Tsunami Research Research Papers - Academia.edu (original) (raw)

The May 22nd 1960 Chilean earthquake was the largest earthquake on record with a magnitude 9.5. The event caused extensive subsidence and uplift over wide areas (at least 130,000 km2) with uplift on the offshore South American Plate margin and downwarping in the coastal and landward areas which ranged in magnitude from 1–2 m. The subsidence deepened coastal rivers creating extensive shallow banks (now wetlands) in many rivers including the Río Cruces. The amount of subsidence was well-documented with field measurements recorded soon after the event. This study using sediment accumulation histories predicts the recovery timeof the Río Cruces to pre-1960 conditions, an important factor for assessing the fidelity of seismic recorders in the geological record. Sediment cores (n=139) from the subtidal areas of the Río Cruces were lithologically logged and selectively analyzed using high-resolution particle-size distribution (PSD) plots, microfossil analysis (thecamoebians) and 210Pb, 137Cs dating, documenting the post-1960 thickness of sediment. The analysis differentiated four main facies which include: 1) Floodplain Soil Horizon, 2) Tsunami or Flood Unit, 3) Post-Earthquake Adjustment, and 4) River Sedimentation. The post-1960 river sediment is clearly demarcated in the cores by highly-peaked PSDs (4–5 phi), abundant thecamoebian tests and high diversities compared to the underlying facies. Species compositions are typical of lacustrine or slow-moving river systems (Cucurbitella tricuspis, Difflugia oblonga, Centropyxis constricta, Centropyxis aculeata, Lagenodifflugia vas, and Difflugia protaeiformis). Based on this core data, the shallow banks along the Río Cruces will likely shoal in less than 100 yrs (<50 yrs from present). Between 1960 and 2008 thewater depths of the shallowbankswere reduced by more than half, to an averagewater depth of less than 1 m due to 60 to 80 cm (1.25–1.68 cm/yr) of sedimentation over that period. Time estimates for recovery to a floodplain are estimated to be in the 100–200 yr range due to uncertainty in compaction rates of the organic rich sediment. These estimated recovery times in a microtidal setting (<1 m) are longer than those measured in themacrotidal (∼9 m) setting of Portage, Alaska (10–20 yrs) andmore similar to the estimated rates of 100–150 yrs for the mesotidal (∼3 m) Willapa Bay, Washington at the Cascadia subduction zone. Based on these estimates, the submerged mid-lower reaches of the Río Cruces are at the limit of being a good seismic recorder and it is possible that this settingwould under represent large events if
they had recurrence intervals less than several centuries.

- by
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- Sedimentology, Coastal Processes, Tectonics & Sedimentation, Tsunami Research
- by Diana Contreras
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- Sentiment Analysis, Social Media, Twitter, Tsunami

Tsunamis are one of the most destructive natural hazards that affect the coastal areas. Tsunami waves that impact the coast with enormous energy are capable of destroying the objects on the coast and re-shaping the coastal geography, geomorphology and ecosystem. These waves can also cause extensive damage and disruption to human lives, their livelihood, infrastructure and economic activities.
The 26 December 2004 Sumatra-Andaman earthquake, one of the largest recorded and deadliest tremor, created an unparalleled catastrophic
tsunami wiping out thousands of human lives and throwing millions homeless. This event attracted the interest of several geoscientists in India and stimulated extensive scientific research. This article summarizes the tsunami related research work carried out in India during the past four years.

- by Uma Devi E and +1
- •
- Tsunami Research

The draft paper as at 24th April which is updated from the draft made for the oral presentation session (5th April 2017 does not contain any references and text errors needed corrections). The paper is still being worked on with more sections being added with some aspect areas clarified in more detail. Others are being reviewed. Due to the closure of the Parliament in the UK early for the snap elections, the text is still unfinished and will be resumed for the new Parliament session with no end date set yet. The document is best viewed by a download to Microsoft Word as web browsers tend to muddle the layout. Please note that the ice sheet mass balance changes occur mainly in nearby Iceland, Jan Mayen and the Mid-Atlantic Ridge rather than Greenland itself. (High viscous, low nucleation events pushing very cool, effusive, almost 'solid' lava incursions vertically up like the Mascarene volcanism of Mauritius are rare anomalies from a misaligned hotspot influencing further afield - and therefore far less likely.)

- by Veli Albert Kallio
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- Nuclear Engineering, Russian Studies, Glaciology, International Relations

The Italian Tsunami Alert Centre of the Istituto Nazionale di Geofisica e Vulcanologia (Centro di Allerta Tsunami, hereinafter CAT-INGV) supported a computer-assisted telephone interview (CATI) survey to investigate tsunami risk perception in two pilot regions of southern Italy. The survey was carried out on a stratified sample of 1021 interviewees representing about 3.2 million people living in 183 coastal municipalities of the two regions, namely Cal-abria and Apulia. The main goal of this research is to verify whether and how people's perception of tsunami hazard compares to the results of (PTHA)-probabilistic tsunami hazard assessment (TSUMAPS-NEAM project; Basili et al., 2018). As shown by the results of this project, both investigated regions are characterised by high tsunami hazard. Nonetheless, the long return time of such events could lead people to consider the occurrence of a tsunami in the Mediterranean Sea to be very unlikely. The survey results reveal that people's risk perception is low: for almost half of the whole sample the occurrence of a tsunami in the Mediterranean Sea is considered quite unlikely , with a clear difference between Apulia and Calabria. In the latter region the risk perception is much higher than in the former, probably due to the shorter time elapsed since the last event. Also, belonging to different coastal areas 1 appears to have a significant influence on the way tsunami haz-1 For the purposes of this paper, the term "coastal area" refers to the part of the coastline defined by both seas and regions' limits, according to current geographical conventions. Tyrrhenian Calabria indicates the coastal region between the municipalities of Tortora and Scilla, Ionian Calabria spans from Reggio Calabria to Rocca Imperiale; Ionian Apulia from Ginosa to Castrignano del Capo, and Adriatic Apulia from Gagliano del Capo to Chieuti. ard is conceived, having a stronger effect on risk character-isation: the interviewees of Tyrrhenian Calabria are indeed more likely to associate tsunami risk with volcanoes than the Ionian citizens. This is coherent considering the presence of active volcanoes and related tsunami precedents in the Tyrrhenian. Television emerged as the most relevant source of knowledge for almost 90 % of the sample, and the influence of media also results in the way tsunami risk is characterised. In particular, the survey showed that people's perception and understanding of tsunamis are affected by media accounts of large events, such as the 2004 Sumatra and the 2011 Japan tsunamis. At the same time, it is evident that the risk posed by smaller events is underrated. Furthermore, the survey's results show that the word "tsunami" occupies a different semantic space in comparison to the Italian traditional head-word maremoto, with differences among sample strata. In other words, the same physical phenomenon would be understood in two different ways by younger, educated people and elders with a low education level. The results of this study, although limited to two regions, provide a first assessment of tsunami risk perception in Italy, also entailing important consequences for both risk communication practice and mit-igation policies.

- by Andrea Cerase and +1
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- Sociology of Disaster, Disaster Studies, Disaster risk management, Natural Hazards
- by Raphaël Paris and +1
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- Psychology, Earth Sciences, Natural Hazards, Tsunami

It so happened that the beginning of work on paper: The mega-tsunami of 365 AD was the only unique cause of the enormous geological transformation of the Dead Sea area, the ruthless destruction of the cities of Sodom, Gomorrah, and more than 100 small settlements, a fairly large area of the eastern Mediterranean was studied. And the first decision, after a preliminary analysis, was to combine the study of the Dead Sea and Arabia. The main reason for this was two facts. The first was based on three scientific videos:What happened on July 21, 365 A.D.?,

- by Pazynych Wasyl
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- Oceanography, Tsunami impact, Tsunami Research

Author Contributions: S.P. designed the study. S.W. led the landslide and tsunami modelling, while H.S. and A.S. prepared samples and shepherded radiometric dating. G.C. conducted the analysis of biota. F.M., F.B., and M.Ray. assisted in ideation of the study and M.Rod. facilitated field logistics. A.A. organized the expedition and led site selection.

- by Arash Sharifi
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- Coastal Hazards, Red Sea, Tsunami Research

Tsunamis are one of the most destructive natural hazards that affect the coastal areas. Tsunami waves that impact the coast with enormous energy are capable of destroying the objects on the coast and re-shaping the coastal geography, geomorphology and ecosystem. These waves can also cause extensive damage and disruption to human lives, their livelihood, infrastructure and economic activities. The 26 December 2004 Sumatra-Andaman earthquake, one of the largest recorded and deadliest tremor, created an unparalleled catastrophic tsunami wiping out thousands of human lives and throwing millions homeless. This event attracted the interest of several geoscientists in India and stimulated extensive scientific research. This article summarizes the tsunami related research work carried out in India during the past four years.

- by Uma Devi E and +1
- •
- Tsunami Research

My draft notes for the Environmental Audit Committee's oral discussions on 5th April 2017 at the Houses of Parliament without references given here. The oral session draft was published on 28th April 2017 with the final text still in reviews to include important additional items omitted on the draft text. The full text will have soon all the necessary references. Due to this text being a draft the text and images appear unaligned with the text due to it being draft for the session on 5th April. However, the Parliament decided nevertheless to publish this semi-complete version. More up-to-date text (.docx format) is on Drafts section. It has been receiving reviews and I will publish the final text separately once all the external input has been duly received and processed.

- by Veli Albert Kallio
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- Nuclear Engineering, Canadian Studies, Glaciology, Coastal Management

In the wake of the devastating 2011 Tōhoku earthquake and tsunami, the Central Disaster Management Council of the Japanese Cabinet Office issued new guidance for assessing seismic hazards in Japan. Following the unexpectedly large magnitude of the earthquake and the size of the tsunami, the Cabinet Office advocated renewed investigation of earthquake and tsunami occurrence timescales exceeding the historical period, with a particular focus on defining the largest possible magnitudes. The new guidelines pay close attention to the Nankai Trough, the subduction zone where the Philippine Sea Plate dives beneath the Eurasian Plate. The Nankai Trough faces the densely populated and highly industrialised coastline of south central Japan. Here, we review geological evidence for past earthquakes and tsunamis along this subduction zone. This evidence comes from a wide variety of sources, including uplifted marine terraces, turbidites, liquefaction features, subsided marshes and tsunami deposits in coastal lakes and lowlands. More than 70 sites yield evidence, however the number of events recorded at each site varies depending on site-specific evidence creation and preservation thresholds. The longest record exceeds ten thousand years, however the majority are less than four thousand years long. Our compilation suggests that earthquakes in AD 684 and 1361 were similar predecessors of the AD 1707 earthquake, widely regarded as the largest event of the historical period. The more limited distribution of evidence for other historical earthquakes highlights the variability in rupture mode that characterises the Nankai Trough. The palaeoseismic catalogue is, however, limited due to issues over alternative hypotheses for proposed palaeoseismic evidence, poor chronological control and sampling approached insufficient to address the recurrence of the largest past earthquakes and tsunamis. We highlight recent advances and propose future directions for Nankai Trough palaeoseismology.

The Italian Tsunami Warning Centre (Centro Allerta Tsunami, CAT) of Istituto Nazionale di Geofisica e Vulcanologia (INGV) operates to issue tsunami alert messages both to the Italian Civil Protection system and to several countries of the Mediterranean. CAT-INGV started its activities as a candidate tsunami service provider in the framework of the ICG/NEAMTWS of IOC-UNESCO in 2013, to become operational in 2016. At national level, it operates since 2017 following the “SiAM” Prime Minister Directive, under the coordination of the Italian Civil Protection Department and together with ISPRA. In this paper we discuss the responsibilities of the CAT-INGV operators in the light of the Italian legal system, describing which are the critical aspects of the surveillance and issuance of the alerting messages, and trying to delineate the tools useful to limit legal problems for the operators in case of damaging events or false alarms.

- by Andrea Cerase and +1
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- Disaster risk management, Risk Governance, Risk regulation, Crisis Communication

RESUMEN Se identificó y evaluó la vulnerabilidad de un total de 227 edificaciones asociadas al turismo en la ciudad puerto de Valparaíso, que se encuentran en el área de inundación definida para el peor escenario conocido para la zona. Se utilizó el Modelo de Evaluación de la Vulnerabilidad por Tsunami de Papathoma (PTVA-3). Los resultados muestran que las edificaciones asociadas al alojamiento, como hoteles, presentan bajos índices de vulnerabilidad, por lo que se recomienda considerar la evacuación vertical en estos casos. Las otras tipologías-alimentación, atractivos y servicios-también presentan en general bajos índices de vulnerabilidad, pero con mayor dispersión. El puerto y la línea ferroviaria se han transformado en una barrera de protección y exclusión de emplazamientos de edificaciones en las zonas más expuestas. En los sectores emplazados entre la línea férrea y la línea costera, tales como Caleta Portales y Muelle Barón, se concentran las edificaciones con mayor índice de vulnerabilidad. PALABRAS CLAVE Evaluación vulnerabilidad por tsunami de Papathoma, PTVA-3, Vulnerabilidad urbana de edificaciones, Área de inundación TSUNAMI VULNERABILITY ASSESSMENT FOR THE TOURISM SECTOR IN VALPARAÍSO, CHILE ABSTRACT The vulnerability of a total of 227 buildings associated with tourism in the port city of Valparaíso, which is located in the flood area defined for the worst known scenario for the area, was identified and evaluated. The Papathoma Tsunami Vulnerability Assessment Model (PTVA-3) was used. The results show that the buildings were associated with accommodation, have low vulnerability indexes, it is recommended to consider vertical evacuation in these cases. The other typologies-restaurant, sight and services-also have low vulnerability indexes, but with greater dispersion. The port and the railway line have been transformed into a barrier of protection and exclusion of building sites in the most exposed areas. Sectors that remain outside the railway line, such as Caleta Portales and Muelle Barón, show the highest vulnerabilities.

In the wake of the devastating 2011 To ̄hoku earthquake and tsunami, the Central Disaster Management Council of the Japanese Cabinet Office issued new guidance for assessing seismic hazards in Japan. Before 2011, seismic hazard assessment relied on source models developed from knowledge of a small number of well-documented historical earthquakes. Less well-known historical earthquakes, including the AD 869 Jo ̄gan Sanriku earthquake, were largely disregarded as their seismic intensities or tsunami heights could not be reconciled with the chosen seismic sources. Following the unexpectedly large size of the To ̄hoku earthquake, the Cabinet Office advocated renewed investigation of earthquake and tsunami occurrence over historical and longer timescales, with a particular focus on defining the largest possible magnitudes. The new guidelines pay close attention to the Nankai Trough, the subduction zone where the Philippine Sea Plate dives beneath the Eurasian Plate. The Nankai Trough faces the densely populated and highly industrialised coastline of south central Japan and harbours a widely-known seismic gap along its eastern To ̄kai segment. A full-length rupture of the Nankai Trough, including the To ̄kai segment, could produce an earthquake with a magnitude approaching that of the 2011 event, with tsunami travel times to the closest shorelines of less than 30 minutes. We review geological evidence for historical and older earthquakes and tsunamis along the Nankai Trough. This evidence comes from a wide variety of sources, including uplifted marine terraces, subsided marshes, liquefaction features, turbidites and tsunami deposits in coastal lakes and low- lands. Examining papers published before and after 2011, we investigate the impact of the new Cabinet Office guidelines on attempts to understand the magnitude and recurrence of these events. Additionally, we introduce the Belgian Science Policy Office funded QuakeRecNankai project, a collaboration aiming to supplement existing records by generating a long time series of earthquake and tsunami recurrence from sites at the eastern end of the Nankai Trough. The project uses a diverse range of geophysical, sedimentological, geochemical and microfossil approaches to investigate records of Holocene paleotsunamis in and around Lake Hamana and records of seismic shaking from the Fuji Five Lakes.

- by Philip Garrett
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- Japanese Studies, Japanese History, Tsunami, Interdisciplinary History

A minor tsunami of about 50 cm was generated along
the coast of Qurayat near Makran subduction zone in
the Arabian Sea due to the 24 September 2013 Pakistan
earthquake of magnitude 7.6 Mw(mB), although its
source was ~200 km far inland of the Makran trench.
The real-time sea-level observation network in the
Arabian Sea recorded minor tsunami arrivals. In an
attempt to explain the mechanism of this unusual tsunami,
we use backward ray tracing technique to map
the admissible region of tsunamigenic source. Basically,
in this technique the ray equations are integrated
starting from the specific locations of tsunami
observations, in all possible directions. The known
travel time of the initial waves to the respective tide
gauges and tsunami buoys is used in this method.
Backward wave front is constructed by joining all
end-points of the rays from each of the locations. The
region where the envelope of all backward wave fronts
converges is considered as the source of the tsunami,
which is ~470 km from the earthquake epicentre with
the location at 24.8 N and 61.5 E. The admissible region
identified is an undersea section between Chabahar
and Gwadar, where a mud island had appeared
subsequent to this earthquake. Convergence of the
tsunami source zone and location of the mud island
suggest that the sudden uplift must have caused the
tsunami.

- by Uma Devi E
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- Tsunami Research

- by Pazynych Wasyl
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- Saudi Arabia, Romani Studies, Tsunami impact, Tsunami Research
- by Diana Contreras
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- Earth Sciences, Natural Language Processing, Social Media, Twitter

At 07:00 h (UTC-6) on 22 June 1932, a Ms =6.9
earthquake shocked the coasts of Colima and Jalisco. Five
minutes later a tsunami arrived at the coast. It almost completely
destroyed the town of Cuyutl´an, Colima, causing the
deaths of 50 people and leaving about 1200 injured. In this
study, newspaper reports and technical reports are reviewed,
as well as survivors’ testimonials. The physical characteristics
(mean sea level at the time, time of arrival, sea retreat,
and inundation distribution) and the tsunami effects (number
of victims, injuries, affected buildings) have been reconstructed
and mapped. The interpretation of historical data
allowed us to determine the intensity of the tsunami and to
reveal the tsunamigenic source. This study emphasizes the
relevance of historical analysis, including survivor’s testimonies,
in the reconstruction of tsunamis that lack instrumental
data. The results of this study are relevant to paleotsunami
studies and tsunami related hazard planning.

- by Nestor Corona
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- Tsunami Research

Southeast Asia has had both volcanic tsunamis and possesses some of the most densely populated, economically important and rapidly developing coastlines in the world. This contribution provides a review of volcanic tsunami hazard in Southeast Asia. Source mechanisms of tsunami related to eruptive and gravitational processes are presented, together with a history of past events in the region. A review of available data shows that many volcanoes are potentially tsunamigenic and present often neglected hazard to the rapidly developing coasts of the region. We highlight crucial volcanic provinces in Indonesia, the Philippines and Papua New Guinea and propose strategies for facing future events.

- by Martina Ulvrova and +2
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- Earth Sciences, Tsunami, Tsunamis, Tsunami Hazard

According to a deep-rooted conviction, the occurrence of a tsunami in the Mediterranean Sea would bevery rare. Unfortunately, this belief is definitely false: at least 2,000 of the 80,000 victims of the great earthquakein Messina (1908) were due to the tsunami that followed earthquake (Boschi et al. 1995). In 1956, a 7.7 magnitudecearthquake close to the Cycladic island of Amorgos (Greece) triggered large waves that also hit coasts of Amorgos, Astypalaia and Folegandros, with run-up values of 30, 20, and 10 mt (Okal et al., 2009). More recently, in 2003 a relatively small tsunami caused by a 6.9 magnitude earthquake in Boumerdes (Algeria) hit the Western Mediterranean coast causing damage properties in at least eight harbours in Balearic Islands (Velaet al. 2011) and two little tsunamis occurred in Dodecanese respectively in 2016 and 2017. Such events, that are just a little part of the over 290 historically known events occurred in the Mediterranean (Maramai, Brizuela & Graziani, 2014) should remind geoscientists that 1) tsunami hazard is everything but impossible and 2) tsunami come in all shapes and colours, and even a small event can result in serious damages and loss of lifes. In such a scenario, risk communication about Mediterranean Tsunami is a challenging enterprise. According to Astarte project, which investigated people’s knowledge, preparedness and attitudes to cope with Tsunami within six test sites across different nations, people have little knowledge about tsunamis, are likely to underestimate both probability and consequences of such events, and their understanding is significantly affected by media coverage (and social imagery) of big events such as the 2004 Sumatra Tsunami and the 2011 TohokuTsunami (Astarte, 2014). In such a scenario, where low probability and high uncertainty match with poor knowledge and familiarity with tsunami hazard, risk communicators should avoid undue assumptions about public’s supposed attitudes and preparedness, that may results in serious consequences for the exposed population, geoscientists, and civil protection officers. Hence, scientists must carefully shape their messages and rely on well-researched principled practices rather on good intuition (Bostrom, & Löfstedt, 2003). For these reasons, the Centro Allerta Tsunami of the Istituto Nazionale di Geofisica e Vulcanologia, to ground aneffective science communication strategy, promoted a survey to investigate tsunami’s risk perception in two pilot regions of southern Italy, as to represent about 3.2mln people living in 183 coastal municipalities.The research is based on a sample of > 1000 people, organized into six main sections: socio-demographic data and information on respondents’ territory; knowledge and sources of information on tsunami risk; contextualperception of risk posed by tsunamis; social representations of tsunami; role of cultural attitudes and worldviews;messages and channels to be used for tsunami early warning. Interviews will be administered within the end of February 2018, first data will be presented and discussed in this session.

Over the past few years, several attempts have been performed to find alternative “chemical proxies” in order to discriminate “tsunami backwash deposits” from “typical marine sediments”. A wide range of statistical tools has been selected in order to investigate the sediments and/or terrestrial soils transportation mechanism during the tsunami inundation period by using several types of chemical tracers. To relate the physical and chemical characteristics of Typical Marine Sediments (TMS),Tsunami Backwash Deposits (TBD), Onshore Tsunami Deposits (OTD) and Coastal Zone Soils (CZS) with their synchrotron radiation based micro-X-ray Fluorescence (μ-SXRF) spectra, the μ- SXRF spectra were built in the appropriate selected spectra range from 3,000 eV to 8,000 eV. Further challenges were considered by using the first-order derivative μ-SXRF spectra coupled with Probability Distribution Function (PDF), Hierarchical Cluster Analysis (HCA) and Principal Component Analysis (PCA) in order to investigate the elemental distribution characteristics in various types of terrestrial soils and marine sediments. Dendrographic classifications and multi-dimensional plots of principal components (i.e. bi-polar and three dimensional plots) could indicate the impacts of terrestrial soils and/or marine sediments transport on onshore and/or offshore during the tsunami inundation period. Obviously, these advanced statistical analyses are quite useful and provide valuable information and thus shed new light on the study of paleotsunami.

- by Waraporn Tanthanuch and +2
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- Sedimentology, Disaster Studies, Disaster risk management, Natural Hazards
- by Andrea Cerase
- •
- Sociology of Disaster, Geography, Geology, Disaster Studies

Il Bacino del Mediterraneo ha una ricca storia di terremoti ed eruzioni vulcaniche, che si può ritenere nota a tutti: non credo ci sia qualcuno in Italia, in Grecia o in Turchia che non sia consapevole della elevata sismicità della regione dove vive. Lo stesso discorso vale probabilmente per le eruzioni vulcaniche.Chi in Italia non ha sentito parlare dell’eruzione di Pompei del 79 d.C., o di quelle che avvengono frequentemente a Stromboli o all’Etna? Il discorso è ben diverso invece pergli tsunami (detti anche maremoti). Si può ipotizzare che la maggior parte degli italiani non conosca i precedenti storici in Italia e negli altri Paesi del Mediterraneo e per questo motivo non consideri il fenomeno come un rischio concreto. Probabilmente, ciò è dovuto soprattutto al fatto che gli tsunami si verificano meno frequentemente dei terremoti. In Italia l’ultimo grande maremoto, con danni considerevoli e molte vittime, risale a oltre un secolo fa, in seguito al terremoto di Messina e Reggio Calabria del 1908. Quando non c’è la memoria diretta, è molto difficile tramandare la consapevolezza di un rischio. In casi come quello del 1908, poi, l’evento terremoto tende per la sua tragicità a oscurare l’evento tsunami. Tuttavia, basta guardare una carta che riporta il catalogo dei maremoti del Mediterraneo per capire come la sensazione di basso rischio sia fallace. Si notano infatti decine di tsunami che sono avvenuti in molte zone delMare Nostrum, da Gibilterra al Medio Oriente(Fig. 1, Maramai et al., 2014). I terremoti costituiscono la principale causa di tsunami, sia a livello globale che nel Mediterraneo, con una percentuale intorno all’80% del totale dei maremoti. Meno frequenti quelli indotti da frane ed eruzioni vulcaniche, eccezionali quelli da impatto di meteoriti. In particolare, sono i grandi terremoti di subduzione quelli che hanno il maggiore potenziale tsunamigenico. Basti pensare ai due mega-terremoti dell’Indonesia del 2004 e del Giappone del 2011, entrambi di magnitudo pari o superiore a 9, che hanno generato degli tsunami di decine di metri di altezza devastando le coste prossime all’epicentro del terremoto e propagandosi anche attraverso l’oceano Indiano e il Pacifico. A parte questi casi eclatanti, in cui sono stati stimati degli spostamenti del fondale oceanico fino a decine di metri, più spesso avvengono degli tsunami meno devastanti ma comunque dannosi. Nel Mediterraneo, le zone di subduzione dell’arco ellenico, di Cipro e probabilmente anche quella dello Ionio sono tra le aree a maggiore potenziale tsunamigenico; esistono poi altre aree sismiche marine o costiere che sono state in passato sede di terremoti tsunamigenici, come le coste nordafricane, il già citato Stretto di Messina, il basso Adriatico, il Mar Ligure (Fig. 1). Se è vero che la frequenza di questi eventi è minore di quella dei terremoti, bisogna considerare che il loro impatto può essere devastante. importante mettere in atto tutte le possibili azioni per mitigare il rischio.

- by Andrea Cerase
- •
- Flood Risk Management, Seismic Hazard, Disaster risk management, Risk regulation

Historically, the Nicobarese of the Andaman and Nicobar Islands have lived in isolation with sporadic cross-cultural contact. Relying on the traditional knowledge and the resources provided by their ecosystem, the indigenes subsisted independently in their tribal reserve until the Indian Ocean tsunami inundated the Nicobar archipelago. Post-tsunami, the ANI administration undertook massive humanitarian interventions in the southern Nicobar Islands. This article analyses the post-tsunami sociocultural change among the Nicobarese against the backdrop of the humanitarian aid administration that began in December 2004. The article specifically inquires into the post-tsunami strategic-spatial interventions in the Nicobarese ecological niche and argues that the change after the tsunami has been tacitly engineered through humanitarian interventions.

- by Ajay Saini
- •
- Sociology, Cultural Studies, Social Change, Sociology of Disaster

The Indian Tsunami Early Warning Centre (ITEWC) in Hyderabad monitored the 11 April 2012
tsunami off the coast of Sumatra, which was generated by a shallow strike–slip earthquake and it
largest aftershock of magnitude Mw (mB) 8.5 and 8.2 respectively, that occurred inside the subducting
slab of the Indian plate. The earthquake generated a small ocean-wide tsunami that has been
recorded by various tide gauges and tsunami buoys located in the Indian Ocean region. ITEWC
detected the earthquake within 3 min 52 s and issued six advisories (bulletins) according to its
Standard Operating Procedure. The ITEWC performed well during the event, and avoided false
alarms and unnecessary public evacuations, especially in the mainland part of India region.

- by Uma Devi E
- •
- Tsunami Research

The repetitive narrative that, "Tsunami waves and receded coastal water initiated by an earthquake are closely related," is analyzed through the sequential events that followed the earthquake; a mechanism based on the interaction of receded water with magma is suggested to explain the amplification of Tsunami wave deep beneath the ocean floor (Fig.1), where earthquake occurred under the seabed's or in coastline; the mechanism explained how the water is amplified into steam in the magma chamber, as its volume increased 1,700 times, the transformed water encompass the tremendous force that uplifted the ocean water endowed it with such destructive force; the mechanism explained characteristics related to Tsunami wave, including relation with earthquake and volcano, receding costal water, the foams, inundation, runup, the nature of the great force of Tsunami, ideas to calculate the magnitude of Tsunami force and energy, volume of receded water, volume of tsunami wave, the repetition of its wave; these and related issues are stated; the idea is derived based on the continual flow of lava from earth's interior and the existence of magma reservoir bellow earth's surface in places like Yellowstone in USA and hotspot beneath Hawaii, such magma chamber when existed under seabed, if opened by crack during earthquake, can easily lead to an interaction between receded water and the magma, resulted in the suggested mechanism, all is based on logical analyses and deep thinking to attained the Tsunami Mechanism in response to 2004 and 2011 human tragedies; thus understanding this mechanism will help laying measures to counter the phenomenon, which will reflect positively in saving lives and mitigate its destructive force and reduce consequences of its impact on local societies and above all to understand its true mechanism.

- by Mahmoud E . Yousif
- •
- Tsunamigenic Earthquakes, Tsunami Research, Tsunami Modeling

During the Holocene, numerous great earthquakes have occurred along the west coast of North America. Enormous seismic waves, triggered by these colossal forces of nature, have episodically inundated vulnerable regions of the Cascadia coastal lands to elevations of up to 20 m above mean sea level. The destructive paths of tsunamis leave behind important geological evidence like anomalous sheets of gravel and sand containing marine fossils and terrestrial detritus marking a distinct disturbance in the depositional environment. Such tsunamigenic deposits can be found in low-elevation lakes; depositional environments which allow one to determine the distribution and inland range of the tsunami wave run-up but also ideal environments because they tend to preserve a longer and older sedimentological record. Multiple inferred tsunami deposits were recorded in Kakawis Lake, on the west central coast of Vancouver Island, and have provided a 14,000-year-old record of information. The tsunamig...

- by Gloria I. López
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- Coastal Processes, Tsunami, Tsunami Research, Tsunamis in Coastal Lakes

The 26 th December 2004 Indian Ocean Tsunami (IOT) emanated from an Mw 9.2 earthquake that generated a 1600 km-long rupture along the Sumatran Megathrust and generated tsunami waves up to 30 m high. The IOT directly impacted the Bay of Bengal and east Africa, with over 283,000 people perishing. At the time, this catastrophic event was considered unprecedented and sparked intense investigations to test this claim. It is now believed that four pre-2004 IOT events have occurred in the last 2500 years, recurring every 550 to 700 years. Much of this information comes from Phra Thong Island, Thailand, where a sequence of four stacked sandsheets separated by organic units has been recognised and compared to the 2004 IOT event. Recently, ground-penetrating radar on Phra Thong Island identified a region that could not be explained by the known stratigraphy. The stratigraphy of the area was investigated from auger cores and pits, and several previously-unrecognised sandsheets were identified ...

- by Kruawun Jankaew
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- Tsunami, Tropical cyclones, Tsunami Hazard, Tsunami Research

In the wake of the devastating 2011 Tōhoku earthquake and tsunami, the Central Disaster Management Council of the Japanese Cabinet Office issued new guidance for assessing seismic hazards in Japan. Before 2011, seismic hazard assessment relied on source models developed from knowledge of a small number of well-documented historical earthquakes. Less well-known historical earthquakes, including the AD 869 Jōgan Sanriku earthquake, were largely disregarded as their seismic intensities or tsunami heights could not be reconciled with the chosen seismic sources. Following the unexpectedly large size of the Tōhoku earthquake, the Cabinet Office advocated renewed investigation of earthquake and tsunami occurrence over historical and longer timescales, with a particular focus on defining the largest possible magnitudes. The new guidelines pay close attention to the Nankai Trough, the subduction zone where the Philippine Sea Plate dives beneath the Eurasian Plate. The Nankai Trough faces the densely populated and highly industrialised coastline of south central Japan and harbours a widely-known seismic gap along its eastern Tōkai segment. A full-length rupture of the Nankai Trough, including the Tōkai segment, could produce an earthquake with a magnitude approaching that of the 2011 event, with tsunami travel times to the closest shorelines of less than 30 minutes. Here, we review geological evidence for past earthquakes and tsunamis along the Nankai Trough. This evidence comes from a wide variety of sources, including uplifted marine terraces, turbidites, liquefaction features, subsided marshes and tsunami deposits in coastal lakes and lowlands. Examining papers published before and after 2011, we investigate the impact of the new Cabinet Office guidelines on attempts to understand the magnitude and recurrence of these events. We summarise current knowledge of the largest paleoearthquakes and paleotsunamis and make recommendations for further investigations of this highly critical subduction zone.

- by Purna S. Putra
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- Geoarchaeology, Tsunami, Tsunamigenic deposit, Tsunami Research

Se identifico y evaluo la vulnerabilidad de un total de 227 edificaciones asociadas al turismo en la ciudad puerto de Valparaiso, que se encuentran en el area de inundacion definida para el peor escenario conocido para la zona. Se utilizo el Modelo de Evaluacion de la Vulnerabilidad por Tsunami de Papathoma (PTVA-3). Los resultados muestran que las edificaciones asociadas al alojamiento, como hoteles, presentan bajos indices de vulnerabilidad, por lo que se recomienda considerar la evacuacion vertical en estos casos. Las otras tipologias –alimentacion, atractivos y servicios– tambien presentan en general bajos indices de vulnerabilidad, pero con mayor dispersion. El puerto y la linea ferroviaria se han transformado en una barrera de proteccion y exclusion de emplazamientos de edificaciones en las zonas mas expuestas. En los sectores emplazados entre la linea ferrea y la linea costera, tales como Caleta Portales y Muelle Baron, se concentran las edificaciones con mayor indice de vuln...

Wilayah Maluku merupakan salah satu daerah di timur Indonesia yang memiliki potensi tsunami yang cukup tinggi, ini dibuktikan dengan lebih dari 25 kejadian tsunami yang terekam di daerah Maluku dari tahun 1629 – 2006 (katalog database tsunami online Gusiakov (2005), Puspito (2007) dan Katalog Gempa Merusak dan Tsunami BMKG), tsunami yang terbesar terjadi pada tanggal 17 Februari 1674 yang menewaskan lebih dari 2900 orang dengan run-up hingga mencapai 80 meter menghancurkan kota Ambon dan juga pada tanggal 12 Oktober 1899 yang menenggelamkan kota Amahai di Pulau Seram dengan korban tewas mencapai 4000 orang. Oleh karena itu perlu dilakukan pembuatan skenario tsunami untuk mendapatkan kemungkinan tinggi run-up yang bersumber di daerah perairan Maluku dengan menggunakan software Tsunami L-2008. Berdasarkan Katalog Gempabumi Signifikan dan Merusak 1821 – 2009 yang dikeluarkan BMKG, bahwa pada tanggal 28 Januari 2004 telah terjadi gempabumi di Maluku mengakibatkan tsunami yang terobserva...

- by Robby Wallansha
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- Tsunami, Tsunamis, Tsunamigenic Earthquakes, Tsunami Research

On June 22, 1932, a 10- to 12-m-high tsunami wave
struck *60 km off the Mexican Pacific coast. The associated
earthquake that apparently produced this tsunami is questionable
because of its relatively small magnitude (Ms = 6.9) to produce
such tsunami heights. Historical documents, survivor testimony,
tsunami catalogs, a post-tsunami survey report, together with
geomorphological interpretation of the continental shelf and slope,
and numerical modeling were combined to characterize the tsunami
parameters. Our results suggest that recorded maximum tsunami
wave height, horizontal inundation, arrival time, directivity, effects,
and damage are compatible with those characteristics related to an
underwater landslide tsunami. The associated landslide (slump) is
4.2 km long, 3.9 km wide, 0.448 km thick, and is located in the
upper continental shelf of the Armerı´a Canyon. Elucidating the
cause and mechanisms of the near-field 1932 tsunami would aid in
considering a wider spectrum of tsunami sources in hazard mitigation
programs of the Mexican Pacific coast.

- by Nestor Corona
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- Tsunami impact, Tsunami Research, Tsunami Modeling

Meuraxa region severe destruction after the tsunami last December 26, caused by aspects of the arrangement of the region that are not mitigated. That many buildings was built in the area of open space mitigation functions such as coastal border areas, coastal forests, buffer zones, and other open spaces. Meuraxa is a buffer area between the direction of the tsunami came and the center of Banda Aceh city. Some experts assess the Masterplan that was prepared by BAPPENAS still let buildings are rebuilt in the same site. By seeing the opportunity that there are still some undeveloped land, the existence of some unavailable open sites, the lack of studies in urban design aspects of tsunami mitigation based open space, underlies the need for a conceptual review of mitigated open spaces arrangement for this region. Began with the identification of conditions based on the magnitude of the tsunami threat structuring. Review of aspects that affect the mitigated function of protection or rescue with the technical provisions from the theoretical study. Proceed with the concept making with triangulation method that based by theory, regulation and expert opinion. And finally produce the concept of "utilization and optimization of natural elements for the protection, using structural protection as a supporter" for open space protection functions, and the concept of "ecological rescue space with escape hills, in order to support the basic concepts and the characteristics of the Meuraxa".

- by Donny Sumarto
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- Architecture, Urban Design, Tsunami Research
- by Shailesh Nayak
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- Multidisciplinary, Current Science, Tsunami Research

- by Klaus Schwarzer
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- Sedimentology, Disaster Studies, Disaster risk management, Natural Hazards

During the Holocene, numerous great earthquakes have occurred long the west coast of North America. Enormous seismic waves, triggered by these colossal forces of nature, have episodically inundated vulnerable regions of the Cascadia coastal lands to elevations of up to 20m above mean sea level. The destruction paths of tsunamis leave behind important geological evidence like anomalous sheets of gravel and sand containing marine fossils and terrestrial detritus marking a distinct disturbance in the depositional environment. Such tsunamigenic deposits can be found in low-elevation lakes; depositional environments which allow to determine the distribution and inland range of the tsunami wave run-up but also ideal environments because they tend to preserve a longer and older sedimentological record. Multiple inferred tsunami deposits were recorded at Kakawis Lake, on the west central coast of Vancouver Island, and have provided a 14,000-year-old record of information. The tsunamigenic sediments pre-date AD1700 and are similar to those found in other lakes on the Island. As for a regional correlation, these tsunami deposits are likely related to at least two and possibly three of the events reported in the Atwater - Hemphill-Haley chronology, with recurrence intervals of about 400 years.

- by Gloria I. López
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- Coastal Processes, Tsunami, Tsunami Research, Tsunamis in Coastal Lakes
- by Alessandro Amato
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- Sociology of Disaster, Geography, Geology, Disaster Studies

- by Charlie Bristow
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- Geology, Medicine, Tsunami, Tropical cyclones
- by M. Crescimbene
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- Sociology of Disaster, Geography, Geology, Disaster Studies
- by Maria-Teresa Ramirez-Herrera
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- Geophysics, Tsunami impact, Tsunami Research, Tsunami Modeling
- by Maria-Teresa Ramirez-Herrera
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- Geology, Tsunami Research

The occurrence of tsunami waves on the eastern Caribbean Venezuelan coasts during 5 Venezuelan (local) earthquakes (01-IX-1530, 15-VII-1853, 29-X-1900, 17-I-1929 and 9-VII-1997), have been confirmed through the search and evaluation of written accounts by primary sources (eye witnesses) of tsunami inundation during these events. Among the outcomes of this new assessment are: 1) the run-up heights of several of those tsunamis have been substantially reduced. In fact, maximum run-up heights for the 5 tsunamis are: 5-7 m at Cumaná for the 1530 event, 5 m at Barlovento and 3 m at the Neverí mouth for the 1900 tsunami, 3 m at western Cumaná for the 1853 and 1929 events and about 1 m for the 1997 earthquake. 2) These new estimates on wave heights for local earthquakes restrict the search for tsunamites by trenching and coring to mainly the first 500-m-wide strip from the coastline in low-lying flatlands. The source of these tsunami waves may be complex. Some are the result of coastal-submarine sliding (1929 AD, 1997 AD), tectonic slip on active strike-slip (or normal oblique slip) faults (1530 AD, 1900 AD) or combination of tectonic slip and sliding (1853 AD). Appropriate numerical modeling of tsunami wave generation , migration and inundation are urgently in need to understand these tsunami mechanics.

- by Franck Audemard
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- Tsunamigenic Earthquakes, Tsunami impact, Tsunami Hazard, Tsunami Research
- by Yuichi Nishimura
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- Geology, Geoarchaeology, Tsunami, Tsunamigenic deposit