one neglects the dynamic sea bed displacement resulting from fracturing of a seismic fault. The present study takes into account these dynamic effects. Earth's crust is assumed to be a Kelvin-Voigt material. The seismic source is assumed to be a dislocation in a viscoelastic medium. The fluid motion is described by the classical nonlinear shallow water equations (NSWE) with time-dependent bathymetry. The viscoelastodynamic equations are solved by a finite-element method and the NSWE by a finite-volume scheme. A comparison between static and dynamic tsunami-generation approaches is performed. The results of the numerical computations show differences between the two approaches and the dynamic effects could explain the complicated shapes of tsunami wave trains.

Dutykh, Denys

2007-01-01

84

TSUNAMI INFORMATION SOURCES - PART 4  

Directory of Open Access Journals (Sweden)

Full Text Available I have expanded substantially my list of information sources on: tsunami generation (sources, impulsive mechanisms), propagation, effects of nearshore bathymetry, and wave run-up on shore - including physical (hydraulic) modeling and numerical modeling. This expanded list includes the subjects of field investigations of tsunamis soon after an event; damage effects in harbors on boats, ships, and facilities; tsunami wave-induced forces; damage by tsunami waves to structures on shore; scour/erosion; hazard mitigation; land use planning; zoning; siting, design, construction and maintenance of structures and infrastructure; public awareness and education; distant and local sources; tsunami warning and evacuation programs; tsunami probability and risk criteria. A few references are on "sedimentary signatures" useful in the study of historic and prehistoric tsunamis (paleo-tsunamis). In addition to references specifically on tsunamis, there are references on long water wave and solitary wave theory; wave refraction, diffraction, and reflection; shelf and basin free and forced oscillations (bay and harbor response; seiches); edge waves; Mach- reflection of long water waves ("stem waves"); wave run-up on shore; energy dissipation. All are important in understanding tsunamis, and in hazard mitigation. References are given on subaerial and submarine landslide (and rockfall) generated waves in reservoirs, fjords, bays, and ocean; volcano explosive eruptions/collapse; underwater and surface explosions; asteroid impact. This report is in two parts: 1) Bibliographies, books and pamphlets, catalogs, collections, journals and newsletters, maps, organizations, proceedings, videos and photos; 2) Articles, papers, reports listed alphabetically by author.Many papers on the Indian Ocean (Sumatra) tsunami of 26 December 2004, were given at the 22nd IUGG International Tsunami Symposium, Chania, Crete, 27-29 June 2005, but had not been published at the date of this report. For the program, see http://www.gein.noa.gr/English/tsunamis.htmThis list of tsunami information sources (115 pp, about 3,300 entries) is also available on a diskette, at the Water Resources Center Archives, 410 O'Brien Hall, University of California, Berkeley, CA, 94720-1718. Most of the publications are available in the Water Resources Center Archives or the Earth Sciences Library, University of California, Berkeley, CA.I wish to acknowledge my appreciation of the great help of the staff of the Water Resources Center Archives in finding some difficult to obtain publications; in particular Paul S. Atwood for his help for those on websites and other computer sources. I want to thank John M. Wiegel for his continuous help in searching for sources on websites via computer search-engines.

Robert L. Wiegel

2006-01-01

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Modeling of Tsunami Generation and Propagation by a Spreading Curvilinear Seismic Faulting in Linearized Shallow-Water Wave Theory  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The processes of tsunami evolution during its generation in search for possible amplification mechanisms resulting from unilateral spreading of the sea floor uplift is investigated. We study the nature of the tsunami build up and propagation during and after realistic curvilinear source models repre...

Hossam S. Hassan; Khaled T. Ramadan; Sarwat N. Hanna

86

SATELLITE TRANSMITTED FLOOD ALERTS TO REDUCE FATALITIES AND INJURIES ON THE ISLAND OF HAWAII ASSOCIATED WITH LOCALLY GENERATED TSUNAMIS  

Directory of Open Access Journals (Sweden)

Full Text Available Tsunami detection instruments were installed along remote shoreline campgrounds of Hawaii Volcanoes National Park in August of 2009. Components include water sensing devices at elevations of about 10 feet above sea level located at distances of about 200 feet from the shoreline and satellite communicators located further inland at higher elevations that will send daily status reports and flood alerts from the water sensors as they occur to the Pacific Tsunami Warning Center in Honolulu. Such instruments will provide for earlier warnings of significant locally generated tsunamis than previously possible. These instruments will also provide a basis for early warnings of locally generated tsunamis to those campgrounds using siren systems to be designed specifically for those remote environments. Suggestions of additional actions that could also reduce future fatalities and injuries at those campgrounds as a result of locally generated tsunamis are also provided in this report.

Daniel A. Walker

2010-01-01

87

NOAA/West coast and Alaska Tsunami warning center Atlantic Ocean response criteria  

Science.gov (United States)

West Coast/Alaska Tsunami Warning Center (WCATWC) response criteria for earthquakesoccurring in the Atlantic and Caribbean basins are presented. Initial warning center decisions are based on an earthquake's location, magnitude, depth, distance from coastal locations, and precomputed threat estimates based on tsunami models computed from similar events. The new criteria will help limit the geographical extent of warnings and advisories to threatened regions, and complement the new operational tsunami product suite. Criteria are set for tsunamis generated by earthquakes, which are by far the main cause of tsunami generation (either directly through sea floor displacement or indirectly by triggering of sub-sea landslides).The new criteria require development of a threat data base which sets warning or advisory zones based on location, magnitude, and pre-computed tsunami models. The models determine coastal tsunami amplitudes based on likely tsunami source parameters for a given event. Based on the computed amplitude, warning and advisory zones are pre-set.

Whitmore, P.; Refidaff, C.; Caropolo, M.; Huerfano-Moreno, V.; Knight, W.; Sammler, W.; Sandrik, A.

2009-01-01

88

Assessment of the safety of Ulchin nuclear power plant in the event of tsunami using parametric study  

International Nuclear Information System (INIS)

Previous evaluations of the safety of the Ulchin Nuclear Power Plant in the event of a tsunami have the shortcoming of uncertainty of the tsunami sources. To address this uncertainty, maximum and minimum wave heights at the intake of Ulchin NPP have been estimated through a parametric study, and then assessment of the safety margin for the intake has been carried out. From the simulation results for the Ulchin NPP site, it can be seen that the coefficient of eddy viscosity considerably affects wave height at the inside of the breakwater. In addition, assessment of the safety margin shows that almost all of the intake water pumps have a safety margin over 2 m, and Ulchin NPP site seems to be safe in the event of a tsunami according to this parametric study, although parts of the CWPs rarely have a margin for the minimum wave height

2011-01-01

89

Potential predecessors of the 2004 Indian Ocean Tsunami — Sedimentary evidence of extreme wave events at Ban Bang Sak, SW Thailand  

Science.gov (United States)

Where historical records are short and/or fragmentary, geological evidence is an important tool to reconstruct the recurrence rate of extreme wave events (tsunamis and/or storms). This is particularly true for those coastal zones around the Indian Ocean, where predecessors of similar magnitude as the 2004 Indian Ocean Tsunami (IOT) have not been reported by written sources. In this context, the sedimentary record of the Holocene coastal plain of Ban Bang Sak (Phang-nga province, Thailand) provides evidence of multiple prehistoric coastal flooding events in the form of allochthonous sand beds, which were radiocarbon dated to 700-500, 1350-1180, and younger than 2000 cal BP. The layers were assigned to high-energy events of marine origin, which could be either tsunamis or tropical storms, by means of granulometry, geochemistry, vertical structure, and macrofossil content. Although no landfall of a strong storm has occurred in the last 150 years of meteorological data recording, cyclones cannot be ruled out for the last centuries and millennia. However, discrimination between tsunami and storm origin was mainly based on the comparison of the palaeoevent beds with the local deposit of the IOT, which revealed similar characteristics in regard to spatial extend and sediment properties. Furthermore, the youngest palaeoevent correlates with contemporaneous deposits from Thailand and more distant coasts. Hence, we relate it to a basin wide tsunami which took place 700-500 years ago. For the sediments of older extreme events, deposited between 2000 and 1180 cal BP, we found no unambiguous counterparts at other sites; nevertheless, at least for now, they are treated as tsunami candidates.

Brill, D.; Brückner, H.; Jankaew, K.; Kelletat, D.; Scheffers, A.; Scheffers, S.

2011-08-01

90

Modeling for the SAFRR Tsunami Scenario-generation, propagation, inundation, and currents in ports and harbors: Chapter D in The SAFRR (Science Application for Risk Reduction) Tsunami Scenario  

Science.gov (United States)

This U.S. Geological Survey (USGS) Open-File report presents a compilation of tsunami modeling studies for the Science Application for Risk Reduction (SAFRR) tsunami scenario. These modeling studies are based on an earthquake source specified by the SAFRR tsunami source working group (Kirby and others, 2013). The modeling studies in this report are organized into three groups. The first group relates to tsunami generation. The effects that source discretization and horizontal displacement have on tsunami initial conditions are examined in section 1 (Whitmore and others). In section 2 (Ryan and others), dynamic earthquake rupture models are explored in modeling tsunami generation. These models calculate slip distribution and vertical displacement of the seafloor as a result of realistic fault friction, physical properties of rocks surrounding the fault, and dynamic stresses resolved on the fault. The second group of papers relates to tsunami propagation and inundation modeling. Section 3 (Thio) presents a modeling study for the entire California coast that includes runup and inundation modeling where there is significant exposure and estimates of maximum velocity and momentum flux at the shoreline. In section 4 (Borrero and others), modeling of tsunami propagation and high-resolution inundation of critical locations in southern California is performed using the National Oceanic and Atmospheric Administration’s (NOAA) Method of Splitting Tsunami (MOST) model and NOAA’s Community Model Interface for Tsunamis (ComMIT) modeling tool. Adjustments to the inundation line owing to fine-scale structures such as levees are described in section 5 (Wilson). The third group of papers relates to modeling of hydrodynamics in ports and harbors. Section 6 (Nicolsky and Suleimani) presents results of the model used at the Alaska Earthquake Information Center for the Ports of Los Angeles and Long Beach, as well as synthetic time series of the modeled tsunami for other selected locales in southern California. Importantly, section 6 provides a comparison of the effect of including horizontal displacements at the source described in section 1 and differences in bottom friction on wave heights and inundation in the Ports of Los Angeles and Long Beach. Modeling described in section 7 (Lynett and Son) uses a higher order physical model to determine variations of currents during the tsunami and complex flow structures such as jets and eddies. Section 7 also uses sediment transport models to estimate scour and deposition of sediment in ports and harbors—a significant effect that was observed in southern California following the 2011 Tohoku tsunami. Together, all of the sections in this report form the basis for damage, impact, and emergency preparedness aspects of the SAFRR tsunami scenario. Three sections of this report independently calculate wave height and inundation results using the source specified by Kirby and others (2013). Refer to figure 29 in section 3, figure 52 in section 4, and figure 62 in section 6. All of these results are relative to a mean high water (MHW) vertical datum. Slight differences in the results are observed in East Basin of the Port of Los Angeles, Alamitos Bay, and the Seal Beach National Wildlife Refuge. However, given that these three modeling efforts involved different implementations of the source, different numerical wave propagation and runup models, and slight differences in the digital elevation models (DEMs), the similarity among the results is remarkable.

SAFRR Tsunami Modeling Working Group

2013-01-01

91

Inclusion of landslide tsunamis generation into a depth integrated wave model  

Directory of Open Access Journals (Sweden)

Full Text Available A numerical model based on the mild slope equation, suitable to reproduce the propagation of small amplitude tsunamis in the far field, is extended to reproduce the generation and the propagation of waves generated by landslides. The wave generation is modeled through a forcing term included in the field equation, which reproduces the effects of the movement of a submerged landslide on the fluid. The measurements of three dimensional laboratory experiments, which simulate tsunamis generated by landslide sliding along the flank of a conical island, are compared with the theoretical calculation results. The present approach is also compared with the similar method of Tinti et al. (2006) used for the generation of these waves in depth integrated model, and the different behavior when using frequency-dispersive and non-dispersive equations is highlighted.

C. Cecioni; G. Bellotti

2010-01-01

92

Tsunami risk assessment in the Marquesas Islands (French Polynesia) through numerical modeling of generic far-field events  

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Full Text Available Earthquakes occurring at the Pacific Rim can trigger tsunamis that propagate across the ocean and can produce significant damages far away from the source. In French Polynesia, the Marquesas Islands are the most exposed to the far-field tsunami hazards, since they are not protected by any outer coral reef and since submarine slopes are less steep than in other islands. Between 1994 and 1996, four tsunamis have reached the bays of the archipelago, among them, the tsunami initiated by the Chilean Mw 8.1 earthquake, produced up to 3 m high waves in Tahauku Bay. Numerical modeling of these recent events has already allowed us to validate our method of resolution of hydrodynamics laws through a finite-difference scheme that simulates the propagation of the tsunamis across the ocean and computes the inundation heights (run-up) in remote bays. We present in this paper the simulations carried out to study potentially threatening areas located at the Pacific Rim, on the seismogenic Aleutian and Tonga subduction zones. We use a constant seismic moment source (that of the Mw 8.1 Chile 1995 earthquake, M0 = 1.2 1021 N.m) located at several potential epicenters, with the fault strike adapted from the regional seismotectonics pattern. Our results show that the sources chosen in the Aleutian trench do not produce large inundations in the Marquesas bays, except for the easternmost source (longitude 194° E). Sources located in the Tonga trench do not produce high amplifications either, except for the northernmost one (latitude 16° S). We also discuss the behaviour of the tsunami waves within the archipelago, and evidence contrasting responses depending on the arrival azimuths. These results show that, for a given initial seismic energy, the tsunami amplification in remote bays is highly dependent on the source location and fault strike.

H. Hébert; F. Schindelé; P. Heinrich

2001-01-01

93

A Tsunami Fragility Assessment for Nuclear Power Plants in Korea  

International Nuclear Information System (INIS)

Although Tsunami events were defined as an external event in 'PRA Procedure Guide (NUREG/CR- 2300)'after 1982, a Tsunami event was not considered in a design and construction of NPP before the Sumatra earthquake in 2004. But the Madras Atomic Power Station, a commercial nuclear power plant owned and operated by the Nuclear Power Corporation of India Limited (NPCIL), and located near Chennai, India, was affected by the tsunami generated by the 2004 Sumatra earthquake (USNRC 2008). The condenser cooling pumps of Unit 2 of the installation were affected due to flooding of the pump house and subsequent submergence of the seawater pumps by tsunami waves. The turbine was tripped and the reactor shut down. The unit was brought to a cold-shutdown state, and the shutdown-cooling systems were reported as operating safely. After this event, Tsunami hazards were considered as one of the major natural disasters which can affect the safety of Nuclear Power Plants. The IAEA performed an Extrabudgetary project for Tsunami Hazard Assessment and finally an International Seismic Safety Center (ISSC) established in IAEA for protection from natural disasters like earthquake, tsunami etc. For this reason, a tsunami hazard assessment method determined in this study. At first, a procedure for tsunami hazard assessment method was established, and second target equipment and structures for investigation of Tsunami Hazard assessment were selected. Finally, a sample fragility calculation was performed for one of equipment in Nuclear Power Plant

2009-01-01

94

GEOMORPHIC EVIDENCE AND RELATIVE AND ABSOLUTE DATING RESULTS FOR TSUNAMI EVENTS ON CYPRUS  

Directory of Open Access Journals (Sweden)

Full Text Available For the Mediterranean area, almost 100 tsunamis were recorded in historical sources from Antiquity till present. Recordings often describe the consequences for human lives and buildings in coastal areas. However, little evidence for the geomorphic effects of tsunamis has been collected in thisregion. Tsunami run-up may destroy soil and vegetation. Tsunamis may further move extremely large volumes of coarse clastic material including individual boulders weighing more than 20 t. Trottoirs, supra- littoral cliffs, and tafoni may also be destroyed. Deepwater foraminifers deposited on land also provide evidence for Tsunami action. Recently extensively dispersed tsunami deposits were observed in southwestern and southeastern Cyprus. Field collected evidence proves tsunami action for over 60 km of coastline and about 100 - 150 m inland. Coastal areas up to 15 m asl, sometimes up to a maximum height of 30 - 50 m asl, have been influenced by tsunami action on Cyprus Island. This paper describes these deposits, their morphologic characteristics, and possibilities of relative and absolute dating.Cues for relative age determination are provided by soil and vegetation, tafoning, karstification on displaced boulders, and by post-tsunami cliff and beach rock development. Field evidence suggests that tsunamis occurred during the last few centuries. This time estimate was also supported by the absolute 14C dating of vermetids and calcareous algae crusts on displaced boulders, and by the dating of relocated wood and charcoal. Overall, strong tsunami action can be assumed for the time between 1530 and 1821 AD.

Franziska Whelan; Dieter Kelletat

2002-01-01

95

Numerical modelling of potential submarine landslides and generated tsunami in Sumatra  

Science.gov (United States)

Recent studies suggests that tsunami risk along the SW coast of Sumatra could be due to co-seismic slip along a backthrust at the NE Margin of the Mentawai Island and associated landslides (Singh et al., 2010). Using a combination of high-resolution seismic reflection and bathymetry data, they observed deposits of large submarine landslides at the NE margin of Mentawai Island and suggest that the high wave that occurred in 1797 might have been enhanced by landslides, producing a large localised tsunami. Until now most of the work devoted to tsunami hazard assessment in the area of Sumatra Island focussed on megaearthquakes earthquakes generated tsunamis. Therefore, estimating the run up heights due to submarine landslides is essential for risk mitigation along the SW coast of Sumatra. A series of numerical scenarios are performed here to simulate potential submarine landslides and generated tsunamis in the area of Sumatra Island. The height and velocity of the water wave and the impact zones are calculated using a new numerical model solving the depth-averaged shallow water equations with high order finite volume methods. This model corresponds to the 2D extension of the model developed by Fernández-Nieto et al., 2008. The fluidized mass is modeled using a generalization of the Savage-Hutter model [Savage and Hutter, 1989] by including the role of buoyancy and fluid into the thin-layer equations with a Coulomb-type friction law. Our model takes into account the coupling between the fluid and the landslides and incorporates the rigorous description of topography effects that play a key role in the dynamics of landslides. We study the magnitude of variation of the wave expected depending on the location and volume released. These results shows that landslide generated tsunamis have to be taken into account for risk assessment in the area of Sumatra Island. E.D. Fernández-Nieto, F. Bouchut, D. Bresch, M.J. Castro, A. Mangeney, 2008. A new Savage-Hutter type model for submarine avalanches and generated tsunami, J. Comput. Physics 7720-7754, 227. S.B. Savage, K. Hutter. The dynamics of avalanches of granular materials frominitiation to run-out. Acta Mech. 86, 201-223 (1989) Singh, Satish C., Nugroho D. Hananto, Ajay P. S. Chauhan, H. Permana, Marine Denolle, Andri Hendriyana, Danny Natawidjaja, 2010. Evidence of active backthrusting at the NE Margin of Mentawai Islands, SW Sumatra, Geophys. J. Int., 180(2), 703-714, February 2010

Fernandez-Nieto, E.; Mangeney, A.; Singh, S. C.; Chauhan, A.; Bouchut, F.; Castro Díaz, M.

2010-12-01

96

Detection of very long period seismic signals and acoustic gravity waves generated by large tsunamis Application to tsunami warning Detektion von durch Tsunami erzeugten langperiodischen seismischen Signalen und akustischen Gravitationswellen Anwendung für die Tsunami-Warnung  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Tsunamis sind Naturereignisse, die zu den verheerendsten weltweiten Katastrophen gehören, obwohl sie relativ selten auftreten. Da Tsunamis in letzter Zeit zahlreiche Opfer und schwere Zerstörungen in grossen Küstenregionen verursacht haben, sind sie Ziel intensivierter Forschungen geworden. Die Grun...

Raveloson, Andriamiranto

97

The event generator SIMON  

International Nuclear Information System (INIS)

The utilization and development of SIMON generator work was conducted at LPC.This generator was conceived for simple and versatile simulations of different processes occurring in the nuclear collisions at Fermi Energies. At present it is utilized in a large number of French foreign laboratories. Particularly, certain analyses of INDRA data have been done by use of this generator: estimation of collective energy in the Xe + Sn and Gd + U central collisions; shape and space-time correlation analysis in fragment-fragment and particle-fragment output of the same system; calorimetric study of the Xe + Sn and Ar + Ni system; study of the vaporization for the Ar + Ni system. Recently a number of items were improved or modified, among which: the initial configuration was allowed to be non-spherical what permits the analysis of the semi-central collisions; a so-called pre-fragmentation emission may be included to estimate different time constants implied in the fragmentation process

1997-01-01

98

Building Damage and Business Continuity Management in the Event of Natural Hazards: Case Study of the 2004 Tsunami in Sri Lanka  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Sumatra Earthquake and Indian Ocean Tsunami event on the 26 December 2004 has provided a unique and valuable opportunity to evaluate the performance of various structures, facilities and lifeline systems during the tsunami wave attacks. There are especially meaningful observations concerning the...

Chandana Dinesh Parape; Chinthaka Premachandra; Masayuki Tamura; Abdul Bari; Ranjith Disanayake; Duminda Welikanna

99

2004 Tsunami survey in Comoros and Tanzania with inferences on tsunami risk in the Western Indian Ocean during future mega-thrust events  

Science.gov (United States)

We present a total of 59 new data points of run-up of the 2004 Sumatra tsunami in the Comoros and Tanzania, surveyed in 2006-2008 by International Tsunami Survey Teams. Run-up at the Northeastern tip of Grande Comore (6.8 m) is comparable to Socotra (6.1 m), and surpassed only in the Western Indian Ocean by the catastrophic values in Somalia (run-up 9 m; inundation 700 m). Run-up in Mayotte, and to a lesser extent Zanzibar, show considerable variations (from 1 to 5 m), attributed to the influence of the local structure of the reef surrounding these islands. By contrast, the unreefed islands of Anjouan and Moheli, and the mainland coast of Tanzania around Dar-es-Salaam, feature more consistent values in the 2 to 3 m range. The death toll in Tanzania is revised to at least 20. We then use the MOST code to simulate the propagation on the high seas of both the 2004 tsunami, and of potential future tsunamis under scenarios of mega earthquakes rupturing in the South Sumatra region; in particular, we consider the case of a probable event releasing the strain left over from the 1833 rupture after the 2007 Bengkulu earthquake. While these studies are not carried to the full extent of run-up calculations at individual sites, they give a general estimate of expectable hazard, relative to 2004, under the relevant scenarios, at 17 offshore virtual gauges strategically located from Oman to South Africa. We confirm more quantitatively the results of Okal and Synolakis (2008), namely that the change of directivity characteristics results in an increase of tsunami amplitude (with respect to 2004) at all sites South of Kenya (including Madagascar and the Mascarenes), while amplitudes at the Horn of Africa (Socotra, Somalia) remain large, due to focusing by individual bathymetric features. In short, potential earthquake sources along the Southern coast of Sumatra could result in higher wave heights than in 2004, along most of the Eastern shores of Africa, Madagascar and the Mascarenes.

Synolakis, C. E.; Okal, E. A.; Fritz, H. M.; Sladen, A.

2008-12-01

100

Predicting natural catastrophes tsunamis  

CERN Multimedia

1. Tsunamis - Introduction - Definition of phenomenon - basic properties of the waves Propagation and dispersion Interaction with coasts - Geological and societal effects Origin of tsunamis - natural sources Scientific activities in connection with tsunamis. Ideas about simulations 2. Tsunami generation - The earthquake source - conventional theory The earthquake source - normal mode theory The landslide source Near-field observation - The Plafker index Far-field observation - Directivity 3. Tsunami warning - General ideas - History of efforts Mantle magnitudes and TREMOR algorithms The challenge of "tsunami earthquakes" Energy-moment ratios and slow earthquakes Implementation and the components of warning centers 4. Tsunami surveys - Principles and methodologies Fifteen years of field surveys and related milestones. Reconstructing historical tsunamis: eyewitnesses and geological evidence 5. Lessons from the 2004 Indonesian tsunami - Lessons in seismology Lessons in Geology The new technologies Lessons in civ...

CERN. Geneva

2005-01-01

 
 
 
 
101

A STUDY OF THE EFFECT OF PERMEABILITY OF ROCKS IN TSUNAMI GENERATION AND PROPAGATION BY SEISMIC FAULTING USING LINEARIZED SHALLOW – WATER WAVE THEORY  

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Full Text Available The effect of permeability of rocks inside the ocean on Tsunami generation and Propagation is investigated. We study the nature of Tsunami build up and propagation using realistic curvilinear source models. The models are used to study the effect of permeability on tsunami amplitude amplification as a function on spreading velocity and rise time. Effect of permeability on Tsunami waveforms within the frame of the linearized shallow water wave theory for constant water depth are analyzed analytically using Transform methods. It is observed that in the region of highly permeable rocks the tsunami wave run is fast in comparison to low permeable rocks. The amplitude as a function of the propagated uplift length and width are analyzed. The cases of Tsunami-2011 (Japan), Tsunami- 2006 (Srilanka), and Tsunami-2006 (Madras) have been demonstrated in the study.

PARUL SAXENA; LOKENDRA KUMAR

2012-01-01

102

A BRIEF HISTORY OF TSUNAMIS IN THE CARIBBEAN SEA  

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Full Text Available The area of the Caribbean Sea is geologically active. Earthquakes and volcanoes are common occurrences. These geologic events can generate powerful tsunamis some of which are more devastating than the earthquake or volcanic eruption itself. This document lists brief descriptions of 91 reported waves that might have been tsunamis within the Caribbean region. Of these, 27 are judged by the authors to be true, verified tsunamis and an additional nine are considered to be very likely true tsunamis. The additional 53 events either are not described with sufficient detail in the literature to verify their tsunami nature or are judged to be reports of other phenomenasuch as sea quakes or hurricane storm surges which may have been reported as tsunamis. Included in these 91 reports are teletsunamis, tectonic tsunamis, landslide tsunamis, and volcanic tsunamis that have caused major damage and deaths. Nevertheless, in recent history these events have been relatively rare. In the interim since the last major tsunami event in the Caribbean Sea the coastal regions have greatly increased in population. Coastal development has also increased. Today tourism is a major industry that exposes thousands of non-residents to the disastrous effects of a tsunami. These factors make the islands in this region much more vulnerable today than they were when the last major tsunami occurred in this area. This paper gives an overview of the tsunami history in the area. This history illustrates what can be expected in the future from this geologic hazard and provides information that will be useful for mitigation purposes.

James F. Lander; LowellS. Whiteside; Patricia A. Lockridge

2002-01-01

103

Tsunami Preparedness  

Science.gov (United States)

... Disaster or Emergency › Types of Emergency › Tsunami Preparedness Tsunami Preparedness About About Tsunami Tsunamis are a series of large ocean waves ... night. Be aware of the signs of a tsunami: A strong earthquake lasting 20 seconds or more ...

104

Lessons Learned from the 2011 Great East Japan Tsunami: Performance of Tsunami Countermeasures, Coastal Buildings, and Tsunami Evacuation in Japan  

Science.gov (United States)

In 2011, Japan was hit by a tsunami that was generated by the greatest earthquake in its history. The first tsunami warning was announced 3 min after the earthquake, as is normal, but failed to estimate the actual tsunami height. Most of the structural countermeasures were not designed for the huge tsunami that was generated by the magnitude M = 9.0 earthquake; as a result, many were destroyed and did not stop the tsunami. These structures included breakwaters, seawalls, water gates, and control forests. In this paper we discuss the performance of these countermeasures, and the mechanisms by which they were damaged; we also discuss damage to residential houses, commercial and public buildings, and evacuation buildings. Some topics regarding tsunami awareness and mitigation are discussed. The failures of structural defenses are a reminder that structural (hard) measures alone were not sufficient to protect people and buildings from a major disaster such as this. These defenses might be able to reduce the impact but should be designed so that they can survive even if the tsunami flows over them. Coastal residents should also understand the function and limit of the hard measures. For this purpose, non-structural (soft) measures, for example experience and awareness, are very important for promoting rapid evacuation in the event of a tsunami. An adequate communication system for tsunami warning messages and more evacuation shelters with evacuation routes in good condition might support a safe evacuation process. The combination of both hard and soft measures is very important for reducing the loss caused by a major tsunami. This tsunami has taught us that natural disasters can occur repeatedly and that their scale is sometimes larger than expected.

Suppasri, Anawat; Shuto, Nobuo; Imamura, Fumihiko; Koshimura, Shunichi; Mas, Erick; Yalciner, Ahmet Cevdet

2013-06-01

105

3D numerical investigation on landslide generated tsunamis around a conical island  

Science.gov (United States)

This paper presents numerical computations of tsunamis generated by subaerial and submerged landslides falling along the flank of a conical island. The study is inspired by the tsunamis that on 30th December 2002 attacked the coast of the volcanic island of Stromboli (South Tyrrhenian sea, Italy). In particular this paper analyzes the important feature of the lateral spreading of landside generated tsunamis and the associated flooding hazard. The numerical model used in this study is the full three dimensional commercial code FLOW-3D. The model has already been successfully used (Choi et al., 2007; 2008; Chopakatla et al, 2008) to study the interaction of waves and structures. In the simulations carried out in this work a particular feature of the code has been employed: the GMO (General Moving Object) algorithm. It allows to reproduce the interaction between moving objects, as a landslide, and the water. FLOW-3D has been firstly validated using available 3D experiments reproducing tsunamis generated by landslides at the flank of a conical island. The experiments have been carried out in the LIC laboratory of the Polytechnic of Bari, Italy (Di Risio et al., 2009). Numerical and experimental time series of run-up and sea level recorded at gauges located at the flanks of the island and offshore have been successfully compared. This analysis shows that the model can accurately represent the generation, the propagation and the inundation of landslide generated tsunamis and suggests the use of the numerical model as a tool for preparing inundation maps. At the conference we will present the validation of the model and parametric analyses aimed to investigate how wave properties depend on the landslide kinematic and on further parameters such as the landslide volume and shape, as well as the radius of the island. The expected final results of the research are precomputed inundation maps that depend on the characteristics of the landslide and of the island. Finally we will try to apply the code to a real life case i.e. the landslide tsunamis at the coast of the Stromboli island (Italy). SELECTED REFERENCES Choi, B.H. and D. C. Kim and E. Pelinovsky and S. B. Woo, 2007. Three dimensional simulation of tsunami run-up around conical island. Coastal Engineering 54,374 pp. 618-629. Chopakatla, S.C. and T.C. Lipmann and J.E. Richardson, 2008. Field verification of a computational fluid dynamics model for wave transformation and breaking in the surf zone. Journal of Waterway, Port, Coastal, and Ocean Engineering 134(2), pp. 71-80 Di Risio, M., P. De Girolamo, G. Bellotti, A. Panizzo, F. Aristodemo, M. G.Molfetta, and A. F. Petrillo (2009), Landslidegenerated tsunamis runup at the coast of a conical island: New physical model experiments. J. Geophys. Res., 114, C01009, doi:10.1029/2008JC004858 Flow Science, Inc, 2007. FLOW-3D User's Manual.

Montagna, Francesca; Bellotti, Giorgio

2010-05-01

106

2011 Tsunami Propagation  

Science.gov (United States)

This activity uses data collected from DART (Deep-ocean Assessment and Reporting of Tsunamis) stations in the Pacific following the 2011 tsunami generated off the coast of Japan. Students are required to map the wave front after 5, 10, and 15 hours to better understand the speed and propagation of the tsunami wave.

Martin, Julie

107

Tsunami Propagation Visualization  

Science.gov (United States)

This visualization of the Tsunami generated by the 2010 Chile earthquake shows the spread of the tsunami waves across the pacific. The animation was computed with the MOST tsunami model. Across the bottom of the visualization is a comparison of the MOST predictions to actual data collected by a sensor buoy (denoted by the solid yellow square on the map).

Research, Noaa C.

108

Landslide tsunami hazard in the Indonesian Sunda Arc  

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Full Text Available The Indonesian archipelago is known for the occurrence of catastrophic earthquake-generated tsunamis along the Sunda Arc. The tsunami hazard associated with submarine landslides however has not been fully addressed. In this paper, we compile the known tsunamigenic events where landslide involvement is certain and summarize the properties of published landslides that were identified with geophysical methods. We depict novel mass movements, found in newly available bathymetry, and determine their key parameters. Using numerical modeling, we compute possible tsunami scenarios. Furthermore, we propose a way of identifying landslide tsunamis using an array of few buoys with bottom pressure units.

S. Brune; A. Y. Babeyko; S. Ladage; S. V. Sobolev

2010-01-01

109

Modeling of Tsunami Generation and Propagation by a Spreading Curvilinear Seismic Faulting in Linearized Shallow-Water Wave Theory  

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Full Text Available The processes of tsunami evolution during its generation in search for possible amplification mechanisms resulting from unilateral spreading of the sea floor uplift is investigated. We study the nature of the tsunami build up and propagation during and after realistic curvilinear source models represented by a slowly uplift faulting and a spreading slip-fault model. The models are used to study the tsunami amplitude amplification as a function of the spreading velocity and rise time. Tsunami waveforms within the frame of the linearized shallow water theory for constant water depth are analyzed analytically by transform methods (Laplace in time and Fourier in space) for the movable source models. We analyzed the normalized peak amplitude as a function of the propagated uplift length, width and the average depth of the ocean along the propagation path.

Hossam S. Hassan; Khaled T. Ramadan; Sarwat N. Hanna

2010-01-01

110

The VOLNA code for the numerical modelling of tsunami waves: generation, propagation and inundation  

CERN Multimedia

A novel tool for tsunami wave modelling is presented. This tool has the potential of being used for operational purposes: indeed, the numerical VOLNA code is able to handle the complete life-cycle of a tsunami (generation, propagation and run-up along the coast). The algorithm works on unstructured triangular meshes and, thus, can be run in arbitrary complex domains. It is often the case since natural coasts tend to be of fractal shape [Sapoval et al, 2004]. This paper contains the detailed description of the finite volume scheme implemented in the code. We explain the numerical treatment of the wet/dry transition. This point is crucial for accurate run-up computation. Most existing tsunami codes use semi-empirical techniques at this stage, which are not always sufficient. The main reason is that people evacuation is decided on the base of inundation maps which are produced with this type of numerical tools. Finally we present several realistic test cases that partially validate our algorithm. Comparisons wit...

Dutykh, Denys; Dias, Frédéric

2010-01-01

111

International year of planet earth 7. Oceans, submarine land-slides and consequent tsunamis in Canada  

Science.gov (United States)

Canada has the longest coastline and largest continental margin of any nation in the World. As a result, it is more likely than other nations to experience marine geohazards such as submarine landslides and consequent tsunamis. Coastal landslides represent a specific threat because of their possible proximity to societal infrastructure and high tsunami potential; they occur without warning and with little time lag between failure and tsunami impact. Continental margin landslides are common in the geologic record but rare on human timescales. Some ancient submarine landslides are massive but more recent events indicate that even relatively small slides on continental margins can generate devastating tsunamis. Tsunami impact can occur hundreds of km away from the source event, and with less than 2 hours warning. Identification of high-potential submarine landslide regions, combined with an understanding of landslide and tsunami processes and sophisticated tsunami propagation models, are required to identify areas at high risk of impact.

Mosher, D. C.

2009-01-01

112

The Tsunami Triggered by the El Asnam (Algeria) Earthquake of 1980: a New Hypothesis of Generation  

Science.gov (United States)

On the 10th of October 1980, a Mw=7.1 earthquake destroyed the town of El Asnam (actual Ech Cheliff, Northern Algeria) causing several thousands of casualties and leading to considerable economic losses for Algeria. This is the biggest instrumentally recorded earthquake in Africa. A lot of measurement campaigns have been immediately set up in order to constrain the fault rupture mechanisms principally using the numerous aftershocks. Then these studies furnish important information concerning principally the focal mechanisms in this area, the length and width of the rupture zone, the depth and the coseismic slip. But although the epicenter has been located about 45 km from the sea, and 15 km east of El Asnam, in the same area of the 1954 Orléansville earthquake (Mw=6.6), it is known to have triggered a small tsunami which was able to reach the south-eastern Spanish Coast in several locations where it has been recorded on tide gages. Thus six maregrams are available from Alicante to Algeciras Several previous studies present this tsunami as the result of a submarine mass failure as the 1954 event which led to the rupture of submarine phone cables. In this work we propose a rupture scenario based on previous studies results as geodetic measurements of vertical movements, aftershocks localization, focal mechanisms determination and identification of geological features among other things. We show that the seismic initial deformation itself, using Okada’s formulae, is able to disturb the sea surface near the Algerian Coast by several centimeters, even at this distance from the epicenter, and propagate a tsunami wave toward the Spanish Coast. The results are compared with historical records in terms of arrival times, polarity and wave amplitudes and discussed, especially concerning the integration of such inland earthquake in the catalog of the future Western Mediterranean Tsunami Warning System. This study was partially funded by the European project TRANSFER which aimed at constraining tsunamigenic sources and hazard zones in Mediterranean Sea more particularly, and by the French ANR project MAREMOTI under contract ANR-08-RISKNAT-05-01c which aims to assess the tsunami hazard for the French Territories.

Roger, J.; Hebert, H.; Briole, P.

2009-12-01

113

MODELING THE ASIAN TSUNAMI EVOLUTION AND PROPAGATION WITH A NEW GENERATION MECHANISM AND A NON-LINEAR DISPERSIVE WAVE MODEL  

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Full Text Available A common approach in modeling the generation and propagation of tsunami is based on the assumption of a kinematic vertical displacement of ocean water that is analogous to the ocean bottom displacement during a submarine earthquake and the use of a non-dispersive long-wave model to simulate its physical transformation as it radiates outward from the source region. In this study, a new generation mechanism and the use of a highly-dispersive wave model to simulate tsunami inception, propagation and transformation are proposed. The new generation model assumes that transient ground motion during the earthquake can accelerate horizontal currents with opposing directions near the fault line whose successive convergence and divergence generate a series of potentially destructive oceanic waves. The new dynamic model incorporates the effects of earthquake moment magnitude, ocean compressibility through the buoyancy frequency, the effects of focal and water depths, and the orientation of ruptured fault line in the tsunami magnitude and directivity.For tsunami wave simulation, the nonlinear momentum-based wave model includes important wave propagation and transformation mechanisms such as refraction, diffraction, shoaling, partial reflection and transmission, back-scattering, frequency dispersion, and resonant wave-wave interaction. Using this model and a coarse-resolution bathymetry, the new mechanism is tested for the Indian Ocean tsunami of December 26, 2004. A new flooding and drying algorithm that consider waves coming from every direction is also proposed for simulation of inundation of low-lying coastal regions.It is shown in the present study that with the proposed generation model, the observed features of the Asian tsunami such as the initial drying of areas east of the source region and the initial flooding of western coasts are correctly simulated. The formation of a series of tsunami waves with periods and lengths comparable to observations are also well simulated with the new generation model. Furthermore, the shoaling behavior of the tsunami waves during flooding of dry land was also simulated by the new run-up algorithm. Finally, the new generation and propagation models can explain the combined and independent effects of various factors in tsunami generation and transformation taking into consideration the properties of the ocean and the geologic disturbance.

Paul C. Rivera

2006-01-01

114

Tsunami Awareness  

Medline Plus

Full Text Available ... Tsunami Hazard Mitigation Program NOAA Center for Tsunami Research Credits: NOAA National Weather Service NOAA National Ocean ... Tsunami Hazard Mitigration Program NOAA Center for Tsunami Research Rebel Arts Please copy and paste the ...

115

Generation and Propagation of Tsunami by a Moving Realistic Curvilinear Slide Shape with Variable Velocities in Linearized Shallow-Water Wave Theory  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The process of tsunami evolution during its generation under the effect of the variable velocities of realistic submarine landslides based on a two-dimensional curvilinear slide model is investigated. Tsunami generation from submarine gravity mass flows is described in three stages. The first stage ...

Hossam Shawky Hassan; Khaled Tawfik Ramadan; Sarwat Nageeb Hanna

116

Numerical study of tsunami generated by multiple submarine slope failures in Resurrection Bay, Alaska, during the MW 9.2 1964 earthquake  

Science.gov (United States)

We use a viscous slide model of Jiang and LeBlond (1994) coupled with nonlinear shallow water equations to study tsunami waves in Resurrection Bay, in south-central Alaska. The town of Seward, located at the head of Resurrection Bay, was hit hard by both tectonic and local landslide-generated tsunami waves during the MW 9.2 1964 earthquake with an epicenter located about 150 km northeast of Seward. Recent studies have estimated the total volume of underwater slide material that moved in Resurrection Bay during the earthquake to be about 211 million m3. Resurrection Bay is a glacial fjord with large tidal ranges and sediments accumulating on steep underwater slopes at a high rate. Also, it is located in a seismically active region above the Aleutian megathrust. All these factors make the town vulnerable to locally generated waves produced by underwater slope failures. Therefore it is crucial to assess the tsunami hazard related to local landslide-generated tsunamis in Resurrection Bay in order to conduct comprehensive tsunami inundation mapping at Seward. We use numerical modeling to recreate the landslides and tsunami waves of the 1964 earthquake to test the hypothesis that the local tsunami in Resurrection Bay has been produced by a number of different slope failures. We find that numerical results are in good agreement with the observational data, and the model could be employed to evaluate landslide tsunami hazard in Alaska fjords for the purposes of tsunami hazard mitigation. ?? Birkh??user Verlag, Basel 2009.

Suleimani, E.; Hansen, R.; Haeussler, P. J.

2009-01-01

117

Tsunamigenic Ratio of the Pacific Ocean earthquakes and a proposal for a Tsunami Index  

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Full Text Available The Pacific Ocean is the location where two-thirds of tsunamis have occurred, resulting in a great number of casualties. Once information on an earthquake has been issued, it is important to understand if there is a tsunami generation risk in relation with a specific earthquake magnitude or focal depth. This study proposes a Tsunamigenic Ratio (TR) that is defined as the ratio between the number of earthquake-generated tsunamis and the total number of earthquakes. Earthquake and tsunami data used in this study were selected from a database containing tsunamigenic earthquakes from prior 1900 to 2011. The TR is calculated from earthquake events with a magnitude greater than 5.0, a focal depth shallower than 200 km and a sea depth less than 7 km. The results suggest that a great earthquake magnitude and a shallow focal depth have a high potential to generate tsunamis with a large tsunami height. The average TR in the Pacific Ocean is 0.4, whereas the TR for specific regions of the Pacific Ocean varies from 0.3 to 0.7. The TR calculated for each region shows the relationship between three influential parameters: earthquake magnitude, focal depth and sea depth. The three parameters were combined and proposed as a dimensionless parameter called the Tsunami Index (TI). TI can express better relationship with the TR and with maximum tsunami height, while the three parameters mentioned above cannot. The results show that recent submarine earthquakes had a higher potential to generate a tsunami with a larger tsunami height than during the last century. A tsunami is definitely generated if the TI is larger than 7.0. The proposed TR and TI will help ascertain the tsunami generation risk of each earthquake event based on a statistical analysis of the historical data and could be an important decision support tool during the early tsunami warning stage.

A. Suppasri; F. Imamura; S. Koshimura

2012-01-01

118

ALGERIA’S VULNERABILITY TO TSUNAMIS FROM NEAR-FIELD SEISMIC SOURCES  

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Full Text Available Evaluation of the effects of tsunami damage relative to earthquake damage may help to identify critical coastal zone structures and exposed populations for near field tsunami risk. In this work, we propose to define the ratio between tsunami intensity and earthquake intensity as a measure of near field tsunami vulnerability for coastal communities. This parameter is estimated for 13 tsunami events reported in North Algeria from the 14th century to present. Although the results show that there are no tsunamis that are unusually large for the size of the earthquake that generated them, coastal communities remain at risk from these periodic hazards.We also use tsunami modelling and published information to estimate maximum inundation in Northern Algeria. Then, we generate a flooding map, which reveals the communities, buildings and infrastructure that are exposed to the tsunami hazard. This map shows that the majority of the people in Algiers and Oran live above 5 meters in elevation, and are hence not exposed to the hazard. Despite this, the coastline remains vulnerable to tsunami as earthquakes can damage poorly constructed buildings and other infrastructure, weakening it prior to the arrival of the tsunami. To increase resilience in the coastal zone, tsunami and earthquake awareness, education and preparedness must become a priority in the context of regional early warning programs.

ALGERIA’S VULNERABILITY TO TSUNAMIS FROM NEAR-FIELD SEISMIC SOURCES; A. Cisternas; J. -L. Vigneresse; W. Dudley; B. Mc Adoo

2012-01-01

119

Tsunamis and meteorological tsunamis: similarities and differences  

Science.gov (United States)

Destructive seiche oscillations occasionally generated in certain bays and inlets are mainly associated with two natural forcing phenomena: Seismic activity (tsunamis), and atmospheric disturbances (meteotsunamis). Despite their different origin, both types are modified and amplified by topography in a similar way and produce similar catastrophic effects in coastal areas. Due to these similarities, it is often difficult to distinguish between these two phenomena without knowing the exact source characteristics. Recognition and separation of these phenomena is important for the revision/improvement of existing tsunami catalogues but also to better understand the generation mechanism and mitigate their possible catastrophic effects. To investigate this problem and to compare seismic and meteorological tsunamis, we assembled a number of cases when both phenomena had been recorded at the same place. In particular, our findings included Alicante (Mediterranean coast of Spain), Malokurilsk and Krabovaya bays (Shikotan Island, Russia), and Tofino, Winter Harbour, Bamfield, Port Hardy, and Victoria (British Columbia, Canada). We also used the results of the LAST-97 hydrophysical experiment when eight bottom pressure stations were deployed on the shelf and in the inlets of Menorca Island (Western Meditterranean, Spain) and three precise microbarographs were working on the coast. Our analysis is based on the assumption that both tsunamis and meteotsunamis are formed by the combined effects of external forcing and topography. So, for different events recorded at the same site, the similarities are related to topography and the differences to the forcing. On the contrary, for the same event recorded at different stations, similarities are mainly associated with the forcing and the differences with specific local topographic features. Analysis of the spectral distributions and comparison with background noise enabled us to reconstruct the topographic transfer functions for all stations, estimate (for certain stations) the relative influence of shelf and bay/inlets, and to determine the sources. The estimated source functions for long waves associated with seismic events were found to have typical periods of 10-40 min, while those generated by a storm had shorter periods and strong energy pumping from high-frequencies due to non-linear interaction of wind waves.

Rabinovich, A. B.; Monserrat, S.

2003-04-01

120

Tsunami hazard scenarios in the Adriatic Sea domain  

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Full Text Available The tsunami phenomenon is mainly detected in oceanic domains but it can also occur in small basins as the Adriatic Sea. The presence of great waves has been recorded a few times in the past centuries on the Adriatic shorelines, therefore this suggests the idea to evaluate which could be the maximum amplitude reached by a possible future tsunami event. In this framework we calculate several synthetic mareograms applying to the shallow water basin case both the theory of modal summation by Panza et al. (2000) and the theory of the Green's function by Yanovskaya et al. (2003). The first is applied to the case of tsunamis generated by an offshore source, the second to the case of tsunamis generated by an inland source. Both kinds of tsunamigenic events did already occur in the Adriatic domain, as witnessed in many catalogues (Caputo and Faita, 1984; Bedosti and Caputo, 1986; Tinti et al., 2004) and also pointed out in the recent "Catalogue of reported tsunami events in the Adriatic Sea" (see Appendix). We calculate synthetic mareograms varying those parameters which are the most influencing in tsunami generation, such as magnitude, focal depth, water layer thickness, etc., in order to estimate the expected values of tsunami maximum amplitude and arrival time, in the whole Adriatic basin, for the selected scenarios.

M. Paulatto; T. Pinat; F. Romanelli

2007-01-01

 
 
 
 
121

Analytical Solutions for Tsunami Waves Generated by Submarine Landslides in Narrow Bays and Channels  

Science.gov (United States)

Analytical theory of tsunami wave generation by submarine landslides is extended to the case of narrow bays and channels of different geometry, in the shallow-water theory framework. New analytical solutions are obtained. For a number of bottom configurations, the wave field can be found explicitly in the form of the Duhamel integral. It is described by three waves: one forced wave propagating together with the landslide and two free waves propagating in opposite directions. The cases for bays with triangular (V-shaped bay), parabolic (U-shaped bay), and rectangular cross-sections are discussed in detail. The dynamics of the offshore-propagating wave in linearly inclined bays of different cross-section are also studied asymptotically for the resonant moving landslide. Different cases of landslides of increasing and decreasing volume are considered. It is shown that even if the landslide is moving under fully resonant conditions, the amplitude of the propagating tsunami wave may still be bounded, depending on the type of the landslide.

Didenkulova, Ira; Pelinovsky, Efim

2013-09-01

122

Sediment transport on the inner shelf off Khao Lak (Andaman Sea, Thailand) during the 2004 Indian Ocean tsunami and former storm events: evidence from foraminiferal transfer functions  

Science.gov (United States)

We have investigated the benthic foraminiferal fauna from sediment event layers associated with the 2004 Indian Ocean tsunami and former storms, that have been retrieved in short sediment cores from offshore environments of the Andaman Sea, off Khao Lak, western Thailand. Species composition and test preservation of the benthic foraminiferal faunas exhibit pronounced changes across the studied sections and provide information on the depositional history of the tsunami layer, particularly on the source water depth of the displaced foraminiferal tests. In order to obtain accurate bathymetric information on sediment provenance, we have mapped the distribution of modern faunas in non-tsunamigenic surface sediments and created a calibration data set for the development of a transfer function. Our quantitative reconstructions revealed that the re-suspension of sediment particles by the tsunami wave was restricted to a maximum water depth of approximately 20 m. Similar values were obtained for former storm events, thus impeding an easy distinction of different high-energy events.

Milker, Y.; Wilken, M.; Schumann, J.; Sakuna, D.; Feldens, P.; Schwarzer, K.; Schmiedl, G.

2013-05-01

123

MadGraph/MadEvent : a multipurpose event generator  

International Nuclear Information System (INIS)

[en] The MadGraph/MadEvent Monte Carlo event generator is presented. Particular attention is given to the features relevant to the study of photon-photon and photon-proton interactions at hadron colliders

2008-01-01

124

Boussinesq systems in two space dimensions over a variable bottom for the generation and propagation of tsunami waves  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Considered here are Boussinesq systems of equations of surface water wave theory over a variable bottom. A simplified such Boussinesq system is derived and solved numerically by the standard Galerkin-finite element method. We study by numerical means the generation of tsunami waves due to bottom def...

Mitsotakis, Dimitrios

125

Building Damage and Business Continuity Management in the Event of Natural Hazards: Case Study of the 2004 Tsunami in Sri Lanka  

Directory of Open Access Journals (Sweden)

Full Text Available The Sumatra Earthquake and Indian Ocean Tsunami event on the 26 December 2004 has provided a unique and valuable opportunity to evaluate the performance of various structures, facilities and lifeline systems during the tsunami wave attacks. There are especially meaningful observations concerning the structural changes due to the tsunami forces, which open up a wide area of research to develop the mitigation procedure. The business restoration process of business companies in terms of buildings, facilities and lifelines have shown greater research interest. In this study, we investigated the restoration process of business sectors in East and South coastal region in Sri Lanka after the 2004 Indian Ocean Tsunami. A field survey was conducted in East and South coast of Sri Lanka, in order to study the affecting parameters to damage assessment in the restoration process of the business companies. The results of the questionnaire-based field survey are then compared with the statistical analysis results. Finally, the factors affecting the restoration process after the tsunami are identified. As a main conclusion, financial support could be the most important reason for delays in restoration. Moreover, it has been observed that the tsunami inundation level of higher than one meter may have had more effect concerning the damage to the structures and requires additional time for restoration than other areas.

Chandana Dinesh Parape; Chinthaka Premachandra; Masayuki Tamura; Abdul Bari; Ranjith Disanayake; Duminda Welikanna; Shengye Jin; Masami Sugiura

2013-01-01

126

Boulder Deposits on the Southern Spanish Atlantic Coast: Possible Evidence for the 1755 AD Lisbon Tsunami?  

Directory of Open Access Journals (Sweden)

Full Text Available Field evidence of visible tsunami impacts in Europe is scarce. This research focused on an analysis of large littoral debris and accompanying geomorphic features and their rela- tionship to a tsunami event at Cabo de Trafalgar, located on the southern Spanish Atlantic coast. Relative dating of weathering features as well as minor bioconstructive forms in the littoral zone suggest the Lisbon tsunami of 1755 AD as the event responsible for the large deposits described. This tsunami had run up heights of more than 19 m and was generated at the Gorringe Bank, located 500 km west off the Cape. Tsunami deposits at Cabo de Tra- falgar are the first boulder deposits identified on the southern Spanish Atlantic coast and are located approximately 250 km southeast of the Algarve coast (Portugal), where other geo- morphic evidence for the Lisbon tsunami has been reported.

Franziska Whelan; Dieter Kelletat

2005-01-01

127

Tsunami Awareness  

Medline Plus

Full Text Available ... the NOAA Web site This site NOAA home ocean news ocean life sci & tech discoveries about locations contribute subscribe resources faqs Home Ocean News Tsunami Awareness Tsunami Awareness Links: Tsunami.gov ...

128

On the moroccan tsunami catalogue  

Directory of Open Access Journals (Sweden)

Full Text Available A primary tool for regional tsunami hazard assessment is a reliable historical and instrumental catalogue of events. Morocco by its geographical situation, with two marine sides, stretching along the Atlantic coast to the west and along the Mediterranean coast to the north, is the country of Western Africa most exposed to the risk of tsunamis. Previous information on tsunami events affecting Morocco are included in the Iberian and/or the Mediterranean lists of tsunami events, as it is the case of the European GITEC Tsunami Catalogue, but there is a need to organize this information in a dataset and to assess the likelihood of claimed historical tsunamis in Morocco. Due to the fact that Moroccan sources are scarce, this compilation rely on historical documentation from neighbouring countries (Portugal and Spain) and so the compatibility between the new tsunami catalogue presented here and those that correspond to the same source areas is also discussed.

F. Kaabouben; M. A. Baptista; A. Iben Brahim; A. El Mouraouah; A. Toto

2009-01-01

129

Numerical simulation of a tsunami event during the 1996 volcanic eruption in Karymskoye lake, Kamchatka, Russia  

Directory of Open Access Journals (Sweden)

Full Text Available Karymskoye caldera lake is a nearly circular body of water with a diameter of approximately 4 km and a depth of up to 60 m. The sublacustrine, Surtseyan-type eruption in the lake on 2–3 January 1996 included a series of underwater explosions. A field survey conducted the following summer showed signs of tsunami wave runup around the entire coastline of the lake, with a maximum of 29 m runup at the north shore near the source of the eruption, and 2–5 m runup at locations on the east and south shore far away from the source. The tsunami has been simulated using the numerical long wave model COULWAVE, with input from reconstructed realistic pre-eruption bathymetry. The tsunami source was chosen as suggested by Le Mehaute (1971) and Mirchina and Pelinovsky (1988). The initial wave was prescribed by a parabolic shape depression with a radius of R=200 m, and a height of 23 m at the rim of the parabola. Simulations were conducted to show principle directions for wave propagation, wave speed and arrival time for the leading wave group at the shore, and the distribution of wave height throughout the lake. Estimated result for wave runup are of the same order of magnitude as field measurements, except near the source of the eruption and at a few locations where analysis show significant wave breaking.

T. Torsvik; R. Paris; I. Didenkulova; E. Pelinovsky; A. Belousov; M. Belousova

2010-01-01

130

Elegent -- an elastic event generator  

CERN Document Server

Although elastic scattering of nucleons may look like a simple process, it presents a long-lasting challenge for theory. Due to missing hard energy scale, the perturbative QCD can not be applied. Instead, many phenomenological/theoretical models have emerged. In this paper we present a unified implementation of some of the most prominent models in a C++ library, moreover extended to account for effects of the electromagnetic interaction. The library is complemented with a number of utilities. For instance, programs to sample many distributions of interest in four-momentum transfer squared, t, impact parameter, b, and collision energy sqrt(s). These distributions at ISR, SppS, RHIC, Tevatron and LHC energies are available for download from the project web site. Both in the form of ROOT files and PDF figures providing comparisons among the models. The package includes also a tool for Monte-Carlo generation of elastic scattering events, which can easily be embedded in any other program framework.

Kašpar, Jan

2013-01-01

131

Dispersion of tsunamis: does it really matter?  

Directory of Open Access Journals (Sweden)

Full Text Available This article focuses on the effect of dispersion in the field of tsunami modeling. Frequency dispersion in the linear long-wave limit is first briefly discussed from a theoretical point of view. A single parameter, denoted as "dispersion time", for the integrated effect of frequency dispersion is identified. This parameter depends on the wavelength, the water depth during propagation, and the propagation distance or time. Also the role of long-time asymptotes is discussed in this context. The wave generation by the two main tsunami sources, namely earthquakes and landslides, are briefly discussed with formulas for the surface response to the bottom sources. Dispersive effects are then exemplified through a semi-idealized study of a moderate-strength inverse thrust fault. Emphasis is put on the directivity, the role of the "dispersion time", the significance of the Boussinesq model employed (dispersive effect), and the effects of the transfer from bottom sources to initial surface elevation. Finally, the experience from a series of case studies, including earthquake- and landslide-generated tsunamis, is presented. The examples are taken from both historical (e.g. the 2011 Japan tsunami and the 2004 Indian Ocean tsunami) and potential tsunamis (e.g. the tsunami after the potential La Palma volcanic flank collapse). Attention is mainly given to the role of dispersion during propagation in the deep ocean and the way the accumulation of this effect relates to the "dispersion time". It turns out that this parameter is useful as a first indication as to when frequency dispersion is important, even though ambiguity with respect to the definition of the wavelength may be a problem for complex cases. Tsunamis from most landslides and moderate earthquakes tend to display dispersive behavior, at least in some directions. On the other hand, for the mega events of the last decade dispersion during deep water propagation is mostly noticeable for transoceanic propagation.

S. Glimsdal; G. K. Pedersen; C. B. Harbitz; F. Løvholt

2013-01-01

132

Dispersion of tsunamis: does it really matter?  

Science.gov (United States)

This article focuses on the effect of dispersion in the field of tsunami modeling. Frequency dispersion in the linear long-wave limit is first briefly discussed from a theoretical point of view. A single parameter, denoted as "dispersion time", for the integrated effect of frequency dispersion is identified. This parameter depends on the wavelength, the water depth during propagation, and the propagation distance or time. Also the role of long-time asymptotes is discussed in this context. The wave generation by the two main tsunami sources, namely earthquakes and landslides, are briefly discussed with formulas for the surface response to the bottom sources. Dispersive effects are then exemplified through a semi-idealized study of a moderate-strength inverse thrust fault. Emphasis is put on the directivity, the role of the "dispersion time", the significance of the Boussinesq model employed (dispersive effect), and the effects of the transfer from bottom sources to initial surface elevation. Finally, the experience from a series of case studies, including earthquake- and landslide-generated tsunamis, is presented. The examples are taken from both historical (e.g. the 2011 Japan tsunami and the 2004 Indian Ocean tsunami) and potential tsunamis (e.g. the tsunami after the potential La Palma volcanic flank collapse). Attention is mainly given to the role of dispersion during propagation in the deep ocean and the way the accumulation of this effect relates to the "dispersion time". It turns out that this parameter is useful as a first indication as to when frequency dispersion is important, even though ambiguity with respect to the definition of the wavelength may be a problem for complex cases. Tsunamis from most landslides and moderate earthquakes tend to display dispersive behavior, at least in some directions. On the other hand, for the mega events of the last decade dispersion during deep water propagation is mostly noticeable for transoceanic propagation.

Glimsdal, S.; Pedersen, G. K.; Harbitz, C. B.; Løvholt, F.

2013-06-01

133

Tsunamis from nature to physics  

Energy Technology Data Exchange (ETDEWEB)

Tsunamis are gravity waves that propagate near the ocean surface. They belong to the same family as common sea waves that we enjoy at the beach; however, tsunamis are distinct in their mode of generation and in their characteristic period, wavelength, and velocity. The type of tsunamis that induce widespread damage number about one or two per decade. Thus 'killer tsunamis' although fearful, are a relatively rare phenomenon.

Helal, M.A. [Department of Mathematics, Faculty of Science, University of Cairo, Giza, Cairo (Egypt)], E-mail: mahelal@yahoo.com; Mehanna, M.S. [Department of Mathematics, Faculty of Science, University of Cairo, Giza, Cairo (Egypt)

2008-05-15

134

Tsunamis from nature to physics  

International Nuclear Information System (INIS)

Tsunamis are gravity waves that propagate near the ocean surface. They belong to the same family as common sea waves that we enjoy at the beach; however, tsunamis are distinct in their mode of generation and in their characteristic period, wavelength, and velocity. The type of tsunamis that induce widespread damage number about one or two per decade. Thus 'killer tsunamis' although fearful, are a relatively rare phenomenon.

2008-01-01

135

Performance of coastal sea-defense infrastructure at El Jadida (Morocco) against tsunami threat: lessons learned from the Japanese 11 March 2011 tsunami  

Science.gov (United States)

This paper seeks to investigate the effectiveness of sea-defense structures in preventing/reducing the tsunami overtopping as well as evaluating the resulting tsunami impact at El Jadida, Morocco. Different tsunami wave conditions are generated by considering various earthquake scenarios of magnitudes ranging from Mw = 8.0 to Mw = 8.6. These scenarios represent the main active earthquake faults in the SW Iberia margin and are consistent with two past events that generated tsunamis along the Atlantic coast of Morocco. The behaviour of incident tsunami waves when interacting with coastal infrastructures is analysed on the basis of numerical simulations of near-shore tsunami waves' propagation. Tsunami impact at the affected site is assessed through computing inundation and current velocity using a high-resolution digital terrain model that incorporates bathymetric, topographic and coastal structures data. Results, in terms of near-shore tsunami propagation snapshots, waves' interaction with coastal barriers, and spatial distributions of flow depths and speeds, are presented and discussed in light of what was observed during the 2011 Tohoku-oki tsunami. Predicted results show different levels of impact that different tsunami wave conditions could generate in the region. Existing coastal barriers around the El Jadida harbour succeeded in reflecting relatively small waves generated by some scenarios, but failed in preventing the overtopping caused by waves from others. Considering the scenario highly impacting the El Jadida coast, significant inundations are computed at the sandy beach and unprotected areas. The modelled dramatic tsunami impact in the region shows the need for additional tsunami standards not only for sea-defense structures but also for the coastal dwellings and houses to provide potential in-place evacuation.

Omira, R.; Baptista, M. A.; Leone, F.; Matias, L.; Mellas, S.; Zourarah, B.; Miranda, J. M.; Carrilho, F.; Cherel, J.-P.

2013-07-01

136

Once and Future Tsunamis  

Science.gov (United States)

Long before the devastating December 2004 Indian Ocean event, tsunamis had already been implicated in the widespread death and destruction in Java and Sumatra following the 1883 eruption of Krakatoa. Tsunamis are also blamed for the collapse of the ancient Minoan civilization on Crete. These waves are capable of overrunning almost any coastline in the world and exacting a serious toll on both property and life. This interactive world map lets users explore key tsunamis dating from 3.5 billion years ago, along with a hypothetical future event that might take place in the Atlantic Ocean near the Canary Islands.

2011-04-29

137

Manifestation of the 2011 Great Tohoku Tsunami on the Coast of the Kuril Islands: A Tsunami with Ice  

Science.gov (United States)

The tsunami generated by the 2011 Tohoku Earthquake ( M w = 9.0) reached maximum heights of about 5 m along the coast of the Kuril Islands. The most essential feature of this event was sea ice about 0.5 m thick moved by the ocean water. The tsunami did not cause any essential damage on the Kuril Islands, but significantly affected coastal zones and produced interesting effects. The problem of a tsunami accompanied by marine ice is discussed and illustrated with photos.

Kaistrenko, Victor; Razjigaeva, Nadezhda; Kharlamov, Andrey; Shishkin, Alexander

2013-06-01

138

Tsunami and Earthquake Research at the USGS  

Science.gov (United States)

This portal provides access to information on United States Geological Survey (USGS) research and resources on tsunamis and earthquakes. Materials include news and events in USGS tsunami research, an overview of the program, and basic information on the life of a tsunami. There are also links to individual research projects. The site also features an extensive set of tsunami animations of real and hypothetical events, and links to VRML models of real and hypothetical events.

2011-07-20

139

Developing Tsunami fragility curves using remote sensing and survey data of the 2010 Chilean Tsunami in Dichato  

Directory of Open Access Journals (Sweden)

Full Text Available On 27 February 2010, a megathrust earthquake of Mw = 8.8 generated a destructive tsunami in Chile. It struck not only Chilean coast but propagated all the way to Japan. After the event occurred, the post-tsunami survey team was assembled, funded by the Japan Science and Technology Agency (JST), to survey the area severely affected by the tsunami. The tsunami damaged and destroyed numerous houses, especially in the town of Dichato. In order to estimate the structural fragility against tsunami hazard in this area, tsunami fragility curves were developed. Surveyed data of inundation depth and visual inspection of satellite images of Dichato were used to classify the damage to housing. A practical method suitable when there are limitations on available data for numerical simulation or damage evaluation from surveys is presented here. This study is the first application of tsunami fragility curves on the South American Pacific coast and it might be of practical use for communities with similar characteristics along the west Pacific coast. The proposed curve suggests that structures in Dichato will be severely damaged – with a 68% probability – already at 2 m tsunami inundation depth.

E. Mas; S. Koshimura; A. Suppasri; M. Matsuoka; M. Matsuyama; T. Yoshii; C. Jimenez; F. Yamazaki; F. Imamura

2012-01-01

140

World Data Center / National Geophysical Data Center's Tsunami Data Archive  

Science.gov (United States)

The WDC for Solid Earth Geophysics (including tsunamis) is operated by NOAA's National Geophysical Data Center (NGDC). NGDC is one of three environmental data centers within the National Environmental Satellite, Data and Information Service (NESDIS). Operating both World and National Data Centers, WDC/NGDC is now providing the long-term archive, data management, and access to national and global tsunami data for research and mitigation of tsunami hazards. Archive responsibilities include the global historic tsunami event and runup database, the bottom pressure recorder data, and access to event-specific tide-gauge data, as well as other related hazards and bathymetric data and information. The WDC/NGDC Worldwide Tsunami Database includes more than 2,400 events since 2,000 BC and more than 7,200 locations where tsunamis were observed. Times of generating earthquakes, tsunami arrival times, travel times, first motion of the wave, and wave periods are included in the database. The WDC/NGDC Worldwide Significant Earthquake Database includes information for more than 6,600 destructive earthquakes from 2,000 B.C. to the present. In the 1980s, NOAA's Pacific Marine Environmental Laboratory (PMEL) developed deep ocean tsunameters for the early detection, measurement, and real-time reporting of tsunamis in the open ocean. The tsunameters were developed by PMEL's Project DART (Deep-ocean Assessment and Reporting of Tsunamis). A DART system consists of a seafloor bottom pressure recording (BPR) system capable of detecting tsunamis as small as 1 cm, and a moored surface buoy for real-time communications. An acoustic link is used to transmit data from the BPR on the seafloor to the surface buoy. The data are then relayed via a GOES satellite link to ground stations for immediate dissemination to NOAA's Tsunami Warning Centers and PMEL. These systems were deployed near regions with a history of tsunami generation, to ensure measurement of the waves as they propagate towards threatened U.S. coastal communities and to acquire data critical to real-time forecasts. Currently, there are eight BPRs located near Alaska, Hawaii, Chili, and in the equatorial Pacific. The WDC/NGDC is now providing access to bottom pressure recorder (BPR) data from 1986 to the present. The BPR database includes pressure and temperature data from the ocean floor. All of the WDC/NGDC tsunami and significant earthquake databases are stored in a relational database management system. These data are accessible over the Web as tables, reports, interactive maps, and custom CD-ROMs.

Dunbar, P. K.; Brantley, K.; Stroker, K.

2005-12-01

 
 
 
 
141

NOAA/WEST COAST AND ALASKA TSUNAMI WARNING CENTER PACIFIC OCEAN RESPONSE CRITERIA  

Directory of Open Access Journals (Sweden)

Full Text Available New West Coast/Alaska Tsunami Warning Center (WCATWC) response criteria for earthquakes occurring in the Pacific basin are presented. Initial warning decisions are based on earthquake location, magnitude, depth, and - dependent on magnitude - either distance from source or pre- computed threat estimates generated from tsunami models. The new criteria will help limit the geographical extent of warnings and advisories to threatened regions, and complement the new operational tsunami product suite.Changes to the previous criteria include: adding hypocentral depth dependence, reducing geographical warning extent for the lower magnitude ranges, setting special criteria for areas not well-connected to the open ocean, basing warning extent on pre-computed threat levels versus tsunami travel time for very large events, including the new advisory product, using the advisory product for far-offshore events in the lower magnitude ranges, and specifying distances from the coast for on-shore events which may be tsunamigenic.This report sets a baseline for response criteria used by the WCATWC considering its processing and observational data capabilities as well as its organizational requirements. Criteria are set for tsunamis generated by earthquakes, which are by far the main cause of tsunami generation (either directly through sea floor displacement or indirectly by triggering of slumps). As further research and development provides better tsunami source definition, observational data streams, and improved analysis tools, the criteria will continue to adjust. Future lines of research and development capable of providing operational tsunami warning centers with better tools are discussed.

Paul Whitmore; Harley Benz; Maiclaire Bolton; George Crawford; Lori Dengler; Gerard Fryer; Jim Goltz; Roger Hansen; Kelli Kryzanowski; Steve Malone; David Oppenheime; Ervin Petty; Garry Rogers; Jay Wilson

2008-01-01

142

Tsunami: Un problema matemáticamente interesante Tsunami: An interesting mathematical problema  

Directory of Open Access Journals (Sweden)

Full Text Available Se presentan algunos aspectos fundamentales respecto a la matemática y la herramienta computacional que apoyan la compleja descripción del proceso físico tsunami desde dos enfoques específicos. En particular, se aborda analíticamente un modelo hidroelástico simple para el problema de generación de ondas tsunami, el cual permite obtener resultados en el área de ruptura. Por otra parte, el proceso de propagación de las ondas tsunami en el océano y el impacto a lo largo de la línea costera se analiza numéricamente utilizando el enfoque hidrodinámico, presentando en particular una aplicación directa sobre la predicción de tsunamis en México producidos por sismos potenciales en la trinchera Mesoamericana mediante el diseño de un “Módulo Sintetizador de Tsunamis” para simular tsunamis originados por sismos ocurridos en la zona de subducción de la costa occidental de México.We present some key aspects regarding the mathematics and the computational tool that support the complex description of the physical process tsunami from two specific approaches. In particular, it addresses analytically a simple hydroelastic model for the problem of tsunami wave generation, which provides results in the rupture area. Moreover, the propagation of tsunami waves in the ocean and the impact along the coastline is analyzed numerically using the hydrodynamic approach, presenting in particular a direct application to the prediction of tsunamis in Mexico caused by potential earthquakes in the Mesoamerican trench through the design of a “Tsunami Toolbox” to simulate tsunamis caused by earthquakes in the subduction zone on the western coast of Mexico.

Rodrigo González González; Modesto Ortiz Figueroa; José Miguel Montoya Rodríguez

2012-01-01

143

Simulation of the trans-oceanic tsunami propagation due to the 1883 Krakatau volcanic eruption  

Directory of Open Access Journals (Sweden)

Full Text Available The 1883 Krakatau volcanic eruption has generated a destructive tsunami higher than 40 m on the Indonesian coast where more than 36 000 lives were lost. Sea level oscillations related with this event have been reported on significant distances from the source in the Indian, Atlantic and Pacific Oceans. Evidence of many manifestations of the Krakatau tsunami was a subject of the intense discussion, and it was suggested that some of them are not related with the direct propagation of the tsunami waves from the Krakatau volcanic eruption. Present paper analyzes the hydrodynamic part of the Krakatau event in details. The worldwide propagation of the tsunami waves generated by the Krakatau volcanic eruption is studied numerically using two conventional models: ray tracing method and two-dimensional linear shallow-water model. The results of the numerical simulations are compared with available data of the tsunami registration.

B. H. Choi; E. Pelinovsky; K. O. Kim; J. S. Lee

2003-01-01

144

The MC++ event generator toolkit. Version 0  

Energy Technology Data Exchange (ETDEWEB)

We present a toolkit, written in the C++ programming language, for event generation in High Energy Physics. The toolkit, called MC++, is an attempt to formulate the event generation chain in high energy particle collisions in a transparent and generic way using object oriented programming techniques. (orig.).

Loennblad, L. (Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)); Nilsson, A. (Lund Univ. (Sweden). Dept. of Theoretical Physics)

1991-12-01

145

The MC++ event generator toolkit - version 0  

Energy Technology Data Exchange (ETDEWEB)

We present a toolkit, written in the C++ programming language, for event generation in high energy physics. The toolkit, called MC++, is an attempt to formulate the event generation chain in high energy particle collisions in a transparent and generic way using object oriented programming techniques. (orig.).

Loennblad, L. (Deutsches Elektronen Synchrotron - DESY, Hamburg (Germany)); Nilsson, A. (Lund Univ. (Sweden). Dept. of Theoretical Physics)

1992-08-01

146

Development of tsunami early warning systems and future challenges  

Directory of Open Access Journals (Sweden)

Full Text Available Fostered by and embedded in the general development of information and communications technology (ICT), the evolution of tsunami warning systems (TWS) shows a significant development from seismic-centred to multi-sensor system architectures using additional sensors (e.g. tide gauges and buoys) for the detection of tsunami waves in the ocean. Currently, the beginning implementation of regional tsunami warning infrastructures indicates a new phase in the development of TWS. A new generation of TWS should not only be able to realise multi-sensor monitoring for tsunami detection. Moreover, these systems have to be capable to form a collaborative communication infrastructure of distributed tsunami warning systems in order to implement regional, ocean-wide monitoring and warning strategies. In the context of the development of the German Indonesian Tsunami Early Warning System (GITEWS) and in the EU-funded FP6 project Distant Early Warning System (DEWS), a service platform for both sensor integration and warning dissemination has been newly developed and demonstrated. In particular, standards of the Open Geospatial Consortium (OGC) and the Organization for the Advancement of Structured Information Standards (OASIS) have been successfully incorporated. In the FP7 project Collaborative, Complex and Critical Decision-Support in Evolving Crises (TRIDEC), new developments in ICT (e.g. complex event processing (CEP) and event-driven architecture (EDA)) are used to extend the existing platform to realise a component-based technology framework for building distributed tsunami warning systems.

J. Wächter; A. Babeyko; J. Fleischer; R. Häner; M. Hammitzsch; A. Kloth; M. Lendholt

2012-01-01

147

Modeling of generation, propagation and runup of tsunami waves caused by oceanic impacts  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Die Modellierung von Bildung, Fortpflanzung und Auflaufen von impakt-generierten. Tsunami gibt Einsichten in die Bildungmechanismen dieser Wellen durch ozeanische Einschläge, ihre Fortpflanzung und ihr Auflaufen. Der SALE hydrocode wurde verwendet, um die Impaktprozesse zu simulieren. Ein neuentwic...

Weiß, Robert

148

Modeling the transport and accumulation floating debris generated by the 11 March 2011 Tohoku tsunami.  

UK PubMed Central (United Kingdom)

A global ocean circulation model is coupled to a particle-tracking model to simulate the transport of floating debris washed into the North Pacific Ocean by the Tohoku tsunami. A release scenario for the tsunami debris is based on coastal population and measured tsunami runup. Archived 2011/2012 hindcast current data is used to model the transport of debris since the tsunami, while data from 2008 to 2012 is used to investigate the distribution of debris on timescales up to 4years. The vast amount of debris pushed into ocean likely represents thousands of years worth of 'normal' litter flux from Japan's urbanized coastline. This is important since a significant fraction of the debris will be comprised of plastics, some of which will degrade into tiny particles and be consumed by marine organisms, thereby allowing adsorbed organic pollutants to enter our food supply in quantities much higher than present.

Lebreton LC; Borrero JC

2013-01-01

149

Modeling the transport and accumulation floating debris generated by the 11 March 2011 Tohoku tsunami.  

Science.gov (United States)

A global ocean circulation model is coupled to a particle-tracking model to simulate the transport of floating debris washed into the North Pacific Ocean by the Tohoku tsunami. A release scenario for the tsunami debris is based on coastal population and measured tsunami runup. Archived 2011/2012 hindcast current data is used to model the transport of debris since the tsunami, while data from 2008 to 2012 is used to investigate the distribution of debris on timescales up to 4years. The vast amount of debris pushed into ocean likely represents thousands of years worth of 'normal' litter flux from Japan's urbanized coastline. This is important since a significant fraction of the debris will be comprised of plastics, some of which will degrade into tiny particles and be consumed by marine organisms, thereby allowing adsorbed organic pollutants to enter our food supply in quantities much higher than present. PMID:23219397

Lebreton, Laurent C-M; Borrero, Jose C

2012-12-06

150

A mathematical model for Tsunami generation using a conservative velocity-pressure hyperbolic system  

CERN Multimedia

By using the Hugoniot curve in detonics as a Riemann invariant of a velocity-pressure model, we get a conservative hyperbolic system similar to the Euler equations. The only differences are the larger value of the adiabatic constant (= 8.678 instead of 1.4 for gas dynamics) and the mass density replaced by a strain density depending on the pressure. The model is not homogeneous since it involves a gravity and a friction term. After the seismic wave reaches up the bottom of the ocean, one gets a pressure wave propagating toward the surface, which is made of a frontal shock wave followed by a regular decreasing profile. Since this regular profile propagates faster than the frontal shock waves, the amplitude of the pressure wave is strongly reduced when reaching the surface. Only in the case of a strong earth tremor the residual pressure wave is still sufficient to generate a water elevation with a sufficient wavelengths enable to propagate as a SaintVenant water wave and to become a tsunami when reaching the sh...

Roux, Alain-Yves Le

2009-01-01

151

Tsunami waves generated by submarine landslides of variable volume: analytical solutions for a basin of variable depth  

Directory of Open Access Journals (Sweden)

Full Text Available Tsunami wave generation by submarine landslides of a variable volume in a basin of variable depth is studied within the shallow-water theory. The problem of landslide induced tsunami wave generation and propagation is studied analytically for two specific convex bottom profiles (h ~ x4/3 and h ~ x4). In these cases the basic equations can be reduced to the constant-coefficient wave equation with the forcing determined by the landslide motion. For certain conditions on the landslide characteristics (speed and volume per unit cross-section) the wave field can be described explicitly. It is represented by one forced wave propagating with the speed of the landslide and following its offshore direction, and two free waves propagating in opposite directions with the wave celerity. For the case of a near-resonant motion of the landslide along the power bottom profile h ~ x? the dynamics of the waves propagating offshore is studied using the asymptotic approach. If the landslide is moving in the fully resonant regime the explicit formula for the amplitude of the wave can be derived. It is demonstrated that generally tsunami wave amplitude varies non-monotonically with distance.

I. Didenkulova; I. Nikolkina; E. Pelinovsky; N. Zahibo

2010-01-01

152

Integrated warning system for tsunami and storm surges in China  

International Nuclear Information System (INIS)

Tsunami and storm surges result in unusual oscillation of seal level, flooding the coastal zones and constitute the major marine disasters in China. Damage by storm surges occurs frequently. According to statistics there are 14 storm surge events exceeding 1 every year on the average. Six of them are typhoon surges and the other eight are extra-tropical surges. In general, in China, there is one severe disaster of storm surge every two years. Monitoring, forecasting and warning for storm surges, including the drop of water level, are the major part of the operational oceanographic services in China. Such a warning system has been set up and is operated by the State Oceanic Administration since 1974. The results of the historical study of tsunami in the last few years pointed out that the anomaly of sea level generated by tele-tsunamis originating in the Pacific Ocean Basin is less than 30 cm on the mainland coast, but local tsunami in the China Seas can be very dangerous. For example, more than 50,000 people were killed by a tsunami in Taiwan and in Taiwan Strait in 1781. It resulted in more deaths than any other tsunami in recorded history. However, the frequency of tsunami disaster is very low for the coast of China, averaging only one every 100 years. It is impossible to set up an independent tsunami warning system in China. It is more practical to set up an integrated warning system on tsunami and on storm surges consisting of: A sea level observing network with real time sea level data acquisition capability; A monitoring system of weather causing the storm surges and of seismic stations monitoring tsunamigenic earthquakes; A tidal prediction scheme for operational use; A forecasting scheme for storm surges and tsunami analysis; The means for warning dissemination. (author). 8 refs, 4 figs, 3 tabs.

1989-01-01

153

Combined effects of tectonic and landslide-generated Tsunami Runup at Seward, Alaska during the Mw 9.2 1964 earthquake  

Science.gov (United States)

We apply a recently developed and validated numerical model of tsunami propagation and runup to study the inundation of Resurrection Bay and the town of Seward by the 1964 Alaska tsunami. Seward was hit by both tectonic and landslide-generated tsunami waves during the Mw 9.2 1964 mega thrust earthquake. The earthquake triggered a series of submarine mass failures around the fjord, which resulted in land sliding of part of the coastline into the water, along with the loss of the port facilities. These submarine mass failures generated local waves in the bay within 5 min of the beginning of strong ground motion. Recent studies estimate the total volume of underwater slide material that moved in Resurrection Bay to be about 211 million m3 (Haeussler et al. in Submarine mass movements and their consequences, pp 269-278, 2007). The first tectonic tsunami wave arrived in Resurrection Bay about 30 min after the main shock and was about the same height as the local landslide-generated waves. Our previous numerical study, which focused only on the local land slide generated waves in Resurrection Bay, demonstrated that they were produced by a number of different slope failures, and estimated relative contributions of different submarine slide complexes into tsunami amplitudes (Suleimani et al. in Pure Appl Geophys 166:131-152, 2009). This work extends the previous study by calculating tsunami inundation in Resurrection Bay caused by the combined impact of landslide-generated waves and the tectonic tsunami, and comparing the composite inundation area with observations. To simulate landslide tsunami runup in Seward, we use a viscous slide model of Jiang and LeBlond (J Phys Oceanogr 24(3):559-572, 1994) coupled with nonlinear shallow water equations. The input data set includes a high resolution multibeam bathymetry and LIDAR topography grid of Resurrection Bay, and an initial thickness of slide material based on pre- and post-earthquake bathymetry difference maps. For simulation of tectonic tsunami runup, we derive the 1964 coseismic deformations from detailed slip distribution in the rupture area, and use them as an initial condition for propagation of the tectonic tsunami. The numerical model employs nonlinear shallow water equations formulated for depth-averaged water fluxes, and calculates a temporal position of the shoreline using a free-surface moving boundary algorithm. We find that the calculated tsunami runup in Seward caused first by local submarine landslide-generated waves, and later by a tectonic tsunami, is in good agreement with observations of the inundation zone. The analysis of inundation caused by two different tsunami sources improves our understanding of their relative contributions, and supports tsunami risk mitigation in south-central Alaska. The record of the 1964 earthquake, tsunami, and submarine landslides, combined with the high-resolution topography and bathymetry of Resurrection Bay make it an ideal location for studying tectonic tsunamis in coastal regions susceptible to underwater landslides. ?? 2010 Springer Basel AG.

Suleimani, E.; Nicolsky, D. J.; Haeussler, P. J.; Hansen, R.

2011-01-01

154

MadEvent: automatic event generation with MadGraph  

International Nuclear Information System (INIS)

[en] We present a new multi-channel integration method and its implementation in the multi-purpose event generator MadEvent, which is based on MadGraph. Given a process, MadGraph automatically identifies all the relevant subprocesses, generates both the amplitudes and the mappings needed for an efficient integration over the phase space, and passes them to MadEvent. As a result, a process-specific, stand-alone code is produced that allows the user to calculate cross sections and produce unweighted events in a standard output format. Several examples are given for processes that are relevant for physics studies at present and forthcoming colliders. (author)

2003-01-01

155

Tsunami Hazard in Crescent City, California from Kuril Islands earthquakes  

Science.gov (United States)

On November 15, Crescent City in Del Norte County, California was hit by a series of tsunami surges generated by the M = 8.3 Kuril Islands earthquake causing an estimated 9.7 million (US dollars) in damages to the small boat basin. This was the first significant tsunami loss on US territory since the 1964 Alaska tsunami. The damage occurred nearly 8 hours after the official tsunami alert bulletins had been cancelled. The tsunami caused no flooding and did not exceed the ambient high tide level. All of the damage was caused by strong currents, estimated at 12 to 15 knots, causing the floating docks to be pinned against the pilings and water to flow over them. The event highlighted problems in warning criteria and communications for a marginal event with the potential for only localized impacts, the vulnerability of harbors from a relatively modest tsunami, and the particular exposure of the Crescent City harbor area to tsunamis. It also illustrated the poor understanding of local officials of the duration of tsunami hazard. As a result of the November tsunami, interim changes were made by WCATWC to address localized hazards in areas like Crescent City. On January 13, 2007 when a M = 8.1 earthquake occurred in the Kuril Islands, a formal procedure was in place for hourly conference calls between WCATWC, California State Office of Emergency Services officials, local weather Service Offices and local emergency officials, significantly improving the decision making process and the communication among the federal, state and local officials. Kuril Island tsunamis are relatively common at Crescent City. Since 1963, five tsunamis generated by Kuril Island earthquakes have been recorded on the Crescent City tide gauge, two with amplitudes greater than 0.5 m. We use the MOST model to simulate the 2006, 2007 and 1994 events and to examine the difference between damaging and non-damaging events at Crescent City. Small changes in the angle of the rupture zone results can result in a half meter difference in water heights. We also look at the contribution of fault segments along the Kuril subduction zone using the FACTS server to look at the potentially most damaging source regions for Crescent City. A similar-sized rupture as the November 15 event located further south along the Hokkaido - Honshu area of the subduction zone, is likely to produce a slightly larger amplitude signal with and even greater delay between the first wave arrivals and the largest waves.

Dengler, L.; Uslu, B.; Barberopoulou, A.

2007-12-01

156

Near-source observations and modeling of the Kuril Islands tsunamis of 15 November 2006 and 13 January 2007  

Directory of Open Access Journals (Sweden)

Full Text Available Two major earthquakes near the Central Kuril Islands (Mw=8.3 on 15 November 2006 and Mw=8.1 on 13 January 2007) generated trans-oceanic tsunamis recorded over the entire Pacific Ocean. The strongest oscillations, exceeding several meters, occurred near the source region of the Kuril Islands. Tide gauge records for both tsunamis have been thoroughly examined and numerical models of the events have been constructed. The models of the 2006 and 2007 events include two important advancements in the simulation of seismically generated tsunamis: (a) the use of the finite failure source models by Ji (2006, 2007) which provide more detailed information than conventional models on spatial displacements in the source areas and which avoid uncertainties in source extent; and (b) the use of the three-dimensional Laplace equation to reconstruct the initial tsunami sea surface elevation (avoiding the usual shallow-water approximation). The close agreement of our simulated results with the observed tsunami waveforms at the open-ocean DART stations support the validity of this approach. Observational and model findings reveal that energy fluxes of the tsunami waves from the source areas were mainly directed southeastward toward the Hawaiian Islands, with relatively little energy propagation into the Sea of Okhotsk. A marked feature of both tsunamis was their high-frequency content, with typical wave periods ranging from 2–3 to 15–20 min. Despite certain similarities, the two tsunamis were essentially different and had opposite polarity: the leading wave of the November 2006 trans-oceanic tsunami was positive, while that for the January 2007 trans-oceanic tsunami was negative. Numerical modeling of both tsunamis indicates that, due to differences in their seismic source properties, the 2006 tsunami was more wide-spread but less focused than the 2007 tsunami.

A. B. Rabinovich; L. I. Lobkovsky; I. V. Fine; R. E. Thomson; T. N. Ivelskaya; E. A. Kulikov

2008-01-01

157

Tsunamis and Earthquakes (Local Tsunamis in the Pacific Northwest)  

Science.gov (United States)

On the Pacific Northwest an oceanic tectonic plate (Juan de Fuca) is being pulled and driven (subducted) beneath the North American continental plate. Earthquakes generated along that fault may produce local tsunamis. Local tsunamis are those generated by earthquakes near the coast. This site provides links to external webpages describing the physics behind a tsunami. Resources featured in the links include glossary of terms and photo galleries.

158

Revision of the Portuguese catalog of tsunamis  

Directory of Open Access Journals (Sweden)

Full Text Available Catastrophic tsunamis are described in historical sources for all regions around the Gulf of Cadiz, at least since 60 BC. Most of the known events are associated with moderate to large earthquakes and among them the better studied is 1 November 1755. We present here a review of the events which effects, on the coasts of the Portuguese mainland and Madeira Island, are well described in historical documents or have been measured by tide gauges since the installation of these instruments. For a few we include new relevant information for the assessment of the tsunami generation or effects, and we discard events that are included in existing compilations but are not supported by quality historical sources or instrumental records. We quote the most relevant quantitative descriptions of tsunami effects on the Portuguese coast, including in all pertinent cases a critical review of the coeval sources, to establish a homogenous event list. When available, instrumental information is presented. We complement all this information with a summary of the conclusions established by paleo-tsunami research.

M. A. Baptista; J. M. Miranda

2009-01-01

159

Field survey of the March 28, 2005 Nias-Simeulue earthquake and Tsunami  

Science.gov (United States)

On the evening of March 28, 2005 at 11:09 p.m. local time (16:09 UTC), a large earthquake occurred offshore of West Sumatra, Indonesia. With a moment magnitude (Mw) of 8.6, the event caused substantial shaking damage and land level changes between Simeulue Island in the north and the Batu Islands in the south. The earthquake also generated a tsunami, which was observed throughout the source region as well as on distant tide gauges. While the tsunami was not as extreme as the tsunami of December 26th, 2004, it did cause significant flooding and damage at some locations. The spatial and temporal proximity of the two events led to a unique set of observational data from the earthquake and tsunami as well as insights relevant to tsunami hazard planning and education efforts. ?? 2010 Springer Basel AG.

Borrero, J. C.; McAdoo, B.; Jaffe, B.; Dengler, L.; Gelfenbaum, G.; Higman, B.; Hidayat, R.; Moore, A.; Kongko, W.; Lukijanto; Peters, R.; Prasetya, G.; Titov, V.; Yulianto, E.

2011-01-01

160

A review of tsunami simulation activities for NPPs safety  

International Nuclear Information System (INIS)

The tsunami generated on December 26, 2004 due to Sumatra earthquake of magnitude 9.3 resulted in inundation at the various coastal sites of India. The site selection and design of Indian nuclear power plants demand the evaluation of run up and the structural barriers for the coastal plants: Besides it is also desirable to evaluate the early warning system for tsunamigenic earthquakes. The tsunamis originate from submarine faults, underwater volcanic activities, sub-aerial landslides impinging on the sea and submarine landslides. In case of a submarine earthquake-induced tsunami the wave is generated in the fluid domain due to displacement of the seabed. There are three phases of tsunami: generation, propagation, and run-up. Reactor Safety Division (RSD) of Bhabha Atomic Research Centre (BARC), Trombay has initiated computational simulation for all the three phases of tsunami source generation, its propagation and finally run up evaluation for the protection of public life, property and various industrial infrastructures located on the coastal regions of India. These studies could be effectively utilized for design and implementation of early warning system for coastal region of the country apart from catering to the needs of Indian nuclear installations. This paper presents some results of tsunami waves based on finite difference numerical approaches with shallow water wave theory. The present paper evaluate the results of various simulation i.e. Single fault Sumatra model, four and five fault Sumatra Model, Nias insignificant tsunami and also some parametric studies results for tsunami waring system scenario generation. A study is carried for the tsunami due to Sumatra earthquake in 2004 with TUNAMI-N2 software. Bathymetry data available from the National Geophysical Data Center was used for this study. The single fault and detailed four and five fault data were used to calculate sea surface deformations which were subsequently used as initial conditions for Sumatra 2004 tsunami propagation simulation. The paper also presents a hypothetical study by assuming the earthquake rupture on northern fault only as compared to complete (northern and southern) rupture segment and the resulting tsunami propagation scenario. All of the studies provide the results in terms of wave heights and compare them with the reported simulation, satellite observation and field observed reported data. The paper includes the parametric studies on the possible fault line for Sumatra fault line for support for early tsunami warning. The various other events i.e Java, Nias, Makaran, Andaman etc are also discussed in the paper. (author)

2011-01-01

 
 
 
 
161

Numerical analysis of the mobility of the Palos Verdes debris avalanche, California, and its implication for the generation of tsunamis  

Science.gov (United States)

Analysis of morphology, failure and post-failure stages of the Palos Verdes debris avalanche reveals that it may have triggered a significant tsunami wave. Our analysis of the failure itself indicates that the slope is stable under aseismic conditions but that a major earthquake (with a magnitude around 7) could have triggered the slide. A post-failure analysis, considering the debris avalanche as a bi-linear flow, shows that peak velocities of up to 45 m/s could have been reached and that the initial movement involved a mass of rock less than 10 km wide, 1 km long and about 50-80 m thick. Initial wave height estimates vary from 10 to 50 m. Tsunami waves propagating to the local shoreline would be significantly smaller. Such a range demonstrates our lack of proper knowledge of the transition from failure to post-failure behavior related to mass movements. Further investigations and analyses of terrestrial and submarine evidence are required for a proper hazard assessment related to tsunami generation in the Los Angeles area. ?? 2003 Elsevier B.V. All rights reserved.

Locat, J.; Lee, H. J.; Locat, P.; Imran, J.

2004-01-01

162

Tsunami hazard assessment for the Azores archipelago: a historical review  

Science.gov (United States)

The Azores islands due to its complex geographical and geodynamic setting are exposed to tsunamigenic events associated to different triggering mechanisms, local or distant. Since the settlement of the Azores, in the fifteenth century, there are several documents that relate coastal areas flooding episodes with unusually high waves which caused death and destruction. This work had as main objective the characterization of the different events that can be associated with tsunamigenic phenomena, registered in the archipelago. With this aim, it was collected diverse documentation like chronics, manuscripts, newspaper articles and magazines, scientific publications, and international databases available online. From all the studied tsunami events it was identified the occurrence of some teletsunamis, among which the most relevant was triggered by the 1st November 1755 Lisbon earthquake, with an epicenter SW of Portugal, which killed 6 people in Terceira island. It is also noted the teletsunami generated by the 1761 earthquake, located in the same region as the latest, and the one generated in 1929 by an earthquake-triggered submarine landslide in the Grand Banks of Newfoundland. From the local events, originated in the Azores, the most significant were the tsunamis triggered by 1757 and 1980 earthquakes, both associated with the Terceira Rift dynamics. In the first case the waves may also be due to earthquake-triggered. With respect to tsunamis triggered by sea cliffs landslides it is important to mention the 1847 Quebrada Nova and the 1980 Rocha Alta events, both located in the Flores Island. The 1847 event is the deadliest tsunami recorded in Azores since 10 people died in Flores and Corvo islands in result of the propagated wave. The developed studies improve knowledge of the tsunami sources that affected the Azores during its history, also revealing the importance of awareness about this natural phenomenon. The obtained results showed that the tsunami hazard in the Azores is mostly driven from the events triggered by distant earthquakes and local earthquakes and landslides. In this context, were identified 12 tsunami events. In another context, it were identified 6 events associated with coastal areas flooding due to floods and/or extreme weather phenomena, hypothetically identified as meteotsunamis. It should be stressed that, despite the differences associated with their triggering mechanisms, both the tsunamis generated by geological factors and those related to atmospheric phenomena may have similar impact. Although the absence of reports identifying tsunamis associated with volcanic activity, the eruptive history of the Azores active volcanoes shows high magnitude eruptions with considerable tsunamigenic potential.

Cabral, Nuno; Ferreira, Teresa; Queiroz, Maria Gabriela

2010-05-01

163

Tsunami Society  

Science.gov (United States)

This Web site assists the international Tsunami Society in its mission to distribute "knowledge about tsunamis to scientists, officials, and the public." In the first section of the site, scientists can download articles from the 2002 and 2003 issues of the journal Science of Tsunami Hazards. Visitors can also view footage from tsunamis around the world. The second section of the site discusses the details of the society including its origin, award recipients, and symposiums.

164

NOAA Tsunami  

Science.gov (United States)

Web site developed by the National Oceanic and Atmospheric Administration (NOAA) on issues surrounding tsunamis. It provides an extensive selection of links to information on how tsunamis are created, hazards associated with them, and how individuals and communities can prepare and respond to a tsunami. There is also information about the NOAA's role in tsunami warnings and preparedness, including locations of warning centers in the Pacific Ocean Basin, observations and data, forecasts, and hazard-assessment research and modeling.

165

Tsunami Warning  

Science.gov (United States)

This learning resource is a news report by the Science reports on Tsunami warning.The devastating tsunamis that struck South Asia highlighted the need for an early tsunami warning system for the Indian Ocean like the one in place in the Pacific Ocean. Correspondent Betty Ann Bowser of the NewsHour's Science Unit reports on the science of tsunami warnings.This report includes a lesson plan and additional coverage

The Science Reports (;)

2005-01-11

166

NOAA/WEST COAST AND ALASKA TSUNAMI WARNING CENTER ATLANTIC OCEAN RESPONSE CRITERIA  

Directory of Open Access Journals (Sweden)

Full Text Available West Coast/Alaska Tsunami Warning Center (WCATWC) response criteria for earthquakes occurring in the Atlantic and Caribbean basins are presented. Initial warning center decisions are based on an earthquake’s location, magnitude, depth, distance from coastal locations, and pre- computed threat estimates based on tsunami models computed from similar events. The new criteria will help limit the geographical extent of warnings and advisories to threatened regions, and complement the new operational tsunami product suite. Criteria are set for tsunamis generated by earthquakes, which are by far the main cause of tsunami generation (either directly through sea floor displacement or indirectly by triggering of sub-sea landslides).The new criteria require development of a threat data base which sets warning or advisory zones based on location, magnitude, and pre-computed tsunami models. The models determine coastal tsunami amplitudes based on likely tsunami source parameters for a given event. Based on the computed amplitude, warning and advisory zones are pre-set.

Paul Whitmore; Uri ten Brink; Michael Caropolo; Victor Huerfano-Moreno; William Knight; William Sammler; Al Sandrik

2009-01-01

167

Event generation with SHERPA 1.1  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper the current release of the Monte Carlo event generator Sherpa, version 1.1, is presented. Sherpa is a general-purpose tool for the simulation of particle collisions at high-energy colliders. It contains a very flexible tree-level matrix-element generator for the calculation of hard sca...

Gleisberg, T; Höche, S; Krauss, F; Schönherr, M; Schumann, S; Siegert, F; Winter, J

168

Observations, Effects and Real Time Assessment of the March 11, 2011 Tohoku-oki Tsunami in New Zealand  

Science.gov (United States)

The great Tohoku-oki earthquake of March 11, 2011 generated a devastating tsunami in the near field as well as substantial far-field effects throughout the Pacific Ocean. In New Zealand, the tsunami was widely observed and instrumentally recorded on an extensive array of coastal tidal gauges and supplemented by current velocity data from two sites. While the tsunami's first arrival was on the morning of March 12 in New Zealand, the strongest effects occurred throughout that afternoon and into the following day. Tsunami effects consisted primarily of rapid changes in water level and associated strong currents that affected numerous bays, harbors, tidal inlets and marine facilities, particularly on the northern and eastern shores of the North Island. The tsunami caused moderate damage and significant overland flooding at one location. The tsunami signal was clearly evident on tide gauge recordings for well over 2 days, clearly illustrating the extended duration of far field tsunami hazards. Real time analysis and modelling of the tsunami through the night of March 11, as the tsunami crossed the Pacific, was used as a basis for escalating the predicted threat level for the northern region of New Zealand. A comparison to recorded data following the tsunami shows that these real time prediction models were accurate despite the coarse near-shore bathymetry used in the assessment, suggesting the efficacy of such techniques for future events from far-field sources.

Borrero, Jose C.; Bell, Rob; Csato, Claudia; DeLange, Willem; Goring, Derek; Dougal Greer, S.; Pickett, Vernon; Power, William

2013-06-01

169

Tsunamis in Cuba?  

International Nuclear Information System (INIS)

Cuba as neo tectonics structure in the southern of the North American plate had three tsunamis. One of them [local] occurred in the Central-Northern region [1931.10.01, Nortecubana fault], the other was a tele tsunami [1755.11.01, in the SW of the Iberian Peninsula] that hit the Bay of Santiago de Cuba, and the third took place at 1867.11.18, by the regional source of Virgin Islands, which produced waves in the Eastern Cuban region. This tsunami originated to the NE of Puerto Rico in 1918.10.11, with another earthquake of equal magnitude and at similar coordinates, produced a tsunami that did not affect Cuba. Information on the influence of regional tsunami in 1946.08.08 of the NE of the Dominican Republic [Matanzas] in Northwestern Cuba [beaches Guanabo-Baracoa] is contrary to expectations with the waves propagation. The local event of 1939.08.15 attributed to Central- Northern Cuba [Cayo Frances with M = 8.1] does not correspond at all with the maximum magnitude of earthquakes in this region and the potential of the Nortecubana fault. Tsunamis attributed to events such as 1766.06.11 and 1932.02.03 in the Santiago de Cuba Bay are not reflected in the original documents from experts and eyewitnesses. Tsunamis from Jamaica have not affected the coasts of Cuba, despite its proximity. There is no influence in Cuba of tsunamigenic sources of the southern and western parts of the Caribbean, or the Gulf of Mexico. Set out the doubts as to the influence of tsunamis from Haiti and Dominican Republic at Guantanamo Bay which is closer to and on the same latitude, and spatial orientation than the counterpart of Santiago de Cuba, that had impact. The number of fatalities by authors in the Caribbean is different and contradictory. (Author) 76 refs.

2011-01-01

170

Occurrence of cardiovascular events after the 2011 great East Japan earthquake and tsunami disaster.  

UK PubMed Central (United Kingdom)

There are conflicting reports regarding the occurrence of cardiovascular events after a major earthquake. To understand the impact of the Great East Japan Earthquake on cardiovascular events, we retrospectively examined the clinical records prepared by emergency room physicians between 2009 and 2011 (n = 66,244), and compared the occurrence of these events between 2011 and 2009, and 2011 and 2010. There was a significant increase in the number of patients with cardiovascular events during the 3 week period after the earthquake in 2011 (n = 106) compared with that during the same period in 2009 (n = 72) or 2010 (n = 65) (P = 0.002). The number of patients with acute coronary syndrome or congestive heart failure in March 2011 was significantly increased compared with 2009 or 2010, however, there were no significant increases in 2011 in other cardiovascular events including stroke, aortic dissection, pulmonary thromboembolism, or out-of-hospital cardiac arrest compared with 2009 or 2010. These findings suggest that the incidence of cardiovascular events may have been heterogeneous after the disaster.

Nozaki E; Nakamura A; Abe A; Kagaya Y; Kohzu K; Sato K; Nakajima S; Fukui S; Endo H; Takahashi T; Seki H; Tamaki K; Mochizuki I

2013-01-01

171

Note on the 1964 Alaska Tsunami Generation by Horizontal Displacements of Ocean Bottom. Numerical Modeling of the Runup in Chenega Cove, Alaska  

Science.gov (United States)

A numerical model of the wave dynamics in Chenega Cove, Alaska during the historic M w 9.2 megathrust earthquake is presented. During the earthquake, locally generated waves of unknown origin were identified at the village of Chenega, located in the western part of Prince William Sound. The waves appeared shortly after the shaking began and swept away most of the buildings while the shaking continued. We model the tectonic tsunami in Chenega Cove assuming different tsunami generation processes. Modeled results are compared with eyewitness reports and an observed runup. Results of the numerical experiments let us claim the importance of including both vertical and horizontal displacement into the 1964 tsunami generation process. We also present an explanation for the fact that arrivals of later waves in Chenega were unnoticed.

Nicolsky, D. J.; Suleimani, E. N.; Hansen, R. A.

2013-09-01

172

Identification of Forerunners and Transmission of Energy to Tsunami Waves Generated by Instanteneous Ground Motion on a Non-Uniformly Sloping Beach  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The problem of generation and propagation of tsunami waves is mainly focused on plane beach, there are very few analytical works where wave generation is considered on non-uniformly sloping beach and as a result those works might have failed to ...

Arghya Bandyopadhyay

173

MEtop - a top FCNC event generator  

CERN Document Server

We present a new Monte Carlo generator for Direct top and Single top production via flavour-changing neutral currents (FCNC). This new tool calculates the cross section and generates events with Next-to-Leading order precision for the Direct top process and Leading-Order precision for all other FCNC single top processes. A set of independent dimension six FCNC operators has been implemented - including four-fermion operators - where at least one top-quark is present in the interaction.

Coimbra, Rita; Santos, Rui; Won, Miguel

2013-01-01

174

TSUNAMI CATALOG AND VULNERABILITY OF MARTINIQUE (LESSER ANTILLES, FRANCE)  

Directory of Open Access Journals (Sweden)

Full Text Available In addition to meteorological hazards (hurricanes, heavy rainfalls, long-period swells, etc.), the Caribbean Islands are vulnerable to geological hazards such as earthquakes, landslides and volcanic eruptions caused by the complex tectonic activity and interactions in the region. Such events have generated frequently local or regional tsunamis, which often have affected the island of Martinique in the French West Indies. Over the past centuries, the island has been struck by destructive waves associated with local or regional events - such as those associated with the eruption of the Saint-Vincent volcano in 1902 and by tsunamis of distant origin as that generated by the 1755 Lisbon earthquake.The present study includes a classification of tsunamis that have affected Martinique since its discovery in 1502. It is based on international tsunami catalogs, historical accounts, and previous scientific studies and identifies tsunamigenic areas that could potentially generate destructive waves that could impact specific coastal areas of Martinique Island. The potential threat from tsunamis has been greatly increasing because of rapid urban expansion of coastal areas and development of tourism on the island.

Accary, F.; Roger, J.

2010-01-01

175

Tsunami Surge  

Science.gov (United States)

Tsunami Surge is a project for students in grades 6-12 that uses real-time data sources from the internet to help students answer these questions. They will be challenged to think critically and creatively in their efforts to understand, predict, and guard against this powerful force of nature. Students will learn to describe what a tsunami is and what causes it, explain how tsunamis are different from regular waves in the ocean, determine where tsunamis are most likely to originate, create a plan for a tsunami warning system, and explain how to prepare and protect an area that could be hit by a tsunami. There are many activities and helpful tools for the teachers, like a reference guide and teacher guide.

2006-01-01

176

Use of a Pre-Computed Data Base of Tsunami Simulations for Rapid Estimation of Tsunami Amplitude: Application to the Effective Tsunami Warning of the Great Tsunami of 11 March 2011 IN French Polynesia  

Science.gov (United States)

We developed a method giving a rapid and accurate estimation of the tsunami amplitude based on a pre-computed database of numerical simulations; this methodology has been applied in real-time in an operational context during the March 2011 Honshu tsunami alert in French Polynesia. For this purpose we constructed a pre-computed database of numerical simulations of tsunamis for 260 scenarios, involving 20 source regions distributed in the main dangerous circum Pacific subduction zones. For each region, we consider 3 types of generic sources defined by their seismic moment and their sources dimensions: MEGA (corresponding to a scalar moment Mo of 1023 N.m), BIG (Mo = 1022 N.m) and AVERAGE (Mo = 1021 N.m). All the pre-computed scenarios give the maximum height of the sea surface in deep ocean with a time step of 1 hour. The database also includes all the synthetic waveforms (14 820) at 57 virtual receivers, including all existing DART buoys, thus allowing comparisons between calculated and observed data. The latter can help to detect abnormal earthquakes (e.g., "tsunami earthquakes", generating a larger tsunami than expected, or conversely, a "snappy" earthquake generating a deficient tsunami. The distribution of tsunami heights along a coastline is then calculated from the deep ocean sea surface using Green's law and stopping the computation at a depth of 5 m. A modified formulation of Green's law has been introduced to take into account large amplification effects of some bays in the Marquesas Islands. This method gives good results in agreement with the measures and observations made during the post tsunami field surveys of the events of Chile February 2010 and Japan March 2011

Reymond, D.; Hebert, H.; Okal, E.

2011-12-01

177

Tsunami: Un problema matemáticamente interesante/ Tsunami: An interesting mathematical problema  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Se presentan algunos aspectos fundamentales respecto a la matemática y la herramienta computacional que apoyan la compleja descripción del proceso físico tsunami desde dos enfoques específicos. En particular, se aborda analíticamente un modelo hidroelástico simple para el problema de generación de ondas tsunami, el cual permite obtener resultados en el área de ruptura. Por otra parte, el proceso de propagación de las ondas tsunami en el océano y el impacto a lo (more) largo de la línea costera se analiza numéricamente utilizando el enfoque hidrodinámico, presentando en particular una aplicación directa sobre la predicción de tsunamis en México producidos por sismos potenciales en la trinchera Mesoamericana mediante el diseño de un “Módulo Sintetizador de Tsunamis” para simular tsunamis originados por sismos ocurridos en la zona de subducción de la costa occidental de México. Abstract in english We present some key aspects regarding the mathematics and the computational tool that support the complex description of the physical process tsunami from two specific approaches. In particular, it addresses analytically a simple hydroelastic model for the problem of tsunami wave generation, which provides results in the rupture area. Moreover, the propagation of tsunami waves in the ocean and the impact along the coastline is analyzed numerically using the hydrodynamic a (more) pproach, presenting in particular a direct application to the prediction of tsunamis in Mexico caused by potential earthquakes in the Mesoamerican trench through the design of a “Tsunami Toolbox” to simulate tsunamis caused by earthquakes in the subduction zone on the western coast of Mexico.

González González, Rodrigo; Ortiz Figueroa, Modesto; Montoya Rodríguez, José Miguel

2012-01-01

178

Numerical modeling of the 1964 Alaska tsunami in western Passage Canal and Whittier, Alaska  

Directory of Open Access Journals (Sweden)

Full Text Available A numerical model of the wave dynamics in Passage Canal, Alaska during the Mw 9.2 megathrust earthquake is presented. During the earthquake, several types of waves were identified at the city of Whittier, located at the head of Passage Canal. The first wave is thought to have been a seiche, while the other two waves were probably triggered by submarine landslides. We model the seiche wave, landslide-generated tsunami, and tectonic tsunami in Passage Canal and compute inundation by each type of wave during the 1964 event. Modeled results are compared with eyewitness reports and an observed inundation line. Results of the numerical experiments let us identify where the submarine landslides might have occurred during the 1964 event. We identify regions at the head and along the northern shore of Passage Canal, where landslides triggered a wave that caused most of the damage in Whittier. An explanation of the fact that the 1964 tectonic tsunami in Whittier was unnoticed is presented as well. The simulated inundation by the seiche, landslide-generated tsunami, and tectonic tsunami can help to mitigate tsunami hazards and prepare Whittier for a potential tsunami.

D. J. Nicolsky; E. N. Suleimani; R. A. Hansen

2010-01-01

179

Tsunami deposits in the Balearic Islands (western Mediterranean) and implications for hazard assessment.  

Science.gov (United States)

Significant earthquakes occur along the north Algerian and Carboneras faults (e.g. Djijelli 1865, Zemmouri 2003) and they may generate tsunamis in the western Mediterranean Basin and Alboran Sea, where tsunami hazard are poorly documented. The coast of southern Spain and Balearic Islands are densely populated, with touristic areas and important harbors. The 2003 event generated a small tsunami in the Balearic Islands (ships were moved by oscillations during more than 2 hours in some harbors). Reicherter et al. (2009) found evidences of two past tsunamis in lagoon of the Cabo de Gata (near Almeria), which they ascribed to the 1522 earthquake and an earlier event (< 850 BP). Field surveys along the coasts of Mallorca and Menorca islands revealed few evidences of past tsunamis. Thin sandy layers with marine bioclasts, possibly deposited by tsunamis, were found in three areas at altitudes always lower than 2m. Boulder clusters were found along the southern coast of Mallorca, but they could have been deposited by storms as well. These investigations are realized in the framework of the MAREMOTI project, funded by the French ANR and leaded by the CEA - DASE. Reicherter, K., Becker-Heidmann, P., 2009. Tsunami deposits in the western Mediterranean: remains of the 1522 Almeria earthquake? Geological Society Special Publications, London, 316, 217-235.

Paris, Raphael; Wassmer, Patrick; Roger, Jean; Loevenbruck, Anne

2010-05-01

180

The Importance of the Initial Rise and Fall of the Shoreline in Preparing People to Respond to Earthquake-Generated Tsunamis  

Science.gov (United States)

One of the most conspicuous phenomena associated with tsunamis is shoreline recession preceding arrival of the tsunami wave crest. Whether the shoreline will initially rise or fall in a tsunami is an important factor to consider when anticipating the warning time available before the first wave crest arrives on shore. Where the shoreline first recedes, people may have from a few minutes to 15 minutes of time to respond. This environmental cue is not available when the shoreline initially rises as a tsunami wave crest, and there is significantly less warning time in these instances. The rise and fall of the shoreline around the Indian Ocean following the generation of the initial tsunami from the December 26, 2004 earthquake was examined by reviewing published tide-gauge data. Findings confirm the predictability of the shoreline change. Indian-Ocean-wide, coastal areas west of the trench (i.e., toward the subducted plate side of the trench, e.g., Sri Lanka) experienced an initial rise in sea level as the first tsunami wave crest arrived on shore, as occurred in Samoa in 2009. In contrast, coastlines east of the trench (i.e., toward the overthrust plate side of the trench, e.g., Thailand) initially experience a fall in sea level as the tsunami wave trough arrived on shore. An exception was on the overthrust plate proximal to the earthquake epicenter (e.g., Sumatra). There, subsidence of the coastline caused an initial rise in sea level and corresponding flooding before the shoreline receded. This recession was then followed by a greater rise in the shoreline as the first wave crest arrived onshore. Human behavior in response to environmental cues and official and informal warnings of tsunamis is complex. Little is known about the timing in which people make decisions when exposed to different sources of information. That is, why some people evacuate immediately versus delaying, or how the order of specific cues or warnings influences timely and effective response. Disaster studies have demonstrated the important role that environmental cues play in risk communications, in addition to informal and official warnings. An important step in preparing vulnerable populations for tsunamis, especially those near their source, is understanding the probability that a shoreline will first rise or fall. Risk communications should be developed that effectively translate the probabilities to useful information for vulnerable people. A realistic and accurate understanding of the order, timing and limitations of environmental cues and warnings should reduce the time people waste seeking information during the warning confirmation or information seeking process.

Gregg, C. E.; Houghton, B. F.; Huffman, J.

2009-12-01

 
 
 
 
181

Numerical simulation of tsunamis generated by caldera collapse during the 7.3 ka Kikai eruption, Kyushu, Japan  

Science.gov (United States)

The relationship between tsunamis and scales of caldera collapse during a 7.3 ka eruption of the Kikai volcano were numerically investigated, and a hypothetical caldera collapse scale was established. Wave height, arrival time, and run-up height and distance were determined at some locations along the coastline around Kikai caldera, using non-linear long-wave equations and caldera collapse models using parameters showing the difference in geometry between pre- and post-collapse and the collapse duration. Whether tsunamis become large and inundations occur in coasts is estimated by the dimensionless collapse speed. Computed tsunamis were then compared with geological characteristics found in coasts. The lack of evidence of tsunami inundation at Nejime, 65 km from the caldera, suggests that any tsunamis were small; indicating that the upper limit of dimensionless caldera collapse speed was 0.01. On the other hand, on the coast of the Satsuma Peninsula, 50 km from the caldera, geological characteristics suggests that tsunamis did not inundate, or that even if tsunamis inundated the area, the traces of a tsunami have been eroded by a climactic pyroclastic flow or the tsunami itself and they have not been left. In numerical computations, when a dimensionless caldera collapse speed is more than 0.003, tsunami can inundate this area.

Maeno, F.; Imamura, F.; Taniguchi, H.

2006-08-01

182

MEtop – a top FCNC event generator  

Science.gov (United States)

In this work we present a new Monte Carlo generator for Direct top and Single top production via flavour-changing neutral currents (FCNC). This new tool calculates the cross section and generates events with Next-to-Leading order precision for the Direct top process and Leading-Order precision for all other FCNC single top processes. A set of independent dimension six FCNC operators has been implemented – including four-fermion operators – where at least one top-quark is present in the interaction.

Coimbra, Rita; Onofre, António; Santos, Rui; Won, Miguel

2013-07-01

183

The MC@NLO Event Generator  

CERN Multimedia

This is the user's manual of MC@NLO.1.0. This package is a practical implementation, based upon the HERWIG event generator, of the recently proposed MC@NLO formalism for matching the next-to-leading order calculation of a QCD process with a parton-shower Monte Carlo simulation. The processes of standard-model vector boson pair production in hadronic collisions are available.

Frixione, Stefano

2002-01-01

184

A case study of sanitary survey on community drinking water supplies after a severe (post-Tsunami) flooding event/ Caso studio di sorveglianza sanitaria in una comunità per l'approvvigionamento di acque potabili dopo un maremoto post-Tsunami  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english This report presents a case study of a comprehensive sanitary survey on ca. 160 community drinking water supplies after a severe (post-Tsunami) flooding event in Sri Lanka. Sanitary inspection and microbiological and chemical water quality analyses were performed according to specifically-designed procedures established on the World Health Organization (WHO) guidelines. Significant hazards and critical points were identified in almost all the investigated water supplies. (more) The overall results showed a significant level of microbiological and chemical risk associated with drinking water consumption within the investigated areas. The criteria and methods practised in this study are proposed as a model to assure an effective and reliable monitoring in post-emergencies involving possible deterioration of water quality and to identify health priorities related to water consumption.

Ferretti, Emanuele; Bonadonna, Lucia; Lucentini, Luca; Della Libera, Simonetta; Semproni, Maurizio; Ottaviani, Massimo

2010-01-01

185

NEAR AND FAR-FIELD EFFECTS OF TSUNAMIS GENERATED BY THE PAROXYSMAL ERUPTIONS, EXPLOSIONS, CALDERA COLLAPSES AND MASSIVE SLOPE FAILURES OF THE KRAKATAU VOLCANO IN INDONESIA ON AUGUST 26-27, 1883  

Directory of Open Access Journals (Sweden)

Full Text Available The paroxysmal phases of Krakatau's volcanic activity on August 26-27, 1883, included numerous submarine Surtsean (phreatomagmatic) eruptions, three sub air Plinian eruptions from the three main craters of Krakatau on Rakata island, followed by a fourth gigantic, sub air, Ultra-Plinian explosion. Landslides, flank failures, subsidences and a multiphase massive caldera collapse of the volcano - beginning near the Perbowetan crater on the northern portion of Rakata and followed by a collapse of the Danan crater - occurred over a period of at least 10 hours. The first of the three violent explosions occurred at 17: 07 Greenwich time (GMT) on August 26.The second and third eruptions occurred at 05:30 GMT and at 06:44 GMT on August 27. Each of these events, as well as expanding gases from the submarine phreatomagmatic eruptions, lifted the water surrounding the island into domes or truncated cones that must have been about 100 meters or more in height. The height of the resulting waves attenuated rapidly away from the source because of their short periods and wavelengths. It was the fourth colossal explosion (VEI=6) and the subsequent massive f lank failure and caldera collapse of two thirds of Rakata Island, at 10:02 a.m., on August 27 that generated the most formidable of the destructive tsunami waves. A smaller fifth explosion, which occurred at 10:52 a.m., must have generated another large water cone and sizable waves. The final collapse of a still standing wall of Krakatau - which occurred several hours later at 16:38, generated additional waves.The near field effects of the main tsunami along the Sunda Strait in Western Java and Southern Sumatra, were devastating. Within an hour after the fourth explosion/caldera collapse, waves reaching heights of up to 37 m (120 feet) destroyed 295 towns and villages and drowned a total of 36,417 people. Because of their short period and wavelength, the wave heights attenuated rapidly with distance away from the source region. It took approximately 2.5 hours for the tsunami waves to refract around Java and reach Batavia (Jakarta) where the only operating tide gauge existed. Wavesof 2.4 meters in height were recorded - but with an unusually long period of 122 minutes. The long period is attributed to modification due to resonance effects and did not reflect source characteristics. The tsunami travel time to Surabaya at the eastern part of Java was 11.9 hours. The reported wave was only 0.2 meters.The far field effects of the tsunami were noticeable around the world, but insignificant. Small sea level oscillations were recorded by tide gauges at Port Blair in the Andaman Sea, at Port Elizabeth in South Africa, and as far away as Australia, New Zealand, Japan, Hawaii, Alaska, the North-American West Coast, South America, and even as far away as the English Channel. It took 12 hours for the tsunami to reach Aden on the southern tip of the Arabian Peninsula, about 3800 nautical miles away. The wave reported at Aden, at Port Blair and at Port Elizabeth, represents the actual tsunami generated in the Sunda Strait. There were no land boundaries on the Indian Ocean side of Krakatau to prevent the tsunami energy from spreading in that direction. The tsunami travel time of a little over 300 nautical miles per hour to Aden appears reasonable. However, it is doubtful that the waves, which were reported at distant locations in the Pacific or in the Atlantic Ocean, represented the actual tsunami generated in the Sunda Strait. Very little, if any at all, of the tsunami energy could have escaped the surrounding inland seas to the east of the Sunda Strait. Most probably, the small waves that were observed in the Pacific as well as in the Atlantic were generated by the atmospheric pressure wave of the major Krakatoa explosion, and not from the actual tsunami generated in the Sunda Strait. The unusual flooding, which occurred at the Bay of Cardiff, in the U.K., was caused by atmospheric coupling of the pressure wave from the major Krakatau eruption.

George Pararas-Carayannis

2003-01-01

186

Tsunami Awareness  

Medline Plus

Full Text Available ... know the potential warning signs of an incoming tsunami: a strong earthquake that causes difficulty standing; a rapid rise or fall of the water along the coast; a load ocean roar. When you're in a ... police, The US Tsunami Warning Centers and NOAA All Hazards Radio. If ...

187

CAPTURING THE NEXT GENERATION OF CULTURAL MEMORIES – THE PROCESS OF VIDEO INTERVIEWING TSUNAMI SURVIVORS  

Directory of Open Access Journals (Sweden)

Full Text Available Traditional story telling is rare in many cultures these days and yet stories are an effective way of educating people of all ages. The technology of modern media is increasingly accessing all corners of the world and if used wisely can help capture and communicate messages of disaster preparedness. Planned video interviewing of tsunami survivors began around 1998 and an extensive archive has been assembled at the Pacific Tsunami Museum. Video interviewing is an effective way to collect data that are both educational and scientific. The technique however, is not simple and a protocol has been developed to achieve the best results. We explain the protocol in detail using examples where appropriate, and discuss a wide range of applications that have been developed using interview materials. Recent advances in analytical techniques mean that the previously difficult to access qualitative data of these interviews are now available for more robust scientific analysis. The database continues to grow each year. It seems likely that this publicly- available database will now be available for a whole suite of new applications that can be developed.

W. Dudley; J. Goff; C. Chagué-Goff; J. Johnston

2009-01-01

188

Tsunami wave energy  

CERN Multimedia

In the vast literature on tsunami research, few articles have been devoted to energy issues. A theoretical investigation on the energy of waves generated by bottom motion is performed here. We start with the full incompressible Euler equations in the presence of a free surface and derive both dispersive and non-dispersive shallow-water equations with an energy equation. It is shown that dispersive effects only appear at higher order in the energy budget. Then we solve the Cauchy-Poisson problem of tsunami generation for the linearized water wave equations. Exchanges between potential and kinetic energies are clearly revealed.

Dutykh, Denys

2008-01-01

189

TSUNAMI HAZARD IN NORTHERN VENEZUELA  

Directory of Open Access Journals (Sweden)

Full Text Available Based on LANDSAT ETM and Digital Elevation Model (DEM) data derived by the Shuttle Radar Topography Mission (SRTM, 2000) of the coastal areas of Northern Venezuela were investigated in order to detect traces of earlier tsunami events. Digital image processing methods used to enhance LANDSAT ETM imageries and to produce morphometric maps (such as hillshade, slope, minimum and maximum curvature maps) based on the SRTM DEM data contribute to the detection of morphologic traces that might be related to catastrophic tsunami events. These maps combined with various geodata such as seismotectonic data in a GIS environment allow the delineation of coastal regions with potential tsunami risk. The LANDSAT ETM imageries merged with digitally processed and enhanced SRTM data clearly indicate areas that might be prone by flooding in case of catastrophic tsunami events.

B. Theilen-Willige

2006-01-01

190

Scenarios for earthquake-generated tsunamis on a complex tectonic area of diffuse deformation and low velocity: The Alboran Sea, Western Mediterranean  

Science.gov (United States)

The tsunami impact on the Spanish and North African coasts of the Alboran Sea generated by several reliable seismic tsunamigenic sources in this area was modeled. The tectonic setting is complex and a study of the potential sources from geological data is basic to obtain probable source characteristics. The tectonic structures considered in this study as potentially tsunamigenic are: the Alboran Ridge associated structures, the Carboneras Fault Zone and the Yusuf Fault Zone. We characterized 12 probable tsunamigenic seismic sources in the Alboran Basin based on the results of recent oceanographical studies. The strain rate in the area is low and therefore its seismicity is moderate and cannot be used to infer characteristics of the major seismic sources. These sources have been used as input for the numerical simulation of the wave propagation, based on the solution of the nonlinear shallow water equations through a finite-difference technique. We calculated the Maximum Wave Elevations, and Tsunami Travel Times using the numerical simulations. The results are shown as maps and profiles along the Spanish and African coasts. The sources associated with the Alboran Ridge show the maximum potential to generate damaging tsunamis, with maximum wave elevations in front of the coast exceeding 1.5. m. The Carboneras and Yusuf faults are not capable of generating disastrous tsunamis on their own, although their proximity to the coast could trigger landslides and associated sea disturbances. The areas which are more exposed to the impact of tsunamis generated in the Alboran Sea are the Spanish coast between Malaga and Adra, and the African coast between Alhoceima and Melilla. ?? 2011 Elsevier B.V.

Alvarez-Gomez, J. A.; Aniel-Quiroga, I.; Gonzalez, M.; Olabarrieta, M.; Carreno, E.

2011-01-01

191

The 2010 Mw 7.8 Mentawai earthquake: Very shallow source of a rare tsunami earthquake determined from tsunami field survey and near-field GPS data  

Science.gov (United States)

The Mw 7.8 October 2010 Mentawai, Indonesia, earthquake was a "tsunami earthquake," a rare type of earthquake that generates a tsunami much larger than expected based on the seismic magnitude. It produced a locally devastating tsunami, with runup commonly in excess of 6 m. We examine this event using a combination of high-rate GPS data, from instruments located on the nearby islands, and a tsunami field survey. The GPS displacement time series are deficient in high-frequency energy, and show small coseismic displacements (16 m. Our modeling results show that the combination of the small GPS displacements and large tsunami can only be explained by high fault slip at very shallow depths, far from the islands and close to the oceanic trench. Inelastic uplift of trench sediments likely contributed to the size of the tsunami. Recent results for the 2011 Mw 9.0 Tohoko-Oki earthquake have also shown shallow fault slip, but the results from our study, which involves a smaller earthquake, provide much stronger constraints on how shallow the rupture can be, with the majority of slip for the Mentawai earthquake occurring at depths of <6 km. This result challenges the conventional wisdom that the shallow tips of subduction megathrusts are aseismic, and therefore raises important questions both about the mechanical properties of the shallow fault zone and the potential seismic and tsunami hazard of this shallow region.

Hill, Emma M.; Borrero, Jose C.; Huang, Zhenhua; Qiu, Qiang; Banerjee, Paramesh; Natawidjaja, Danny H.; Elosegui, Pedro; Fritz, Hermann M.; Suwargadi, Bambang W.; Pranantyo, Ignatius Ryan; Li, Linlin; MacPherson, Kenneth A.; Skanavis, Vassilis; Synolakis, Costas E.; Sieh, Kerry

2012-06-01

192

Tsunami Simulations for Regional Sources in the South China and Adjoining Seas  

Science.gov (United States)

The tsunami potential from sources located in the South China Sea and its adjoining basins, Sulu and Sulawesi Seas, is examined. Tsunami numerical modeling was performed using the MOST code [Titov and Synolakis, 1998] for a number of possible earthquake scenarios at the various local subduction zones. For the Sulawesi Sea, we consider the events of 1918 at the Mindanao subduction zone, and the 1996 at the Northern end of the Makassar Strait. For the Sulu Sea, we consider a scenario inspired by the 1948 Panay earthquake (because of the fractured nature of the plate system in those areas, it is not feasible to consider much larger earthquakes). Tsunami simulations of these events show that the tsunami is contained within the relevant marginal seas and does not penetrate significantly the greater South China Basin. However, tsunami hazard that could cause significant damage was found for the Eastern coast of Borneo. Farther North, we consider as worst case scenarios events reaching 10**29 dyn*cm with rupture lengths of 400 km, both off Luzon Island and, under a slightly different geometry, off the Luzon Straits separating the Philippines and Taiwan. These scenarios show very significant hazard to all coastlines bordering the South China Sea, including Indochina and Borneo. Finally, two landslide-generated tsunami scenarios are presented, inspired from the event of 14 February 1934 off the Luzon Strait, and the presumably Holocene Brunei mega-slide.

Kalligeris, N.; Okal, E. A.; Synolakis, C. E.

2009-04-01

193

Solar Tsunamis - View with a Spin  

Science.gov (United States)

Push-in to a region of the Sun to witness a solar tsunami after a flare event. The tsunami moves hot gas (bright) out of the region, revealing cooler regions (darker) below. This view rotates on the push-in to keep the region of the flare event visible (to the left in the final frame).

Bridgman, Tom; Wills-Davey, Meredith; Deforest, Craig

2005-03-08

194

Tsunami Awareness  

Medline Plus

Full Text Available ... to radiate outward in all directions. In deep waters, these waves may not even be detectable. But when the tsunami enters shallower waters, the wave speed slows and its height increases. ...

195

Tsunami Awareness  

Medline Plus

Full Text Available ... But they are most often caused by an earthquake where there's a sudden displacement of the ocean ... warning signs of an incoming tsunami: a strong earthquake that causes difficulty standing; a rapid rise or ...

196

Tsunami Awareness  

Medline Plus

Full Text Available ... it's important to keep alert for messages from local officials, such as lifeguards, police, The US Tsunami ... in a sturdy building; follow all instructions from local officials, and stay out of coastal areas until ...

197

Dynamics of tsunami waves  

CERN Multimedia

The life of a tsunami is usually divided into three phases: the generation (tsunami source), the propagation and the inundation. Each phase is complex and often described separately. A brief description of each phase is given. Model problems are identified. Their formulation is given. While some of these problems can be solved analytically, most require numerical techniques. The inundation phase is less documented than the other phases. It is shown that methods based on Smoothed Particle Hydrodynamics (SPH) are particularly well-suited for the inundation phase. Directions for future research are outlined.

Dias, F; Dias, Fr\\'ed\\'eric; Dutykh, Denys

2006-01-01

198

Proximal Tsunami Deposits Produced During the 1883 Eruption of Augustine Volcano, Alaska  

Science.gov (United States)

In 1883 a debris avalanche from Augustine Volcano flowed into Cook Inlet and generated a distal tsunami that in some localities was as much as 6-8 m high at distances of 80 km from the volcano (Beget and Kowalik, 2006). Waves generated by the landslide also propagated back to Augustine Island, and left proximal tsunami deposits on the 1883 debris avalanche and nearby parts of Augustine Island. Near the center of the 1883 debris avalanche the tsunami deposits are locally more than 2 m thick, consist mainly of marine mud with admixtures of sand, rounded pumice and shells, and are found in both laminated and massive exposures overlying hummocks on Augustine Island and adjacent Tsunami Island. Sand-dominated proximal tsunami deposits are much thinner and more discontinuous, and occur only at the margins of the 1883 landslide, and in more distal sites around Augustine Island and elsewhere around Cook Inlet. The mud-dominated and sand- dominated facies found in the proximal tsunami deposits reflect local sediment entrainment by waves travelling via different paths back to Augustine Island. The tsunami deposits record local waves that were at least 21 m high near the center of the landslide. The tsunami deposit heights systematically decrease both to the east and west away from the center of the debris avalanche, and indicate wave run-up heights of ca. 12 m at the landslide margins, and ca. 8 m at West Island. The tsunami deposits, together with evidence from erosional features and driftwood found on 1883 hummocks are used to retrodict a mareogram for the Augustine 1883 event. The 1883 maregram is similar to maregrams produced by other landslide tsunamis, and proves that the 1883 debris avalanche generated the tsunami. The 1883 mareogram also constitutes an independent test of various numerical models which purport to reconstruct the1883 tsunami. The field data from proximal tsunami deposits on Augustine Island is in agreement with numerical models that successfully simulate waves consistent with eyewitness acounts and contemporary reports of 6-8 m wave heights at English Bay (modern Nanwalek) and other sites along the lowermost Kenai Peninsula of Cook Inlet.

Keskinen, M. J.; Beget, J.

2006-12-01

199

Modelling tsunamis  

International Nuclear Information System (INIS)

We doubt the relevance of soliton theory to the modelling of tsunamis, and present a case in support of an alternative view. Although the shallow-water equations do provide, we believe, an appropriate basis for this phenomenon, an asymptotic analysis of the solution for realistic variable depths, and for suitable background flows, is essential for a complete understanding of this phenomenon. In particular we explain how a number of tsunami waves can arrive at a shoreline. (letter to the editor)

2006-04-07

200

Event generators; Generateurs d`evenements  

Energy Technology Data Exchange (ETDEWEB)

The results concerning the heavy ion collision simulations at Fermi energies by means of phenomenological models obtained in the last two years ar presented. The event generators are essentially following the phase of elaboration of analysis methods of data obtained by INDRA or NAUTILUS 4 {pi} multidetectors. To identify and correctly quantify a phenomenon or a physical quantity it is necessary to verify by simulation the feasibility and validity of the analysis and also to estimate the bias introduced by the experimental filter. Many studies have shown this, for instance: the determination of the collision reaction plan for flow studies, determination of kinematical characteristics of the quasi-projectiles, and the excitation energy measurement stored in the hot nuclei. To Eugene, the currently utilised generator, several improvements were added: introduction of space-time correlations between the different products emitted in the decay of excited nuclei by calculating the trajectories of the particles in the final phase of the reaction; taking into account in the decay cascade of the discrete levels of the lighter fragments; the possibility of the schematically description of the explosion of the nucleus by simultaneous emission of multi-fragments. Thus, by comparing the calculations with the data relative to heavy systems studied with the NAUTILUS assembly it was possible to extract the time scales in the nuclear fragmentation. The utilisation of these event generators was extended to the analysis of INDRA data concerning the determination of the vaporization threshold in the collisions Ar + Ni and also the research of the expansion effects in the collisions Xe + Sn at 50 MeV/u 9 refs.

Durand, D.; Gulminelli, F.; Lopez, O.; Vient, E. [Lab. de Physique Corpusculaire, Caen Univ., 14 (France)

1998-04-01

 
 
 
 
201

A Tsunami PSA for Nuclear Power Plants in Korea  

Energy Technology Data Exchange (ETDEWEB)

For the evaluation of safety of NPP caused by Tsunami event, probabilistic safety assessment (PSA) method was applied in this study. At first, an empirical tsunami hazard analysis performed for an evaluation of tsunami return period. A procedure for tsunami fragility methodology was established, and target equipment and structures for investigation of Tsunami Hazard assessment were selected. A several fragility calculations were performed for equipment in Nuclear Power Plant and finally accident scenario of tsunami event in NPP was presented. Finally, a system analysis performed in the case of tsunami event for an evaluation of a CDF of Ulchin 56 NPP site. For the evaluation of safety of NPP caused by Tsunami event, probabilistic safety assessment (PSA) method was applied. A procedure for tsunami fragility methodology was established, and target equipment and structures for investigation of Tsunami Hazard assessment were selected. A several fragility calculations were performed for equipment in Nuclear Power Plant and finally accident scenario of tsunami event in NPP was presented. As a result, in the case of tsunami event, functional failure is mostly governed total failure probability of facilities in NPP site

Kim, Min Kyu; Choi, In Kil; Park, Jin Hee; Seo, Kyung Suk; Seo, Jeong Moon; Yang, Joon Eon

2010-06-15

202

SOME OPPORTUNITITES OF THE LANDSLIDE TSUNAMI HYPOTHESIS  

Directory of Open Access Journals (Sweden)

Full Text Available Tsunami sources are intimately linked to geological events. Earthquakes and landslides are shown to be part of a continuum of complicated geological phenomena. Advances in landslide tsunami research will remain coupled with marine geology research. The landslide tsunami hypothesis is shown to have originated in the scientific literature in the early 1900s. Tsunami science has been slow to embrace the hypothesis in part because of the tremendous uncertainity that it introduces into tsunami gneration. The 1998 Papua New Guyinea event sparked much controbersy regarding the landslide tsunami hypothesis despite a preponderance of the evidence in favor of one simple and consistent explanation of the tsunami source. Part of the difficulty was the unanticipated distinction between slide and slump tsunami sources. Significant controversies still exist over other aspects of the Papua New Guinea event. The landslide hypothesis will become widely acceepted once direct measurements of underwater landslide events are made. These measurements will likely be integrated into a local tsunami warning system.

Phillip Watts

2001-01-01

203

A tsunami PSA methodology and application for NPP site in Korea  

International Nuclear Information System (INIS)

Highlights: ? A methodology of tsunami PSA was developed in this study. ? Tsunami return period was evaluated by empirical method using historical tsunami record and tidal gauge record. ? Procedure of tsunami fragility analysis was established and target equipments and structures for investigation of tsunami fragility assessment were selected. ? A sample fragility calculation was performed for the equipment in Nuclear Power Plant. ? Accident sequence of tsunami event is developed by according to the tsunami run-up and draw down, and tsunami induced core damage frequency (CDF) is determined. - Abstract: A methodology of tsunami PSA was developed in this study. A tsunami PSA consists of tsunami hazard analysis, tsunami fragility analysis and system analysis. In the case of tsunami hazard analysis, evaluation of tsunami return period is a major task. For the evaluation of tsunami return period, numerical analysis and empirical method can be applied. In this study, tsunami return period was evaluated by empirical method using historical tsunami record and tidal gauge record. For the performing a tsunami fragility analysis, procedure of tsunami fragility analysis was established and target equipments and structures for investigation of tsunami fragility assessment were selected. A sample fragility calculation was performed for the equipment in Nuclear Power Plant. In the case of system analysis, accident sequence of tsunami event is developed by according to the tsunami run-up and draw down, and tsunami induced core damage frequency (CDF) is determined. For the application to the real Nuclear Power Plant, the Ulchin 56 NPP which located in east coast of Korean peninsula was selected. Through this study, whole tsunami PSA working procedure was established and example calculation was performed for one of real Nuclear Power Plant in Korea. But for more accurate tsunami PSA result, there are many researches needed for evaluation of hydrodynamic force, effect of debris, structural failure probability of break water structure and intake structure, functional failure criteria for offsite power.

2012-01-01

204

Rapid tsunami models and earthquake source parameters: Far-field and local applications  

Science.gov (United States)

Rapid tsunami models have recently been developed to forecast far-field tsunami amplitudes from initial earthquake information (magnitude and hypocenter). Earthquake source parameters that directly affect tsunami generation as used in rapid tsunami models are examined, with particular attention to local versus far-field application of those models. First, validity of the assumption that the focal mechanism and type of faulting for tsunamigenic earthquakes is similar in a given region can be evaluated by measuring the seismic consistency of past events. Second, the assumption that slip occurs uniformly over an area of rupture will most often underestimate the amplitude and leading-wave steepness of the local tsunami. Third, sometimes large magnitude earthquakes will exhibit a high degree of spatial heterogeneity such that tsunami sources will be composed of distinct sub-events that can cause constructive and destructive interference in the wavefield away from the source. Using a stochastic source model, it is demonstrated that local tsunami amplitudes vary by as much as a factor of two or more, depending on the local bathymetry. If other earthquake source parameters such as focal depth or shear modulus are varied in addition to the slip distribution patterns, even greater uncertainty in local tsunami amplitude is expected for earthquakes of similar magnitude. Because of the short amount of time available to issue local warnings and because of the high degree of uncertainty associated with local, model-based forecasts as suggested by this study, direct wave height observations and a strong public education and preparedness program are critical for those regions near suspected tsunami sources.

Geist, E. L.

2005-01-01

205

Potential Significant Tsunami Hazard in the Puysegur Subduction Zone, South of New Zealand  

Science.gov (United States)

Subduction zone seismogenesis and related tsunami potential have recently become a significant focus; yet none of the recent global studies have considered the Puysegur subduction zone, south of New Zealand, and its hazards. While several local studies have identified the southern and southwestern (Fiordland) margins as potential tsunami hazards, those models fail to take into account the oblique nature of subduction and the impact of that obliquity on earthquake slip and tsunami wave generation. We have undertaken a comprehensive study of the Puysegur subduction zone and its earthquake and tsunami hazards by analyzing the historical seismicity over the entire plate boundary region south of New Zealand and using that data to constrain the earthquake potential for the Puysegur trench. We have identified both seismicity clearly associated with the interplate megathrust, and using these events, determined the seismic moment deficit of the subduction plate boundary over the past ~100 years. These calculations imply unreleased moment equivalent to a magnitude Mw 8.4 earthquake, and thus suggest that this subduction zone has the potential to break in a great, tsunamigenic event. We model the tsunami hazard using this moment deficit and the location of the 1979 plate interface event, and find that a tsunami caused by a great earthquake on the Puysegur subduction zone poses a significant threat to the southern and western coasts of the South Island of New Zealand, the coasts of Tasmania, and also to the southeastern coast of Australia, nearly 2000 km distant.

Hayes, G. P.; Furlong, K. P.

2009-04-01

206

Assessment of tsunami hazard for the American Pacific coast from southern Mexico to northern Peru  

Science.gov (United States)

Central America has been struck by at least 49 tsunamis between 1539 and 1996. As many as 37 of these events occurred at the Pacific Coast, and 31 were generated by earthquakes. Some of the events have been destructive, but despite this, tsunamis are an underrated hazard in Central America: people are not aware that they are at risk and even recent tsunami events have been forgotten. Recent studies, following the destructive tsunami occurred in Nicaragua in 1992, have revealed that Central America is a moderately tsunamigenic zone that is mainly affected by tsunamis triggered by earthquakes, especially at the Pacific coast where the Middle American Trench runs parallel to the coast. In this study, a statistical first and then a deterministic analysis for the Pacific coast of Central America has been carried out. The statistical approach aims to estimate the Gutenberg-Richter coefficients of the main seismic tsunamigenic regions of the area in order to assess the annual rate of occurrence of tsunamigenic earthquakes and their corresponding return period. A deterministic approach is then used to compute the tsunami run-up distribution along the coast corresponding to a given annual rate of occurrence of tsunamigenic earthquakes.

Brizuela, B.; Armigliato, A.; Tinti, S.

2013-06-01

207

Seismological evidence for a tsunami earthquake recorded four centuries ago on historical documents  

Science.gov (United States)

Historical documents reveal that a series of large earthquakes occurred in the past 1400 yr along the Nankai Trough at an interval of 100-150 yr. These documents, combined with recent seismological data, show that the five most recent large earthquakes are megathrust events that occurred on the upper interface of the Philippine Sea Plate. However, the 1605 Keicho earthquake (Mt = 8.2) differs from these five events: extensive tsunami damage occurred along the western coast of Japan, despite a relative lack of damage due to strong ground motions. Based on these data, the earthquake is thought to be a `tsunami earthquake', which generates a disproportionally large tsunami compared to its seismic waves. In this study, we carefully examined a diary in which the writer described earthquakes felt in Kyoto over 41 yr. Detailed analysis shows that it is extremely unlikely that the writer did not record the event in the diary. Assuming that this event occurred on the shallower plate interface near the trench axis, a tsunami simulation was performed based on the data recorded in historical documents. If the 1605 earthquake is a `tsunami earthquake', this earthquake cannot be considered an ordinary thrusting event on the seismogenic zone of the plate interface that occurs at an interval of 100-150 yr along the Nankai Trough. If we exclude this event from such a group, the interseismic interval increases to approximately 200-400 yr, which implies that large earthquakes occur with a wide range of interval.

Ando, Masataka; Nakamura, Mamoru

2013-08-01

208

Modeling tsunami propagation in the Iberia–Africa plate boundary: Historical events, regional exposure and the case-study of the former Gulf of Tartessos  

Science.gov (United States)

A numerical model to simulate tsunami propagation in south of Iberia waters has been developed. It is based on the 2D non-linear hydrodynamic equations and allows calculating tsunami run-ups. The model has been validated through the simulation of historical tsunamis. Then it is applied to a risk assessment study to evaluate tsunami flooding along the Spanish and Moroccan coasts. A spectral analysis of tsunami waves has also been carried out. Finally, the model has been applied to simulate tsunami propagation in the former Gulf of Tartessos, where the city of the same name could have been located. The objective consists of evaluating if a large tsunami could have destroyed it, as some historians suggest.

Periáñez, R.; Abril, J. M.

2013-02-01

209

Differentiating earthquake tsunamis from other sources; how do we tell the difference?  

Science.gov (United States)

When a great earthquake generates a large magnitude tsunami, the focus is on the relationship between the two, usually addressed through analysis of earthquake, tide and geodetic data, often in various combinations. These methods, however, have limitations in resolving the up-dip extent of rupture; onshore geodetic inversions have limited sensitivity to slip offshore, seismic inversions have instabilities in moment estimation where subfault segments are shallow, and tsunami inversions average over the large areas of ocean bottom uplift. Seismic wave estimates depend on the velocity structure, which affects both seismic moment estimation and inferred slip. Validation of tsunami generating mechanism is mainly from tide gauges, although there are problems and assumptions made in their use. Models may be circular, with inversion of the data used to identify earthquake rupture that is then modeled as the tsunami source. Different slip distributions may be modelled and the results compared with recorded surface elevations offshore and inundation data, then adjusted to provide new scenarios in order to improve the agreement with tidal observations. Tide gauge data may be both from near and far fields; invalidating the identification of a contribution from local submarine mass failure (SMF). "Green's functions" used for assimilating tsunami observations in source models may be based on non-dispersive equations which may not capture the correct phase speed of shorter wave trains, e.g. such as generated by SMFs. A major problem with identifying the generating mechanism is when tsunami magnitude is large compared to the earthquake such as with 'tsunami' earthquakes and where the earthquake is not slow, as in Papua New Guinea in 1998, where a SMF was identified as the tsunami source. However, with most great earthquakes, e.g. the Indian Ocean, it is accepted from the outset that the only source is the earthquake. Another, more recent event is the Tohoku-oki earthquake and tsunami that devastated the northeast of Japan in March 2011; although with some unusual rupture characteristics it is not a tsunami earthquake. There are now a number of simulations published, that mostly assume an earthquake source but that fail the simple test of using an independently defined earthquake rupture mechanism that can be validated by onshore fieldwork, tide gauge and offshore buoy data. Here we briefly consider some of the existing source models and present new tsunami simulations based on a combination of a FEM coseismic source and a SMF. We show that the multi-source tsunami agrees well with the available tide gauge data and field observations onshore and the wave data from offshore buoys.

Tappin, David; Grilli, Stephan; Harris, Jeffrey; Masterlark, Timothy; Kirby, James; Shi Shi, Fengyan; Ma, Gangfeng

2013-04-01

210

Near-Field Tsunami Edge Waves and Complex Earthquake Rupture  

Science.gov (United States)

The effect of distributed coseismic slip on progressive, near-field edge waves is examined for continental shelf tsunamis. Detailed observations of edge waves are difficult to separate from the other tsunami phases that are observed on tide gauge records. In this study, analytic methods are used to compute tsunami edge waves distributed over a finite number of modes and for uniformly sloping bathymetry. Coseismic displacements from static elastic theory are introduced as initial conditions in calculating the evolution of progressive edge-waves. Both simple crack representations (constant stress drop) and stochastic slip models (heterogeneous stress drop) are tested on a fault with geometry similar to that of the M w = 8.8 2010 Chile earthquake. Crack-like ruptures that are beneath or that span the shoreline result in similar longshore patterns of maximum edge-wave amplitude. Ruptures located farther offshore result in reduced edge-wave excitation, consistent with previous studies. Introduction of stress-drop heterogeneity by way of stochastic slip models results in significantly more variability in longshore edge-wave patterns compared to crack-like ruptures for the same offshore source position. In some cases, regions of high slip that are spatially distinct will yield sub-events, in terms of tsunami generation. Constructive interference of both non-trapped and trapped waves can yield significantly larger tsunamis than those that produced by simple earthquake characterizations.

Geist, Eric L.

2013-09-01

211

Assessing the Near-Field Tsunami Hazard for the Pacific Northwest in View of the 2011 Japan Tsunami  

Science.gov (United States)

Direct energy estimation using real-time deep-ocean pressure measurements suggested the tsunami energy is only about 0.1% of the seismic radiation energy released by the 11 March 2011 Tohoku-Oki M9.0 earthquake. This real-time estimation allowed NOAA Center for Tsunami Research (NCTR) to accurately provide experimental forecast of the tsunami impact for U.S. coastline in real time during the Japanese tsunami. It also led to quick, yet accurate, modeling of the tsunami inundation in Japanese coastline within hours after the event. The flooding limits computed with 11 inundation models that cover the entire east coastline of Japan agree well with observations. The computed tsunami runup height is up to 40 m, and the tsunami-height distribution along Japanese coastline is consistent with post-tsunami survey. These computational results will be compared with tsunami measurements and post-tsunami measurements, in light of a real-time tsunami source determined directly from deep-ocean tsunami measurements independent of any seismic data. Use of the forecast source scenario as input for tsunami inundation models for local coastlines shows promise for improved local tsunami forecast and warnings.The examples of the 2011 Japanese, as well as the 2010 Chilean, tsunamis will be used to illustrate the approaches to reducing the latency period for near-field tsunami forecasting. The catastrophic Japanese tsunami raised deep concerns about the tsunami impact in the U.S. Pacific Northwest (PNW), where a giant earthquake has been estimated to strike in the Cascadia within the next 50 years with a possibility of 10% to 15%. The similarity of tectonic settings and coastal environments between PNW and Sanriku, Japan may potentially result in comparable, or worse, disasters at PNW with what happened in Japan. To illustrate the similarity, we study the tsunami inundation impact along the coastline of PNW caused by a 500-year scenario on the Cascadia Subduction Zone (CSZ).

Wei, Y.; Titov, V. V.; Tang, L.; Chamberlin, C.

2011-12-01

212

Evaluation of coseismic and gravitational tsunami hazards in intraplate shelf seas: sensitivity modeling of the Dover Strait 1580 marine event  

Science.gov (United States)

On April 6, 1580, an earthquake of estimated local magnitude 5.8 occurred within the Dover Strait, between England and France. The shake was widely felt in England, France, Belgium, and the Low Countries, with much destruction and numerous casualties as far as Rouen (~200 km from the epicenter) and London (~150 km from the epicenter). Contemporaneous references even called it the 'London's earthquake'. Several independent witness accounts report that it was followed by a series of huge sea waves perhaps ascribable to a tsunami. Despite disagreement over this hypothesis among scholars, several recent geological and paleoseismological studies currently provide good constraints for testing the marine response to a range of plausible coseismic rupture scenarios occurring on faults of the Weald-Artois fault zone from a Mw5.5 earthquake to a Mw6.9. In addition, the hypothesis of aerial coastal landslides triggered by the shake along the chalk cliffs bordering the Dover Strait is also tested. Results obtained here highlight the importance of considering intraplate ruptures in tsunami hazard assessment plans, even when the probability of occurrence is low. They also underline the need for the thorough collection and accurate analysis of historical data when available.

Roger, J.; Gunnell, Y.; Ray, P.

2011-12-01

213

Tsunami Risk Management in Pacific Island Countries and Territories (PICTs): Some Issues, Challenges and Ways Forward  

Science.gov (United States)

The Pacific is well known for producing tsunamis, and events such as the 2011 T?hoku-oki, Japan disaster demonstrate the vulnerability of coastal communities. We review what is known about the current state of tsunami risk management for Pacific Island countries and territories (PICTs), identify the issues and challenges associated with affecting meaningful tsunami disaster risk reduction (DRR) efforts and outline strategies and possible ways forward. Small island states are scattered across the vast Pacific region and these states have to varying degrees been affected by not only large tsunamis originating in circum-Pacific subduction zones, but also more regionally devastating events. Having outlined and described what is meant by the risk management process, the various problems associated with our current understanding of this process are examined. The poorly understood hazard related to local, regional and distant sources is investigated and the dominant focus on seismic events at the expense of other tsunami source types is noted. We reflect on the challenges of undertaking numerical modelling from generation to inundation and specifically detail the problems as they relate to PICTs. This is followed by an exploration of the challenges associated with mapping exposure and estimating vulnerability in low-lying coastal areas. The latter part of the paper is devoted to exploring what mitigation of the tsunami risk can look like and draw upon good practice cases as exemplars of the actions that can be taken from the local to regional level. Importantly, given the diversity of PICTs, no one approach will suit all places. The paper closes by making a series of recommendations to assist PICTs and the wider tsunami research community in thinking through improvements to their tsunami risk management processes and the research that can underpin these efforts.

Dominey-Howes, Dale; Goff, James

2013-09-01

214

Tsunami forecast for Bulgarian coasts of the Black Sea  

Science.gov (United States)

Tsunami hazard in the Black Sea is considered low to moderate but not negligible. At present, New European Tsunami Catalogue counts 29 historical tsunami events in the Black Sea, 22 of which are considered as reliable. Four of them affected Bulgarian coast including a strong earthquakes event 544/545 of offshore Varna. Here we discuss a forecast of possible tsunami wave heights at Bulgarian coasts of the Black Sea. In order to do that, prognostic numerical simulations of 55 tsunami events in the Baltic Sea has been performed. All tsunami sources are uniformly distributed in the Black Sea basin. The results of prognostic numerical simulations are compared with the results of numerical modelling of two instrumentally measured historical events (1939 and 1966) and with the data of instrumental measurements. On this basis a preliminary forecast of tsunami wave heights along the Bulgarian coast of the Black Sea is given.

Didenkulova, Ira; Zaitsev, Andrey; Pelinovsky, Efim; Ranguelov, Boyko

2013-04-01

215

What Causes Tsunamis?  

Science.gov (United States)

On December 26, 2004, a disastrous tsunami struck many parts of South Asia. The scope of this disaster has resulted in an outpouring of aid throughout the world and brought attention to the science of tsunamis. "Tsunami" means "harbor wave" in Japanese, and the Japanese have a long history of tsunamis. The word "tsunami" brings to mind one…

Mogil, H. Michael

2005-01-01

216

Animation of the July 17, 1998, Papua New Guinea Tsunami  

Science.gov (United States)

On July 17, 1998, an earthquake registering 7.1 on the richter scale caused a tsunami along the coast of Papua New Guinea, wiping out two villages. The US Geological Survey (USGS) provides a model of the tsunami along with background information and news stories about the event. The animation is available in four formats and resolutions. Those who want to learn more about tsunamis can take advantage of the site's links under the heading General Information about Tsunamis.

217

Tsunami lung.  

UK PubMed Central (United Kingdom)

We encountered three cases of lung disorders caused by drowning in the recent large tsunami that struck following the Great East Japan Earthquake. All three were females, and two of them were old elderly. All segments of both lungs were involved in all the three patients, necessitating ICU admission and endotracheal intubation and mechanical ventilation. All three died within 3 weeks. In at least two cases, misswallowing of oil was suspected from the features noted at the time of the detection. Sputum culture for bacteria yielded isolation of Stenotrophomonas maltophilia, Legionella pneumophila, Burkholderia cepacia, and Pseudomonas aeruginosa. The cause of tsunami lung may be a combination of chemical induced pneumonia and bacterial pneumonia.

Inoue Y; Fujino Y; Onodera M; Kikuchi S; Shozushima T; Ogino N; Mori K; Oikawa H; Koeda Y; Ueda H; Takahashi T; Terui K; Nakadate T; Aoki H; Endo S

2012-04-01

218

SEDIMENT CHARACTERISTICS OF THE M-9 TSUNAMI EVENT BETWEEN RAMESWARAM AND THOOTHUKUDI, GULF OF MANNAR, SOUTHEAST COAST OF INDIA  

Directory of Open Access Journals (Sweden)

Full Text Available On 26th December, 2004, a massive earthquake occurred NW of Sumatra in the seismically active zone close to Sunda Trench at a water depth of about 1300m and with an epicenter located at a shallow depth of 10km below the ocean floor. This earthquake triggered tsunami waves in the Indian Ocean and hit most of the Tamilnadu coast, with wave height varying from 3 to 10m. In the study area dunes were breached. Erosional channels were created. Inundation in the study area ranges between 10 and 600m from the shoreline. The inundated sediment thickness varies from 1 to 30cm and was well preserved. Sediments thickness gets reduced landwards and occurs as set of layers. The sediments were fresh, grey to dark grey in color.

S.R.Singarasubramanian; M.V.Mukesh; K.Manoharan; S.Murugan; D.Bakkiaraj; A.John Peter; P.Seralathan

2006-01-01

219

Laboratory investigations of the effects of geologic heterogeneity on groundwater salinization and flush-out times from a tsunami-like event.  

UK PubMed Central (United Kingdom)

This intermediate scale laboratory experimental study was designed to improve the conceptual understanding of aquifer flushing time associated with diffuse saltwater contamination of coastal aquifers due to a tsunami-like event. The motivation comes from field observations made after the tsunami in December, 2004 in South Asia. The focus is on the role and effects of heterogeneity on flushing effectiveness. A scheme that combines experimentation in a 4.8m long laboratory tank and numerical modeling was used. To demonstrate the effects of geologic heterogeneity, plume migration and flushing times were analyzed in both homogeneous and layered media and under different boundary conditions (ambient flow, saltwater infiltration rate, freshwater recharge). Saltwater and freshwater infiltrations imitate the results of the groundwater salinization from the tsunami and freshening from the monsoon rainfall. The saltwater plume behavior was monitored both through visual observations (digital photography) of the dyed salt water and using measurements taken from several electrical conductivity sensors installed through the tank walls. The variable-density, three dimensional code HST3D was used to simulate the tank experiments and understand the fate and movement of the saltwater plume under field conditions. The results from the tank experiments and modeling demonstrated that macro-scale heterogeneity significantly influenced the migration patterns and flushing times of diffuse saltwater contamination. Ambient flow had a direct influence on total flush-out time, and heterogeneity impacted flush-out times for the top part of the tank and total flush-out times. The presence of a continuous low-permeability layer caused a 40% increase in complete flush-out time due to the slower flow of salt water in the low-permeability layer. When a relatively small opening was introduced in the low-permeability layer, salt water migrated quickly into a higher-permeable layer below causing a reduction in flush-out time. Freshwater recharge caused an early dilution of salt water in the top part of the tank in the case of a layered media, but also pushed the saltwater plume into the low-permeability layer which led to increased total flush-out times.

Vithanage M; Engesgaard P; Jensen KH; Illangasekare TH; Obeysekera J

2012-08-01

220

MODELING THE 1958 LITUYA BAY MEGA-TSUNAMI, II  

Directory of Open Access Journals (Sweden)

Full Text Available Lituya Bay, Alaska is a T-Shaped bay, 7 miles long and up to 2 miles wide. The two arms at the head of the bay, Gilbert and Crillon Inlets, are part of a trench along the Fairweather Fault. On July 8, 1958, an 7.5 Magnitude earthquake occurred along the Fairweather fault with an epicenter near Lituya Bay.A mega-tsunami wave was generated that washed out trees to a maximum altitude of 520 meters at the entrance of Gilbert Inlet. Much of the rest of the shoreline of the Bay was denuded by the tsunami from 30 to 200 meters altitude.In the previous study it was determined that if the 520 meter high run-up was 50 to 100 meters thick, the observed inundation in the rest of Lituya Bay could be numerically reproduced. It was also concluded that further studies would require full Navier-Stokes modeling similar to those required for asteroid generated tsunami waves.During the Summer of 2000, Hermann Fritz conducted experiments that reproduced the Lituya Bay 1958 event. The laboratory experiments indicated that the 1958 Lituya Bay 524 meter run-up on the spur ridge of Gilbert Inlet could be caused by a landslide impact.The Lituya Bay impact landslide generated tsunami was modeled with the full Navier- Stokes AMR Eulerian compressible hydrodynamic code called SAGE with includes the effect of gravity.

Charles L. Mader; Michael L. Gittings

2002-01-01

 
 
 
 
221

ZONAS OSCURAS EN EL SISTEMA DE ALARMA DE ADVERTENCIA DE TSUNAMI EN CHILE/ DARK ZONES IN ALARM SYSTEM OF TSUNAMI OF WARNING OF TSUNAMI IN CHILE  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish El territorio chileno cuenta con alrededor de 80.000 km de costa considerando el territorio insular, un dato relevante al momento de considerar la ocurrencia de un tsunami. Las autoridades chilenas, conscientes de este extenso territorio marítimo, han desarrollado un sistema de alerta de tsunami como una responsabilidad estatal y han depositado su control a la oficina nacional de emergencia ? ministerio del interior (ONEMI) y en el servicio hidrográfico y ocean (more) ográfico de la armada de Chile (SHOA). En este artículo hemos realizado experiencias con el objetivo de activar los sistemas de advertencias generando eventos telúricos ficticios y/o eventos telúricos históricos capaces de desatar eventos de tsunami. También se ha propuesto una hipótesis de trabajo que permita, a través de los procedimientos establecidos por ley de la República de Chile, monitorear los tiempos de respuestas de los organismos estatales. Nuestro trabajo de investigación entrega resultados que nos permiten afirmar que existen zonas para eventos hipotéticos que podrían generar tsunamis a los cuales el sistema de alerta no sería eficiente en reaccionar. Para llevar a cabo esta investigación hemos utilizado un software llamado SLAT, basado en ecuaciones simplificadas de propagación de una onda de tsunami que nos permite obtener resultados rápidos y además hemos sometido a prueba el sistema con datos oficiales en los cuales se ha demostrado que el sistema de alerta no fue capaz de reaccionar al evento Atico 8,4 M. ocurrido en Perú. Abstract in english The Chilean territory has an extensive coastline -about 80.000 km of coast including the territory of its islands ? which is an important fact to consider in the event of the occurrence of a tsunami. The Chilean authorities, fully aware of the vast maritime territory, have developed a tsunami warning system. This system constitutes a state responsibility, and its control has been entrusted to the national emergency office - ministry of interior (ONEMI) and hydrographic a (more) nd oceanographic service of Chilean navy (SHOA). This article deals with experiences carried out in order to activate the warning systems, generating fictional telluric events and / or historical telluric events capable of triggering tsunami occurrences. It also proposes a working hypothesis that will allow monitoring the response of the state agencies, through the procedures established by law in the Republic of Chile. Our research delivers results that allow us to affirm that there are areas for hypothetical events that could generate tsunamis in which the To carry out this research we have used a software called STLAT based on simplified equations of the propagation of a tsunami wave, which has allowed us to get quick results. We have also carried out tests with official data which have shown that the alarm system was not able to respond appropriately to the 8.4 M Atico event that occurred in Peru in 2001.

Alvarez, Gabriel; Ramirez, Jorge; Paredes, Lorena; Canales, Miguel

2010-12-01

222

Tsunami diaries  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Inspired by recent discussion on how Serbian media influenced allegedly indifferent reaction of the public to the aftermath of tsunami, this paper examines the role of electronic media in Serbia, television in particular, in regard to their function as a central communication channel for acquiring k...

Radovi? Sr?an

223

What Is a Tsunami?  

Science.gov (United States)

... Story Smile Style Game WHAT? What is a tsunami? Tsunamis are giant sea waves. They can be ... will destroy anything in their way. Why are tsunamis so destructive? During a normal storm or hurricane, ...

224

Propagation modelling of the February 2010 Chilean tsunami over French-Polynesia on a massive parallel processing system  

Science.gov (United States)

On the 27th February 2010, an earthquake with magnitude of 8.8 occurred 115 kilometers NNE of Concepción, Chile. The French Polynesia Tsunami Warning System (CPPT) , located on Tahiti, notified French Polynesia authorities through tsunami information bulletin about a red tsunami warning level, the highest warning level. When major earthquakes occurring in the Nazca subduction zone have magnitudes such large, historical tsunami events showed that the most concerned islands in French Polynesia are the Marquesas Islands that present few outer reefs, more gradual bottom slopes and large bays. The tsunami travel time to Tahiti is about three hours and about four hours to reach Marquesas islands where respectively we observed near the coast a maximum elevation wave about 0.3 and 3.0 meter on the tide-gauges. In this context, the associated tsunami has been modelled over Pacific ocean using multiple grids with different sizes to test the accuracy and real-time local forecast possibilities that offer our model using a parallel implementation. The water surface initialisation has been computed from Okada's formulation, using seismic parameters of the CPPT. Tsunami propagation has been modelled by a finite-difference numerical model solving shallow water equations. The model is implemented using the domain decomposition technique in conjunction with message passing interface (MPI). The values of tsunami amplitudes, flow velocities and arrival times are compared to the observed data in French Polynesia. This model is developed in the framework of the CPPT and the future French Mediterranean Tsunami Warning System part of the North-eastern Atlantic and Mediterranean Tsunami Warning System (NEAMTWS) to enhance the pre-computed generation/propagation forecast database.

Jamelot, A.; Hebert, H.; Reymond, D.; Allgeyer, S.; Heinrich, P.

2010-05-01

225

MadGraph/MadEvent. The new web generation  

International Nuclear Information System (INIS)

[en] The new web-based version of the automatized process and event generator MadGraph/MadEvent is now available. Recent developments are: New models, notably MSSM, 2HDM and a framework for addition of user-defined models, inclusive sample generation and on-line hadronization and detector simulation. Event generation can be done on-line on any of our clusters. (author)

2007-01-01

226

Tsunami watch and warning in Fiji  

International Nuclear Information System (INIS)

The tsunami warning system needs further development in Fiji. The MRD earthquake and tsunami plan of action needs to be tested and appropriate authorities drilled in putting this plan into practice. It also needs to be supplemented with an alarm system such that people near the coasts, especially in built-up areas such as Suva can be made aware of impending tsunami danger. The plan of action becomes virtually ineffective when dealing with locally generated tsunamis and for this we have to rely on public education as it is not yet possible or practical to devise a warning system which can be activated within adequate time. 3 refs, 2 figs, 1 tab.

1989-01-01

227

THE TSUNAMI HISTORY OF GUAM: 1849-1993  

Directory of Open Access Journals (Sweden)

Full Text Available The great (Mw 8.1) tsunamigenic earthquake of August 8, 1993, about 50 km to the east of Guam, has created renewed interest in the tsunami hazard for the island of Guam. We examine this hazard from two perspectives--historical and mechanistic. Guam has had only three tsunamis causing damage at more than one location--in 1849, 1892, and in 1993, and only two to six other locally-generated tsunamis which were observed on the island in the past 200 years. Five of these six events have low validities and may not be reports of true tsunami. On the other hand, dozens of storm surges related to typhoons have caused millions of dollars of damage on Guam. The island of Guam is located west of the Marianas Trench. The trench is caused by the subduction of old, cold, and dense lithosphere of the Pacific plate under the Philippine plate. Steeply dipping old material is unlikely to trigger tsunamis because (1) the two plates are decoupled and (2) the motion is too slow to allow large amounts of stress to build up before earthquakes occur, resulting in less violent earthquakes. A small section of the Marianas Trench near Guam, however, has shallow subduction. This is where the 1993 event occurred, and a quiet area south of this may be the site of a similar future tsunamigenic earthquake. Most of the damage from a local tsunami would occur on the relatively unpopulated east coast; the likelihood of a local tsunami from the west is minimal. However, a repeat of the 1848 tsunami with a southern source could affect both the east and west coasts. The 1993 earthquake occurred coincident with the passage of Typhoon Steve. We show that this may not be coincidental as there is a substantial statistical correlation between earthquakes and typhoons at Guam. The close encounter of a typhoon with Guam doubles the probability of an earthquake with magnitude greater than 5.0 occurring on that day.

James F. Lander; Lowell S. Whiteside; Paul Hattori

2002-01-01

228

Tsunami Source of the 2010 Mentawai, Indonesia Earthquake Inferred from Tsunami Field Survey and Waveform Modeling  

Science.gov (United States)

The 2010 Mentawai earthquake (magnitude 7.7) generated a destructive tsunami that caused more than 500 casualties in the Mentawai Islands, west of Sumatra, Indonesia. Seismological analyses indicate that this earthquake was an unusual "tsunami earthquake," which produces much larger tsunamis than expected from the seismic magnitude. We carried out a field survey to measure tsunami heights and inundation distances, an inversion of tsunami waveforms to estimate the slip distribution on the fault, and inundation modeling to compare the measured and simulated tsunami heights. The measured tsunami heights at eight locations on the west coasts of North and South Pagai Island ranged from 2.5 to 9.3 m, but were mostly in the 4-7 m range. At three villages, the tsunami inundation extended more than 300 m. Interviews of local residents indicated that the earthquake ground shaking was less intense than during previous large earthquakes and did not cause any damage. Inversion of tsunami waveforms recorded at nine coastal tide gauges, a nearby GPS buoy, and a DART station indicated a large slip (maximum 6.1 m) on a shallower part of the fault near the trench axis, a distribution similar to other tsunami earthquakes. The total seismic moment estimated from tsunami waveform inversion was 1.0 × 1021 Nm, which corresponded to Mw 7.9. Computed coastal tsunami heights from this tsunami source model using linear equations are similar to the measured tsunami heights. The inundation heights computed by using detailed bathymetry and topography data and nonlinear equations including inundation were smaller than the measured ones. This may have been partly due to the limited resolution and accuracy of publically available bathymetry and topography data. One-dimensional run-up computations using our surveyed topography profiles showed that the computed heights were roughly similar to the measured ones.

Satake, Kenji; Nishimura, Yuichi; Putra, Purna Sulastya; Gusman, Aditya Riadi; Sunendar, Haris; Fujii, Yushiro; Tanioka, Yuichiro; Latief, Hamzah; Yulianto, Eko

2013-09-01

229

EL TERREMOTO Y POSTERIOR TSUNAMI DEL 26 DE DICIEMBRE DE 2004 EN INDONESIA  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english A short compilation of the cause, characteristics and effects of the tsunami generated on the 26 of December of 2004 in Indonesia is presented here. The general context of generation of this phenomena is illustrated together with the tectonic environment in which this tsunami in particular was produced. Finally, a brief introduction to tsunamis in Colombia including tsunami cases and areas of higher tsunami hazard is considered.

ESTRADA ROLDÁN, BEATRIZ ELENA; FARBIARZ FARBIARZ, JOSEF

2005-03-01

230

Simulation of space-borne tsunami detection using GNSS-Reflectometry applied to tsunamis in the Indian Ocean  

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Full Text Available Within the German-Indonesian Tsunami Early Warning System project GITEWS (Rudloff et al., 2009), a feasibility study on a future tsunami detection system from space has been carried out. The Global Navigation Satellite System Reflectometry (GNSS-R) is an innovative way of using reflected GNSS signals for remote sensing, e.g. sea surface altimetry. In contrast to conventional satellite radar altimetry, multiple height measurements within a wide field of view can be made simultaneously. With a dedicated Low Earth Orbit (LEO) constellation of satellites equipped with GNSS-R, densely spaced sea surface height measurements could be established to detect tsunamis. This simulation study compares the Walker and the meshed comb constellation with respect to their global reflection point distribution. The detection performance of various LEO constellation scenarios with GPS, GLONASS and Galileo as signal sources is investigated. The study concentrates on the detection performance for six historic tsunami events in the Indian Ocean generated by earthquakes of different magnitudes, as well as on different constellation types and orbit parameters. The GNSS-R carrier phase is compared with the PARIS or code altimetry approach. The study shows that Walker constellations have a much better reflection point distribution compared to the meshed comb constellation. Considering simulation assumptions and assuming technical feasibility it can be demonstrated that strong tsunamis with magnitudes (M) ?8.5 can be detected with certainty from any orbit altitude within 15–25 min by a 48/8 or 81/9 Walker constellation if tsunami waves of 20 cm or higher can be detected by space-borne GNSS-R. The carrier phase approach outperforms the PARIS altimetry approach especially at low orbit altitudes and for a low number of LEO satellites.

R. Stosius; G. Beyerle; A. Helm; A. Hoechner; J. Wickert

2010-01-01

231

Tsunami deposits of the Shikotan earthquake of 1994  

Science.gov (United States)

This paper describes the results of the grain-size and mineralogical studies of the deposits of the tsunami of 1994 on Shikotan, Tanfil’ev, and Kunashir islands. The studies were carried out within the portions of the coast with different configurations, geomorphologic structures, lithodynamical environments, and character of the tsunami manifestation. The composition of the tsunami deposits is shown to be controlled mainly by erosion-accumulative processes during the tsunami events and is in many respects inherited from the matter sources. The tsunami deposits contain marine diatom species, whose richest assemblages were found within the areas where the material from the underwater coastal slope was redeposited. The data concerning the deposits of earlier historical tsunamis encountered in the same cross sections are discussed too. Their examination points to a similar development of the erosional-accumulative processes during tsunami events with the same intensity and an entrainment of the matter from the same sources.

Razzhigaeva, N. G.; Ganzei, L. A.; Grebennikova, T. A.; Kharlamov, A. A.; Il'Ev, A. Ya.; Kaistrenko, V. M.

2007-08-01

232

The open ocean energy decay of three recent trans-Pacific tsunamis  

Science.gov (United States)

The 2009 Samoa (Mw 8.1), 2010 Chile (8.8), and 2011 Tohoku (9.0) earthquakes generated destructive tsunamis recorded by a large number of DART stations in the Pacific Ocean. High-resolution (15 s) DART records yield mean energy decay times for these events of 17.3, 24.7, and 24.6 h, respectively. We attribute these differences to the frequency content of the tsunamis. Specifically, the Samoa tsunami was a "high-frequency" event with periods of 2-30 min whereas the Chile and Tohoku tsunamis were "broad-band" events with periods of 2-180 min. Differences in frequency content are linked to differences in the source parameters: Samoa was a relatively small deep-water earthquake while Chile and Tohoku were extensive shallow-water earthquakes. Frequency-dependent analysis of the Chile and Tohoku tsunamis indicates that shorter period waves attenuate much faster than longer-period waves (decay times range from 15 h for 2-6 min waves to 29 h for 60-180 min waves).

Rabinovich, Alexander B.; Candella, RogéRio N.; Thomson, Richard E.

2013-06-01

233

Unusually large earthquakes inferred from tsunami deposits along the Kuril trench  

Science.gov (United States)

The Pacific plate converges with northeastern Eurasia at a rate of 8-9 m per century along the Kamchatka, Kuril and Japan trenches. Along the southern Kuril trench, which faces the Japanese island of Hokkaido, this fast subduction has recurrently generated earthquakes with magnitudes of up to ???8 over the past two centuries. These historical events, on rupture segments 100-200 km long, have been considered characteristic of Hokkaido's plate-boundary earthquakes. But here we use deposits of prehistoric tsunamis to infer the infrequent occurrence of larger earthquakes generated from longer ruptures. Many of these tsunami deposits form sheets of sand that extend kilometres inland from the deposits of historical tsunamis. Stratigraphic series of extensive sand sheets, intercalated with dated volcanic-ash layers, show that such unusually large tsunamis occurred about every 500 years on average over the past 2,000-7,000 years, most recently ???350 years ago. Numerical simulations of these tsunamis are best explained by earthquakes that individually rupture multiple segments along the southern Kuril trench. We infer that such multi-segment earthquakes persistently recur among a larger number of single-segment events.

Nanayama, F.; Satake, K.; Furukawa, R.; Shimokawa, K.; Atwater, B. F.; Shigeno, K.; Yamaki, S.

2003-01-01

234

TOWARD INDONESIAN TSUNAMI EARLY WARNING SYSTEM BY USING RAPID RUPTURE DURATIONS CALCULATION  

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Full Text Available Indonesia has an Indonesian Tsunami Early Warning System (Ina-TEWS) since 2008. The Ina-TEWS has used automatic processing on hypocenter; Mwp, Mw (mB) and Mj. If earthquake occurred in Ocean, depth 7, then Ina-TEWS announce early warning that the earthquake can generate tsunami. However, the announcement of the Ina-TEWS is still not accuracy. Purpose of this study is to estimate earthquake rupture duration of large Indonesia earthquakes that occurred in Indian Ocean, Java, Timor Sea, Banda Sea, Arafura Sea and Pacific Ocean using a direct procedure and software developed Lomax and Michelini for rapid assessment of earthquake tsunami potential by deriving two simple measures from vertical component broadband P-wave velocity record. The first is the high-frequency apparent rupture duration, Tdur which may be related to can be related to the critical parameters rupture length (L), depth (z), and shear modulus (?). The second is a confirmation of the earlier finding by Lomax and Michelini, namely that the rupture duration has a stronger influence to generate tsunami than Mw and Depth. We analyzed at least 510 vertical seismogram recorded by GEOFON-IA and IRIS-DMC networks. Our analysis shows that the seismic potency, LWD, which is more obviously related to capability to generate a tsunami than former. The larger Tdur the larger is the seismic potency LWD because Tdur is proportional to L/vr (with vr – rupture velocity). We also suggest that tsunami potential is not directly related to the faulting type of source and for events that have rupture duration greater than 50 s, the earthquakes generated tsunami. With available real-time seismogram data, rapid calculation, rupture duration discriminant can be completed within 3 to 8 min after the P-onset.

M. Adlazim

2011-01-01

235

COMMENT ON: TSUNAMIS AND TSUNAMI-LIKE WAVES OF THE EASTERN UNITED STATES BY PATRICIA A. LOCKRIDGE, LOWELL S. WHITESIDE AND JAMES F. LANDER WITH RESPECT TO THE NOVEMBER 18, 1929 EARTHQUAKE AND ITS TSUNAMI  

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Full Text Available This most valuable compilation by Patricia Lockridge et al. (2002) covers a wide range of tsunamis and tsunami-like events ranging from marine tectonic, volcanic, and landslide tsunamis to possible meteorologic tsunami-like events. Lockridge et al.'s (2002) massive text table (pp. 124-141) entitled "Description of Events" covers events from 1668 to 1992. The 2002 paper in Science of Tsunami Hazards was clearly intended to be an update of, an extension to, and a sequel to, the first east coast and Caribbean tsunami compilations contained in Lander and Lockridge's 1989 National Geophysical Data Center volume United States Tsunamis (including United States Possessions) 1690-1988.The Lockridge et al. (2002) compilation contains a small error with respect to the 1929 "Grand Banks" Earthquake and Tsunami of which I may be cause in part. In addition the tsunami histories of oceans without a tsunami warning system will be now receiving much closer attention, including historic events in the Atlantic Ocean given the events of December 26, 2004 and March 18, 2005 in the Indian Ocean; both the Atlantic and the Indian Oceans have no tsunami warning system and have an incomplete tsunami history.

Alan Ruffman

2005-01-01

236

Tsunami Hazard Evaluation for the East Coast of Korea by using Empirical Data  

International Nuclear Information System (INIS)

In this study, a tsunami hazard curve was determined for a probabilistic safety assessment (PSA) induced tsunami event in Nuclear Power Plant site. A Tsunami catalogue was developed by using historical tsunami record which happen before 1900 and instrumental tsunami record after 1900. For the evaluation of return period of tsunami run-up height, power-law, uppertruncated power law and exponential function were considered for the assessment of regression curves and compared with each result. Although the total tsunami records were only 9 times at the east coast of Korea during tsunami catalogue, there was no such research like this about tsunami hazard curve evaluation and this research lay a cornerstone for probabilistic tsunami hazard assessment (PTHA) in Korea

2010-01-01

237

A revision of the 1783–1784 Calabrian (southern Italy) tsunamis  

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Full Text Available Southern Italy is one of the most tsunamigenic areas in the Mediterranean basin, having experienced during centuries a large number of tsunamis, some of which very destructive. In particular, the most exposed zone here is the Messina Straits separating the coasts of Calabria and Sicily that was the theatre of the strongest Italian events. In 1783–1785 Calabria was shaken by the most violent and persistent seismic crisis occurred in the last 2000 years. Five very strong earthquakes, followed by tsunamis, occurred in a short interval of time (February–March 1783), causing destruction and a lot of victims in a vast region embracing the whole southern Calabria and the Messina area, Sicily. In this study we re-examined these events by taking into account all available historical sources. In particular, we focussed on the 5 and 6 February 1783 tsunamis, that were the most destructive. As regards the 5 February event, we found that it was underestimated and erroneously considered a minor event. On the contrary, the analysis of the sources revealed that in some localities the tsunami effects were quite strong. The 6 February tsunami, the strongest one of the sequence, was due to a huge earthquake-induced rockfall and killed more than 1500 people in the Calabrian village of Scilla. For this event the inundated area and the runup values distribution were estimated. Further, the analysis of the historical sources allowed us to find three new tsunamis that passed previously unnoticed and that occurred during this seismic period. The first one occurred a few hours before the large earthquake of 5 February 1783. The second was generated by a rockfall on 24 March 1783. Finally, the third occurred on 9 January 1784, probably due to a submarine earthquake.

L. Graziani; A. Maramai; S. Tinti

2006-01-01

238

Long-Term Tsunami Data Archive Supports Tsunami Forecast, Warning, Research, and Mitigation  

Science.gov (United States)

In response to the 2004 Indian Ocean tsunami, the United States began a careful review and strengthening of its programs aimed at reducing the consequences of tsunamis. Several reports and calls to action were drafted, including the Tsunami Warning and Education Act (Public Law 109-424) signed into law by the President in December 2006. NOAA’s National Geophysical Data Center (NGDC) and co-located World Data Center for Geophysics and Marine Geology (WDC-GMG) maintain a national and international tsunami data archive that fulfills part of the P.L. 109-424. The NGDC/WDC-GMG long-term tsunami data archive has expanded from the original global historical event databases and damage photo collection, to include tsunami deposits, coastal water-level data, DART™ buoy data, and high-resolution coastal DEMs. These data are used to validate models, provide guidance to warning centers, develop tsunami hazard assessments, and educate the public about the risks from tsunamis. In this paper we discuss current steps and future actions to be taken by NGDC/WDC-GMG to support tsunami hazard mitigation research, to ultimately help save lives and improve the resiliency of coastal communities.

Dunbar, Paula K.; Stroker, Kelly J.; Brocko, Vanita R.; Varner, Jesse D.; McLean, Susan J.; Taylor, Lisa A.; Eakins, Barry W.; Carignan, Kelly S.; Warnken, Robin R.

2008-12-01

239

Les Houches Squared Event Generator for the NMSSM.  

Science.gov (United States)

We present a generic framework for event generation in the Next-to- Minimal Supersymmetric Standard Model (NMSSM), including the full chain of production process, resonance decays, parton showering, hadronization, and hadron decays. The framework at prese...

A. Pukhov P. Skands

2005-01-01

240

Exotic processes at HERA: The event generator COMPOS  

Energy Technology Data Exchange (ETDEWEB)

The program COMPOS is able to generate events of non standard physics in electron proton collisions. Some details of the implementation as well as the underlying physics of the models are described. (orig.).

Koehler, T. (RWTH Aachen, I. Physikalisches Institut (Germany))

1992-04-01

 
 
 
 
241

Exotic processes at HERA: The event generator COMPOS  

International Nuclear Information System (INIS)

The program COMPOS is able to generate events of non standard physics in electron proton collisions. Some details of the implementation as well as the underlying physics of the models are described. (orig.)

1992-01-01

242

Tsunamis: Detecting, Simulating, and Chasing Them  

Energy Technology Data Exchange (ETDEWEB)

Tsunamis are gravitational oscillations of the water mass of an ocean basin set up by earthquakes, landslides, volcanic eruptions, or bolide impacts. They represent an exceptional hazard capable of inflicting death and destruction on a global scale. Because their waves travel at a relatively slow speed (typically 200 m/s or the speed of a jetliner), there exists an opportunity for warning, at least in the far field. We will review the basic physics of the tsunami wave, the relationship between seismic source and tsunami excitation, and the scientific bases underlying the mitigation, warning, computer simulation, and real time detection of tsunami waves. In particular, we will describe the development of robust discriminants in the near and far fields for tsunamis generated by earthquakes and landslides, and will give examples of field methods for the recovery of quantitative databases of inundation measurements.

Okal, Emile A. (Northwestern University)

2005-02-23

243

Effect of harbor modifications on the tsunami vulnerability of Crescent City, California  

Science.gov (United States)

Crescent City, California has experienced more damaging tsunami events in historic times than any other location on the West Coast of the United States. Thirty-one tsunamis have been observed at Crescent City since a tide gauge was established in 1933, including eleven events with maximum peak to trough wave range exceeding one meter and four that caused damage. The most damaging event occurred in 1964 as a result of the great Alaska earthquake. The ensuing tsunami flooded 29 city blocks and killed 11 in the Crescent City area. As a result of the 1964 tsunami and redevelopment projects, the Crescent City harbor was significantly modified in the early 1970s. A 200 x 300 meter small boat basin was carved into the preexisting shore line, a 123 meter dog leg extension was added to the central breakwater and significant deepening occurred on the eastern side of the harbor. In 2006, a Mw 8.3 earthquake in the Kuril Islands generated a moderate Pacific-wide tsunami. The only location with significant damage was the Crescent City harbor where strong currents damaged docks and boats, causing an estimated 9.2 million (US dollars) in damages. Strong currents estimated by the Harbor Master at 12 knots were observed near the entrance to the small boat basin. Past earthquakes from the northwestern Pacific including the 1933 M 8.3 Sanriku Japan earthquake may have produced similar amplitudes at Crescent City to the 2006 event but caused no damage. We have obtained the pre-modification harbor bathymetry and use the MOST model to compare tsunami water heights and current velocities for the 1933 and 2006 sources using modern and pre- modification bathymetry. We also examine model the 1964 inundation using the actual bathymetry and compare the results to numerical simulations that have only used the modern data.

Dengler, L.; Uslu, B.

2008-12-01

244

Could a 1755-Like Tsunami Reach the French Atlantic Coastline? Constraints from Twentieth Century Observations and Numerical Modeling  

Science.gov (United States)

The tsunami generated by the 1 November, 1755 earthquake off the coast of Portugal affected mainly the coastlines of the Iberian Peninsula and Northwest Morocco, but was also observed in some places along the North Atlantic coasts. To determine whether the event could have effected the French coastline, we conducted a study to search for signs of the tsunami in historical records from all tide gauge stations off the French Atlantic coast during the twentieth century, specifically for the 28 February, 1969 and the 26 May, 1975 tsunamis that were recorded by the Portuguese tide gauge network. Because many recordings are available in La Rochelle (located on the southwest coast of France), we focused our study on this harbor. The analysis of the tide gauge data shows no evidence for tsunamis in La Rochelle, neither in 1969 nor in 1975. To confirm this lack of tsunami signals, we used nonlinear, shallow water equations to compute the tsunami propagation to the French Atlantic coastline for both 1969 and 1975 events. Results obtained from these simulations confirm otherwise unnoticeable wave amplitudes at La Rochelle harbor. In a second step, tsunamis from three different scenarios for the 1755 earthquake were modeled to estimate the impact of such a tsunami on the French Atlantic coast, with a focus on La Rochelle harbor. A comparison of the functions of tide configuration was made in order to analyse the difference in impact. The results show that, while the harbor is poorly impacted, several areas (western part of the island of Ré and northern coast of the island of Oléron) may have experienced a moderate impact from 0.5 to 1 m, especially since the tide was high at the time of arrival, possibly causing local inundations in lowland areas.

Allgeyer, S.; Daubord, C.; Hébert, H.; Loevenbruck, A.; Schindelé, F.; Madariaga, R.

2013-09-01

245

Dispersive mudslide-induced tsunamis  

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Full Text Available A nonlinear nested model for mudslide-induced tsunamis is proposed in which three phases of the life of the wave, i.e. the generation, far-field propagation and costal run-up are described by means of different mathematical models, that are coupled through appropriate matching procedures. The generation and run-up dynamics are simulated through a nonlinear shallow-water model with movable lateral boundaries: in the generation region two active layers are present, the lower one describing the slide descending on a sloping topography. For the intermediate phase, representing wave propagation far from the generation region, the hydrostatic assumption is not assumed as appropriate in general and, therefore, a nonlinear model allowing for weak phase dispersion, namely a Kadomtsev-Petviashvili equation, is used. This choice is made in order to assess the relevance of dispersive features such as solitary waves and dispersive tails. It is shown that in some realistic circumstances dispersive mudslide-induced tsunami waves can be produced over relatively short, distances. In such cases the use of a hydrostatic model throughout the whole tsunami history turns out to give erroneous results. In particular, when solitary waves are generated during the tsunami propagation in the open sea, the resulting run-up process yields peculiar wave forms leading to amplified coastal inundations with respect to a mere hydrostatic context.

A. Rubino; S. Pierini; J. O. Backhaus

1998-01-01

246

Effects of Harbor Modification on Crescent City, California's Tsunami Vulnerability  

Science.gov (United States)

More damaging tsunamis have impacted Crescent City, California in historic times than any other location on the West Coast of the USA. Crescent City's harbor has undergone significant modification since the early 20th century, including construction of several breakwaters, dredging, and a 200 × 300 m2 small boat basin. In 2006, a M w 8.3 earthquake in the Kuril Islands generated a moderate Pacific-wide tsunami. Crescent City recorded the highest amplitudes of any tide gauge in the Pacific and was the only location to experience structural damage. Strong currents damaged docks and boats within the small boat basin, causing more than US 20 million in damage and replacement costs. We examine how modifications to Crescent City's harbor may have affected its vulnerability to moderate tsunamis such as the 2006 event. A bathymetric grid of the basin was constructed based on US Army Corps of Engineers soundings in 1964 and 1965 before the construction of the small boat basin. The method of splitting tsunamis was used to estimate tsunami water heights and current velocities at several locations in the harbor using both the 1964-1965 grid and the 2006 bathymetric grid for the 2006 Kuril event and a similar-sized source along the Sanriku coast of Japan. Model velocity outputs are compared for the two different bathymetries at the tide gauge location and at six additional computational sites in the harbor. The largest difference between the two grids is at the small boat basin entrance, where the 2006 bathymetry produces currents over three times the strength of the currents produced by the 1965 bathymetry. Peak currents from a Sanriku event are comparable to those produced by the 2006 event, and within the boat basin may have been higher. The modifications of the harbor, and in particular the addition of the small boat basin, appear to have contributed to the high current velocities and resulting damage in 2006 and help to explain why the 1933 M w 8.4-8.7 Sanriku tsunami caused no damage at Crescent City.

Dengler, Lori; Uslu, Burak

2011-06-01

247

State Emergency Response and Field Observation Activities in California (USA) during the March 11, 2011, Tohoku Tsunami  

Science.gov (United States)

This poster will present an overview of successes and challenges observed by the authors during this major tsunami response event. The Tohoku, Japan tsunami was the most costly to affect California since the 1964 Alaskan earthquake and ensuing tsunami. The Tohoku tsunami caused at least $50 million in damage to public facilities in harbors and marinas along the coast of California, and resulted in one fatality. It was generated by a magnitude 9.0 earthquake which occurred at 9:46PM PST on Thursday, March 10, 2011 in the sea off northern Japan. The tsunami was recorded at tide gages monitored by the West Coast/Alaska Tsunami Warning Center (WCATWC), which projected tsunami surges would reach California in approximately 10 hours. At 12:51AM on March 11, 2011, based on forecasted tsunami amplitudes, the WCATWC placed the California coast north of Point Conception (Santa Barbara County) in a Tsunami Warning, and the coast south of Point Conception to the Mexican border in a Tsunami Advisory. The California Emergency Management Agency (CalEMA) activated two Regional Emergency Operation Centers (REOCs) and the State Operation Center (SOC). The California Geological Survey (CGS) deployed a field team which collected data before, during and after the event through an information clearinghouse. Conference calls were conducted hourly between the WCATWC and State Warning Center, as well as with emergency managers in the 20 coastal counties. Coordination focused on local response measures, public information messaging, assistance needs, evacuations, emergency shelters, damage, and recovery issues. In the early morning hours, some communities in low lying areas recommended evacuation for their citizens, and the fishing fleet at Crescent City evacuated to sea. The greatest damage occurred in the harbors of Crescent City and Santa Cruz. As with any emergency, there were lessons learned and important successes in managing this event. Forecasts by the WCATWC were highly accurate. Exercises and workshops have enhanced communications between state and local agencies, and emergency managers are more educated about what to expect. Areas for improvement include keeping people out of the hazard area; educating the non-English speaking community; and reinforcing the long duration and unpredictable peak damaging waves of these events to emergency managers. The Governor proclaimed a state of emergency in six counties and the President declared a major disaster on April 18, 2011, allowing federal assistance to support repairs and economic recovery. Detailed evaluation of local maritime response activities, harbor damage, and measured and observed tsunami current velocity data will help the California Tsunami Program develop improved tsunami hazard maps and guidance for maritime communities. The state program will continue to emphasize the importance of both tsunami warnings and advisories, the unpredictable nature of each tsunami, and encourage public understanding of tsunamis to prepare and protect themselves in the future.

Miller, K. M.; Wilson, R. I.; Goltz, J.; Fenton, J.; Long, K.; Dengler, L.; Rosinski, A.; California Tsunami Program

2011-12-01

248

Developing tsunami fragility curves based on the satellite remote sensing and the numerical modeling of the 2004 Indian Ocean tsunami in Thailand  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The 2004 Indian Ocean tsunami damaged and destroyed numerous buildings and houses in Thailand. Estimation of tsunami impact to buildings from this event and evaluation of the potential risks are important but still in progress. The tsunami fragility curve is a function used to estimate the structura...

A. Suppasri; S. Koshimura; F. Imamura

249

Economic impacts of the SAFRR tsunami scenario in California: Chapter H in The SAFRR (Science Application for Risk Reduction) Tsunami Scenario  

Science.gov (United States)

This study evaluates the hypothetical economic impacts of the SAFRR (Science Application for Risk Reduction) tsunami scenario to the California economy. The SAFRR scenario simulates a tsunami generated by a hypothetical magnitude 9.1 earthquake that occurs offshore of the Alaska Peninsula (Kirby and others, 2013). Economic impacts are measured by the estimated reduction in California’s gross domestic product (GDP), the standard economic measure of the total value of goods and services produced. Economic impacts are derived from the physical damages from the tsunami as described by Porter and others (2013). The principal physical damages that result in disruption of the California economy are (1) about $100 million in damages to the twin Ports of Los Angeles (POLA) and Long Beach (POLB), (2) about $700 million in damages to marinas, and (3) about $2.5 billion in damages to buildings and contents (properties) in the tsunami inundation zone on the California coast. The study of economic impacts does not include the impacts from damages to roads, bridges, railroads, and agricultural production or fires in fuel storage facilities because these damages will be minimal with respect to the California economy. The economic impacts of damage to other California ports are not included in this study because detailed evaluation of the physical damage to these ports was not available in time for this report. The analysis of economic impacts is accomplished in several steps. First, estimates are made for the direct economic impacts that result in immediate business interruption losses in individual sectors of the economy due to physical damage to facilities or to disruption of the flow of production units (commodities necessary for production). Second, the total economic impacts (consisting of both direct and indirect effects) are measured by including the general equilibrium (essentially quantity and price multiplier effects) of lost production in other sectors by ripple effects upstream and downstream along the supply chain. An appropriate measure of the economic impacts on the California economy for the SAFRR tsunami scenario is the reduction in GDP. The economic impacts are first calculated without resilience, the ability of the economy to adjust to disruptions in ways that mute potential negative impacts. There are many types of resilience, including using existing inventories of materials, using unused capacity, conserving inputs, substituting for disrupted supplies, recapturing production after the disruption is restored, and many others. A method for estimating resilience, identified in the port system and sectors affected by property damages, is applied to indicate potential reductions of direct and total economic impacts. In this SAFRR tsunami scenario analysis of economic impacts to California, we implement established techniques used to model the economic impacts for two previous U.S. Geological Survey (USGS) scenarios: the southern California Shakeout earthquake (Rose and others, 2011) and the California ARkStorm severe winter storm (Sue Wing and others, written commun., 2013). For the SAFRR tsunami scenario, we reviewed the relevant studies that assess economic impacts from previous tsunami events affecting California and elsewhere and estimate the economic impacts of potential tsunami and other threats to POLA and POLB. To our knowledge, assessment of impacts to the California economy from distant source tsunamis does not exist. Previous tsunamis, including those from the 1960 Chile earthquake, the 1964 Alaska earthquake, the 2008 Chile earthquake and the 2011 Japan earthquake, had only relatively minor or very localized severe damage (such as that in Crescent City in 1964), and no studies of the economic impacts were completed. A rare study of the economic impacts of a tsunami event has recently been produced for the Tohoku earthquake and tsunami (Kajitani and others, 2013). Quarterly declines in Japan’s GDP are observed to peak at ?1.63 percent in the second quarter after the event and stagnate for the rest of th

Wein, Anne; Rose, Adam; Sue Wing, Ian; Wei, Dan

2013-01-01

250

How volcanic eruptions cause tsunamis  

Science.gov (United States)

This study investigates the effect of pyroclastic flows on tsunami generation. The authors analyzed several possible mechanisms that occur when the particle rich flows encounter water and conclude that the volume and density of the basal flow has a close correlation with the wave's amplitude and wavelength, which can be used to model the water movement in lakes, bays and oceans.

Watts, Phil; Waythomas, C. F.; Agu

251

REVIEW OF THE 1994 SKAGWAY, AKASKA TSUNAMI AND FUTURE PLANS  

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Full Text Available On November 3,1994 a nine meter amplitude submarine landslide-created tsunami with a resonate wave tram lasting about 30 minutes struck the Skagway, Alaska., watafiont causing extensive damage and loss of one life.Numerous scientists and engineers have studied the 1994 tsunami and at a workshop on the subject in Seattle, Washington, on October 30-3 1,2001, have generally concluded that large down inlet submarine landslide(s) created the tsunami. A general plan under the National Tsunami Hazard Mitigation Program was developed to start a study, which could lead to mitigation measures at Skagway with possible adaptability to other parts of theworkl with similar problems.This paper briefly overviews the events preceding the tsunami, reviews findings following the event and outlines plans relating to similar future expected tsunamis.

Den& Nottingham, P.E. Pres&M

2002-01-01

252

Tsunami diaries  

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Full Text Available Inspired by recent discussion on how Serbian media influenced allegedly indifferent reaction of the public to the aftermath of tsunami, this paper examines the role of electronic media in Serbia, television in particular, in regard to their function as a central communication channel for acquiring knowledge about world surroundings. With a premise of having cultural and discursive power, Dnevnik, the central news program of the Serbian public broadcaster, is taken as a paradigmatic media text for analysis in order to examine ways in which global affairs and phenomena are portrayed and structured in television representation of reality. It is suggested that it is fair to conclude that world affairs are marginalized within the representational frame of news broadcasts, and that the media discourse could be depicted as dominantly introverted when it comes to global flow of information and cultural meanings, which is significant regarding cultural perception of world realities among Serbian audiences.

Radovi? Sr?an

2005-01-01

253

Tsunami asymptotics  

International Nuclear Information System (INIS)

By applying the technique of uniform asymptotic approximation to the oscillatory integrals representing tsunami wave profiles, the form of the travelling wave far from the source is calculated for arbitrary initial disturbances. The approximations reproduce the entire profiles very accurately, from the front to the tail, and their numerical computation is much faster than that of the oscillatory integrals. For one-dimensional propagation, the uniform asymptotics involve Airy functions and their derivatives; for two-dimensional propagation, the uniform asymptotics involve products of these functions. Separate analyses are required when the initial disturbance is specified as surface elevation or surface velocity as functions of position, and when these functions are even or odd. 'There was an awful rainbow once in heaven' (John Keats, 1820)

2005-01-01

254

Les Houches Squared Event Generator for the NMSSM  

International Nuclear Information System (INIS)

We present a generic framework for event generation in the Next-to-Minimal Supersymmetric Standard Model (NMSSM), including the full chain of production process, resonance decays, parton showering, hadronization, and hadron decays. The framework at present uses NMHDECAY to compute the NMSSM spectrum and resonance widths, CALCHEP for the generation of hard scattering processes, and PYTHIA for resonance decays and fragmentation. The interface between the codes is organized by means of two Les Houches Accords, one for supersymmetric mass and coupling spectra (SLHA,2003) and the other for the event generator interface (2000)

2005-01-01

255

Les Houches Squared Event Generator for the NMSSM  

Energy Technology Data Exchange (ETDEWEB)

We present a generic framework for event generation in the Next-to-Minimal Supersymmetric Standard Model (NMSSM), including the full chain of production process, resonance decays, parton showering, hadronization, and hadron decays. The framework at present uses NMHDECAY to compute the NMSSM spectrum and resonance widths, CALCHEP for the generation of hard scattering processes, and PYTHIA for resonance decays and fragmentation. The interface between the codes is organized by means of two Les Houches Accords, one for supersymmetric mass and coupling spectra (SLHA,2003) and the other for the event generator interface (2000).

Pukhov, A.; /Moscow State U.; Skands, P.; /Fermilab

2005-12-01

256

Community destruction and traumatic stress in post-tsunami indonesia.  

UK PubMed Central (United Kingdom)

How are individuals affected when the communities they live in change for the worse? This question is central to understanding neighborhood effects, but few study designs generate estimates that can be interpreted causally. We address issues of inference through a natural experiment, examining post-traumatic stress at multiple time points in a population differentially exposed to the 2004 Indian Ocean tsunami. The data, from the Study of the Tsunami Aftermath and Recovery, include interviews with over 16,000 Indonesian adults before and after the event. These data are combined with satellite imagery, direct observation, and informant interviews to examine the consequences of community destruction for post-traumatic stress. Using multilevel linear mixed models, we show that community destruction worsens post-traumatic stress, net of rigorous controls for individual experiences of trauma and loss. Furthermore, the effect of community destruction persists over time and extends across a wide range of community types.

Frankenberg E; Nobles J; Sumantri C

2012-01-01

257

Plate Boundary Observatory Strain Recordings of the February 27, 2010, M8.8 Chile Tsunami  

Science.gov (United States)

In the hours that followed the February 27, 2010 M8.8 Chile earthquake a tsunami swept across the Pacific Ocean causing alerts to be issued from Antarctica to Alaska. PBO borehole strainmeters, at Ucluelet, Bamfield and Port Alberni, on Vancouver Island, Canada, recorded the arrival of the tsunami along the British Columbia coastline. In this presentation we describe the nature of the strain signal generated by the February 27, 2010 tsunami and compare it to seismic, GPS, pore-pressure, barometric pressure and tide gauge measurements made at or near the PBO borehole installations. The Ucluelet and Bamfield strainmeters, on the west coast of Vancouver Island, recorded the arriving waves ~ 16.5 hours after the M8.8 earthquake. The Port Alberni strainmeter, located on the northeast end of Alberni Inlet, a 1-2 km wide and 40 km long fjord recorded the first waves ~45 minutes later. The Ucluelet and Bamfield strainmeter arrival times are consistent with tide gauge measurements made at Tofino, 30 km north of Ucluelet. Areal strain amplitudes of up to 15 to 20 nanostrain were recorded at the three strainmeters and significant tsunami oscillations persisted for days. A PBO strainmeter 2.5 km from the Oregon coast did record a tsunami related signal though it was much smaller than at the three Vancouver Island sites. The Oregon site thus provides information on the attenuation of the signal with distance from the coastline. The ability of the strainmeters to record the tsunami signals following the 2010 M8.8 Chile and 2009 M8.1 Samoa events suggest they, or possibly less costly borehole tiltmeters, could be used as land-based instruments to record tsunami arrival times and provide estimates of wave heights.

Hodgkinson, Kathleen; Mencin, Dave; Borsa, Adrian; Jackson, Mike

2010-05-01

258

Measuring Tsunami Current Velocities on California’s North Coast  

Science.gov (United States)

The Northern California coast is particularly susceptible to tsunami damage. Thirty-one tsunamis have been recorded since 1933 when the first tide gauge was installed at Citizen’s Dock in Crescent City, California and four have caused damage. In November 2006, a magnitude 8.3 earthquake in the Kuril Islands generated a tsunami that caused over $20 million in damages and replacement costs to the Crescent City small boat basin. The 2006 tsunami did not flood any areas above the normal high tide; very strong currents produced as the tsunami surged in and out of the small boat basin caused all of the damage. The Harbor Master and commercial fishermen in the area estimated the peak currents near the mouth of the small boat basin at 12 to 15 knots or 6 to 8 m/sec. MOST numerical modeling of the 2006 currents in Crescent City gives peak velocities in the 2-3 m/sec range. We have initiated a pilot project to directly measure current velocities produced by moderate tsunamis such as the 2006 event. In spring of 2009 we acquired a Nortek Aquadopp 600 kHz acoustic 2-D current profiler through a donation from the Pacific Gas and Electric Company to measure currents in Humboldt Bay, located 100 km south of Crescent City. The manufacturer specifies the current meter can measure currents up to 10 m/sec. In a preliminary deployment at the Fairhaven dock inside Humboldt Bay in May 2009, we measured current velocities of 1.5 m/sec caused by the daily tidal fluctuation with a 1 minute sampling rate. Our primary goal is to model control and data telemetry of this current meter after NOAA’s tsunami-ready tide gages, in collaboration with NOAA personnel at PMEL and CO-OPS. We also intend to make available real-time current measurements online for the local maritime community. In this poster, we present preliminary results from the current meter and discuss deployment and telecommunication considerations. While some interference is present in the closest range bins, the system measures currents in the nearby navigational channel that compare favorably to NOAA tidal predictions at a nearby location. Once the deployment and telemetry issues have been resolved at the Humboldt Bay site, we will be deploying two additional instruments in Crescent City.

Crawford, G. B.; Dengler, L. A.; Montoya, J.

2009-12-01

259

THE INAPPROPRIATE TSUNAMI ICON  

Directory of Open Access Journals (Sweden)

Full Text Available The supposition that the Japanese printmaker Hokusai intended to represent a tsunami in his print of the “Great Wave at Kanagawa” is unfounded and the use of his “Great Wave” as a tsunami icon gives a false impression of the nature of tsunami waves.

DoakC. Cox

2001-01-01

260

Science of Tsunami Hazards ??????  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Science of Tsunami Hazards published to disseminate the results of applied and theoretical research on tsunamis and to increase knowledge about their hazards. Science of Tsunami Hazards is a unique, peer-reviewed journal which has been published continuously without interruption s...

 
 
 
 
261

Producing Hard Processes Regarding the Complete Event: The EPOS Event Generator  

CERN Document Server

Jet cross sections can be in principle compared to simple pQCD calculations, based on the hypothesis of factorization. But often it is useful or even necessary to not only compute the production rate of the very high pt jets, but in addition the "rest of the event". The proposed talk is based on recent work, where we try to construct an event generator fully compatible with pQCD which allows to compute complete events, consisting of high pt jets plus all the other low pt particles produced at the same time. Whereas in "generators of inclusive spectra" like Pythia one may easily trigger on high pt phenomena, this is not so obvious for "generators of physical events", where in principle one has to generate a very large number of events in order to finally obtain rare events (like those with a very high pt jet). We recently developped an independnat block method which allow us ta have a direct access to dedicated variables 1. We will present latest results concerning this approach.

Porteboeuf, S; Werner, K

2010-01-01

262

Overview of the BlockNormal Event Trigger Generator  

CERN Document Server

In the search for unmodeled gravitational wave bursts, there are a variety of methods that have been proposed to generate candidate events from time series data. Block Normal is a method of identifying candidate events by searching for places in the data stream where the characteristic statistics of the data change. These change-points divide the data into blocks in which the characteristics of the block are stationary. Blocks in which these characteristics are inconsistent with the long term characteristic statistics are marked as Event-Triggers which can then be investigated by a more computationally demanding multi-detector analysis.

McNabb, J W C; Finn, L S; Rotthoff, E; Stuver, A; Summerscales, T; Sutton, P; Tibbits, M; Thorne, K; Zaleski, K D

2004-01-01

263

General-purpose event generators for LHC physics  

International Nuclear Information System (INIS)

We review the physics basis, main features and use of general-purpose Monte Carlo event generators for the simulation of proton-proton collisions at the Large Hadron Collider. Topics included are: the generation of hard scattering matrix elements for processes of interest, at both leading and next-to-leading QCD perturbative order; their matching to approximate treatments of higher orders based on the showering approximation; the parton and dipole shower formulations; parton distribution functions for event generators; non-perturbative aspects such as soft QCD collisions, the underlying event and diffractive processes; the string and cluster models for hadron formation; the treatment of hadron and tau decays; the inclusion of QED radiation and beyond Standard Model processes. We describe the principal features of the ARIADNE, Herwig++, PYTHIA 8 and SHERPA generators, together with the Rivet and Professor validation and tuning tools, and discuss the physics philosophy behind the proper use of these generators and tools. This review is aimed at phenomenologists wishing to understand better how parton-level predictions are translated into hadron-level events as well as experimentalists seeking a deeper insight into the tools available for signal and background simulation at the LHC.

2011-01-01

264

The 2010 Chilean Tsunami Off the West Coast of Canada and the Northwest Coast of the United States  

Science.gov (United States)

The major ( M w = 8.8) Chilean earthquake of 27 February 2010 generated a trans-oceanic tsunami that was observed throughout the Pacific Ocean. Waves associated with this event had features similar to those of the 1960 tsunami generated in the same region by the Great ( M w = 9.5) 1960 Chilean Earthquake. Both tsunamis were clearly observed on the coast of British Columbia. The 1960 tsunami was measured by 17 analog pen-and-paper tide gauges, while the 2010 tsunami was measured by 11 modern digital coastal tide gauges, four NEPTUNE-Canada bottom pressure recorders located offshore from southern Vancouver Island, and two nearby open-ocean DART stations. The 2010 records were augmented by data from seven NOAA tide gauges on the coast of Washington State. This study examines the principal characteristics of the waves from the 2010 event (height, period, duration, and arrival and travel times) and compares these properties for the west coast of Canada with corresponding properties of the 1960 tsunami. Results show that the 2010 waves were approximately 3.5 times smaller than the 1960 waves and reached the British Columbia coast 1 h earlier. The maximum 2010 wave heights were observed at Port Alberni (98.4 cm) and Winter Harbour (68.3 cm); the observed periods ranged from 12 min at Port Hardy to 110-120 min at Prince Rupert and Port Alberni and 150 min at Bamfield. The open-ocean records had maximum wave heights of 6-11 cm and typical periods of 7 and 15 min. Coastal and open-ocean tsunami records revealed persistent oscillations that "rang" for 3-4 days. Tsunami energy occupied a broad band of periods from 3 to 300 min. Estimation of the inverse celerity vectors from cross-correlation analysis of the deep-sea tsunami records shows that the tsunami waves underwent refraction as they approached the coast of Vancouver Island with the direction of the incoming waves changing from an initial direction of 340° True to a direction of 15° True for the second train of waves that arrived 7 h later after possible reflection from the Marquesas and Hawaiian islands.

Rabinovich, Alexander B.; Thomson, Richard E.; Fine, Isaac V.

2013-09-01

265

THE SAMOA TSUNAMI OF 29 SEPTEMBER 2009 Early Warning and Inundation Assessment  

Directory of Open Access Journals (Sweden)

Full Text Available On 29 September 2009 at 17:48:11 UTC, a large earthquake of magnitude 8 struck off-shore of the Samoa Islands and generated a large tsunami that destroyed several villages and caused more than 160 fatalities. This report first presents the characteristics of the earthquake and discusses the best estimations for the fault parameters, which are the necessary input data for the hydrodynamic tsunami calculations. Then, the assessment of the near-real time systems invoked by the Global Disasters Alert and Coordination System (GDACS)1 and the post-event calculations are performed, making comparisons with the observed tidal measurements and post-event survey. It was found that the most severely damaged locations are the Southern section of the Western Samoa Islands, Tutuila Isl in American Samoa and Niuatoputapu Isle in Tonga. This is in agreement with the locations indicated by the Red Cross as the most affected and with the results of the post-tsunami surveys. Furthermore, an attempt was made to map the inundation events using more detailed digital elevation models (DEM) and hydrodynamic modelling with good results. The flooded areas for which we had satellite images and post-tsunami surveys confirm the inundated areas identified correctly by the hydrodynamic model. Indications are given on the DEM grid size needed for the different simulations.

Giovanni Franchello; Alessandro Annunziato

2012-01-01

266

Geomorphic Environments of Tsunami Deposits, Southeastern India  

Science.gov (United States)

As paleotsunami research progresses around the Indian Ocean, it is increasingly evident that tsunamis have occurred in this region in the past. The largest of these could have traversed the ocean and reached the southeastern coast of India, which highlights the importance of identifying key preservation sites in this potential repository of catastrophic basin-wide events. However, geologically enduring sites where tsunami deposits dependably survive are not yet well defined in India and other tropical environments. The purpose of this project was to identify the settings conducive to long-term preservation of tsunami deposits in tropical India and develop criteria for distinguishing them in the stratigraphic record. We documented the post- depositional fate of the tsunami deposits from the 2004 Sumatra-Andaman earthquake in various geomorphic environments along the southeastern coast of Tamil Nadu, India from 10.5-13° N. Latitude. Deposits from the 2004 tsunami were mapped, described and surveyed at locations where they had been described immediately after the event, as well as at previously unstudied sites. At many sites, the tsunami deposits were recognizable in the stratigraphic column by characteristic fine mafic laminations, debris and an organic layer at the lower boundary. Field observations and initial grain-size analysis indicated a distinct difference between tsunami deposits and underlying sedimentary layers. For example, at Mamallapuram (12.5° N. Lat.) the mean grain size of the tsunami deposits was 0.25 phi finer than that of the underlying layers. However, only three years after the event, deposits in some locations had already been altered significantly by erosion, bioturbation and incipient weathering and were not readily recognizable in the stratigraphy. Although the 2004 tsunami deposits were thicker and more extensive in the hard-hit southern half of the study area, the degree of bioturbation and weathering was greater there than in the drier northern portion, where some thin tsunami sand layers behind coastal dunes remained unaltered since the original post- tsunami surveys. To date, no conclusive evidence of paleotsunami deposits has been found at the sites included in this study, but the results will guide the search for key settings that best satisfy the balance between sediment volume and preservation.

Johnston, P.; Ely, L.; Achyuthan, H.; Srinivasalu, S.

2008-12-01

267

SAGE CALCULATIONS OF THE TSUNAMI THREAT FROM LA PALMA  

Directory of Open Access Journals (Sweden)

Full Text Available With the LANL multiphysics hydrocode SAGE, we have performed several two-dimensional calculations and one three-dimensional calculation using the full Navier-Stokes equations, of a hypothetical landslide resembling the event posited by Ward and Day (2001), a lateral flank collapse of the Cumbre Vieja Volcano on La Palma that would produce a tsunami. The SAGE code has previously been used to model the Lituya Bay landslide-generated tsunami (Mader & Gittings, 2002), and has also been used to examine tsunami generation by asteroid impacts (Gisler, Weaver, Mader, & Gittings, 2003). This code uses continuous adaptive mesh refinement to focus computing resources where they are needed most, and accurate equations of state for water, air, and rock. We find that while high-amplitude waves are produced that would be highly dangerous to nearby communities (in the Canary Islands, and the shores of Morocco, Spain, and Portugal), the wavelengths and periods of these waves are relatively short, and they will not propagate efficiently over long distances.

Galen Gisler; Robert Weaver; Michael L. Gittings

2006-01-01

268

MODELING OF THE 1755 LISBON TSUNAMI  

Directory of Open Access Journals (Sweden)

Full Text Available The generation and propagation of the November 1, 1755 Lisbon earthquake generated tsunami is of current interest to the IOCARIBE Tsunami Scientific Steering Committee.The November 1, 1755 Lisbon earthquake generated a tsunami with a period of one hour and amplitudes of 20 meters at Lisbon and along the African and south European coasts, of 4 meters along the English coast, and of 7 meters at Saba in the Caribbean after 7 hours of travel. The modeling was performed using the SWAN code which solves the nonlinear long wave equations. The tsunami generation, and propagation was modeled using a 10. minute Mercator grid of 600 by 640 cells. The observed tsunami wavecharacteristics were approximatelyreproduced usinga source 300 kilometer in radius with a drop of 30 meters located in the region of the 1969 earthquake near the Gorringe bank. The east coast of the U.S.A. and the Caribbean received a tsunami wave off shore in deep water about 2 meters high with periods of 1.25 to 1.5 hours. The maximum wave amplitude after run-up would be about 10 feet. The Gulf of Mexico would have a wave with less than half that amplitude.

Charles L. Mader

2001-01-01

269

Absolute GPS Time Event Generation and Capture for Remote Locations  

Science.gov (United States)

The HiRes experiment operates fixed location and portable lasers at remote desert locations to generate calibration events. One physics goal of HiRes is to search for unusual showers. These may appear similar to upward or horizontally pointing laser tracks used for atmospheric calibration. It is therefore necessary to remove all of these calibration events from the HiRes detector data stream in a physics blind manner. A robust and convenient "tagging" method is to generate the calibration events at precisely known times. To facilitate this tagging method we have developed the GPSY (Global Positioning System YAG) module. It uses a GPS receiver, an embedded processor and additional timing logic to generate laser triggers at arbitrary programmed times and frequencies with better than 100nS accuracy. The GPSY module has two trigger outputs (one microsecond resolution) to trigger the laser flash-lamp and Q-switch and one event capture input (25nS resolution). The GPSY module can be programmed either by a front panel menu based interface or by a host computer via an RS232 serial interface. The latter also allows for computer logging of generated and captured event times. Details of the design and the implementation of these devices will be presented. 1 Motivation Air Showers represent a small fraction, much less than a percent, of the total High Resolution Fly's Eye data sample. The bulk of the sample is calibration data. Most of this calibration data is generated by two types of systems that use lasers. One type sends light directly to the detectors via optical fibers to monitor detector gains (Girard 2001). The other sends a beam of light into the sky and the scattered light that reaches the detectors is used to monitor atmospheric effects (Wiencke 1998). It is important that these calibration events be cleanly separated from the rest of the sample both to provide a complete set of monitoring information, and more

HIRES Collaboration

270

Holocene tsunamigenic sediments and tsunami modelling in the Thermaikos Gulf area (northern Greece)  

Science.gov (United States)

Shallow drill cores in flat and southerly exposed coastal areas around the Thermaikos Gulf (Thessalonica, northern Greece) provided evidence for past high energy sedimentary events, which are interpreted as tsunamites. A tsunamigenic source is located along the western tip of the North Anatolian Fault Zone (NAFZ) in the North Aegean Basin, where water depths ranging between 1.200 and 1.650 m are sufficiently deep to generate tsunamis. However, the event layers up to now cannot be assigned to individual seismic or landslide sources, but the potential of a tsunami threat in the Thermaikos Gulf area can now be tested, following both sedimentological and modelling processes. Such potential threat regarding the Thermaikos Gulf has only recently been notified but never tested and studied in depth. As a result, several Holocene coarse clastic layers have been found intercalated in clayey or gypsiferous lagoonal deposits. These layers have erosive bases, show fining-up and thinning-up sequences, and include shell debris, foraminifera and rip-up clasts of lagoonal sediments. A widely observed significant feature of these layers involves mud-coated beach clasts, clasts that rework the high-plasticity clays of lagoons. Such features that indicate highly disturbed sedimentological condition (hyperpyncal flows) are rarely described elsewhere. Multiple intercalations of these layers with all the mentioned indicative features downhole are interpreted paleotsunami deposits from tsunamis generated by earthquakes or earthquake-triggered submarine landslides triggered by seismic shaking in the Thermaikos Gulf. Modelling of the tsunami potential of the basin-bounding fault southwards of the Thermaikos Gulf provides an example for possible tsunami generation at only one segment of NAFZ along an approx. 55 km normal fault at the southern fault-bound margin of the North Aegean Basin. The Herodotus Histories report on inundations and sea withdrawals occurring during the Greek-Persian war, which occurred near Potidea. In the ancient Greek village Mende we found evidence for a tsunamigenic layer, dated with shells to 2500 BP, which may tentatively be interpreted as the sedimentary remains of the "Herodotus tsunami" in 479 BC. Acknowledgements: This work has been supported financially by the DAAD-IKYDA Project (Tracing tsunami deposits in the Thermaikos Gulf, Northern Greece. Implications for seismic and tsunami hazard and archaeology) and the RWTH Aachen University.

Reicherter, Klaus; Papanikolaou, Ioannis D.; Roger, Jean; Grützner, Christoph; Stamatis, Georgios; Papanikolaou, Dimitrios

2010-05-01

271

Earthquake related tsunami hazard along the western coast of Thailand  

Directory of Open Access Journals (Sweden)

Full Text Available The primary background for the present study was a project to assist the authorities in Thailand with development of plans for how to deal with the future tsunami risk in both short and long term perspectives, in the wake of the devastating 26 December 2004 Sumatra-Andaman earthquake and tsunami. The study is focussed on defining and analyzing a number of possible future earthquake scenarios (magnitudes 8.5, 8.0 and 7.5) with associated return periods, each one accompanied by specific tsunami modelling. Along the most affected part of the western coast of Thailand, the 2004 tsunami wave caused a maximum water level ranging from 5 to 15 m above mean sea level. These levels and their spatial distributions have been confirmed by detailed numerical simulations. The applied earthquake source is developed based on available seismological and geodetic inversions, and the simulation using the source as initial condition agree well with sea level records and run-up observations. A conclusion from the study is that another megathrust earthquake generating a tsunami affecting the coastline of western Thailand is not likely to occur again for several hundred years. This is in part based on the assumption that the Southern Andaman Microplate Boundary near the Simeulue Islands constitutes a geologic barrier that will prohibit significant rupture across it, and in part on the decreasing subduction rates north of the Banda Ache region. It is also concluded that the largest credible earthquake to be prepared for along the part of the Sunda-Andaman arc that could affect Thailand, is within the next 50–100 years an earthquake of magnitude 8.5, which is expected to occur with more spatial and temporal irregularity than the megathrust events. Numerical simulations have shown such earthquakes to cause tsunamis with maximum water levels up to 1.5–2.0 m along the western coast of Thailand, possibly 2.5–3.0 m on a high tide. However, in a longer time perspective (say more than 50–100 years) the potentials for earthquakes of similar magnitude and consequences as the 2004 event will become gradually larger and eventually posing an unacceptable societal risk. These conclusions apply only to Thailand, since the effects of an M 8.5 earthquake in the same region could be worse for north-western Sumatra, the Andaman and Nicobar Islands, maybe even for Sri Lanka and parts of the Indian coastline. Moreover, further south along the Sunda arc the potentials for large ruptures are now much higher than for the region that ruptured on 26 December 2004.

F. Løvholt; H. Bungum; C. B. Harbitz; S. Glimsdal; C. D. Lindholm; G. Pedersen

2006-01-01

272

Event tree analysis for steam generator tube ruptures  

International Nuclear Information System (INIS)

The probabilistic safety analysis on steam generator tube ruptures in nuclear power plants is presented. The reactor core melt frequencies 1.26 x 10-6/a reactor resulted from 1 to 2 steam generator tube ruptures during power operation are shown, and the dominant accident sequences are also given. The importance of simulation training on timely operators' interventions in the event is stressed

1999-01-01

273

Twin Tsunamis Triggered by the 12 January 2010 Haiti Earthquake  

Science.gov (United States)

On 12 January 2010, a magnitude M w 7.0 earthquake occurred 25 km west-southwest of Haiti's capital Port-au-Prince causing an estimated 316,000 fatalities, thereby exceeding any previous loss of life from a similar size earthquake. In addition, tsunami waves triggered by the earthquake caused at least three fatalities at Petit Paradis due to a complete lack of tsunami awareness. The International Tsunami Survey Team (ITST) was deployed within weeks of the event and covered the greater Bay of Port-au-Prince and more than 100 km of Hispaniola's southern coastline. The collected survey data include more than 21 tsunami heights along with observations of coastal land level change. Maximum tsunami heights of 3 m have been measured for two independently triggered tsunamis.

Fritz, Hermann M.; Hillaire, Jean Vilmond; Molière, Emanuel; Wei, Yong; Mohammed, Fahad

2013-09-01

274

Towards a certification process for tsunami early warning systems  

Science.gov (United States)

The natural disaster of the Boxing Day Tsunami of 2004 was followed by an information catastrophe. Crucial early warning information could not be delivered to the communities under imminent threat, resulting in over 240,000 casualties in 14 countries. This tragedy sparked the development of a new generation of integrated modular Tsunami Early Warning Systems (TEWS). While significant advances were accomplished in the past years, recent events, like the Chile 2010 and the Tohoku 2011 tsunami demonstrate that the key technical challenge for Tsunami Early Warning research on the supranational scale still lies in the timely issuing of status information and reliable early warning messages in a proven workflow. A second challenge stems from the main objective of the Intergovernmental Oceanographic Commission of UNESCO (IOC) Tsunami Programme, the integration of national TEWS towards ocean-wide networks: Each of the increasing number of integrated Tsunami Early Warning Centres has to cope with the continuing evolution of sensors, hardware and software while having to maintain reliable inter-center information exchange services. To avoid future information catastrophes, the performance of all components, ranging from individual sensors, to Warning Centers within their particular end-to-end Warning System Environments, and up to federated Systems of Tsunami Warning Systems has to be regularly validated against defined criteria. Since 2004, GFZ German Research Centre for Geosciences (GFZ) has built up expertise in the field of TEWS. Within GFZ, the Centre for GeoInformation Technology (CeGIT) has focused its work on the geoinformatics aspects of TEWS in two projects already, being the German Indonesian Tsunami Early Warning System (GITEWS) and the Distant Early Warning System (DEWS). This activity is continued in the TRIDEC project (Collaborative, Complex, and Critical Decision Processes in Evolving Crises) funded under the European Union's seventh Framework Programme (FP7). TRIDEC focuses on real-time intelligent information management in Earth management and its long-term application: The technical development is based on mature system architecture models and industry standards. The use of standards already applies to the operation of individual TRIDEC reference installations and their interlinking into an integrated service infrastructure for supranational warning services. This is a first step towards best practices and service lifecycles for Early Warning Centre IT service management, including Service Level Agreements (SLA) and Service Certification. While on a global scale the integration of TEWS progresses towards Systems of Systems (SoS), there is still an absence of accredited and reliable certifications for national TEWS or regional Tsunami Early Warning Systems of Systems (TEWSoS). Concepts for TEWS operations have already been published under the guidance of the IOC, and can now be complemented by the recent research advances concerning SoS architecture. Combined with feedback from the real world, such as the NEAMwave 2012 Tsunami exercise in the Mediterranean, this can serve as a starting point to formulate initial requirements for TEWS and TEWSoS certification: Certification activities will cover the establishment of new TEWS and TEWSoS, and also both maintenance and enhancement of existing TEWS/TEWSoS. While the IOC is expected to take a central role in the development of the certification strategy, it remains to be defined which bodies will actually conduct the certification process. Certification requirements and results are likely to become a valuable information source for various target groups, ranging from national policy decision makers, government agency planners, national and local government preparedness officials, TWC staff members, Disaster Responders, the media and the insurance industry.

Löwe, Peter; Wächter, Jochen; Hammitzsch, Martin

2013-04-01

275

DID A SUBMARINE SLIDE TRIGGER THE 1918 PUERTO RICO TSUNAMI?  

Directory of Open Access Journals (Sweden)

Full Text Available The 1918 tsunami that inundated northwest Puerto Rico with up to 6 m waves has been attributed to seafloor faulting associated with the 1918 Mona Canyon earthquake. During the earthquake a series of submarine cable breaks occurred directly off the northwest coast of Puerto Rico where the largest tsunami waves came ashore. Here, we use a recently compiled geophysical data set to reveal that a 9 km long landslide headwall exists in the region where cable breaks occurred during the 1918 earthquake. We incorporate our interpretations into a near-field tsunami wave model to evaluate whether the slide may have triggered the observed 1918 tsunami. Our analysis indicates that this slide could generate a tsunami with phase, arrival times, and run-ups similar to observations along the northwest coast of Puerto Rico. We therefore suggest that a submarine slide offers a plausible alternative explanation for generation of this large tsunami.

Matthew J. Hornbach; Steven A. Mondzie; Nancy R. Grindlay; Cliff Frohlich; Paul Mann

2008-01-01

276

Sensor-generated time series events: a definition language.  

UK PubMed Central (United Kingdom)

There are now a great many domains where information is recorded by sensors over a limited time period or on a permanent basis. This data flow leads to sequences of data known as time series. In many domains, like seismography or medicine, time series analysis focuses on particular regions of interest, known as events, whereas the remainder of the time series contains hardly any useful information. In these domains, there is a need for mechanisms to identify and locate such events. In this paper, we propose an events definition language that is general enough to be used to easily and naturally define events in time series recorded by sensors in any domain. The proposed language has been applied to the definition of time series events generated within the branch of medicine dealing with balance-related functions in human beings. A device, called posturograph, is used to study balance-related functions. The platform has four sensors that record the pressure intensity being exerted on the platform, generating four interrelated time series. As opposed to the existing ad hoc proposals, the results confirm that the proposed language is valid, that is generally applicable and accurate, for identifying the events contained in the time series.

Anguera A; Lara JA; Lizcano D; Martínez MA; Pazos J

2012-01-01

277

Sensor-Generated Time Series Events: A Definition Language  

Directory of Open Access Journals (Sweden)

Full Text Available There are now a great many domains where information is recorded by sensors over a limited time period or on a permanent basis. This data flow leads to sequences of data known as time series. In many domains, like seismography or medicine, time series analysis focuses on particular regions of interest, known as events, whereas the remainder of the time series contains hardly any useful information. In these domains, there is a need for mechanisms to identify and locate such events. In this paper, we propose an events definition language that is general enough to be used to easily and naturally define events in time series recorded by sensors in any domain. The proposed language has been applied to the definition of time series events generated within the branch of medicine dealing with balance-related functions in human beings. A device, called posturograph, is used to study balance-related functions. The platform has four sensors that record the pressure intensity being exerted on the platform, generating four interrelated time series. As opposed to the existing ad hoc proposals, the results confirm that the proposed language is valid, that is generally applicable and accurate, for identifying the events contained in the time series.

Aurea Anguera; Juan A. Lara; David Lizcano; Maria Aurora Martínez; Juan Pazos

2012-01-01

278

UNDERSTANDING TSUNAMI RISK TO STRUCTURES: A CANADIAN PERSPECTIVE  

Directory of Open Access Journals (Sweden)

Full Text Available The potential catastrophic effects of tsunami-induced loading on built infrastructure in the vicinity of shorelines have been brought to the fore by recent global events. However, state- of-the-art building codes remain silent or provide conflicting guidance on designing near- shoreline structures in tsunami-prone areas. This paper focuses on tsunami-induced loading and its effect on structures within the Canadian context. The mechanics of tsunami-induced loading is described based on knowledge gained during reconnaissance visits after the 2004 south-east Asia Tsunami, as well as post-construction visits to countries significantly affected by the destructive forces of the tsunami. To gain an appreciation of the magnitude of tsunami-induced bores for a given seismic event along the western coastal region of Canada, structural analysis of a simple near-shoreline structure was performed considering a proposed loading protocol for tsunami-induced hydraulic bores. These loads were further compared to seismic loading in order to provide an estimation of the tsunami risk and its impact. The work was complemented by experimental results from a large-scale testing program conducted with the purpose of estimating the forces experienced on structural components. Square-, rectangular-, and diamond-shaped columns were used to study the influence of shape. Furthermore, results from debris impact testing are also discussed.

D. Palermo; I. Nistor

2008-01-01

279

NLO event generation for chargino production at the ILC  

International Nuclear Information System (INIS)

[en] We present a Monte-Carlo event generator for simulating chargino pair-production at the International Linear Collider (ILC) at next-to-leading order in the electroweak couplings. By properly resumming photons in the soft and collinear regions, we avoid negative event weights, so the program can simulate physical (unweighted) event samples. Photons are explicitly generated throughout the range where they can be experimentally resolved. Inspecting the dependence on the cutoffs separating the soft and collinear regions, we evaluate the systematic errors due to soft and collinear approximations. In the resummation approach, the residual uncertainty can be brought down to the per-mil level, coinciding with the expected statistical uncertainty at the ILC. (Orig.)

2006-01-01

280

DJANGO: the interface for the event generators HERACLES and LEPTO  

International Nuclear Information System (INIS)

The Monte Carlo event generator HERACLES has been extended to include QCD effects. Multiple gluon radiation is incorporated in a parton shower approach assuming factorization of higher order QED and QCD corrections. The LUND-string fragmentation is used to obtain the complete hadronic final state. (orig.).

1992-01-01

 
 
 
 
281

EDDE Monte Carlo event generator.Version 2.1  

CERN Document Server

EDDE is a Monte Carlo event generator for different Exclusive and Semi-Inclusive Double Diffractive processes. The program is based on the extended Regge-eikonal approach for "soft" processes. Standard Model and its extensions are used for "hard" fusion processes. An interface to PYTHIA and CMSSW is provided.

Petrov, V A; Sobol, A E; Guillaud, J -P

2007-01-01

282

Art Therapy with Child Tsunami Survivors in Sri Lanka  

Science.gov (United States)

|This paper details art therapy with children affected by the December 2004 tsunami in Sri Lanka. Over 30,000 Sri Lankans lost their lives when the tsunami decimated coastal areas. The child survivors witnessed horrific traumatic events and the loss of loved ones, but had not been given opportunity to express their grief and pain. A 4-week art…

Chilcote, Rebekah L.

2007-01-01

283

EVENT GENERATOR FOR RHIC SPIN PHYSICS-VOLUME 11  

Energy Technology Data Exchange (ETDEWEB)

This volume contains the report of the RIKEN BNL Research Center workshop on ''Event Generator for RHIC Spin Physics'' held on September 21-23, 1998 at Brookhaven National Laboratory. A major objective of the workshop was to establish a firm collaboration to develop suitable event generators for the spin physics program at RHIC. With the completion of the Relativistic Heavy Ion Collider (RHIC) as a polarized collider a completely new domain of high-energy spin physics will be opened. The planned studies address the spin structure of the nucleon, tests of the standard model, and transverse spin effects in initial and final states. RHIC offers the unique opportunity to pursue these studies because of its high and variable energy, 50 {le} {radical}s {le} 500 GeV, high polarization, 70%, and high luminosity, 2 x 10{sup 32} cm{sup -2} sec{sup -1} or more at 500 GeV. To maximize the output from the spin program at RHIC, the understanding of both experimental and theoretical systematic errors is crucial. It will require full-fledged event generators, to simulate the processes of interest in great detail. The history of event generators shows that their development and improvement are ongoing processes taking place in parallel to the physics analysis by various experimental groups. The number of processes included in the generators has been increasing and the precision of their predictions has been being improved continuously. Our workshop aims at getting this process well under way for the spin physics program at RHIC, based on the fist development in this direction, SPHINX. The scope of the work includes: (1) update of the currently existing event generator by including the most recent parton parameterizations as a library and reflecting recent progress made for spin-independent generators, (2) implementation of new processes, especially parity violating effects in high energy pp collisions, (3) test of the currently available event generator by comparing to existing experimental data and analytical calculations for the unpolarized case, and (4) search for ways to improve the treatment of polarization for the fragmentation phase.

SAITO,N.; SCHAEFER,A.

1998-12-01

284

Matrix elements and Parton Shower in the event generator BABAYAGA  

Science.gov (United States)

A new version of the event generator BABAYAGA is presented, which is based on an original matching of the Parton Shower approach with the complete exact O(?) matrix element for the inclusion of the QED radiative corrections to the Bhabha process at flavour factories. The theoretical accuracy of the improved generator is conservatively estimated to be 0.2%, by comparison with independent calculations. The generator is a useful tool for precise luminosity determination at flavour factories, for center-of-mass energies below 10 GeV.

Balossini, G.; Carloni Calame, C. M.; Montagna, G.; Nicrosini, O.; Piccinini, F.

2006-12-01

285

Exclusive event generator for $e^+e^-$ scan experiments  

CERN Multimedia

An exclusive event generator is designed for the $e^+e^-$ scan experiments with the initial state radiation effects up to the second order correction included. There are seventy hadronic decay modes available with the effective center-of-mass energy coverage from the two pion mass threshold up to about 6 GeV. The achieved accuracy of initial state radiation correction reaches the level the generator KKMC achieved. The uncertainty associated with the calculation of correction factor to the initial state radiation is dominated by the measurements of the energy-dependence Born cross section. The generator is coded within the framework of BesEvtGen.

Ping, Rong-Gang

2013-01-01

286

Development of a Dynamic Event Tree for a Pressurized Water Reactor Steam Generator Tube Rupture Event  

International Nuclear Information System (INIS)

The DPRA-SGTR computer program was written to develop a dynamic event tree for the analysis of a steam generator (SG) tube rupture (SGTR) event. Using the dynamic event tree, a full-scope understanding of the possible responses of a plant following an SGTR event and the related actions with the emergency operating procedures (EOPs) can be analyzed. RELAP5/MOD3.2 was linked to DPRA-SGTR to calculate the thermal-hydraulic response of a Westinghouse three-loop pressurized water reactor at the Maanshan nuclear power plant. One SG tube with a double-ended break was postulated at the beginning of the accident. The plant thermal-hydraulic behaviors, status of the mitigation systems, and operator actions following the EOPs were explicitly modeled in the postulated SGTR. A total of 131 sequences were generated after an SGTR event. Among the 131 sequences, 91 sequences with a frequency sum of 8.5 x 10-6 were stopped either because of low-occurrence frequency (-12) or because the preset mission time was reached (30 000 s after initiating the event). Seven out of the 91 sequences with a frequency sum of 6 x 10-9 were intentionally stopped as a fatal error occurred when RELAP5 was calculating the thermal-hydraulic response

2000-01-01

287

TIDE-TSUNAMI INTERACTIONS  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper we investigate important dynamics defining tsunami enhancement in the coastal regions and related to interaction with tides. Observations and computations of the Indian Ocean Tsunami usually show amplifications of the tsunami in the near-shore regions due to water shoaling. Additionally, numerous observations depicted quite long ringing of tsunami oscillations in the coastal regions, suggesting either local resonance or the local trapping of the tsunami energy. In the real ocean, the short-period tsunami wave rides on the longer-period tides. The question is whether these two waves can be superposed linearly for the purpose of determining the resulting sea surface height (SSH) or rather in the shallow water they interact nonlinearly, enhancing/reducing the total sea level and currents. Since the near–shore bathymetry is important for the run-up computation, Weisz and Winter (2005) demonstrated that the changes of depth caused by tides should not be neglected in tsunami run-up considerations. On the other hand, we hypothesize that much more significant effect of the tsunami-tide interaction should be observed through the tidal and tsunami currents. In order to test this hypothesis we apply a simple set of 1-D equations of motion and continuity to demonstrate the dynamics of tsunami and tide interaction in the vicinity of the shelf break for two coastal domains: shallow waters of an elongated inlet and narrow shelf typical for deep waters of the Gulf of Alaska.

Zygmunt Kowalik; Tatiana Proshutinsky; Andrey Proshutinsky

2006-01-01

288

Heavy ion event generator HYDJET++ (HYDrodynamics plus JETs)  

CERN Document Server

HYDJET++ is a Monte-Carlo event generator for the simulation of relativistic heavy ion AA collisions considered as a superposition of the soft, hydro-type state and the hard, multi-parton state. This model is the development and continuation of HYDJET event generator (Lokhtin & Snigirev, 2006, EPJC, 45, 211). The main program is written in the object-oriented C++ language under the ROOT environment. The hard part of HYDJET++ is identical to the hard part of Fortran-written HYDJET and is included in the generator structure as a separate directory. The soft part of HYDJET++ event is the "thermal" hadronic state generated on the chemical and thermal freeze-out hypersurfaces represented by the parameterization of relativistic hydrodynamics with preset freeze-out conditions. It includes longitudinal, radial and elliptic flow effects and decays of hadronic resonances. The corresponding fast Monte-Carlo simulation procedure, C++ code FAST MC (Amelin et al., 2006, PRC, 74, 064901; 2008, PRC, 77, 014903) is adapte...

Lokhtin, I P; Petrushanko, S V; Snigirev, A M; Arsene, I; Tywoniuk, K

2008-01-01

289

Tsunami Modeling to Validate Slip Models of the 2007 M w 8.0 Pisco Earthquake, Central Peru  

Science.gov (United States)

Following the 2007, August 15th, M w 8.0, Pisco earthquake in central Peru, Sladen et al. (J Geophys Res 115: B02405, 2010) have derived several slip models of this event. They inverted teleseismic data together with geodetic (InSAR) measurements to look for the co-seismic slip distribution on the fault plane, considering those data sets separately or jointly. But how close to the real slip distribution are those inverted slip models? To answer this crucial question, the authors generated some tsunami records based on their slip models and compared them to DART buoys, tsunami records, and available runup data. Such an approach requires a robust and accurate tsunami model (non-linear, dispersive, accurate bathymetry and topography, etc.) otherwise the differences between the data and the model may be attributed to the slip models themselves, though they arise from an incomplete tsunami simulation. The accuracy of a numerical tsunami simulation strongly depends, among others, on two important constraints: (i) A fine computational grid (and thus the bathymetry and topography data sets used) which is not always available, unfortunately, and (ii) a realistic tsunami propagation model including dispersion. Here, we extend Sladen's work using newly available data, namely a tide gauge record at Callao (Lima harbor) and the Chilean DART buoy record, while considering a complete set of runup data along with a more realistic tsunami numerical that accounts for dispersion, and also considering a fine-resolution computational grid, which is essential. Through these accurate numerical simulations we infer that the InSAR-based model is in better agreement with the tsunami data, studying the case of the Pisco earthquake indicating that geodetic data seems essential to recover the final co-seismic slip distribution on the rupture plane. Slip models based on teleseismic data are unable to describe the observed tsunami, suggesting that a significant amount of co-seismic slip may have been aseismic. Finally, we compute the runup distribution along the central part of the Peruvian coast to better understand the wave amplification/attenuation processes of the tsunami generated by the Pisco earthquake.

Ioualalen, M.; Perfettini, H.; Condo, S. Yauri; Jimenez, C.; Tavera, H.

2013-03-01

290

Observing sea level and current anomalies driven by a megathrust slope-shelf tsunami: The event on February 27, 2010 in central Chile  

Science.gov (United States)

At 03:34 (local time) on 27 February 2010, the world's sixth largest earthquake on record (8.8 Mw) occurred off central Chile, rupturing a segment about 550 km long of the Nazca-South America plate boundary fault parallel to the coastline. This earthquake triggered a destructive tsunami that affected the entire Pacific basin, especially the Chilean coast in an extension of ˜580 km. Here we analyze observations of currents and sea level anomalies caused by the tsunami that were recorded ˜30 km east of the epicenter by an RDI 600 kHz ADCP installed facing upward at 35 m depth. Although the ADCP sampling rate was not optimal for this kind of phenomenon, we were able to document for the first time near-field ocean hydrodynamics caused by an earthquake-triggered tsunami. We combine our observations with measurements of sea level recorded by tide gauges located along the Chilean coast.The ADCP recorded the passage of five waves of about 1.5-2 m amplitude during approximately 4 h after the earthquake. The first wave hit the coast in about 20 min with slow flows and propagated faster northwards (where the trench is deeper) than it did to the south. The first strong flow arrived cross-shore (after the first wave) with a vertical mean speed of 65 cm/s. Unlike this first cross-shore flow, the following peak flows were increasingly aligned with the coastline and had magnitudes that, in at least two cases, exceeded 70 cm/s. These flows were consistent with edge waves driven by the contact between the tsunami and the coastline. Current and sea level measurements had more energetic periods at 35, 50 and 72 min, displaying a coherent relationship with the dominant oscillation modes of large-scale resonance.

Sobarzo, Marcus; Garcés-Vargas, José; Bravo, Luis; Tassara, Andrés; Quiñones, Renato A.

2012-10-01

291

2006: STATUS OF TSUNAMI SCIENCE RESEARCH AND FUTURE DIRECTIONS OF RESEARCH  

Directory of Open Access Journals (Sweden)

Full Text Available In 2005, Dr. Robert Wiegel compiled “Tsunami Information Sources”. The compilation has been made available via a website and has been published as an issue in Science of Tsunami Hazards. The compiled references have been assigned keyword descriptions, and compiled in order to review the breath and depth of Tsunami Science publications.The review indicates that tsunami research involves eight major scientific disciplines: Geology, Seismology, Tsunami Science, Engineering, Disaster Management, Meteorology and Communications. These disciplines were subdivided into many topical subjects and the results were tabulated.The topics having the largest number of publications include: tsunamigenic earthquakes, numerical modeling, field surveys, engineering models, harbor, bay, and canal modeling and observations, energy of tsunamis, workshops, tsunami warning centers, instrumentation, tsunami catalogs, tsunami disaster mitigation, evaluation of hazards, the aftermath of tsunamis on humans, and AID provided to Tsunami Damaged Communities.Several areas of research were identified as likely directions for future research, including: paleotsunami studies, risk assessments, instrumentation, numerical modeling of earthquakes and tsunami, particularly the 2004 Indian Ocean event. There is a dearth of recent publications available on tsunami hazards education for the general public.

Barbara H. Keating

2006-01-01

292

Toward tsunami early warning system in Indonesia by using rapid rupture durations estimation  

International Nuclear Information System (INIS)

[en] Indonesia has Indonesian Tsunami Early Warning System (Ina-TEWS) since 2008. The Ina-TEWS has used automatic processing on hypocenter; Mwp, Mw (mB) and Mj. If earthquake occurred in Ocean, depth 7, then Ina-TEWS announce early warning that the earthquake can generate tsunami. However, the announcement of the Ina-TEWS is still not accuracy. Purposes of this research are to estimate earthquake rupture duration of large Indonesia earthquakes that occurred in Indian Ocean, Java, Timor sea, Banda sea, Arafura sea and Pasific ocean. We analyzed at least 330 vertical seismogram recorded by IRIS-DMC network using a direct procedure for rapid assessment of earthquake tsunami potential using simple measures on P-wave vertical seismograms on the velocity records, and the likelihood that the high-frequency, apparent rupture duration, Tdur. Tdur can be related to the critical parameters rupture length (L), depth (z), and shear modulus (?) while Tdur may be related to wide (W), slip (D), z or ?. Our analysis shows that the rupture duration has a stronger influence to generate tsunami than Mw and depth. The rupture duration gives more information on tsunami impact, Mo/?, depth and size than Mw and other currently used discriminants. We show more information which known from the rupture durations. The longer rupture duration, the shallower source of the earthquake. For rupture duration greater than 50 s, the depth less than 50 km, Mw greater than 7, the longer rupture length, because Tdur is proportional L and greater Mo/?. Because Mo/? is proportional L. So, with rupture duration information can be known information of the four parameters. We also suggest that tsunami potential is not directly related to the faulting type of source and for events that have rupture duration greater than 50 s, the earthquakes generated tsunami. With available real-time seismogram data, rapid calculation, rupture duration discriminant can be completed within 4–5 min after an earthquake occurs and thus can aid in effective, accuracy and reliable tsunami early warning for Indonesia region.

2012-06-20

293

Toward tsunami early warning system in Indonesia by using rapid rupture durations estimation  

Energy Technology Data Exchange (ETDEWEB)

Indonesia has Indonesian Tsunami Early Warning System (Ina-TEWS) since 2008. The Ina-TEWS has used automatic processing on hypocenter; Mwp, Mw (mB) and Mj. If earthquake occurred in Ocean, depth < 70 km and magnitude > 7, then Ina-TEWS announce early warning that the earthquake can generate tsunami. However, the announcement of the Ina-TEWS is still not accuracy. Purposes of this research are to estimate earthquake rupture duration of large Indonesia earthquakes that occurred in Indian Ocean, Java, Timor sea, Banda sea, Arafura sea and Pasific ocean. We analyzed at least 330 vertical seismogram recorded by IRIS-DMC network using a direct procedure for rapid assessment of earthquake tsunami potential using simple measures on P-wave vertical seismograms on the velocity records, and the likelihood that the high-frequency, apparent rupture duration, T{sub dur}. T{sub dur} can be related to the critical parameters rupture length (L), depth (z), and shear modulus ({mu}) while T{sub dur} may be related to wide (W), slip (D), z or {mu}. Our analysis shows that the rupture duration has a stronger influence to generate tsunami than Mw and depth. The rupture duration gives more information on tsunami impact, Mo/{mu}, depth and size than Mw and other currently used discriminants. We show more information which known from the rupture durations. The longer rupture duration, the shallower source of the earthquake. For rupture duration greater than 50 s, the depth less than 50 km, Mw greater than 7, the longer rupture length, because T{sub dur} is proportional L and greater Mo/{mu}. Because Mo/{mu} is proportional L. So, with rupture duration information can be known information of the four parameters. We also suggest that tsunami potential is not directly related to the faulting type of source and for events that have rupture duration greater than 50 s, the earthquakes generated tsunami. With available real-time seismogram data, rapid calculation, rupture duration discriminant can be completed within 4-5 min after an earthquake occurs and thus can aid in effective, accuracy and reliable tsunami early warning for Indonesia region.

Madlazim [Physics Department, Faculty Mathematics and Sciences of Surabaya State University (UNESA) Jl. Ketintang, Surabaya 60231 (Indonesia)

2012-06-20

294

Complex earthquake rupture and local tsunamis  

Science.gov (United States)

In contrast to far-field tsunami amplitudes that are fairly well predicted by the seismic moment of subduction zone earthquakes, there exists significant variation in the scaling of local tsunami amplitude with respect to seismic moment. From a global catalog of tsunami runup observations this variability is greatest for the most frequently occuring tsunamigenic subduction zone earthquakes in the magnitude range of 7 < Mw < 8.5. Variability in local tsunami runup scaling can be ascribed to tsunami source parameters that are independent of seismic moment: variations in the water depth in the source region, the combination of higher slip and lower shear modulus at shallow depth, and rupture complexity in the form of heterogeneous slip distribution patterns. The focus of this study is on the effect that rupture complexity has on the local tsunami wave field. A wide range of slip distribution patterns are generated using a stochastic, self-affine source model that is consistent with the falloff of far-field seismic displacement spectra at high frequencies. The synthetic slip distributions generated by the stochastic source model are discretized and the vertical displacement fields from point source elastic dislocation expressions are superimposed to compute the coseismic vertical displacement field. For shallow subduction zone earthquakes it is demonstrated that self-affine irregularities of the slip distribution result in significant variations in local tsunami amplitude. The effects of rupture complexity are less pronounced for earthquakes at greater depth or along faults with steep dip angles. For a test region along the Pacific coast of central Mexico, peak nearshore tsunami amplitude is calculated for a large number (N = 100) of synthetic slip distribution patterns, all with identical seismic moment (Mw = 8.1). Analysis of the results indicates that for earthquakes of a fixed location, geometry, and seismic moment, peak nearshore tsunami amplitude can vary by a factor of 3 or more. These results indicate that there is substantially more variation in the local tsunami wave field derived from the inherent complexity subduction zone earthquakes than predicted by a simple elastic dislocation model. Probabilistic methods that take into account variability in earthquake rupture processes are likely to yield more accurate assessments of tsunami hazards.

Geist, E. L.

2002-01-01

295

E-W asymmetry and the generation of ESP events  

Energy Technology Data Exchange (ETDEWEB)

Observations of energetic-ion intensity enhancements (E <= 290 keV) associated with solar flare generated shock waves (solar flare ESP events), obtained during nearly a decade by the APL/JHU instruments on board the Earth orbiters IMP-7 and 8, are incorporated in this work in order to examine the role of the heliolongitude dependent large scale shock morphology with relation to the upstream interplanetary magnetic field in the formation of these ESP events. It is shown that a clear east-west solar hemisphere asymmetry is present in the distribution of the ESP relative intensity enhancements with respect to the heliolongitudes of the shock wave source-flare sites. The large ion-intensity enhancements super-imposed on the ambient solar flare ion population are preferentially associated with solar flare sites located to the east of the spacecraft meridian, whereas on the average only weak ESP events are associated with solar flare sites to the west of the spacecraft meridian. The observed asymmetry and its implications on the dominant processes for the generation of the solar flare ESP events are discussed on the basis of the presented extensive survey.

Sarris, E.T.; Anagnostopoulos, G.C.; Trochoutsos, P.C. (Democritos Univ. of Thrace, Xanthi (Greece))

1984-06-01

296

NiMax system for hadronic event generators in HEP  

International Nuclear Information System (INIS)

We have suggested a new approach to the development and use of Monte Carlo event generators in high-energy physics (HEP). It is a component approach, when a complex numerical model is composed of standard components. Our approach opens a way to organize a library of HEP model components and provides a great flexibility for the construction of very powerful and realistic numerical models. To support this approach we have designed the NiMax software system (framework) written in C++

2001-01-01

297

e+e- event generator EPOCS user's manual  

International Nuclear Information System (INIS)

EPOCS(Electron POsitron Collision Simulator) is a Monte-Carlo event generator for high energy e+e- annihilation. This program generates events based on the standard model, i.e., quantum chromodynamics (QCD) and electro-weak theory. It works at the center-of-mass energy below W+W- production, i.e., in the energy region of TRISTAN, SLC and LEP. For these high energy machines one of the important subjects is the exploration for the top quark. The production and hadronization of the top quark is included in EPOCS. Besides the top quark, we expect 'new' physics in this high energy region. EPOCS has enough flexibility for users to cope with a new idea. Users can register a new particle, modify the built-in particle data, define new primary interactions and so on. The event generator has a number of parameters, both physical parameters and control parameters. Users can control most of these parameters in EPOCS at will. (author).

1987-01-01

298

Database of tsunami scenario simulations for Western Iberia: a tool for the TRIDEC Project Decision Support System for tsunami early warning  

Science.gov (United States)

TRIDEC is a EU-FP7 Project whose main goal is, in general terms, to develop suitable strategies for the management of crises possibly arising in the Earth management field. The general paradigms adopted by TRIDEC to develop those strategies include intelligent information management, the capability of managing dynamically increasing volumes and dimensionality of information in complex events, and collaborative decision making in systems that are typically very loosely coupled. The two areas where TRIDEC applies and tests its strategies are tsunami early warning and industrial subsurface development. In the field of tsunami early warning, TRIDEC aims at developing a Decision Support System (DSS) that integrates 1) a set of seismic, geodetic and marine sensors devoted to the detection and characterisation of possible tsunamigenic sources and to monitoring the time and space evolution of the generated tsunami, 2) large-volume databases of pre-computed numerical tsunami scenarios, 3) a proper overall system architecture. Two test areas are dealt with in TRIDEC: the western Iberian margin and the eastern Mediterranean. In this study, we focus on the western Iberian margin with special emphasis on the Portuguese coasts. The strategy adopted in TRIDEC plans to populate two different databases, called "Virtual Scenario Database" (VSDB) and "Matching Scenario Database" (MSDB), both of which deal only with earthquake-generated tsunamis. In the VSDB we simulate numerically few large-magnitude events generated by the major known tectonic structures in the study area. Heterogeneous slip distributions on the earthquake faults are introduced to simulate events as "realistically" as possible. The members of the VSDB represent the unknowns that the TRIDEC platform must be able to recognise and match during the early crisis management phase. On the other hand, the MSDB contains a very large number (order of thousands) of tsunami simulations performed starting from many different simple earthquake sources of different magnitudes and located in the "vicinity" of the virtual scenario earthquake. In the DSS perspective, the members of the MSDB have to be suitably combined based on the information coming from the sensor networks, and the results are used during the crisis evolution phase to forecast the degree of exposition of different coastal areas. We provide examples from both databases whose members are computed by means of the in-house software called UBO-TSUFD, implementing the non-linear shallow-water equations and solving them over a set of nested grids that guarantee a suitable spatial resolution (few tens of meters) in specific, suitably chosen, coastal areas.

Armigliato, Alberto; Pagnoni, Gianluca; Zaniboni, Filippo; Tinti, Stefano

2013-04-01

299

Disturbance of Shallow Marine Soft-Bottom Environments and Megabenthos Assemblages by a Huge Tsunami Induced by the 2011 M9.0 Tohoku-Oki Earthquake  

Science.gov (United States)

Huge tsunami waves associated with megathrust earthquakes have a severe impact on shallow marine ecosystems. We investigated the impact of a tsunami generated by the 2011 M9.0 Tohoku-Oki earthquake on the seafloor and large benthic animals in muddy and sandy ria coasts (Otsuchi and Funakoshi bays) in northeastern Japan. We conducted underwater field surveys using scuba equipment in water depths of <20 m before the tsunami (September 2010) and after the tsunami (September 2011 and September 2012). During the study period, episodic changes in topography and grain-size composition occurred on the seafloor of the study area. Megabenthos sampling revealed a distinct pattern of distribution succession for each benthic species. For example, the protobranch bivalve Yoldia notabilis (Bivalvia: Nuculanidae) and the heterodont bivalve Felaniella usta (Bivalvia: Ungulinidae) disappeared after the tsunami event, whereas the distribution of the venus clam Gomphina melanaegis (Bivalvia: Veneridae) remained unchanged. In addition, the patterns of succession for a single species, such as the giant button top shell Umbonium costatum (Gastropoda: Trochidae) and the heart urchin Echinocardium cordatum (Echinoidea: Loveniidae), varied between the two bays studied. Our data also show that reestablishment of some benthic animal populations began within 18 months of the tsunami disturbance.

Seike, Koji; Shirai, Kotaro; Kogure, Yukihisa

2013-01-01

300

Disturbance of shallow marine soft-bottom environments and megabenthos assemblages by a huge tsunami induced by the 2011 M9.0 Tohoku-Oki earthquake.  

UK PubMed Central (United Kingdom)

Huge tsunami waves associated with megathrust earthquakes have a severe impact on shallow marine ecosystems. We investigated the impact of a tsunami generated by the 2011 M9.0 Tohoku-Oki earthquake on the seafloor and large benthic animals in muddy and sandy ria coasts (Otsuchi and Funakoshi bays) in northeastern Japan. We conducted underwater field surveys using scuba equipment in water depths of <20 m before the tsunami (September 2010) and after the tsunami (September 2011 and September 2012). During the study period, episodic changes in topography and grain-size composition occurred on the seafloor of the study area. Megabenthos sampling revealed a distinct pattern of distribution succession for each benthic species. For example, the protobranch bivalve Yoldia notabilis (Bivalvia: Nuculanidae) and the heterodont bivalve Felaniella usta (Bivalvia: Ungulinidae) disappeared after the tsunami event, whereas the distribution of the venus clam Gomphina melanaegis (Bivalvia: Veneridae) remained unchanged. In addition, the patterns of succession for a single species, such as the giant button top shell Umbonium costatum (Gastropoda: Trochidae) and the heart urchin Echinocardium cordatum (Echinoidea: Loveniidae), varied between the two bays studied. Our data also show that reestablishment of some benthic animal populations began within 18 months of the tsunami disturbance.

Seike K; Shirai K; Kogure Y

2013-01-01

 
 
 
 
301

Event trees and dynamic event trees: Applications to steam generator tube rupture accidents  

International Nuclear Information System (INIS)

The dynamic event tree analysis method (DETAM) is a simulation based approach that models the integrated, dynamic response of the plant/operating crew system to an accident. It extends the conventional event tree/fault tree methodology for accident sequence analysis in two ways. First, it allows for tree branchings at discrete points in time. Second, the tree sequences explicitly track changes in the operating crew state, as well as changes in the plant hardware state. Process variable calculations and operating procedures are used in linking the crew and hardware behaviour. - The paper compares the conventional event tree/fault tree methodology for accident sequence analysis with the dynamic event tree method in the analysis of a pressurized water reactor steam generator tube rupture. Two previous PSA analyses are used for the comparison. The first employs the ''event tree with boundary conditions'' approach and uses fairly detailed top event headings. The second employs the ''linked fault tree'' approach and uses a relatively small event tree. - A quantitative comparison of the results of the three analyses shows that, in this particularly case study, the DETAM results appear to be less conservative. This is due, in part, to DETAM's treatment of recovery actions embedded in the emergency operating procedures. The quantitative results, however, should be viewed with some caution, since: (a) the three analyses have different scopes and employ different assumptions, and (b) a number of the parameters used in the DETAM analysis are highly uncertain. - A qualitative comparison of results shows that the dominant sequences predicted by each methodology are similar. However, the DETAM scenario descriptions are more detailed and allow better definition of steps to reduce risk. Further, the DETAM models deal with the variety of human error forms and their consequences; this provides a better capability of identifying and quantifying complex accident scenarios that may not be treated in conventional PSA models. (author). 8 refs, 3 figs, 1 tab

1992-01-01

302

Monte-Carlo event generation for the LHC  

CERN Document Server

This thesis discusses recent developments for the simulation of particle physics in the light of the start-up of the Large Hadron Collider. Simulation programs for fully exclusive events, dubbed Monte-Carlo event generators, are improved in areas related to the perturbative as well as non-perturbative regions of strong interactions. A short introduction to the main principles of event generation is given to serve as a basis for the following discussion. An existing algorithm for the correction of parton-shower emissions with the help of exact tree-level matrix elements is revisited and significantly improved as attested by first results. In a next step, an automated implementation of the POWHEG method is presented. It allows for the combination of parton showers with full next-to-leading order QCD calculations and has been tested in several processes. These two methods are then combined into a more powerful framework which allows to correct a parton shower with full next-to-leading order matrix elements and h...

Siegert, Frank

303

Holocene Tsunami Deposits From Large Tsunamis Along the Kuril Subduction Zone, Northeast Japan  

Science.gov (United States)

Holocene tsunami deposits in eastern Hokkaido between Nemuro and Tokachi show that the Kuril subduction zone repeatedly produced earthquakes and tsunamis larger than those recorded in this region since AD 1804 (Nanayama et al., Nature, 424, 660-663, 2003). Twenty-two postulated tsunami sand layers from the past 9500 years are preserved on lake bottom near Kushiro City, and about ten postulated tsunami sand layers from the past 3000 years are preserved in peat layers on the coastal marsh of Kiritappu. We dated these ten tsunami deposits (named Ts1 to Ts10 from shallower to deeper) in peat layers by radiocarbon and tephrochronology, correlated them with historical earthquakes and tsunamis, and surveyed their spatial distribution to estimate the tsunamisO inland inundation limits. Ts10 and Ts9 are under regional tephra Ta-c2 (ca. 2.5 ka) and represent prehistorical events. Ts8 to Ts5 are between two regional tephra layers Ta-c2 and B-Tm (ca. 9th century). In particular, Ts5 is found just below B-Tm, so it is dated 9th century (Heian era). Ts4 is dated ca 13th century (Kamakura era), while Ts3, found just below Us-b and Ta-b (AD 1667-1663), is dated 17th century (Edo era). Ts2 is dated 19th century (Edo era) and may correspond to the AD 1843 Tempo Tokachi-oki earthquake (Mt 8.0) recorded in a historical document Nikkanki of Kokutai-ji temple at Akkeshi. Ts1 is inferred 20th century and may correspond to the tsunami from the AD 1960 Chilean earthquake (M 9.5) or the AD 1952 Tokachi-oki earthquake (Mt 8.2). Our detailed surveys indicate that Ts3 and Ts4 can be traced more than 3 km from the present coast line in Kirittapu marsh, much longer than the limits (< 1 km) of recent deposits Ts1 and Ts2 or documented inundation of the 19th and 20th century tsunamis. The recurrence intervals of great tsunami inundation are about 400 to 500 years, longer than that of typical interplate earthquakes along the Kuril subduction zone. The longer interval and the apparent large tsunami inundation indicate unusual origin of these tsunamis.

Nanayama, F.; Furukawa, R.; Satake, K.; Soeda, Y.; Shigeno, K.

2003-12-01

304

Community variations in social vulnerability to Cascadia-related tsunamis in the U.S. Pacific Northwest  

Science.gov (United States)

Tsunamis generated by Cascadia subduction zone earthquakes pose significant threats to coastal communities in the U. S. Pacific Northwest. Impacts of future tsunamis to individuals and communities will likely vary due to pre-event socioeconomic and demographic differences. In order to assess social vulnerability to Cascadia tsunamis, we adjust a social vulnerability index based on principal component analysis first developed by Cutter et al. (2003) to operate at the census-block level of geography and focus on community-level comparisons along the Oregon coast. The number of residents from blocks in tsunami-prone areas considered to have higher social vulnerability varies considerably among 26 Oregon cities and most are concentrated in four cities and two unincorporated areas. Variations in the number of residents from census blocks considered to have higher social vulnerability in each city do not strongly correlate with the number of residents or city assets in tsunami-prone areas. Methods presented here will help emergency managers to identify community sub-groups that are more susceptible to loss and to develop risk-reduction strategies that are tailored to local conditions. ?? z.

Wood, N. J.; Burton, C. G.; Cutter, S. L.

2010-01-01

305

The Physics of Tsunamis  

Science.gov (United States)

This web site provides a set of simple tutorials on the physics of tsunamis. Each tutorial is presented in clear, straightforward language, with multiple animations and simulations to depict how these destructive waves originate and propagate. This item is part of a larger set of resources on tsunamis developed and maintained by the Earth and Space Sciences project at the University of Washington.

2009-03-10

306

Computational particle physics for event generators and data analysis  

Science.gov (United States)

High-energy physics data analysis relies heavily on the comparison between experimental and simulated data as stressed lately by the Higgs search at LHC and the recent identification of a Higgs-like new boson. The first link in the full simulation chain is the event generation both for background and for expected signals. Nowadays event generators are based on the automatic computation of matrix element or amplitude for each process of interest. Moreover, recent analysis techniques based on the matrix element likelihood method assign probabilities for every event to belong to any of a given set of possible processes. This method originally used for the top mass measurement, although computing intensive, has shown its efficiency at LHC to extract the new boson signal from the background. Serving both needs, the automatic calculation of matrix element is therefore more than ever of prime importance for particle physics. Initiated in the 80's, the techniques have matured for the lowest order calculations (tree-level), but become complex and CPU time consuming when higher order calculations involving loop diagrams are necessary like for QCD processes at LHC. New calculation techniques for next-to-leading order (NLO) have surfaced making possible the generation of processes with many final state particles (up to 6). If NLO calculations are in many cases under control, although not yet fully automatic, even higher precision calculations involving processes at 2-loops or more remain a big challenge. After a short introduction to particle physics and to the related theoretical framework, we will review some of the computing techniques that have been developed to make these calculations automatic. The main available packages and some of the most important applications for simulation and data analysis, in particular at LHC will also be summarized (see CCP2012 slides [1]).

Perret-Gallix, Denis

2013-08-01

307

Development and application of the hadronic event generators in HEP  

International Nuclear Information System (INIS)

[en] We have suggested a new approach to the development and use of Monte Carlo event generators in high-energy physics (HEP). It is a component approach where a complex numerical model is composed from standardized components. Our approach opens a way to organize a library of HEP model components and provides a great deal of flexibility for the construction of powerful and realistic numerical models. To support this approach, we have designed the NiMax software system (framework) that is written in C++

2004-01-01

308

Development and application of the hadronic event generators in HEP  

International Nuclear Information System (INIS)

[en] It is suggested a new approach to the development and use of Monte Carlo event generators in high-energy physics (HEP). It is a component approach, when complex numerical model is composed from standardized components. The approach opens a way to organize library of HEP model components and provides a great flexibility for the construction of powerful and realistic numerical models. To support this approach is designed the NiMax software system that is written in C++[ru] ????????? ????? ?????? ? ?????????? ? ????????????? ?????????? ??????? ?? ?????? ?????-????? ??? ?????? ??????? ???????. ? ???? ??????? ????????? ?????? (??) ???????????? ?? ??????????? ?????????, ? ?????????? ???? ?????????? ?????????? ????????? ??. ??? ???????????? ???????? ? ?????????? ??????????? ? ???????????? ??. ??? ????????? ????? ??????? ????????????? ??????? ??????????? NiMax ?? ????? ?++

2004-01-01

309

THE TSUNAMI ASSESSMENT MODELLING SYSTEM BY THE JOINT RESEARCH CENTRE  

Directory of Open Access Journals (Sweden)

Full Text Available The Tsunami Assessment Modeling System was developed by the European Commission, Joint Research Centre, in order to serve Tsunami early warning systems such as the Global Disaster Alerts and Coordination System (GDACS) in the evaluation of possible consequences by a Tsunami of seismic nature. The Tsunami Assessment Modeling System is currently operational and is calculating in real time all the events occurring in the world, calculating the expected Tsunami wave height and identifying the locations where the wave height should be too high. The first part of the paper describes the structure of the system, the underlying analytical models and the informatics arrangement; the second part shows the activation of the system and the results of the calculated analyses. The final part shows future development of this modeling tool.

Alessandro Annunziato

2007-01-01

310

Real-time earthquake monitoring for tsunami warning in the Indian Ocean and beyond  

Directory of Open Access Journals (Sweden)

Full Text Available The Mw = 9.3 Sumatra earthquake of 26 December 2004 generated a tsunami that affected the entire Indian Ocean region and caused approximately 230 000 fatalities. In the response to this tragedy the German government funded the German Indonesian Tsunami Early Warning System (GITEWS) Project. The task of the GEOFON group of GFZ Potsdam was to develop and implement the seismological component. In this paper we describe the concept of the GITEWS earthquake monitoring system and report on its present status. The major challenge for earthquake monitoring within a tsunami warning system is to deliver rapid information about location, depth, size and possibly other source parameters. This is particularly true for coast lines adjacent to the potential source areas such as the Sunda trench where these parameters are required within a few minutes after the event in order to be able to warn the population before the potential tsunami hits the neighbouring coastal areas. Therefore, the key for a seismic monitoring system with short warning times adequate for Indonesia is a dense real-time seismic network across Indonesia with densifications close to the Sunda trench. A substantial number of supplementary stations in other Indian Ocean rim countries are added to strengthen the teleseismic monitoring capabilities. The installation of the new GITEWS seismic network – consisting of 31 combined broadband and strong motion stations – out of these 21 stations in Indonesia – is almost completed. The real-time data collection is using a private VSAT communication system with hubs in Jakarta and Vienna. In addition, all available seismic real-time data from the other seismic networks in Indonesia and other Indian Ocean rim countries are acquired also directly by VSAT or by Internet at the Indonesian Tsunami Warning Centre in Jakarta and the resulting "virtual" network of more than 230 stations can jointly be used for seismic data processing. The seismological processing software as part of the GITEWS tsunami control centre is an enhanced version of the widely used SeisComP software and the well established GEOFON earthquake information system operated at GFZ in Potsdam (http://geofon.gfz-potsdam.de/db/eqinfo.php). This recently developed software package (SeisComP3) is reliable, fast and can provide fully automatic earthquake location and magnitude estimates. It uses innovative visualization tools, offers the possibility for manual correction and re-calculation, flexible configuration, support for distributed processing and data and parameter exchange with external monitoring systems. SeisComP3 is not only used for tsunami warning in Indonesia but also in most other Tsunami Warning Centres in the Indian Ocean and Euro-Med regions and in many seismic services worldwide.

W. Hanka; J. Saul; B. Weber; J. Becker; P. Harjadi; Fauzi; GITEWS Seismology Group

2010-01-01

311

Modelisation of the impact of tsunamis and free oscillation in French Polynesia  

Science.gov (United States)

The agitation inside basins (closed or semi-enclosed) depends on the period of the waves which force agitation, reflection and energy dissipation, characteristics of the boundary and the geometrical properties of the basin. When waves continuously enter the basin, they cause abnormal water level fluctuations and unexpected damage if their periods are close to those of free oscillation of the basin. These are called resonant oscillations. The resonant oscillations inside harbors, bays, or other semi-enclosed or closed basins can have a direct influence on the management of harbors, shipping and coastal uses. So, it is important to determine these free oscillations. These resonant characteristics were observed in the Marquesas archipelago (French Polynesia) during the Samoa tsunami of 29/09/2009 (Mw 8.0). They had previously been observed for the tsunamis generated by Kurile earthquakes (November 2006 and January 2007), Chilean and Peruvian earthquakes (August and November 2007). According to the observations of the tsunami produced by the Samoa earthquake, strong amplification and a long duration of water agitation were reported in this archipelago. Observations coming from monitored bays and human reports make this event among the important tsunamis recorded in the Marquesas. In this archipelago there are two monitored bays: the first, located in Hiva Oa Island (Tahauku bay), recorded an amplitude of 40 cm and 2 days of agitation. The second in Nuku Hiva Island (Taihoae bay) had an amplitude of 45 cm and 3 days of agitation. During last century, this archipelago has been frequently hit by several trans-Pacific tsunamis. It is interesting to note that, following different tsunami reports, the bays had different responses depending on the region of the earthquake source. For instance, Tahauku and Atuona, two bays in Hiva Oa Island distant 1 km apart, have different effects depending on the tsunami, as it was observed in 1946 (Aleutian earthquake) and 1960 (Chile earthquake). In this study, we determine the periods of oscillations (eigenperiods). To this aim, we use the real tide gauge data, and numerical tsunami simulation (based on non linear shallow water theory) to make spectral analysis based on Fourier transform and frequency-time analysis of the real seismic sources. We also use synthetics sources to study the possible azimuthal dependence of excitation of these eigenperiods. An alternative way to determine free oscillations is to use analytic calculation of different eigenfunctions of the wave equation to find the oscillations periods.

Allgeyer, Sébastien; Hébert, Hélène; Madariaga, Raúl

2010-05-01

312

Real-time earthquake monitoring for tsunami warning in the Indian Ocean and beyond  

Science.gov (United States)

The Mw = 9.3 Sumatra earthquake of 26 December 2004 generated a tsunami that affected the entire Indian Ocean region and caused approximately 230 000 fatalities. In the response to this tragedy the German government funded the German Indonesian Tsunami Early Warning System (GITEWS) Project. The task of the GEOFON group of GFZ Potsdam was to develop and implement the seismological component. In this paper we describe the concept of the GITEWS earthquake monitoring system and report on its present status. The major challenge for earthquake monitoring within a tsunami warning system is to deliver rapid information about location, depth, size and possibly other source parameters. This is particularly true for coast lines adjacent to the potential source areas such as the Sunda trench where these parameters are required within a few minutes after the event in order to be able to warn the population before the potential tsunami hits the neighbouring coastal areas. Therefore, the key for a seismic monitoring system with short warning times adequate for Indonesia is a dense real-time seismic network across Indonesia with densifications close to the Sunda trench. A substantial number of supplementary stations in other Indian Ocean rim countries are added to strengthen the teleseismic monitoring capabilities. The installation of the new GITEWS seismic network - consisting of 31 combined broadband and strong motion stations - out of these 21 stations in Indonesia - is almost completed. The real-time data collection is using a private VSAT communication system with hubs in Jakarta and Vienna. In addition, all available seismic real-time data from the other seismic networks in Indonesia and other Indian Ocean rim countries are acquired also directly by VSAT or by Internet at the Indonesian Tsunami Warning Centre in Jakarta and the resulting "virtual" network of more than 230 stations can jointly be used for seismic data processing. The seismological processing software as part of the GITEWS tsunami control centre is an enhanced version of the widely used SeisComP software and the well established GEOFON earthquake information system operated at GFZ in Potsdam (http://geofon.gfz-potsdam.de/db/eqinfo.php). This recently developed software package (SeisComP3) is reliable, fast and can provide fully automatic earthquake location and magnitude estimates. It uses innovative visualization tools, offers the possibility for manual correction and re-calculation, flexible configuration, support for distributed processing and data and parameter exchange with external monitoring systems. SeisComP3 is not only used for tsunami warning in Indonesia but also in most other Tsunami Warning Centres in the Indian Ocean and Euro-Med regions and in many seismic services worldwide.

Hanka, W.; Saul, J.; Weber, B.; Becker, J.; Harjadi, P.; Fauzi; Gitews Seismology Group

2010-12-01

313

Safety evaluation of nuclear power plant against the virtual tsunami  

International Nuclear Information System (INIS)

The main scope of this study is the numerical analysis of virtual tsunami event near the Ulchin Nuclear Power Plants. In the numerical analysis, the maximum run-up height and draw-down are estimated at the Ulchin Nuclear Power Plants. The computer program developed in this study describes the propagation and associated run-up process of tsunamis by solving linear and nonlinear shallow-water equations with finite difference methods. It can be used to check the safety of a nuclear power plant against tsunami attacks. The program can also be used to calculate run-up height of wave and provide proper design criteria for coastal facilities and structures. A maximum inundation zone along the coastline can be developed by using the moving boundary condition. As a result, it is predicted that the Ulchin Nuclear Power Plants might be safe against the virtual tsunami event. Although the Ulchin Nuclear Power Plants are safe against the virtual tsunami event, the occurrence of a huge tsunami in the seismic gap should be investigated in detail. Furthermore, the possibility of nearshore tsunamis around the Korean Peninsula should also be studied and monitored continuously.

2004-01-01

314

Heavy ion event generator HYDJET++ (HYDrodynamics plus JETs)  

Science.gov (United States)

HYDJET++ is a Monte Carlo event generator for simulation of relativistic heavy ion AA collisions considered as a superposition of the soft, hydro-type state and the hard state resulting from multi-parton fragmentation. This model is the development and continuation of HYDJET event generator (Lokhtin and Snigirev, EPJC 45 (2006) 211). The main program is written in the object-oriented C++ language under the ROOT environment. The hard part of HYDJET++ is identical to the hard part of Fortran-written HYDJET and it is included in the generator structure as a separate directory. The soft part of HYDJET++ event is the “thermal” hadronic state generated on the chemical and thermal freeze-out hypersurfaces obtained from the parameterization of relativistic hydrodynamics with preset freeze-out conditions. It includes the longitudinal, radial and elliptic flow effects and the decays of hadronic resonances. The corresponding fast Monte Carlo simulation procedure, C++ code FAST MC (Amelin et al., PRC 74 (2006) 064901; PRC 77 (2008) 014903) is adapted to HYDJET++. It is designed for studying the multi-particle production in a wide energy range of heavy ion experimental facilities: from FAIR and NICA to RHIC and LHC. Catalogue identifier: AECR_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AECR_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 100?387 No. of bytes in distributed program, including test data, etc.: 797?019 Distribution format: tar.gz Programming language: C++ (however there is a Fortran-written part which is included in the generator structure as a separate directory) Computer: Hardware independent (both C++ and Fortran compilers and ROOT environment [1] (http://root.cern.ch/) should be installed) Operating system: Linux (Scientific Linux, Red Hat Enterprise, FEDORA, etc.) RAM: 50 MBytes (determined by ROOT requirements) Classification: 11.2 External routines: ROOT [1] (http://root.cern.ch/) Nature of problem: The experimental and phenomenological study of multi-particle production in relativistic heavy ion collisions is expected to provide valuable information on the dynamical behavior of strongly-interacting matter in the form of quark-gluon plasma (QGP) [2-4], as predicted by lattice Quantum Chromodynamics (QCD) calculations. Ongoing and future experimental studies in a wide range of heavy ion beam energies require the development of new Monte Carlo (MC) event generators and improvement of existing ones. Especially for experiments at the CERN Large Hadron Collider (LHC), implying very high parton and hadron multiplicities, one needs fast (but realistic) MC tools for heavy ion event simulations [5-7]. The main advantage of MC technique for the simulation of high-multiplicity hadroproduction is that it allows a visual comparison of theory and data, including if necessary the detailed detector acceptances, responses and resolutions. The realistic MC event generator has to include maximum possible number of observable physical effects, which are important to determine the event topology: from the bulk properties of soft hadroproduction (domain of low transverse momenta p?1 GeV/c) such as collective flows, to hard multi-parton production in hot and dense QCD-matter, which reveals itself in the spectra of high-p particles and hadronic jets. Moreover, the role of hard and semi-hard particle production at LHC can be significant even for the bulk properties of created matter, and hard probes of QGP became clearly observable in various new channels [8-11]. In the majority of the available MC heavy ion event generators, the simultaneous treatment of collective flow effects for soft hadroproduction and hard multi-parton in-medium production (medium-induced partonic rescattering and energy loss, so-called “jet quenching”) is lacking. Thus, in order to analyze existing data on low and high-p hadron production

Lokhtin, I. P.; Malinina, L. V.; Petrushanko, S. V.; Snigirev, A. M.; Arsene, I.; Tywoniuk, K.

2009-05-01

315

MARTINI: An event generator for relativistic heavy-ion collisions  

International Nuclear Information System (INIS)

We introduce the modular algorithm for relativistic treatment of heavy ion interactions (MARTINI), a comprehensive event generator for the hard and penetrating probes in high-energy nucleus-nucleus collisions. Its main components are a time-evolution model for the soft background, PYTHIA 8.1, and the McGill-Arnold, Moore, and Yaffe (AMY) parton-evolution scheme, including radiative as well as elastic processes. This allows us to generate full event configurations in the high pT region that take into account thermal quantum chromodynamic (QCD) and quantum electrodynamic (QED) effects as well as effects of the evolving medium. We present results for the neutral pion nuclear modification factor in Au+Au collisions at the BNL Relativistic Heavy Ion Collider as a function of pT for different centralities and also as a function of the angle with respect to the reaction plane for noncentral collisions. Furthermore, we study the production of high-transverse-momentum photons, incorporating a complete set of photon-production channels.

2009-01-01

316

SEVERAL TSUNAMI SCENARIOS AT THE NORTH SEA AND THEIR CONSEQUENCES AT THE GERMAN BIGHT  

Directory of Open Access Journals (Sweden)

Full Text Available Tsunamis occurred in the past at the North Sea, but not frequently. There are historical and geological records of several tsunamis: the Storegga tsunami caused sediment deposits in Scotland 8,000 years ago and records of at least six earthquake-generated tsunamis exist from 842 to 1761 AC. The highest tsunami height witnessed at the German Bight is comparable to the maximum storm surge recorded and could thus cause similar or higher damage. However, there is little research on tsunami modeling in the North Sea. Here, we performed ten numerical experiments imposing N-waves at the open boundaries of a North Sea model system to study the potential consequences of tsunamis for the German Bight. One of the experiments simulated the second Storegga slide tsunami, seven more explored the influence of the incidence direction of the tsunami when entering the North Sea domain, and the other two explored the influence of tides on tsunami heights. We found that the German Bight is not exempt from tsunami risk. The main impact was from waves entering the North Sea from the north, even for tsunamis with sources south of the North Sea. Waves entering from the English Channel were attenuated after crossing the Dover strait. For some scenarios, the tsunami energy got focused directly at the Frisian Islands. The tidal phase had a strong influence on tsunami heights, although in this study the highest heights were obtained in the absence of tides. The duration of tsunamis is significantly smaller than that of storm surges, even though their flow velocities were found to be comparable or larger, thus increasing their possible damage. Therefore, tsunamis should not be dismissed as a threat at the North Sea basin and particularly at the German Bight.

Silvia Chacón-Barrantes; Rangaswami Narayanan; Roberto Mayerle

2013-01-01

317

Preliminary evidence for a 1000-year-old tsunami in the South China Sea.  

UK PubMed Central (United Kingdom)

The risk of large, devastating tsunamis in the South China Sea and its surrounding coastal region is commonly underestimated or unrecognized due to the difficulty of differentiating tsunami from storm deposits. As a consequence, few convincing records have documented tsunami deposits in this region. Here we report preliminary evidence from Xisha Islands in the South China Sea for a large tsunami around AD 1024. Sand layers in lake sediment cores and their geochemical characteristics indicate a sudden deposition event around AD 1024, temporally consistent with a written record of a disastrous event characterized by high waves in AD 1076. Heavy coral and shell fossils, which are older than AD 1024, deposited more than 200?meters into the island, further support the occurrence of a high-energy event such as a tsunami or an unusually large storm. Our results underscore the importance of acknowledging and understanding the tsunami hazard in this area.

Sun L; Zhou X; Huang W; Liu X; Yan H; Xie Z; Wu Z; Zhao S; Da Shao; Yang W

2013-01-01

318

CATASTROPHIC FLANK COLLAPSE ON TA’U ISLAND AND SUBSEQUENT TSUNAMI: HAS THIS OCCURRED DURING THE LAST 170 YEARS?  

Directory of Open Access Journals (Sweden)

Full Text Available Ta’u, the easternmost inhabited island in the Samoan Islands archipelago, exhibits a series of down-faulted benches on its southern flank, believed to be the remnant of ~30 km3 catastrophic collapse. A historical map of Ta’u charted in 1839 during the United States Exploring Expedition, which did not show the benches, suggests that the event occurred less than 170 years ago. A collapse event of this magnitude would have generated a locally devastating tsunami, with possible impacts experienced at the regional level. However, no written or oral records of such an event exist. A number of key questions thus emerge, and formed the basis for this study. Did this event actually happen within the last 170 years, and if so, how and why could it have gone unnoticed? Or, is the event much older than the impression obtained from the literature? The catastrophic flank collapse was modeled using 100 m contour-resolution bathymetry data of the Ta’u region, coupled with rational assumptions made on the geometry of the failed mass. This enabled numerical landslide- tsunami simulation in the Cornell Multigrid Coupled Tsunami Model (COMCOT). The results indicate that if an event of this magnitude occurred in the last 170 years, it could not have gone unnoticed by local inhabitants. It thus seems likely that the initial survey conducted during the Exploring Expedition was inaccurate. Nevertheless, the well-preserved nature of the benches indicates collapse relatively recently and raises the possibility of future collapse.

Shaun Williams; Tim Davies; Jim Cole

2012-01-01

319

Next-Generation Navigational Infrastructure and the ATLAS Event Store  

CERN Multimedia

The ATLAS event store employs a persistence framework with extensive navigational capabilities. These include real-time back navigation to upstream processing stages, externalizable data object references, navigation from any data object to any other both within a single file and across files, and more. The 2013-2014 shutdown of the Large Hadron Collider provides an opportunity to enhance this infrastructure in several ways that both extend these capabilities and allow the collaboration to better exploit emerging computing platforms. Enhancements include redesign with efficient file merging in mind, content-based indices in optimized reference types, and support for forward references. The latter provide the potential to construct valid references to data before those data are written, a capability that is useful in a variety of multithreading, multiprocessing, distributed processing, and deferred processing scenarios. This paper describes the architecture and design of the next generation of ATLAS navigation...

van Gemmeren, P; The ATLAS collaboration; Nowak, M

2013-01-01

320

Hipse: an event generator for nuclear collisions at intermediate energies  

Energy Technology Data Exchange (ETDEWEB)

An event generator, HIPSE (Heavy-Ion Phase-Space Exploration), dedicated to the description of nuclear collisions in the intermediate energy range is presented. Based on the sudden approximation and on geometrical hypothesis, it can conveniently simulate heavy-ion interactions at all impact parameters and thus can constitute a valuable tool for the understanding of processes such as neck emission or multifragmentation in peripheral or/and central collisions. After a detailed description of the ingredients of the model, first comparisons with experimental data collected by the INDRA collaboration are shown. Special emphasis is put on the kinematical characteristics of fragments and light particles observed at all impact parameters for Xe+Sn reactions at 25 and 50 MeV/u and Ni + Ni at 82 MeV/u. (authors)

Lacroix, D.; Van Lauwe, A.; Durand, D

2003-11-01

 
 
 
 
321

Simulations of Tsunami Hazard from Regional Sources in the South China and Adjoining Seas  

Science.gov (United States)

We examine the tsunami potential from sources located in the South China Sea and its adjoining basins, the Sulu and Sulawezi Seas, by running simulations using the MOST code for a number of scenarios of possible earthquakes at the various local subduction zones. In the Sulawezi Sea, we consider the events of 1918 at the Mindanao subduction zone, and 1996 at the Northern end of the Makassar Strait. In the Sulu Sea, we consider a scenario inspired by the 1948 Panay earthquake (because of the fractured nature of the plate system in those areas, it is not feasible to consider much larger earthquakes). In all three cases, we find that the tsunami is contained within the relevant marginal sea and does not penetrate significantly the greater South China Basin, but could cause significant damage to the Eastern coast of Borneo. Farther North, we consider as worst case scenarios events reaching 10**29 dyn*cm with rupture lengths of 400 km, both off Luzon Island and, under a slightly different geometry, off the Luzon Straits separating the Philippines and Taiwan. Such scenarios carry very significant hazard to all coastlines bordering the South China Sea, including Indochina and Borneo. We will also present models of landslide-generated tsunamis, inspired from the event of 14 February 1934 off the Luzon Strait, and the presumably Holocene Brunei mega-slide.

Kalligeris, N.; Synolakis, C. E.; Okal, E. A.

2008-12-01

322

Candidate Tsunami Deposits at Carpinteria Salt Marsh, Southern California  

Science.gov (United States)

Carpinteria Salt Marsh, 15 km southeast of Santa Barbara, California preserves geologic evidence of possible past tsunami inundation along the southern California coast. The proximity of the Santa Barbara coastline to the Goleta slide complex and to numerous offshore faults in the Santa Barbara basin suggests a potential for moderate to large tsunamis. A field investigation in February 2008 collected more than 60 cores and examined 8 cutbank exposures throughout the marsh. Sand layers consistent with tsunami deposition were found at depths from 35 to 96 cm in cores from four areas within the marsh. The sand layers, which range from 1 cm to 35 cm thick and extend up to 630 m inland, had sharp lower contacts and were often normally graded. In addition, in some cores there were one or more intervening mud layers within the sand layer. Composition and angularity of the sand is similar to sands found in the surrounding beach, dune, and nearshore environments. While the sand layers occur at similar depths in the cores, they were concentrated in four areas that were isolated by regions with no evidence of tsunami deposition. The deposits may represent spatially discontinuous deposition from one event, spatially continuous deposition from one event with poor preservation of the deposits, or deposition from more than one event. Discontinuous deposition from one event is in contrast to spatially continuous sheet deposition characteristic of moderate to large tsunamis, but may represent isolated deposition by a smaller tsunami along channel banks. The deposit is more consistent with tsunami deposition than deposition by other event-driven processes such as storms or floods. However, marsh processes that may create normally graded sand layers such as channel migration must also be considered before accepting a tsunami origin for the deposits.

Peters, R.; Jaffe, B. E.; Buckley, M.; Watt, S. G.

2008-12-01

323

The tsunami warning center in Alaska  

International Nuclear Information System (INIS)

The Alaska Tsunami Warning Center (ATWC) has implemented many major changes in order to provide timely and effective tsunami warning services for coastal populations in Alaska, and the west coasts of Canada and the lower 48 States. The basis for these improvements was the integration of computers and associated developments into the ATWC's operations. New concepts, technique developments, procedures, computers, and equipment were implemented which resulted in a highly automated warning system which analyzes data from potential tsunamigenic earthquakes in real-time, and immediately disseminates necessary critical information to affected coastal populations. These advancements are leading toward an automated expert system. The present system has been exercised for seven recent potential tsunamigenic earthquakes and has proven to be very timely with tsunami warnings being issued in an average of 11 minutes after the origin time of an earthquake. Seismic and tide data networks have been enlarged to improve the accuracy and timeliness in locating and sizing earthquakes, and for confirming the existence of a tsunami. New techniques and equipment are being implemented to collect, analyze and process tide data via micro computers. All critical warning and watch information messages are generated by computers which are linked to a satellite and high speed teletypewriter communication systems for rapid dissemination of information. The ATWC's community preparedness efforts have been expanded to aid those individuals who may be caught in the immediate vicinity of a violent earthquake and its subsequent tsunami. (author). 14 refs, 6 figs.

1989-01-01

324

MODELING THE LA PALMA LANDSLIDE TSUNAMI  

Directory of Open Access Journals (Sweden)

Full Text Available The tsunami expected from a lateral collapse of the Cumbre Vieja Volcano on La Palma in the Canary Islands was modeled. The flank collapse for a ‘worst case” landslide was modeled as a 650 meter high, 20 kilometer radius water wave after 30 kilometers of travel as predicted by physical modeling studies of Fritz at ETH in Zurich, Switzerland.The modeling was performed using the SWAN code which solves the nonlinear long waver equations. The tsunami generation and propagation was modeled using a 10 minute Mercator grid of 600 by 640 cells. The small wavelength and period of the tsunami expected from the landslide source results in an intermediate wave rather than a shallow water tsunami wave. The use of a shallow water model only describes the geometric spreasing of the wave and not the significant dispersion such a short period wave would exhibit. Dispersion would reduce the wave amplitudes to less than one-third of the shallow water amplitudes.The upper limit shallow water modeling indicates that the east coast of the U.S.A. and the Caribbean would receive tsunami waves less than 3 meters high. The European and African coasts would have waves less than 10 meters high.Full Navier-Stokes modeling including dispersion and geometric spreading for the Fritz initial wave profile predicts that the maximim wave amplitude off the U.S. east coast would be about a meter. Even with shoaling the wave would not present a significant hazard.

Charles L. Mader

2001-01-01

325

Numerical Simulation of Tsunamis.  

Science.gov (United States)

Two-dimensional, time-dependent, nonlinear, incompressible, viscous flow calculations were performed of realistic models of tsunami waves interacting with continental slopes and shelves. Wave heights were observed to grow by a factor of 4 as they shoaled ...

C. L. Mader

1973-01-01

326

Tsunami Travel Time Approximation  

Science.gov (United States)

Eric Grosfils, Pomona College Summary Students are asked to calculate approximate tsunami travel times across the Pacific basin. The assignment builds off of a lab introducing students to Spatial Analyst, and ...

Grosfils, Eric

327

Técnicas histórico-etnográficas en la reconstrucción y caracterización de tsunamis: el ejemplo del gran tsunami del 22 de junio de 1932, en las costas del Pacífico mexicano  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish La magnitud de los desastres ocasionados por tsunamis en la última década ha motivado a ampliar el conocimiento sobre su dinámica y comportamiento. Este estudio propone la aplicación de técnicas de análisis multidisciplinarias, incluyendo las histórico-etnográficas en la reconstrucción y caracterización de los tsunamis sin un registro instrumental. Se usa el ejemplo del tsunami del 22 de junio de 1932, el segundo más destructivo registrado en las costas del Pac (more) ífico mexicano. El origen del tsunami es incierto y se plantean dos hipótesis: 1) sísmico, y 2) por un deslizamiento submarino. Archivos históricos, entrevistas y mapeo en Sistemas de Información Geográfica permitieron identificar componentes clave de la dinámica del tsunami: tiempo de arribo, directividad, superficie afectada y alturas máximas de ola en la costa. Se aplicaron modelos numéricos (GEOWAVE y FUNWAVE) basados en datos históricos, usando dos posibles mecanismos de generación. Los resultados demuestran que un deslizamiento submarino explica mejor la causa del tsunami de 1932. Abstract in english The magnitude of damage caused by tsunamis in the past decade has encouraged scientists to expand our knowledge about tsunami dynamics and behavior. This study applies a multidisciplinary analysis, including historical and ethnographic techniques, in the reconstruction and characterization of tsunamis with no instrumental record. The example of the 22 June 1932 tsunami, the second most destructive recorded in the Pacific Coast of Mexico is used. The cause of this tsunami (more) is uncertain. Two hypotheses are proposed: 1) seismic slip, and 2) a submarine landslide. Historical archives, interviews with local witnesses, and GIS mapping, aided in identifying key components of the tsunami dynamics: arrival time, directivity, affected area, and maximum wave heights at the coast. Based on historical data, we applied numerical models (GEOWAVE and FUNWAVE codes) to the two possible mechanisms of tsunami generation. The results show that a submarine landslide explains best the cause of the 1932 tsunami.

Morales, Corona; Ramírez-Herrera, Teresa

2012-12-01

328

Foam A General Purpose Cellular Monte Carlo Event Generator  

CERN Multimedia

A general purpose, self-adapting, Monte Carlo (MC) event generator (simulator) is described. The high efficiency of the MC, that is small maximum weight or variance of the MC weight is achieved by means of dividing the integration domain into small cells. The cells can be $n$-dimensional simplices, hyperrectangles or Cartesian product of them. The grid of cells, called ``foam'', is produced in the process of the binary split of the cells. The choice of the next cell to be divided and the position/direction of the division hyper-plane is driven by the algorithm which optimizes the ratio of the maximum weight to the average weight or (optionally) the total variance. The algorithm is able to deal, in principle, with an arbitrary pattern of the singularities in the distribution. As any MC generator, it can also be used for the MC integration. With the typical personal computer CPU, the program is able to perform adaptive integration/simulation at relatively small number of dimensions ($\\leq 16$). With the continu...

Jadach, Stanislaw

2003-01-01

329

Evaluation of multiple steam generator tube rupture events for KNGR  

International Nuclear Information System (INIS)

The likelihood that steam generator tube ruptures (SGTR) will result in containment bypass is reduced by specific Korean Next Generation Reactor (KNGR) design features. Added features, relative to the Korean Standard Nuclear Power Plant (KSNP) Nuclear Steam Supply System (NSSS) Design, include modifications to assure continuity of steam bypass capability following a safety injection actuation signal. These changes significantly enhance the capability to avoid containment bypass via opening of the Main Steam Safety Valves (MSSVs) during a SGTR relative to the KSNP design. Thermal-hydraulic analyses are performed using RELAP5/MOD3 to evaluate the effectiveness of the added features. The significant result of the analyses is the length of time between event initiation and opening of the MSSVs. With only automatic response of plant systems, this time varies from greater than 4 hours for rupture of one tube to 30 minutes for rupture of five tubes. This paper presents the results of the analyses for 1 tube rupture and 5 tubes rupture cases.

1999-01-01

330

Tsunami Early Warning Within Five Minutes  

Science.gov (United States)

Tsunamis are most destructive at near to regional distances, arriving within 20-30 min after a causative earthquake; effective early warning at these distances requires notification within 15 min or less. The size and impact of a tsunami also depend on sea floor displacement, which is related to the length, L, width, W, mean slip, D, and depth, z, of the earthquake rupture. Currently, the primary seismic discriminant for tsunami potential is the centroid-moment tensor magnitude, M {w/CMT}, representing the product LWD and estimated via an indirect inversion procedure. However, the obtained M {w/CMT} and the implied LWD value vary with rupture depth, earth model, and other factors, and are only available 20-30 min or more after an earthquake. The use of more direct discriminants for tsunami potential could avoid these problems and aid in effective early warning, especially for near to regional distances. Previously, we presented a direct procedure for rapid assessment of earthquake tsunami potential using two, simple measurements on P-wave seismograms—the predominant period on velocity records, T d , and the likelihood, T {50/Ex}, that the high-frequency, apparent rupture-duration, T 0, exceeds 50-55 s. We have shown that T d and T 0 are related to the critical rupture parameters L, W, D, and z, and that either of the period-duration products T d T 0 or T d T {50/Ex} gives more information on tsunami impact and size than M {w/CMT}, M wp, and other currently used discriminants. These results imply that tsunami potential is not directly related to the product LWD from the "seismic" faulting model, as is assumed with the use of the M {w/CMT} discriminant. Instead, information on rupture length, L, and depth, z, as provided by T d T 0 or T d T {50/Ex}, can constrain well the tsunami potential of an earthquake. We introduce here special treatment of the signal around the S arrival at close stations, a modified, real-time, M wpd(RT) magnitude, and other procedures to enable early estimation of event parameters and tsunami discriminants. We show that with real-time data currently available in most regions of tsunami hazard, event locations, m b and M wp magnitudes, and the direct, period-duration discriminant, T d T {50/Ex} can be determined within 5 min after an earthquake occurs, and T 0, T d T 0, and M wpd(RT) within approximately 10 min. This processing is implemented and running continuously in real-time within the Early-est earthquake monitor at INGV-Rome (http://early-est.rm.ingv.it). We also show that the difference m b - log10( T d T 0) forms a rapid discriminant for slow, tsunami earthquakes. The rapid availability of these measurements can aid in faster and more reliable tsunami early warning for near to regional distances.

Lomax, Anthony; Michelini, Alberto

2013-09-01

331

TSUNAMI HAZARD ASSESSMENT IN THE NORTHERN AEGEAN SEA  

Directory of Open Access Journals (Sweden)

Full Text Available Emergency planning for the assessment of tsunami hazard inundation and of secondary effects of erosion and landslides, requires mapping that can help identify coastal areas that are potentially vulnerable. The present study reviews tsunami susceptibility mapping for coastal areas of Turkey and Greece in the Aegean Sea. Potential tsunami vulnerable locations were identified from LANDSAT ETM imageries, Shuttle Radar Topography Mission (SRTM, 2000) data and QuickBird imageries and from a GIS integrated spatial database. LANDSAT ETM and Digital Elevation Model (DEM) data derived by the SRTM-Mission were investigated to help detect traces of past flooding events. LANDSAT ETM imageries, merged with digitally processed and enhanced SRTM data, clearly indicate the areas that may be prone to flooding if catastrophic tsunami events or storm surges occur.

Barbara Theilen-Willige

2008-01-01

332

Floods and tsunamis.  

UK PubMed Central (United Kingdom)

Floods and tsunamis cause few severe injuries, but those injuries can overwhelm local areas, depending on the magnitude of the disaster. Most injuries are extremity fractures, lacerations, and sprains. Because of the mechanism of soft tissue and bone injuries, infection is a significant risk. Aspiration pneumonias are also associated with tsunamis. Appropriate precautionary interventions prevent communicable dis-ease outbreaks. Psychosocial health issues must be considered.

Llewellyn M

2006-06-01

333

Floods and tsunamis.  

Science.gov (United States)

Floods and tsunamis cause few severe injuries, but those injuries can overwhelm local areas, depending on the magnitude of the disaster. Most injuries are extremity fractures, lacerations, and sprains. Because of the mechanism of soft tissue and bone injuries, infection is a significant risk. Aspiration pneumonias are also associated with tsunamis. Appropriate precautionary interventions prevent communicable dis-ease outbreaks. Psychosocial health issues must be considered. PMID:16781270

Llewellyn, Mark

2006-06-01

334

Hydrodynamic modeling of tsunamis from the Currituck landslide  

Science.gov (United States)

Tsunami generation from the Currituck landslide offshore North Carolina and propagation of waves toward the U.S. coastline are modeled based on recent geotechnical analysis of slide movement. A long and intermediate wave modeling package (COULWAVE) based on the non-linear Boussinesq equations are used to simulate the tsunami. This model includes procedures to incorporate bottom friction, wave breaking, and overland flow during runup. Potential tsunamis generated from the Currituck landslide are analyzed using four approaches: (1) tsunami wave history is calculated from several different scenarios indicated by geotechnical stability and mobility analyses; (2) a sensitivity analysis is conducted to determine the effects of both landslide failure duration during generation and bottom friction along the continental shelf during propagation; (3) wave history is calculated over a regional area to determine the propagation of energy oblique to the slide axis; and (4) a high-resolution 1D model is developed to accurately model wave breaking and the combined influence of nonlinearity and dispersion during nearshore propagation and runup. The primary source parameter that affects tsunami severity for this case study is landslide volume, with failure duration having a secondary influence. Bottom friction during propagation across the continental shelf has a strong influence on the attenuation of the tsunami during propagation. The high-resolution 1D model also indicates that the tsunami undergoes nonlinear fission prior to wave breaking, generating independent, short-period waves. Wave breaking occurs approximately 40-50??km offshore where a tsunami bore is formed that persists during runup. These analyses illustrate the complex nature of landslide tsunamis, necessitating the use of detailed landslide stability/mobility models and higher-order hydrodynamic models to determine their hazard.

Geist, E. L.; Lynett, P. J.; Chaytor, J. D.

2009-01-01

335

Using Internet reports for early estimates of the final death toll of earthquake-generated tsunami: the March 11, 2011, Tohoku, Japan, earthquake  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A retrospective case study was conducted for the March 11, 2011, earthquake that occurred off the east Pacific coast of Tohoku, Japan, with reference to the Sumatra-Andaman earthquake and Indian Ocean tsunami on December 26, 2004. The regularities of the temporal variations of the number of deaths r...

Xiaolin Yang; Zhongliang Wu; Yingchun Li

336

The UBO-TSUFD tsunami inundation model: validation and application to a tsunami case study focused on the city of Catania, Italy  

Science.gov (United States)

Nowadays numerical models are a powerful tool in tsunami research since they can be used (i) to reconstruct modern and historical events, (ii) to cast new light on tsunami sources by inverting tsunami data and observations, (iii) to build scenarios in the frame of tsunami mitigation plans, and (iv) to produce forecasts of tsunami impact and inundation in systems of early warning. In parallel with the general recognition of the importance of numerical tsunami simulations, the demand has grown for reliable tsunami codes, validated through tests agreed upon by the tsunami community. This paper presents the tsunami code UBO-TSUFD that has been developed at the University of Bologna, Italy, and that solves the non-linear shallow water (NSW) equations in a Cartesian frame, with inclusion of bottom friction and exclusion of the Coriolis force, by means of a leapfrog (LF) finite-difference scheme on a staggered grid and that accounts for moving boundaries to compute sea inundation and withdrawal at the coast. Results of UBO-TSUFD applied to four classical benchmark problems are shown: two benchmarks are based on analytical solutions, one on a plane wave propagating on a flat channel with a constant slope beach; and one on a laboratory experiment. The code is proven to perform very satisfactorily since it reproduces quite well the benchmark theoretical and experimental data. Further, the code is applied to a realistic tsunami case: a scenario of a tsunami threatening the coasts of eastern Sicily, Italy, is defined and discussed based on the historical tsunami of 11 January 1693, i.e. one of the most severe events in the Italian history.

Tinti, S.; Tonini, R.

2013-07-01

337

The tectonic source of the 1755 Lisbon earthquake and tsunami  

Directory of Open Access Journals (Sweden)

Full Text Available The SW continental margin of Iberia is affected by several tectonic structures of Cenozoic to Recent age, gen-erated by the dynamics of the Iberia-Africa plate margin. This activity is testified by diffuse seismicity along the eastern portion of the Azores-Gibraltar line. The most important active structure, detected during a reflection seismic survey in 1992, is a thrust-fault, some 50 km long and with dip-slip throw of more than 1 km, located offshore Cabo de S. Vincente. A relocation of historical earthquakes in the area shows that this structure lies very close to the epicentre of the catastrophic 1755 Lisbon earthquake and that it should be the generator of the event. This submarine structure can now be studied for modelization of tsunamis and consequent risk mitigation.

N. Zitellini; F. Chierici; R. Sartori; L. Torelli

1999-01-01

338

WDC/National Geophysical Data Center 2004 Indian Ocean Tsunami Data  

Science.gov (United States)

The World Data Center (WDC) for Solid Earth Geophysics (including tsunamis) is operated by NOAA's National Geophysical Data Center (NGDC). NGDC is one of three environmental data centers within the National Environmental Satellite, Data and Information Service (NESDIS). Operating both World and National Data Centers, WDC/NGDC provides the long-term archive, data management, and access to national and global tsunami data for research and mitigation of tsunami hazards. Archive responsibilities include the global historical tsunami database, the bottom pressure recorder data, and access to event-specific tide-gauge data, as well as other related hazards and bathymetric data and information. The Global Historical Tsunami Database includes data for more than 1,700 events since 2,000 BC and more than 8,500 locations where tsunamis were observed. The tsunami database contains extensive information on the 2004 Indian Ocean tsunami including earthquake and tsunami effects and imagery. The associated tsunami runup database provides information on over 700 locations in 39 different countries, in three different oceans, where the tsunami was observed. The runup data records include information on the location where the wave was observed, arrival time, first motion of the wave, wave periods, distance from the tsunami source, maximum wave height, maximum inundation distance, and effects at the location such as deaths, injuries, and damage. Links are also provided to the tide gauge time- series data where available. All of the WDC/NGDC tsunami and natural hazards databases are stored in a relational database management system. These data are accessible over the Web as tables, reports, interactive maps, and custom CD-ROMs.

Stroker, K.; Dunbar, P.; Brocko, R.

2006-12-01

339

Geological identification of historical tsunamis in the Gulf of Corinth, Central Greece  

Directory of Open Access Journals (Sweden)

Full Text Available Geological identification of tsunami deposits is important for tsunami hazard studies, especially in areas where the historical data set is limited or absent. Evidence left by historical tsunamis in the coastal sedimentary record of the Gulf of Corinth was investigated by trenching and coring in Kirra on the north coast and Aliki on the south coast. The Gulf of Corinth has a documented tsunami history dating back to the 4th century BC. Comparison of the historical records and the results of stratigraphical, sedimentological and foraminiferal analyses show that extreme coastal flooding events are detectable in the coastal sequences. The geological record from Kirra shows four sand layers deposited by high-energy marine flooding events. The deposits identified show many similarities with tsunami deposits described elsewhere. The lower sand deposit (layer 4) was radiocarbon dated to 3020–2820 BC. Assuming an average sedimentation rate of 2.6 cm (100 yr)?1, the ages of the other three sand layers were estimated by extrapolation to the time windows 1200–1000 BC, AD 500–600 and AD 1400–1500. There are no historical tsunamis which correlate with layers 2 and 3. However, layer 1 may represent the major AD 1402 tsunami. Sand dykes penetrating from layer 1 into the overlying silts suggest soil liquefaction during an earthquake event, possibly the 1 August 1870 one. At Aliki, no clear stratigraphical evidence of tsunami flooding was found, but results from foraminiferal and dating analyses show that a sand layer was deposited about 180 years ago from a marine flooding event. This layer may be associated with the historical tsunami of 23 August 1817, which caused widespread destruction in the Aegion area. The work presented here supports the idea that geological methods can be used to extend tsunami history far beyond the historical record. Although the tsunami database obtained will be incomplete and biased towards larger events, it will still be useful for extreme event statistical approaches.

S. Kortekaas; G. A. Papadopoulos; A. Ganas; A. B. Cundy; A. Diakantoni

2011-01-01

340

The role of deposits in tsunami risk assessment  

Science.gov (United States)

An incomplete catalogue of tsunamis in the written record hinders tsunami risk assessment. Tsunami deposits, hard evidence of tsunami, can be used to extend the written record. The two primary factors in tsunami risk, tsunami frequency and magnitude, can be addressed through field and modeling studies of tsunami deposits. Recent research has increased the utility of tsunami deposits in tsunami risk assessment by improving the ability to identify tsunami deposits and developing models to determine tsunami magnitude from deposit characteristics. Copyright ASCE 2008.

Jaffe, B.

2008-01-01

 
 
 
 
341

Catalog of Tsunamis in Alaska.  

Science.gov (United States)

This summary of the history of tsunamis was prompted by the recent establishments of the Alaska Regional Tsunami Warning System to cope with the special problems of providing useful warnings of tsunamis along the coastlines of Alaska and the Aleutian Isla...

D. C. Cox G. Pararas-Carayannis

1969-01-01

342

Frequency Domain Response at Pacific Coast Harbors to Major Tsunamis of 2005-2011  

Science.gov (United States)

Tsunamis waves caused by submarine earthquake or landslide might contain large wave energy, which could cause significant human loss and property damage locally as well as in distant region. The response of three harbors located at the Pacific coast (i.e. Crescent City Harbor, Los Angeles/Long Beach Port, and San Diego Harbor) to six well-known tsunamis events generated (both near-field and far-field) between 2005 and 2011 are examined and simulated using a hybrid finite element numerical model in frequency domain. The model incorporated the effects of wave refraction, wave diffraction, partial wave reflection from boundaries, entrance and bottom energy dissipation. It can be applied to harbor regions with arbitrary shapes and variable water depth. The computed resonant periods or modes of oscillation for three harbors are in good agreement with the energy spectral analysis of the time series of water surface elevations recorded at tide gauge stations inside three harbors during the six tsunamis events. The computed wave induced currents based on the present model are also in qualitative agreement with some of the reported eye-witness accounts absence of reliable current data. The simulated results show that each harbor responded differently and significantly amplified certain wave period(s) of incident wave trains according to the shape, topography, characteristic dimensions and water depth of the harbor basins.

Xing, Xiuying; Kou, Zhiqing; Huang, Ziyi; Lee, Jiin-Jen

2013-06-01

343

Surviving a Tsunami: Lessons from Chile, Hawaii, and Japan  

Science.gov (United States)

This report contains true stories that illustrate how to survive (and how not to survive) a tsunami. It is meant for people who live, work, or play along coasts that tsunamis may strike. The stories are personal accounts selected from interviews with people who survived a Pacific Ocean tsunami generated by the magnitude 9.5 earthquake that occurred along the coast of Chile on May 22, 1960. Important points include the necessity to heed all warnings (official and natural), head for higher ground, expect many waves, and not to attempt to recover personal belongings.

344

MadGraph/MadEvent v4: The New Web Generation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We present the latest developments of the MadGraph/MadEvent Monte Carlo event generator and several applications to hadron collider physics. In the current version events at the parton, hadron and detector level can be generated directly from a web interface, for arbitrary processes in the Standard ...

Alwall, Johan; Plehn, Tilman; Rainwater, David L.; Stelzer, Tim; Demin, Pavel; de Visscher, Simon; Frederix, Rikkert

345

Modelling the tsunami free oscillations in the Marquesas (French Polynesia)  

Science.gov (United States)

The tsunami resonance inside basins (closed or semi-enclosed) depends on the period of the incident waves, reflection and energy dissipation, characteristics of the boundary and the geometry of the basin. When waves continuously enter the basin, they cause abnormal water level fluctuations and produced damage if their periods are close to the periods of free oscillation of the basin. These resonant oscillations inside harbours, bays, or other semi-enclosed or closed basins can have a direct influence on the management of harbours, shipping and coastal uses. So, it is important to determine these free oscillations. These resonant characteristics have been observed in the Marquesas, an archipelago prone to tsunami amplification, during the last three tsunamis (Samoa 2009, Maule 2010, Tohoku 2011). These events were recorded by the two tide gauges located in the Marquesas. In this archipelago, there are two monitored bays : the first one is located in Hiva Oa Island (Tahauku Bay) and the second in Nuku Hiva Island (Taihoae Bay). For all these tsunamis, more than 3 d of water tidal resonance were recorded. In this work, we make a free oscillation analysis of the Marquesas Archipelago using real tide gauge data, simulated tsunami data and theoretical computations. During the last century, this archipelago was hit by several trans-Pacific tsunamis. It is interesting to note that, following different tsunami reports the bays responded differently depending on the earthquake source region. For example, Tahauku and Atuona, two bays in Hiva Oa Island only 1 km apart, have different responses depending on the tsunami, as it was observed in 1946 (Aleutian earthquake) and 1960 (Chile earthquake). For this reason, we study the azimuthal dependence of the excitation of the free oscillation modes, and we show that some azimuths enhance tsunami amplification.

Allgeyer, S.; Hébert, H.; Madariaga, R.

2013-06-01

346

Plasmon tsunamis on metallic nanoclusters  

International Nuclear Information System (INIS)

A model is constructed to describe inelastic scattering events accompanying electron capture by a highly charged ion flying by a metallic nanosphere. The electronic energy liberated by an electron leaving the Fermi level of the metal and dropping into a deep Rydberg state of the ion is used to increase the ion kinetic energy and, simultaneously, to excite multiple surface plasmons around the positively charged hole left behind on the metal sphere. This tsunami-like phenomenon manifests itself as periodic oscillations in the kinetic energy gain spectrum of the ion. The theory developed here extends our previous treatment (Lucas et al 2011 New J. Phys. 13 013034) of the Arq+/C60 charge exchange system. We provide an analysis of how the individual multipolar surface plasmons of the metallic sphere contribute to the formation of the oscillatory gain spectrum. Gain spectra showing characteristic, tsunami-like oscillations are simulated for Ar15+ ions capturing one electron in distant collisions with Al and Na nanoclusters. (paper)

2012-03-14

347

Plasmon tsunamis on metallic nanoclusters.  

Science.gov (United States)

A model is constructed to describe inelastic scattering events accompanying electron capture by a highly charged ion flying by a metallic nanosphere. The electronic energy liberated by an electron leaving the Fermi level of the metal and dropping into a deep Rydberg state of the ion is used to increase the ion kinetic energy and, simultaneously, to excite multiple surface plasmons around the positively charged hole left behind on the metal sphere. This tsunami-like phenomenon manifests itself as periodic oscillations in the kinetic energy gain spectrum of the ion. The theory developed here extends our previous treatment (Lucas et al 2011 New J. Phys. 13 013034) of the Ar(q+)/C(60) charge exchange system. We provide an analysis of how the individual multipolar surface plasmons of the metallic sphere contribute to the formation of the oscillatory gain spectrum. Gain spectra showing characteristic, tsunami-like oscillations are simulated for Ar(15+) ions capturing one electron in distant collisions with Al and Na nanoclusters. PMID:22353847

Lucas, A A; Sunjic, M

2012-02-21

348

THE MOMENTUM OF TSUNAMI WAVES  

Directory of Open Access Journals (Sweden)

Full Text Available In the generation and propagation of tsunamis, it seemed like the momentum might be a quantity of some usefulness. In many tsunami generating situations the source mechanism might impart significant initial velocity to the water in addition to surface displacement. In the cases of pyroclastic flow and landslides from land into the water this is surely the case. The property of momentum that is especially noteworthy is that, unlike energy, the momentum of a body of water is affected only by external forces and not by internal forces associated with turbulence or laminar flow. These latter aspects of wave propagation dissipate energy and have disappeared from the distant wave motions in which principally irrotational flow remains. The impulse, Fdt, where F are external forces on the body of water, result in a change of momentum, d(Mv) of the body of water. The momentum density of a column of water of dimensions dxdy and from the bottom to the surface corresponding to particle velocities v(z) is the quantity discussed in this paper.

Harold G. Loomis

2002-01-01

349

Forecasting Wave Amplitudes after the Arrival of a Tsunami  

Science.gov (United States)

The destructive Pacific Ocean tsunami generated off the east coast of Honshu, Japan, on 11 March 2011 prompted the West Coast and Alaska Tsunami Warning Center (WCATWC) to issue a tsunami warning and advisory for the coastal regions of Alaska, British Columbia, Washington, Oregon, and California. Estimating the length of time the warning or advisory would remain in effect proved difficult. To address this problem, the WCATWC developed a technique to estimate the amplitude decay of a tsunami recorded at tide stations within the Warning Center's Area of Responsibly (AOR). At many sites along the West Coast of North America, the tsunami wave amplitudes will decay exponentially following the arrival of the maximum wave (uc(Mofjeld) et al., Nat Hazards 22:71-89, 2000). To estimate the time it will take before wave amplitudes drop to safe levels, the real-time tide gauge data are filtered to remove the effects of tidal variations. The analytic envelope is computed and a 2 h sequence of amplitude values following the tsunami peak is used to obtain a least squares fit to an exponential function. This yields a decay curve which is then combined with an average West Coast decay function to provide an initial tsunami amplitude-duration forecast. This information may then be provided to emergency managers to assist with response planning.

Nyland, David; Huang, Paul

2013-08-01

350

May Gravity detect Tsunami ?  

CERN Document Server

The present gravitational wave detectors are reaching lowest metric deviation fields able to detect galactic and extra-galactic gravitational waves, related to Supernova explosions up to Virgo cluster. The same gravitational wave detector are nevertheless almost able to reveal near field gravitational perturbations due to fast huge mass displacements as the ones occurring during largest Earth-Quake or Tsunami as the last on 26th December 2004 in Asiatic area. The prompt gravitational near field deformation by the Tsunami may reach the LIGO threshold sensitivity within 3000-10000 km distances. Their eventual discover (in LIGO data or in future on-line detector arrays) may offer the most rapid warning alarm system on earth. Nevertheless the later continental mass rearrangement and their gravitational field assessment on Earth must induce, for Richter Magnitude 9 Tsunami, a different terrestrial inertia momentum and a different rotation axis, as well as a detectable shrinking of the Earth radius of nearly R =1.7...

Fargion, D

2004-01-01

351

Alternative tsunami models  

International Nuclear Information System (INIS)

The interesting papers by Margaritondo (2005 Eur. J. Phys. 26 401) and by Helene and Yamashita (2006 Eur. J. Phys. 27 855) analysed the great Indian Ocean tsunami of 2004 using a simple one-dimensional canal wave model, which was appropriate for undergraduate students in physics and related fields of discipline. In this paper, two additional, easily understandable models, suitable for the same level of readership, are proposed: one, a two-dimensional model in flat space, and two, the same on a spherical surface. The models are used to study the tsunami produced by the central Kuril earthquake of November 2006. It is shown that the two alternative models, especially the latter one, give better representations of the wave amplitude, especially at far-flung locations. The latter model further demonstrates the enhancing effect on the amplitude due to the curvature of the Earth for far-reaching tsunami propagation.

2009-01-01

352

Modeling of Sedimentary Bedforms Produced by Impact-induced Tsunami in the ~2.6 GA Hamersley Basin, Western Australia  

Science.gov (United States)

The late Archean Wittenoom Formation (Hamersley Basin, Western Australia) contains a widespread sedimentary layer containing sand-sized spherules interpreted by Simonson as microkrystites. In the western Hamersley Basin, the spherules form a distinct layer of wave-formed an-orbital ripples with an average length and height of 53 cm and 1 cm. The ripples are the only wave-formed features in Hamersley Basin strata for hundreds of meters strati- graphically and hundreds of kilometers in any direction laterally; they record an exceedingly rare sedimentation event. Since the layer consists almost exclusively of microkrystites, we hypothesize that it was formed by impact-induced tsunami very shortly after initial deposition from the impact, with minimal time for background sediments to accumulate. We have tested this hypothesis through mathematical modeling of both the propagation of impact-generated tsunami into the Hamersley Basin and the sedimentary structures they are capable of producing. To allow this modeling, we have calculated bolide diameter, crater size, and the distance between the target area and the Hamersley Basin using equations developed by other workers. We have also assumed a simple basin model involving impact in the deep ocean and tsunami propagation into the relatively shallow Hamersley Basin. Our results indicate that tsunami were of appropriate height and period to produce the bedforms observed in the Hamersley Basin.

Hassler, S. W.; Robey, H. F.; Davies, D.; Simonson, B.

1996-03-01

353

Towards Tsunami Hazard Assessment for the Coasts of Italy  

Science.gov (United States)

A reliable Probabilistic Tsunami Hazard Assessment (PTHA) requires an enormous computational effort. We are developing an approach for limiting the computational burden while trying to preserve the variability of the tsunamigenic seismic sources. We split the PTHA into two stages: linear PTHA and nonlinear PTHA. In the first stage, we explore a large variety of seismic sources, representing the most likely complete set of potential sources, and estimate the tsunami propagation in the linear approximation for all the considered target coastlines. We then sample the most hazardous sub-regions of the source parameters/target sites space, by assuming zero probability of hazard threshold exceedance for the remainder. With this subset, which forms the basis for the second stage, we generate probabilistic inundation maps for several damage metrics. We present preliminary results of PTHA for the coasts of Italy. To take into account the different levels of knowledge of potential earthquake sources in different areas of the Mediterranean Sea, we define a logic tree that mainly represents the uncertainties related to seismic source existence. We then use an event tree approach for describing the variability of earthquake parameters.

Lorito, S.; Romano, F.; Piatanesi, A.; Basili, R.; Kastelic, V.; Tiberti, M.; Valensise, G.; Selva, J.

2011-12-01

354

Rapid forecasting of tsunami runup heights from 2-D numerical simulations  

Directory of Open Access Journals (Sweden)

Full Text Available We propose a method to compute tsunami runup heights that is based on an integration of numerical, 2-D shallow-water modelling and an analytical, 1-D long-wave runup theory. This approach provides a faster forecast of tsunami runup heights than a complicated coastal inundation model. Through simulations of potential tsunami scenarios, this approach can also be applied to long-term tsunami prediction. We tested the model by simulating the historical event in the East (Japan) Sea and found that the estimates of runup heights agreed well with the available observations.

B. H. Choi; V. Kaistrenko; K. O. Kim; B. I. Min; E. Pelinovsky

2011-01-01

355

USING A SATELLITE TELEPHONE TO RETRIEVE TSUNAMI DATA FROM TIDE SITES IN THE PACIFIC BASIN  

Directory of Open Access Journals (Sweden)

Full Text Available The tsunami warning centers require accurate, timely and reliable tide data during a large potentially tsunamigenic earthquake. At the present time tide gauge data in remote parts of the Pacific Basin are often not availableto view during a potential tsunami event or the data may be transmitted hours after the expected tsunami arrival time. This delay can adversely affect state and local emergency officials who require lead times for placing their areas in awarning status.The West Coast/Alaska Tsunami Warning Center conduct eda feasibility study, which showed that a satellite telephone link can be used to collect tide gauge data from remote sites in a timely manner.

G.W. Urban; A.H. Medbery; T.J.Sokolowski

2001-01-01

356

The 25 October 2010 Mentawai tsunami earthquake, from real-time discriminants, finite-fault rupture, and tsunami excitation  

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The moment magnitude 7.8 earthquake that struck offshore the Mentawai islands in western Indonesia on 25 October 2010 created a locally large tsunami that caused more than 400 human causalities. We identify this earthquake as a rare slow-source tsunami earthquake based on: 1) disproportionately large tsunami waves; 2) excessive rupture duration near 125 s; 3) predominantly shallow, near-trench slip determined through finite-fault modeling; and 4) deficiencies in energy-to-moment and energy-to-duration-cubed ratios, the latter in near-real time. We detail the real-time solutions that identified the slow-nature of this event, and evaluate how regional reductions in crustal rigidity along the shallow trench as determined by reduced rupture velocity contributed to increased slip, causing the 5–9 m local tsunami runup and observed transoceanic wave heights observed 1600 km to the southeast.

Newman, Andrew V.; Hayes, Gavin; Wei, Yong; Convers, Jaime

2011-01-01

357

Earthquakes and Tsunamis  

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In this activity, by the Lane Community College MAPS GIS Program, students work in teams to evaluate Oregon citiesâ tsunami evacuation plans related to a potential 8.1 coastal earthquake. Teams use additional information from a Web-based GIS to study the multi-faceted nature of earthquake damage in addition to tsunami impacts and make recommendations to improve the existing plan. The data are from the Oregon Geospatial Data Clearinghouse and the Oregon Department of Geology and Mines. On this site, visitors will find both the teacher version of the lesson plan and the student exercise, both as PDFs.

2008-08-13

358

Comparison of the 2010 Chile and 2011 Japan Tsunamis in the Far Field  

Science.gov (United States)

In this study we analyze water level data from coastal tide gauges and deep-ocean tsunameters to explore the far-field characteristics of two major trans-Pacific tsunamis, the 2010 Chile and the 2011 Japan (Tohoku-oki) events. We focused our attention on data recorded in California (14 stations) and New Zealand (31 stations) as well as on tsunameters situated along the tsunami path and proximal to the study sites. Our analysis considers statistical analyses of the time series to determine arrival times of the tsunami as well as the timing of the largest waves and the highest absolute sea levels. Fourier and wavelet analysis were used to describe the spectral content of the tsunami signal. These characteristics were then compared between the two events to highlight similarities and differences between the signals as a function of the receiving environment and the tsunami source. This study provides a comprehensive analysis of far-field tsunami characteristics in the Pacific Ocean, which has not experienced a major tsunami in nearly 50 years. As such, it systematically describes the tsunami response characteristics of modern maritime infrastructure in New Zealand and California and will be of value for future tsunami hazard assessments in both countries.

Borrero, Jose C.; Greer, S. Dougal

2013-06-01

359

Analysis and modelling of tsunami-induced tilt for the 2007, M = 7.6, Tocopilla and the 2010, M = 8.8 Maule earthquakes, Chile, from long-base tiltmeter and broadband seismometer records  

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We present a detailed study of tsunami-induced tilt at in-land sites, to test the interest and feasibility of such analysis for tsunami detection and modelling. We studied tiltmeter and broadband seismometer records of northern Chile, detecting a clear signature of the tsunamis generated by the 2007 Tocopilla (M = 7.6) and the 2010 Maule (M = 8.8) earthquakes. We find that these records are dominated by the tilt due to the elastic loading of the oceanic floor, with a small effect of the horizontal gravitational attraction. We modelled the Maule tsunami using the seismic source model proposed by Delouis et al. and a bathymetric map, correctly fitting three tide gauge records of the area (Antofagasta, Iquique and Arica). At all the closest stations (7 STS2, 2 long-base tiltmeters), we correctly modelled the first few hours of the tilt signal for the Maule tsunami. The only phase mismatch is for the site that is closer to the ocean. We find a tilt response of 0.005-0.01 ?m at 7 km away from the coastline in response to a sea level amplitude change of 10 cm. For the Maule earthquake, we observe a clear tilt signal starting 20 min before the arrival time of the tsunami at the nearest point on the coastline. This capability of tilt or seismic sensors to detect distant tsunamis before they arrive has been successfully tested with a scenario megathrust in the southern Peru-northern Chile seismic gap. However, for large events near the stations, this analysis may no longer be feasible, due to the large amplitude of the long-period seismic signals expected to obscure the loading signal. Inland tilt measurements of tsunamis smooth out short, often unmodelled wavelengths of the sea level perturbation, thus providing robust, large-scale images of the tsunami. Furthermore, tilt measurements are not expected to saturate even for the largest run-ups, nor to suffer from near-coast tsunami damages. Tiltmeters and broadband seismometers are thus valuable instruments for monitoring tsunamis in complement with tide gauge arrays.

Boudin, F.; Allgeyer, S.; Bernard, P.; Hébert, H.; Olcay, M.; Madariaga, R.; El-Madani, M.; Vilotte, J.-P.; Peyrat, S.; Nercessian, A.; Schurr, B.; Esnoult, M.-F.; Asch, G.; Nunez, I.; Kammenthaler, M.

2013-07-01

360

India's archive of past massive erosional events  

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The 2004 Indian Ocean Tsunami event devastated a number of major coastal regions in South Asia, including the Tamil Nadu coast of India. In many areas on the east coast of India, distinct deposits of tsunami sands drape the landscape and overlie the muddy deposits of the coastal plain. Using erosional, as well as depositional features of the 2004 tsunami as proxy for past events, we present new subsurface evidence of past erosional events along the south-east coast of India.

Nair, R. R.

2009-12-01