Academic literature on the topic 'Earthquake Scenario'

Predicting the outcomes of earthquakes before they occur is one of the fundamental components of modern disaster management. Loss estimation analyses have an important place at the assessment stage of earthquakes and in estimation of losses that earthquakes may lead to. With these analyses, it is possible to access information that is relevant to potential damages and losses. In this paper, loss estimation analyses were carried out by using the earthquake scenario which foresaw a previous earthquake that was experienced in an around Kırşehir which is seismically active and located in the Central Anatolia Region in Turkey. The 1938 Akpınar earthquake which occurred in and around the province of Kırşehir was taken into consideration as an earthquak escenario, and loss estimation analyses were conducted for this earthquake scenario. In this paper, significant contributions will be made for preparation of an earthquake master plan and risk management plan for Kırşehir. Besides, studies on reduction of earthquake losses in the region may utilise these results.

Natural disaster cannot be stopped but its effect can be minimized or avoided by adopting technology and necessary human adjustment. Earthquake is a natural event which occurs without early warning signs. Computer based earthquake scenarios are used worldwide to describe and estimate the damage from potential earthquakes. The current study is an attempt to explore potential risk with respect to physical infrastructure and assess modeled and actual physical damage and human loss caused by different earthquake scenario and actual 2015 earthquake event in Thecho of Kathmandu valley. The earthquake scenario is based on two nearest fault lines. Risk Assessment Tools for the Diagnosis of Urban Seismic Risk (RADIUS) method has been applied for estimation of potential building damage and casualties..The research has adopted integrated approach using secondary and primary data sources such as field observation, key informant survey and building survey through purposive random sampling.The study found that potential building damage estimated by RADIUS for Gorkha 2015 earthquake scenario and North-west (Khokana) are lower than the actual post-earthquake assessment whereas North earthquake scenario resulted higher loss. Actual damage caused by 2015 earthquake compared to modeled damage from RADIUS is found higher because additional damaged were made by successive aftershocks. Spatial distribution of potential building damage for earthquake scenarios and actual 2015 earthquake event is also variable. North-Nuwakot Earthquake Scenario resulted more hazardous than the North-Khokana scenario though the location of epicenter is relatively farther with high intensity. The study concluded that though earthquake occurrence and disaster is still less predictable risk assessment tools like RADIUS and mitigation measures based on such is important for reducing risk of earthquake disaster.The Geographical Journal of NepalVol. 11: 127-136, 2018

This paper describes a method of extracting the relation between the ground-motion characteristics of each area and a seismic source model, based on ground-motion simulation data output in planar form for many earthquake scenarios, and the construction of a parallel distributed processing system where this method is implemented. The extraction is realized using two-stage clustering. In the first stage, the ground-motion indices and scenario parameters are used as input data to cluster the earthquake scenarios within each evaluation mesh. In the second stage, the meshes are clustered based on the similarity of earthquake-scenario clustering. Because the mesh clusters can be correlated to the geographical space, it is possible to extract the relation between the ground-motion characteristics of each area and the scenario parameters by examining the relation between the mesh clusters and scenario clusters obtained by the two-stage clustering. The results are displayed visually; they are saved as GeoTIFF image files. The system was applied to the long-period ground-motion simulation data for hypothetical megathrust earthquakes in the Nankai Trough. This confirmed that the relation between the extracted ground-motion characteristics of each area and scenario parameters is in agreement with the results of ground-motion simulations.

Abstract We develop ensemble ShakeMaps for various magnitude 9 (M 9) earthquakes on the Cascadia megathrust. Ground-shaking estimates are based on 30 M 9 Cascadia earthquake scenarios, which were selected using a logic-tree approach that varied the hypocenter location, down-dip rupture limit, slip distribution, and location of strong-motion-generating subevents. In a previous work, Frankel et al. (2018) used a hybrid approach (i.e., 3D deterministic simulations for frequencies <1 Hz and stochastic synthetics for frequencies >1 Hz) and uniform site amplification factors to create broadband seismograms from this set of 30 earthquake scenarios. Here, we expand on this work by computing site-specific amplification factors for the Pacific Northwest and applying these factors to the ground-motion estimates derived from Frankel et al. (2018). In addition, we use empirical ground-motion models (GMMs) to expand the ground-shaking estimates beyond the original model extent of Frankel et al. (2018) to cover all of Washington State, Oregon, northern California, and southern British Columbia to facilitate the use of these ensemble ShakeMaps in region-wide risk assessments and scenario planning exercises. Using this updated set of 30 M 9 Cascadia earthquake scenarios, we present ensemble ShakeMaps for the median, 2nd, 16th, 84th, and 98th percentile ground-motion intensity measures. Whereas traditional scenario ShakeMaps are based on a single hypothetical earthquake rupture, our ensemble ShakeMaps take advantage of a logic-tree approach to estimating ground motions from multiple earthquake rupture scenarios. In addition, 3D earthquake simulations capture important features such as strong ground-motion amplification in the Pacific Northwest’s sedimentary basins, which are not well represented in the empirical GMMs that compose traditional scenario ShakeMaps. Overall, our results highlight the importance of strong-motion-generating subevents for coastal sites, as well as the amplification of long-period ground shaking in deep sedimentary basins, compared with previous scenario ShakeMaps for Cascadia.

A clustering method that classifies earthquake scenarios and the local area on the basis of similarities in the spatial distribution of ground motion was applied to long-period ground-motion data computed by a seismic wave propagation simulation. The simulation utilized a large number of seismic source models and a three-dimensional velocity structure model in which megathrust earthquakes in the Sagami Trough were assumed. The relationship between the clusters, earthquake scenario parameters, and the velocity structure model was examined. In addition, the relationship between the earthquake scenario clusters for a case in which actual strong-motion observation points were treated as a mesh and those for a case in which an entire set of meshes was investigated, and a spatial interpolation method that estimated a ground-motion distribution from strong-motion observation data was examined.

We developed a clustering method combining principal component analysis and the k-means algorithm, which classifies earthquake scenarios based on the similarity of the spatial distribution of earthquake ground-motion simulation data generated for many earthquake scenarios, and applied it to long-period ground-motion simulation data for Nankai Trough megathrust earthquake scenarios. Values for peak ground velocity and relative velocity response at approximately 80,000 locations in 369 earthquake scenarios were represented by 15 principal components each, and earthquake scenarios were categorized into 30 clusters. In addition, based on clustering results, we determined that extracting relationships between principal components and scenario parameters is possible. Furthermore, by utilizing these relationships, it may be possible to easily estimate the approximate ground-motion distribution from the principal components of arbitrary sets of scenario parameters.

Quantitative probability has been computed for the tsunami hazard posed by earthquakes from the Manila Trench, which has been regarded as a huge threat in the South China Sea. This study provides a spatial distribution of the tsunami hazard covering the affected area with a spatial resolution of 0.1° for disaster prevention of islands and continental coasts. The quantitative probability of the tsunami hazard is computed by an efficient model, which can realize a large amount of potential tsunami scenarios analysis in order to consider the randomness and uncertainty in earthquake magnitude, source location and focal depth. In the model, for each potential tsunami scenario, the occurrence probability of the corresponding earthquake and the intensity of tsunami waves at each target location are computed. The occurrence probability of each scenario is estimated based on the historical earthquake records. Then, the subsequent tsunami caused by each scenario is computed using a new, efficient approach, instead of direct simulation using an ocean dynamics model. A total of 1,380,000 scenarios are computed in order to obtain a stable statistical result. Based on the results, the spatial distribution of the tsunami hazard is discussed and high-hazard regions along the coast have been identified.

The approaches necessary for estimating earthquake effects on railroads are different for developing design criteria or post-earthquake response policies and for developing railroad damage scenarios. In developing design criteria or post-earthquake response policies, the probability of ground motions exceeding a particular level is a primary concern. Developing damage scenarios, on the other hand, involves describing hypothetical effects for assumed ground motions. The identification of potential problems is the greatest benefit of disaster scenario development to railroads. Developing the Great Southern California ShakeOut Scenario revealed areas in which advance planning and arrangements by the affected railroads could reduce delays in repair work or improve the efficiency of operation during recovery. These include arranging emergency waivers for permits and similar governmental requirements, developing arrangements to accommodate earthquake-related conflicts between commuter and freight operations, advance arrangements for emergency use of helicopters, and physically securing equipment at the San Bernardino dispatching center to reduce damage.

Abstract. A rapid growth of population, intensive civil and industrial building, land and water instabilities (e.g. landslides, significant underground water level fluctuations), and the lack of public awareness regarding seismic hazard contribute to the increase of vulnerability of Baku (the capital city of the Republic of Azerbaijan) to earthquakes. In this study, we assess an earthquake risk in the city determined as a convolution of seismic hazard (in terms of the surface peak ground acceleration, PGA), vulnerability (due to building construction fragility, population features, the gross domestic product per capita, and landslide's occurrence), and exposure of infrastructure and critical facilities. The earthquake risk assessment provides useful information to identify the factors influencing the risk. A deterministic seismic hazard for Baku is analysed for four earthquake scenarios: near, far, local, and extreme events. The seismic hazard models demonstrate the level of ground shaking in the city: PGA high values are predicted in the southern coastal and north-eastern parts of the city and in some parts of the downtown. The PGA attains its maximal values for the local and extreme earthquake scenarios. We show that the quality of buildings and the probability of their damage, the distribution of urban population, exposure, and the pattern of peak ground acceleration contribute to the seismic risk, meanwhile the vulnerability factors play a more prominent role for all earthquake scenarios. Our results can allow elaborating strategic countermeasure plans for the earthquake risk mitigation in the Baku city.

In the framework of the "SEISIMPACT-THES" project (Koutoupes et al., 2004; Savvaidis et al., 2004) a GIS database has been designed to include information on a wide range of components related to seismic risk within the broader area of the prefecture of Thessaloniki. One of these components refers to the distribution of strong ground motion produced by large earthquakes and the ability of a potential future user of the database to retrieve information regarding the distribution of strong ground motion from past destructive earthquakes in the area of Thessaloniki, as well as relative information for realistic future scenario earthquakes in the same area. The selection of future scenario earthquakes that may affect this urban region of interest is based on a combined review of historical data, previous probabilistic and deterministic hazard assessments, seismotectonic and microseismicity studies, relocated seismicity in northern Greece and the experience gained from worldwide research. In this study we present the results from hypothetical rupture of one fault that is located at the suburbs of the city, the Asvestochori fault. Empirical relations applicable to Greece (Papazachos & Papazachou 2003), as well as seismicity information are combined to determine the dimensions of the scenario earthquake source. Strong ground motion for the selected scenario is simulated using the stochastic method for finite faults (Beresnev and Atkinson, 1997). Uncertainties due to unknown parameters such as the rupture initiation point and the distribution of slip on the fault plane are taken into account by examining a large number of random scenarios. The average values from these multiple scenarios are then used to compile maps of strong ground motion parameters (e.g. peak ground acceleration and spectral acceleration). Although the examined scenario earthquake is moderate in size (Mw 5.2), the level of the resulting strong ground motion parameters is indicative of the potential destructiveness of the examined source. Due to the simplicity in the underlying assumptions of the stochastic method, the results of this study are a first-order approximation to the problem of defining expected shaking in the wider area of Thessaloniki. Other strong motion simulation methods of more deterministic character will also be applied for the same purpose in the framework of the SEISIMPACT-THES project.