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1.

Given the recent historical disastrous tsunamis and the knowledge that the Arabian Gulf (AG) is tectonically active, this study aimed to evaluate tsunami hazards in Kuwait from both submarine earthquakes and subaerial landslides. Despite the low or unknown tsunami risks that impose potential threats to the coastal area’s infrastructures and population of Kuwait, such an investigation is important to sustain the economy and safety of life. This study focused on tsunamis generated by submarine earthquakes with earthquake magnitudes (M w ) of 8.3–9.0 along the Makran Subduction Zone (MSZ) and subaerial landslides with volumes of 0.75–2.0 km3 from six sources along the Iranian coast inside the AG and one source at the Gulf entrance in Oman. The level of tsunami hazards associated with these tsunamigenic sources was evaluated using numerical modeling. Tsunami model was applied to conduct a numerical tsunami simulation and predict tsunami propagation. For landslide sources, a two-layer model was proposed to solve nonlinear longwave equations within two interfacing layers with appropriate kinematic and dynamic boundary conditions. Threat level maps along the coasts of the AG and Kuwait were developed to illustrate the impacts of potential tsunamis triggered by submarine earthquakes of different scales and subaerial landslides at different sources. GEBCO 30 arc-second grid data and others were used as bathymetry and topography data for numerical modeling. Earthquakes of M w 8.3 and M w 8.6 along the MSZ had low and considerable impacts, respectively, at the Gulf entrance, but negligible impacts on Kuwait. An earthquake of M w 9.0 had a remarkable impact for the entire Gulf region and generated a maximum tsunami amplitude of up to 0.5 m along the Kuwaiti coastline 12 h after the earthquake. In the case of landslides inside the AG, the majority impact occurred locally near the sources. The landslide source opposite to Kuwait Bay generated the maximum tsunami amplitudes reaching 0.3 m inside Kuwait Bay and 1.8 m along the southern coasts of Kuwait.

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2.
The 1945 Tsunami generated due to Makran Earthquake in the Arabian Sea was the most devastating tsunami in the history of the Arabian Sea and caused severe damage to property and loss of life. It occurred on 28th November 1945, 21:56 UTC (03:26 IST) with a magnitude of 8.0 (M w), originating off the Makran Coast of Pakistan in the Arabian Sea. It has impacted as far as Mumbai in India and was noticed up to Karvar Coast, Karnataka. More than 4,000 people were killed as a result of the earthquake and the tsunami. In this paper an attempt is made for a numerical simulation of the tsunami generation from the source, its propagation into the Arabian Sea and its effect on the western coast of India through the use of a numerical model, referred to as Tunami-N2. The present simulation is carried out for a duration of 300 min. It is observed from the results that the simulated arrival time of tsunami waves at the western coast of India is in good agreement with the available data sources. The paper also presents run-up elevation maps prepared using Shuttle Radar Topographic Mission (SRTM) data, showing the possible area of inundation due to various wave heights along different parts of the Gujarat Coast. Thus, these results will be useful in planning the protection measures against inundation due to tsunami and in the implementation of a warning system.  相似文献   

3.
Turkey was struck by two major events on 17 August and 12 November 1999, named Izmit (M w = 7.4) and Düzce (M w = 7.2) earthquakes, respectively. Rubble mound breakwaters in Izmit Bay experienced little damage, as forecasted by the new risk assessment model in which tsunami occurrence risk was included in the damage estimations. In order to determine the occurrence probability of structural damage under design conditions, including the environmental loading parameters of tsunami and storm waves, tidal range and storm surge, the Conditional Expections Monte Carlo simulation was applied in the risk assessment model developed in this study for the Esenköy Fishery Harbour, Turkey. A tsunami was not the key design parameter when compared to storm waves for the main breakwater of the harbour, however, in places with great seismic activity, the tsunami risk should be important depending on the occurrence probability and magnitude of the tsunami.  相似文献   

4.
Tokutaro Hatori 《GeoJournal》1996,38(3):313-319
The regional characteristics of tsunami magnitudes in the SE Asia region are discussed in relation to earthquake magnitudes during the period from 1960 to 1994. Tsunami magnitudes on the Imamura-Iida scale are investigated by the author's method (Hatori 1979, 1986) using the data of inundation heights near the source area and tide-gauge records observed in Japan. The magnitude values of the Taiwan tsunamis showed relatively to be small. On the contrary, the magnitudes of tsunamis in the vicinities of the Philippines and Indonesia exceed more than 1–2 grade (tsunami heights: 2–5 times) compared to earthquakes with similar size on the circum-Pacific zone. The relation between tsunami magnitude, m, and earthquake magnitude, M s, is expressed as m = 2.66 M s– 17.5 for these regions. For example, the magnitudes for the 1976 Mindanao tsunami (M s= 7.8, 3702 deaths) and the 1992 Flores tsunami (M s= 7.5, 1713 deaths) were determined to be m = 3 and m = 2.5, respectively. The focal depth of tsunamigenic earthquakes is shallower thand< 36 km, and the detectively of tsunamis is small for deep earthquakes being d > 40 km. For future tsunamis, it is indispensable to take precautions against shallow earthquakes having the magnitudes M s> 6.5.  相似文献   

5.
Coastal vegetation is widely recognized to reduce tsunami damage to people and buildings, and it has been studied recently because it requires relatively little capital investment compared with artificial measures, provides human-friendly beach fronts, and enhances inter-relationships with other ecological systems. However, the tsunami caused by the Great East Japan Earthquake at 14:46 JST on March 11, 2011, with a magnitude of 9.0 and epicenter 129?km east of Sendai, broke most of the sea wall (tsunami gates, large embankments) and caused catastrophic damage to coastal forests in the Tohoku and Kanto districts of Japan. A field survey was conducted to elucidate the critical breaking condition of Japanese coastal pine trees. Tree-trunk breakage was observed when the sea embankment was washed out or when there was no sea embankment and the tree was under strong inertia force or impact force by debris. Even though the trunk bending and breaking phenomena are different, statistical analysis showed that the critical diameters for trunk bending and trunk breaking were not very different. The overturning phenomenon is a little more complex than trunk breaking because the resistive force is a function of the substrate and root anchorage. An equation to determine the critical diameters for trunk bending, trunk breaking, and overturning was derived as a function of tsunami water depth, soil-root strength, and the hydrodynamic parameter (H D ) formulated by Froude number, drag coefficient, and the ratio of impact force to drag force considering the physical mechanisms to resist the tsunami. Trunk bending and breaking were closely related to tsunami water depth and the hydrodynamic parameter (H D ), but tree overturning was found to be more site specific, and the root-soil strength greatly affected the critical value. The proposed critical diameter equation and its coefficient are useful for the design of an inland forest of pine trees that can trap large trees, cars, debris, etc., to its breaking limit. The trapping function should be utilized more in the future designs of inland forests, if possible, on embankments.  相似文献   

6.
We present the seismic energy, strain energy, frequency–magnitude relation (b-value) and decay rate of aftershocks (p-value) for the aftershock sequences of the Andaman–Sumatra earthquakes of December 26, 2004 (M w 9.3) and March 28, 2005 (M w 8.7). The energy released in aftershocks of 2004 and 2005 earthquake was 0.135 and 0.365% of the energy of the respective mainshocks, while the strain release in aftershocks was 39 and 71% for the two earthquakes, respectively. The b-value and p-value indicate normal value of about 1. All these parameters are in normal range and indicate normal stress patterns and mechanical properties of the medium. Only the strain release in aftershocks was considerable. The fourth largest earthquake in this region since 2004 occurred in September 2007 off the southern coast of Island of Sumatra, generating a relatively minor tsunami as indicated by sea level gauges. The maximum wave amplitude as registered by the Padang, tide gauge, north of the earthquake epicenter was about 60 cm. TUNAMI-N2 model was used to investigate ability of the model to capture the minor tsunami and its effect on the eastern Indian Coast. A close comparison of the observed and simulated tsunami generation, propagation and wave height at tide gauge locations showed that the model was able to capture the minor tsunami phases. The directivity map shows that the maximum tsunami energy was in the southwest direction from the strike of the fault. Since the path of the tsunami for Indian coastlines is oblique, there were no impacts along the Indian coastlines except near the coast of epicentral region.  相似文献   

7.
Xu  Zhiguo  Sun  Lining  Rahman  Mohd Nashriq Abd  Liang  Shanshan  Shi  Jianyu  Li  Hongwei 《Natural Hazards》2022,111(3):2703-2719

A major left-lateral strike-slip Mw7.7 earthquake occurred in the vicinity of the Caribbean Sea on January 28, 2020. As a result, a small-scale tsunami was generated. The properties of the seismogenic source were described using observational data gathered for the earthquake and tsunami, as well as information on the regional tectonic setting. The tsunami was simulated with the COMCOT model and Okada’s dislocation model from finite fault solutions for MW7.7 Caribbean Sea earthquakes published by the United States Geological Survey. The simulation results were compared to tide gauge records to validate whether the seafloor’s vertical displacement generated by the strike-slip fault caused a small-scale tsunami. We conducted a spectral analysis of the tsunami to better understand the characteristics of tsunami records. The tsunami simulation results showed that the co-seismic vertical displacement caused by a strike-slip MW7.7 earthquake could have contributed to the small-scale tsunami, but the anomalously large high-frequency tsunami waves recorded by the George Town tide gauge 11 min after the earthquake were unrelated to the earthquake-generated tsunami. According to the spectrum analysis, the predominant period of noticeable high-frequency tsunami waves recorded by the George Town tide gauge occurred only two minutes after the earthquake. This indicates that the source of the small-scale tsunami was close to the George Town station and the possible tsunami source was 150 km away from George Town station. These facts suggest that a submarine landslide was caused by the strike-slip earthquake. The comprehensive analysis showed that the small-scale tsunami was not caused solely by co-seismic seafloor deformation from the strike-slip event but that an earthquake-triggered submarine landslide was the primary cause. Therefore, the combined impact of two sources led to the small-scale tsunami.

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8.
Both seismic and tsunami hazards design criteria are essential input to the rehabilitation and long-term development of city of Banda Aceh Post Sumatra 2004 (M w=9.3) disaster. A case study to develop design criteria for future disaster mitigation of the area is presented. The pilot study consists of probabilistic seismic and tsunami hazard analysis. Results of the probabilistic seismic hazard analysis indicates that peak ground acceleration at baserock for 10 and 2% probability of exceedance in 50 years is 0.3 and 0.55 g, respectively. The analysis also provides spectral values at short (T=0.2 s) and long period (T=1.0 s) motions. Some non-linear time-domain earthquake response analyses for soft, medium, and hard site-class were conducted to recommend design response spectra for each site-class. In addition, tsunami inundation maps generated from probabilistic tsunami hazard analysis were developed through tsunami wave propagation analysis and run-up numerical modeling associated with its probability of tsunamigenic earthquake source potential. Both the seismic and tsunami hazard curve and design criteria are recommended as contribution of this study for design criteria, as part of the disaster mitigation effort in the development process of the city. The methodology developed herein could be applied to other seismic and tsunami disaster potential areas.  相似文献   

9.
Since 1964, the Geophysical Laboratory in Tahiti has been charged with the responsibility of issuing tsunami warnings. But this research laboratory is also designed to conduct other missions. One of them is to study an oversee seismicity and volcanism in the South Central Pacific. For this activity the Geophysical Laboratory, which is also the French Polynesia Tsunami Warning Center (Centre Polynésien de Prévention des Tsunamis — CPPT), processes the data recorded by the Polynesian Seismic Network which includes 21 short-period stations, 4 broad-band three-component long period stations, and 2 tide gauge stations. These stations are, for the most, telemetered to CPPT in Tahiti which is equipped wilh data processing capabilities.At CPPT, Tsunami Warning is based on the measurement of the Seismic Moment through the mantle magnitudeM m and the proportionality of observed tsunami height to this seismic moment.The new mantle magnitude scale,M m, uses the measurement of the mantle of Rayleigh and Love wave energy in the 50–300 s period range and is directly related to the seismic moment throughM m = logM o – 20. Knowledge of the seismic moment allows an estimation of a range of high seas amplitudes for the expectable tsunami.The relation that estimates the tsunami height according to the seismic moment is based on the normal mode tsunami theory but also fits a dataset of 17 tsunamis recorded at Papeete (PPT) since 1958. This procedure is fully automatic: a computer detects, locates and estimates the seismic moment through theM m magnitude and, in terms of moment, gives an amplitude window for the expected tsunami. These-several operations are executed in real time. In addition, the operator can use historical references and, if necessary, acoustic T waves.This automatic procedure, which has been operating at the CPPT since 1986, is certainly transposable and applicable to other tsunami warning centers that issue warnings for earthquakes detected more than 1000 km away, and has significant potential in the regional field.  相似文献   

10.
Asteroid impact spherule layers and tsunami deposits underlying banded iron-formations in the Fortescue and Hamersley Groups have been further investigated to test their potential stratigraphic relationships. This work has included new observations related to the ca 2.63 Ga Jeerinah Impact Layer (JIL) and impact spherules associated with the 4th Shale-Macroband of the Dales Gorge Iron Member (DGS4) of the Brockman Iron Formation. A unit of impact spherules (microkrystite) correlated with the ca 2.63 Ga JIL is observed within a >100 m-thick fragmental-intraclast breccia pile in drill cores near Roy Hill. The sequence represents significant thickening of the impact/tsunami unit relative to the JIL type section at Hesta, as well as relative to the 20–30 m-thick ca 2.63 Ga Carawine Dolomite spherule-bearing mega-breccia. The ca 2.48 Ga-old Dales Gorge Member of the Brockman Iron Formation is underlain by an ?0.5 m-thick rip-up clast breccia located at the top of the ca 2.50 Ga Mt McRae Shale, and is interpreted as a tsunami deposit. We suggest that the presence of impact ejecta and tsunami units stratigraphically beneath a number of banded iron-formations, and units of ferruginous shale in the Pilbara and South Africa may result from a genetic relationship. For example, it could be that under Archean atmospheric conditions, mafic volcanism triggered by large asteroid impacts enriched the oceans in soluble FeO. If so, seasonal microbial and/or photolytic oxidation to ferric oxide could have caused precipitation of Fe2O3 and silica. In view of the possible occurrence of depositional gaps and paraconformities between impact ejecta units and overlying ferruginous sediments, these relationships require further testing by isotopic age studies.  相似文献   

11.
To explore the local tsunami hazard from the Cascadia subduction zone we (1) evaluate geologically reasonable variability of the earthquake rupture process, (2) specify 25 deterministic earthquake sources, and (3) use resulting vertical coseismic deformations for simulation of tsunami inundation at Cannon Beach, Oregon. Maximum runup was 9–30 m (NAVD88) from earthquakes with slip of ~8–38 m and M w ~8.3–9.4. Minimum subduction zone slip consistent with three tsunami deposits was 14–15 m. By assigning variable weights to the source scenarios using a logic tree, we derived percentile inundation lines that express the confidence level (percentage) that a Cascadia tsunami will not exceed the line. Ninety-nine percent of Cascadia tsunami variation is covered by runup ≤30 m and 90% ≤16 m with a “preferred” (highest weight) value of ~10 m. A hypothetical maximum-considered distant tsunami had runup of ~11 m, while the historical maximum was ~6.5 m.  相似文献   

12.
《International Geology Review》2012,54(12):1462-1470
The Pacific coast of Mexico has repeatedly been exposed to destructive tsunamis. Recent studies have shown that rock magnetic methods can be a promising approach for identification of tsunami- or storm-induced deposits. We present new rock magnetic and anisotropy of magnetic susceptibility (AMS) results in order to distinguish tsunami deposits in the Ixtapa–Zihuatanejo area. The sampled, 80 cm-deep sequence is characterized by the presence of two anomalous sand beds within fine-grained coastal deposits. The lower bed is probably associated with the 14 March 1979 Petatlán earthquake (M W = 7.6), whereas the second one formed during the 21 September 1985 Mexico earthquake (M W = 8.1). Rock magnetic experiments discovered significant variations within the analysed sequence. Thermomagnetic curves reveal two types of behaviour: one in the upper part of the sequence, after the occurrence of the first tsunami, and the other in the lower part of the sequence, during that event and below. Analysis of hysteresis parameter ratios in a Day plot also allows us to distinguish two kinds of behaviour. The samples associated with the second tsunami plot in the pseudo-single-domain area. In contrast, specimens associated with the first tsunami and the time between both tsunamis display a very different trend, which can be ascribed to the production of a considerable amount of superparamagnetic grains, which might be due to pedogenic processes after the first tsunami. The studied profile is characterized by a sedimentary fabric with almost vertical minimum principal susceptibilities. The maximum susceptibility axis shows a declination angle D = 27°, suggesting a NNE flow direction which is the same for both tsunamis and normal currents. Standard AMS parameters display a significant enhancement within the transitional zone between both tsunamis. The study of rock magnetic parameters may represent a useful tool for the identification and understanding of tsunami deposits.  相似文献   

13.
We present a preliminary estimation of tsunami hazard associated with the Makran subduction zone (MSZ) at the northwestern Indian Ocean. Makran is one of the two main tsunamigenic zones in the Indian Ocean, which has produced some tsunamis in the past. Northwestern Indian Ocean remains one of the least studied regions in the world in terms of tsunami hazard assessment. Hence, a scenario-based method is employed to provide an estimation of tsunami hazard in this region for the first time. The numerical modeling of tsunami is verified using historical observations of the 1945 Makran tsunami. Then, a number of tsunamis each resulting from a 1945-type earthquake (M w 8.1) and spaced evenly along the MSZ are simulated. The results indicate that by moving a 1945-type earthquake along the MSZ, the southern coasts of Iran and Pakistan will experience the largest waves with heights of between 5 and 7 m, depending on the location of the source. The tsunami will reach a height of about 5 m and 2 m in northern coast of Oman and eastern coast of the United Arab Emirates, respectively.  相似文献   

14.
Community-scale estimates of building damage and economic loss are modeled for Seaside, Oregon, for Cascadia subduction zone events ranging from 8.7 to 9.3 MW with corresponding slip distances of 3–25 m considering only the effects of the tsunami. Numerical simulations are obtained from the National Oceanic and Atmospheric Administration’s method of splitting tsunami model which includes a source model, subsidence, and calculations of the propagation and inundation flow characteristics. The damage estimates are based on fragility curves from the literature which relate flow depth with probability of damage for two different structural materials of buildings. Calculations are performed at the parcel level for the inundation hazard without including damage caused by the earthquake itself. Calculations show that the severity of building damage in Seaside is sensitive to the magnitude of the event or degree of slip because the majority of the city is located on low-lying coastal land within the estimated inundation zone. For the events modeled, the percentage of building within the inundation zone ranges from 9 to 88 %, with average direct economic losses ranging from $2 million to $1.2 billion.  相似文献   

15.
The “PTVAM” tsunami vulnerability assessment model [Papathoma and Dominey-Howes: 2003, Nat. Hazards Earth Syst. Sci. 3, 733–744; Papathoma et al.: 2003, Nat. Hazards Earth Syst. Sci. 3, 377–389], like all models, requires validation. We use the results from post-tsunami surveys in the Maldives following the December 26, 2004 Indian Ocean tsunami to ‘evaluate’ the appropriateness of the PTVAM attributes to understanding spatial and temporal vulnerability to tsunami damage and loss. We find that some of the PTVAM attributes are significantly important and others moderately important to understanding and assessing vulnerability. Some attributes require further investigation. Based upon the ground-truth data, we make several modifications to the model framework and propose a revised version of the PTVAM (PTVAM 2).  相似文献   

16.
The December 2004 Indian Ocean Tsunami (IOT) had a major impact on the geomorphology and sedimentology of the east coast of India. Estimation of the magnitude of the tsunami from its deposits is a challenging topic to be developed in studies on tsunami hazard assessment. Two core sediments (C1 and C2) from Nagapattinam, southeast coast of India were subjected to textural, mineral, geochemical and rock-magnetic measurements. In both cores, three zones (zone I, II and III) have been distinguished based on mineralogical, geochemical and magnetic data. Zone II is featured by peculiar rock-magnetic, textural, mineralogical and geochemical signatures in both sediment cores that we interpret to correspond to the 2004 IOT deposit. Textural, mineralogical, geochemical and rock-magnetic investigations showed that the tsunami deposit is featured by relative enrichment in sand, quartz, feldspar, carbonate, SiO 2, TiO 2, K 2O and CaO and by a depletion in clay and iron oxides. These results point to a dilution of reworked ferromagnetic particles into a huge volume of paramagnetic materials, similar to what has been described in other nearshore tsunami deposits (Font et al. 2010). Correlation analysis elucidated the relationships among the textural, mineral, geochemical and magnetic parameters, and suggests that most of the quartz-rich coarse sediments have been transported offshore by the tsunami wave. These results agreed well with the previously published numerical model of tsunami induced sediment transport off southeast coast of India and can be used for future comparative studies on tsunami deposits.  相似文献   

17.
Jain  Nikita  Virmani  Deepali  Abraham  Ajith 《Natural Hazards》2021,106(1):139-172

In the last fifteen years, tsunami science has progressed at a rapid pace. Three major tsunamis: The Indian Ocean in 2004, the 2011 Tohoku tsunami, and the 2018 Palu tsunami were significant landmarks in the history of tsunami science. All the three tsunamis, as mentioned, suffered from either no warning or poor reception of the alerts issued. Various lessons learned, consequent numerical models proposed, post-2004 tsunami damage findings manifested into solutions. However, the misperceived solutions led to a disastrous impact of the 2011 Tohoku event. In the following years, numerous improvements in warning systems and community preparedness frameworks were proposed and implemented. The contributions and new findings have added multi-fold advancements to tsunami science progress. Later, the 2018 Palu tsunami happened and again led to a massive loss of life and property. The warning systems and community seemed un-prepared for this non-seismic tsunami. A significant change is to take place in tsunami science practices and solutions. The 2018 tsunami is one of the most discussed and researched events concerning the palaeotsunami records, damage assessment, and source findings. In the new era, using machine learning and deep learning prevails in all the fields related to tsunami science. This article presents a complete 15-year bibliometric analysis of tsunami research from Scopus and Web of Science (WoS). The review of majorly cited documents in the form of a progressing storyline has highlighted the need for multidisciplinary research to design and propose practical solutions.

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18.
We assess tsunami hazards in San Diego Bay, California, using newly identified offshore tsunami sources and recently available high resolution bathymetric/topographic data. Using MOST (Titov and Synolakis, J Waterways Port Coastal Ocean Eng ASCE 124(4):57–171, 1998), we simulate locally, regionally and distant-generated tsunamis. Local tsunami source models use more realistic fault and landslide data than previous efforts. With the exception of the Alaska-Aleutian Trench, modeling results suggest that local sources are responsible for the largest waves within the San Diego Bay and Mission Bay. Because San Diego Bay is relatively well protected by North Island and the Silver Strand, the wave heights predicted are consistently smaller inside the harbor than outside. However, historical accounts, recent tsunamis and our predictions show that San Diego Bay is vulnerable to strong tsunami induced currents. More specifically, large currents are expected inside the harbor for various distant and local tsunami sources with estimated flow velocities exceeding 100 cm/s. Such currents have been damaging to harbor facilities, such as wharves and piers, and may cause boats to break from moorings and ram into adjacent harbor structures, as observed in recent historic tsunamis. More recently, following the M w 8.8 February 27, 2010 Chile earthquake, tsunami-currents damaged docks/piers in Shelter Island confirming our findings. We note that the first generation of inundation maps in use in San Diego County by emergency management was based on much larger “worst case but realistic scenarios” (Synolakis et al. 2002a), which reflected the understanding of offshore hazards pervasive ten years ago. Large inundation and overland flow depths were observed primarily in local tsunami source simulations. In particular, locally induced tsunamis appear capable to overtop the Silver Strand. The results suggest that further work needs to be carried out with respect to local tsunami sources as they seem to have worse impact in the San Diego region than previously thought but probably low probability of occurrence. We also predict that a coastal community can be devastated simultaneously by large waves inundating shores and large currents in locations with small flow depths.  相似文献   

19.
Vulnerability of buildings to debris flow impact   总被引：5，自引：1，他引：4  
Quantitative risk assessments (QRAs) for landslide hazards are increasingly being executed to determine an unmitigated level of risk and compare it with risk tolerance criteria set by the local or federal jurisdiction. This approach allows urban planning with a scientific underpinning and provides the tools for emergency preparedness. Debris-flow QRAs require estimates of the hazard probability, spatial and temporal probability of impact (hazard assessment) and vulnerability of the elements at risk. The vulnerability term is perhaps the most difficult to estimate confidently because (a) human death in debris flows is most commonly associated with building damage or collapse and is thus an indirect consequence and (b) the type and scale of building damage is very difficult to predict. To determine building damage, an intensity index (I DF) was created as the product of maximum expected flow depth d and the square of the maximum flow velocity v (I DF = dv 2). The I DF surrogates impact force and thus correlates with building damage. Four classes of building damage were considered ranging from nuisance flood/sedimentation damage to complete destruction. Sixty-six well-documented case studies in which damage, flow depth and flow velocity were recorded or could be estimated were selected through a search of the global literature, and I DF was plotted on a log scale against the associated damage. As expected, the individual damage classes overlap but are distinctly different in their respective distributions and group centroids. To apply this vulnerability model, flow velocity and flow depth need to be estimated for a given building location and I DF calculated. Using the existing database, a damage probability (P DF) can then be computed. P DF can be applied directly to estimate the likely insurance loss or associated loss of life. The model presented here should be updated with more case studies and is therefore made openly available to international researchers who can access it at .  相似文献   

20.
Based on the general physical nature of tsunami generation, it is established that it is an attribute of seismically hazardous areas and regions adjacent to large water reservoirs and is threatening to the population and infrastructure of the coastal zones. The main preconditions and possibilities for the occurrence of tsunami on Lake Baikal are considered: the information on earthquakes in the Baikal hollow during the instrumental-historical period (1724–2011) is generalized in the map of epicenters of shocks of magnitude M ⩾ 5 and histograms of the distribution of numbers of shocks with respect to magnitude. It is shown that the tsunami waves start forming on Baikal if the earthquake magnitude M is ≈5, but since a system of tsunami monitoring on Baikal is absent, it can be observed only during the strongest earthquakes of M > 7. The catastrophic Tsagan earthquake (1861, M ≈ 7.5) is given as an example. It happened near the eastern coast of Lake Baikal and caused a tsunami with people’s deaths.  相似文献   

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