Japan Earthquake Research Articles

Justification of Possible Casualty-Reduction Countermeasures Based on Global Tsunami Hazard Assessment for Tsunami-Prone Regions over the Past 400 Years

Tsunami hazards can be considered as multiregional in their impacts, as transoceanic waves can propagate beyond local areas, as evidenced in recent tsunami events, e.g., the 2004 Indian Ocean and 2011 Great East Japan tsunamis. However, in a single event, the characteristics of a tsunami (wave amplitude and arrival time) can differ from location to location, due to a myriad of reasons including distance from the source, bathymetry of the seafloor, and local effects. Tsunami countermeasures cannot be similarly applied globally. It is prudent to investigate tsunami hazard characteristics at a regional scale in order to evaluate suitable tsunami countermeasures. On this basis, approximately 300 major historical tsunamis have been reproduced in this study based on seismic records over the last 400 years. In this study, numerical analysis was performed to reproduce tsunami waveforms at each global tidal station, and numerical results were verified by comparing them with the 2011 Great East Japan tsunami record data. Non-structural tsunami countermeasures were proposed and selected for each region based on two main criteria – wave amplitudes and arrival times. Evaluation of selected countermeasures indicate that planning for evacuation processes (such as evacuation route mapping, signage and evacuation drills) are important in all situations. For local large tsunamis, evacuation drills are essential to ensure a community is well prepared for self-evacuation due to the short amount of time available for evacuation. Early warning systems were most effective where tsunamis are of large and distant origins. On the other hand, it would be more appropriate to invest in public alert systems for tsunamis of smaller magnitudes. Using these selection criteria, combinations of countermeasures were proposed for each region to focus their attention on, based on the simulated results of the historical tsunami events. The end-goal of this study is to inform decision-making processes and regional planning of tsunami disaster management.

Law and Disaster: Earthquake, Tsunami and Nuclear Meltdown in Japan by ShigenoriMatsui Published by Routledge, 2019, 284 pp., £96.00, hardback.

Law and Disaster: Earthquake, Tsunami and Nuclear Meltdown in Japan by ShigenoriMatsui Published by Routledge, 2019, 284 pp., £96.00, hardback.

A Generalization of the Stochastic Summation Scheme of Small Earthquakes to Simulate Strong Ground Motions

A generalization of the stochastic summation scheme of small earthquakes following a general form of the source spectrum (ω−n) model is developed to estimate the proper probability density functions for rupture propagation over the fault and to simulate site-specific strong ground motions in two independent stages. The probability density functions for rupture propagation are first developed for a single-corner-frequency source model, and then extended to multiplicative and additive double-corner-frequency source models to partially account for the effects of finite-fault rupture such as fault geometry, rise time, and rupture time on ground motions, and to better match observed Fourier amplitude spectra (FAS). The generalized two-stage stochastic summation scheme developed in this study can be used to simulate realistic strong-ground-motion time histories from small events, represented as empirical Green’s functions (EGFs), by specifying only two source parameters of the seismic moment and stress drop for a given site. The proposed two-stage stochastic summation schemes are tested using numerical examples following the theoretical source models as well as observed ground motions of the 2011 Mw 9.0 Tohoku earthquake in Japan and the 1994 Mw 6.7 Northridge earthquake in California to verify the applicability of the approach. Comparisons between the observed and simulated time histories for these two earthquakes, their response spectra, and FAS show satisfactory performance of the proposed approach for engineering purposes. The results of these comparisons indicate that the proposed stochastic summation of small events as EGFs can adequately replicate observed ground motions and evaluate uncertainties in ground motions with the generation of many time history realizations corresponding to a multitude of possible rupture processes . The proposed approach can also be used to generate multiple realistic acceleration time histories matched on average to the target response spectra for use in earthquake performance design, and to develop ground-motion models for low-seismicity regions, where there is a lack of recording of strong ground motions.

Structural Controls on Aftershock Distribution in Subduction Zones

The trench-parallel distribution of aftershocks generated after a major subduction-related earthquake does not conform to a fractal or normal distribution as expected but does appear to be spatially constrained by fractures on the subducting oceanic crust. Newly developed and very detailed 3D models of subducting plates (slabs) are combined with high-resolution topographic and bathymetric models of the crustal upper-plate and subducting lower-plate respectively to show how irregularities such as transform faults, spreading centers, fossil subduction zones and vertical tears form structural barriers to the spatial distribution of subduction zone aftershocks. When correctly constructed, slab models can now be used to better forecast the lateral (along-arc) extent of damaging aftershock swarms following large magnitude subduction-related earthquakes. Two earthquakes, (magnitude MW 7.8 in Vanuatu, 7th October 2009 (UTC) and magnitude MW 8.8 in southern Chile, 27th February 2010 (UTC)) were followed by hundreds of aftershocks, with many recording magnitudes over MW 6.5. Closer examination of these aftershocks and their spatial distribution indicate that they were unexpectedly confined to discrete sections of the subducting plate. It is revealed here that lithospheric-scale structures including fossil oceanic transform faults represent crustal and lithosphere-scale fractures in the crust that terminates the lateral spread of aftershocks. This contrasts with the predicted decrease in aftershock size and number with increasing distance from the epicenter referred to as the Omori (power law) distribution. This hypothesis addresses the paradigm that oceanic crust is a single, semi-continuous and uniform section of crust where the lateral distribution of earthquakes is described in terms of uniform rock mechanics. Additional research on the MW 9.0 earthquake in Japan (11th March 2011 (UTC)) and the MW 8.0 earthquake in the eastern Solomon Islands (6th February 2013 (UTC)) supports the aforementioned hypothesis. Using new techniques to help define the location of sub-plate boundaries, it is now possible to generate aftershock probability maps for some of the most seismically active subduction margins around the world.

We Heart Japan: Fan Citizenship and the Role of Institutions in the Response to Japanese Earthquakes

The 2011 Great East Japan earthquake and resulting tsunami that devastated the nation created a situation that, through the global flows of media content, necessitated a response from the international anime fan community. This response was shaped by the ethical framework of caring for the community. Performances of fan citizenship reflected this existing community value and the community’s identification with other fans and the people of Japan. Reflecting these identifications, fans took civic action in the form of the ethical modalities of donating money to relief efforts and critiquing community discourse that diverted attention from the disaster. Institutions, like the streaming service Crunchyroll, served to rhetorically define the ethical modalities at play in this context through their institutional role of amplifying performances of fan citizenship.

Electrolyte-Gated Organic Field-Effect Transistor for Ultra-Sensitive Cs Ion Sensor

A main purpose of this work is to develop a new ultra-highly sensitive sensor in particular for the detection of Cs+ ions in natural water. The radioactivity of Cs+ ions produced in nuclear power stations (NPSs) causes serious impact on the health condition of humans, as well as aquatic plants and animals. Therefore, it should be strictly controlled. However, a large amount of radioactive Cs+ had been distributed from Fukushima NPS due to the tragic accident after the great earthquake in Japan. Because of these reasons, the detection and monitoring of Cs+ ions in natural water are necessary. To tackle this issue, we developed an organic field-effect transistor (OFET)-based ion sensor. The sensor is composed of three main components: (1) organic semiconducting channel with high stability in working with natural water, (2) monolayer lipid membrane working as ultra-thin dielectric layer to allow low operating voltage and high sensitivity, and (3) novel calixarene-crown ether probe for high selectivity to Cs+ , which is grafted with lipid layer.Here, gate bias voltage is applied through electrolyte solution, in which the target ion and other competing ions are simultaneously contained. Once ion probes form metal-complex with Cs+, the electrical signal from the ion, the concentration of which is even on the ppb order, can be detected as a shift of threshold voltage. This is owing to the large electrical capacitance of monolayer lipid membrane. In comparison with other conventional methods like ICP-MS, our new sensor has many advantages: high sensitivity and selectivity, high-throughputs, integration and portability associated to real-time and on-site monitoring capabilities. In this presentation, we demonstrate a label-free sensor operation with the sensitivity of femtomolar (pg/l) concentrations of Cs+ ion with high selectivity.

A Sequentially Coupled Catchment‐Scale Numerical Model for Snowmelt‐Induced Soil Slope Instabilities

AbstractThe frequency of snowmelt‐induced soil slope instabilities is increasing in some seasonally cold regions because of climate change. Reliable hazard assessment and risk mitigation of snowmelt‐induced landslides require physically‐based prediction models. However, existing models either apply only at the slope scale or assume precipitation as the sole landslide trigger. In doing so, they neglect the complexity and coupled nature of the thermo‐hydro‐mechanical processes leading to slope instability in seasonally cold regions (such as snow accumulation and melting, infiltration and surface runoff, soil saturation, pore water pressure buildup and dissipation). Here, we present a spatially distributed and sequentially coupled numerical model to simulate snowmelt‐induced slope instabilities at the catchment scale. The model accounts for temperature‐dependent changes in the soil hydraulic behavior related to changes in water state by means of a routine implemented in a geographic information system. We verified the performance of the model using a case study of spring snowmelt‐induced soil slope failures that occurred after the 2004 Mid‐Niigata earthquake in Japan. Considering limitations and simplifications, the model was able to predict the triggering condition, magnitude, and spatial distribution of the snowmelt‐induced landslides with a satisfactory degree of accuracy. We believe that the robustness and simplicity of our numerical approach make it suitable for implementation in early warning systems.

Pediatric Peritoneal Dialysis During the Recent Earthquakes in Japan and Recommendations for Future Disaster Preparation

Pediatric Peritoneal Dialysis During the Recent Earthquakes in Japan and Recommendations for Future Disaster Preparation

A Damping Modification Factor Prediction Model for Horizontal Displacement Spectrum from Subduction Interface Earthquakes in Japan Accounting for Site Conditions

ABSTRACT This article presents a damping modification factor (DMF) model without source and path parameters for subduction interface earthquakes in Japan using a similar dataset as the one used in the Zhao, Liang, et al. (2016) study. Site effect was modeled by site classes based on site periods. DMF models were constructed using the spectra for 13 damping ratios at 34 spectral periods. The DMF values can be calculated in a damping ratio range of 1%–30% and in a spectral period range of 0.03–5.0 s. The effect of damping ratios was modeled by a simple quadratic function of the damping ratios in the logarithm scale, and the effect of the spectral period was modeled by a simple fourth-order polynomial of the spectral period also in the logarithm scale. The DMF value is 1.0 at a spectral period of ≤0.02 s . At long periods >5.0 s, the DMFs for different damping ratios appear to converge to 1.0, satisfying the condition of constant displacement spectrum at long periods. For an extrapolation to >5.0 s for a damping ratio <5%, DMF=1.0 can be selected when DMF<1.0; for a damping ratio >5%, DMF=1.0 can be selected when DMF>1.0. For a damping ratio <5%, all standard deviations decrease linearly with increasing damping ratios in the logarithm scale; for a damping ratio >5%, all standard deviations increase linearly with increasing damping ratios in the logarithm scale. A smoothed displacement spectrum useful for engineering designs can be obtained by scaling the spectrum from Zhao, Liang, et al. (2016). The DMF values from this study are close to those of the published models at some spectral periods. The residual distribution suggests that DMFs are functions of earthquake source and path parameters.

Improvement of Gasification Efficiency with Consideration for Microwave Input Power on Biogas Reformulation by Microwave Plasma Assisted Combustion

Extended In recent years, the effective use of low grade fossil fuel and the diversity of fuels are required due to the exhaustion of fossil fuels, global warming and the nuclear accident caused by the Tohoku earthquake in Japan. The studies of brown coal, biomass, biofuel, etc. are being conducted to expand the use of these fuels throughout the world. We have paid attention to biogas among such low grade fuels. Biogas is a carbon neutral fuel to be generated from garbage, livestock manure, sewage sludge, etc. CO2 emitted by its combustion is not converted to greenhouse gases. On the other hand, biogas is primarily composed of 60% CH4 and 40% CO2, and has a low calorific value. Low calorific value does not make biogas easy to apply to a conventional energy utility system. To utilize biogas, it is necessary to develop the combustion promotion technology of biogas or upgrade biogas.

Factors Affecting South Korean Disaster Officials’ Readiness to Facilitate Public Participation in Disaster Management Using Smart Technologies

As the frequency and intensity of catastrophic disasters increase, there is widespread public sentiment that government capacity for disaster response and recovery is fundamentally limited, and that the involvement of civil society and the private sector is ever more vital. That is, in order to strengthen national disaster response capacity, governments need to build disaster systems that are more participatory and function through the channels of civil society, rather than continuing themselves to bear sole responsibility for these “wicked problems.” With the advancement of smart mobile technology and social media, government and society as a whole have been called upon to apply these new information and communication technologies to address the current shortcomings of government-led disaster management. As illustrated in such catastrophic disasters as the 2011 Tohoku earthquake and tsunami in Japan, the 2010 Haitian earthquake, and Hurricane Katrina in the United States in 2005, the realization of participatory potential of smart technologies for better disaster response has enabled citizen participation via new smart technologies during disasters and resulted in positive impact on the management of such disasters. In this context, this study focuses on the South Korean context, and aims to analyze Korean government officials’ readiness for public participation using smart technologies. On this basis, it aims to offer policy suggestions aimed at promoting smart technology–enabled citizen participation. For this purpose, it proposes a particular model, termed SMART (System, Motivation, Ability, Response, and Technology).

Geological features of landslides caused by the 2018 Hokkaido Eastern Iburi Earthquake in Japan

Abstract Before dawn on 6 September 2018, a powerful earthquake with a Japan Meteorological Agency magnitude ( M j ) of 6.7 hit central Hokkaido, causing more than 6000 landslides. As human damage, 36 of the 44 fatalities from the earthquake were from earthslides in Atsuma Town. Most slope movements were shallow earthslides of mantle-bedded tephra and soil layers, but some were deep rockslides involving basement rocks such as shale and mudstone of Miocene. Although the shallow earthslides were easily distinguishable in photos from satellites or airplane, the rockslides were more difficult to identify owing to their vegetation. Based on the quick interpretation of a high-resolution (0.5 m horizontal resolution) shaded relief map made from digital elevation model data by airborne laser survey and supplemental field surveys, we effectively identified 259 rockslides (196 certain ones and 63 possible ones) in Atsuma and Mukawa towns under newly invented identification criteria based on the scarp depth and positional relation between scarp and ridge topography. It was revealed that most rockslides were distributed within 10 km from the epicentre, while earthslides were distributed until 20 km north of the epicentre, and they seemed to be controlled by the thickness of mantle-bedded tephra and the soil layer. We also identified many traces of past rockslides and earthslides. The results show the possibilities for effective measurement of slope by clarifying the landslide distribution both this earthquake and past ones using high-resolution digital elevation model data.

Аssessment of a landslide hazard taking into account seismic impact

Landslides represent a major threat to human life, constructed facilities, infrastructure and natural en-vironment in many regions of the world. During the decade 2000-2009, natural disasters caused nearly one million facilities, affecting nearly 2.5 billion people across the globe. The landslide frequency of about 20 major events per year in Europe is the highest compared to floods, earthquakes and cyclones. All 50 States and the U.S. territories are subjected to landslides and other ground-failure problems; 36 States have changed (from moderate to highly) the severe landslide hazards. Landslides in the USA constitute a serious hazard. They cause the substantial human and financial losses, estimated as 25…50 deaths annually and to cost approximately $ 1 billion to $ 3 billion per year.Activation of seismic activity in Vrancea area, the Black Sea region and in the whole world has led to increase level of seismic hazard in Ukraine and in the finally growth relevant provoke factors of landslide movement. Whole Ukraine, not only as earlier considered Carpathian and Crimean regions, is now an area with high potential risk of future huge earthquakes. "... Іn areas with reduced characteristics of soil (frequent flooding, landslides, etc.) can be observed 7–8-magnitude effects", – said the deputy director of the Institute of Geophysics of the National Academy of Science of Ukraine O. Kendzera. Before the Japanese earthquake (11.03.2011) considered in the world that at 9-magnitude earthquake acceleration of ground can be maximum of 0,4 g. "But the Japanese catastrophy showed whole 2,7 g. This led to much more damage than expected. This means that now is the time when we must to correct all parameters of earthquakes," – says S. Ohasyan, the director of the Armenian Institute of Geophysics and Engineering Seismology. And О. Kendzera added: "... we must to correct initial data, that designers will use in the projects of buildings and construction".In the early stages of the design of anti-slip structures for operational approximate calculations of the slope and shear pressure coefficient, a program is required that has the following properties: ease of use; graphical, human-oriented interface; is based on tried and tested mathematical methods; endowed with a pleasant form of presentation of the results of calculations (graphical and tabular forms); speed of calculations, etc. LANDSLIDE meets these requirements. An example of taking into account seismic factors when calculating slopes according to the second group of boundary states is considering. A typical calculation using the LANDSLIDE program is given. Тhe slope stability coefficients was calculated using the LANDSLIP program by Maslow-Berer and Shakhutnyants methods. By using the limit equilibrium theory, the mechanism of “unloading the accumulated tension” in the slope massive during an earthquake is described.

AssessBlocks

Natural disasters cause long-lasting mental health problems such as PTSD in children. Following the 2011 Earthquake and Tsunami in Japan, we witnessed a shift of toy block play behavior in young children who suffered from stress after the disaster. The behavior reflected their emotional responses to the traumatic event. In this paper, we explore the feasibility of using data captured from block-play to assess children's stress after a major natural disaster. We prototyped sets of sensor-embedded toy blocks, AssessBlocks, that automate quantitative play data acquisition. During a three-year period, the blocks were dispatched to fifty-two post-disaster children. Within a free play session, we captured block features, a child's playing behavior, and stress evaluated by several methods. The result from our analysis reveal correlations between block play features and stress measurements and show initial promise of using the effectiveness of using AssessBlocks to assess children's stress after a disaster. We provide detailed insights into the potential as well as the challenges of our approach and unique conditions. From these insights we summarize guidelines for future research in automated play assessment systems that support children's mental health.

High-Frequency Spectral Decay Characteristics of Seismic Records of Inland Crustal Earthquakes in Japan: Evaluation of the fmax and κ Models

ABSTRACTWe examined high-frequency spectral decay characteristics of ground motions for inland crustal earthquakes in Japan, which are important in strong ground motion predictions. We examined 105 earthquakes (Mw 3.3–7.1), including seven large earthquakes (Mw 5.9–7.1). Spectral decay characteristics were accurately evaluated assuming the ω-squared source model and using two approaches: the fmax model (commonly used in Japan), described by the cutoff frequency fmax and the power coefficient of spectral decay s, and the κ model (commonly used in worldwide), the exponential spectral decay model, described by the parameter κ and the specific frequency fE at which a spectrum starts to decrease linearly with increasing frequency in log–linear space. For large earthquakes, we estimated fmax to range from 6.5 to 9.9 Hz and s from 0.78 to 1.60 in the fmax model, and κ to range from 0.014 to 0.051 s and fE from 2 to 4.5 Hz in the κ model. In both approaches, we found that the spectral decay characteristics are regionally dependent. fmax in the fmax model and fE in the κ model tended to be smaller for large earthquakes than for moderate and small earthquakes, clearly demonstrating a seismic moment dependency. We confirmed positive correlations between equivalent parameters of the two approaches, that is, between s and κ and between fmax and fE. Moreover, we found that both approaches are appropriate for evaluating spectral decay characteristics, as long as the spectral decay parameters are appropriately evaluated by comparison with observed spectra. We examined the effects of the spectral decay characteristics on strong ground motion predictions, and demonstrated that simulated motions corrected using the fmax model and those corrected using the κ model are almost the same. The results presented in this article contribute to improving predictions of high-frequency strong ground motion.

Numerical investigation of tsunami wave impacts on different coastal bridge decks using immersed boundary method

Due to the strong interaction between the bridges and the extreme waves generated by hurricanes and tsunamis, many coastal bridges were damaged in the past few decades. In this study, in order to investigate the effect of the extreme wave on a bridge, tsunami-like wave generated based on record in the Iwate station during 2011 Japan tsunami event instead of solitary wave is employed to impinge on the bridge with or without air vent. According to the Computational Fluid Dynamics (CFD) theory with a Volume of Fluid (VOF) interface tracking approach, a Numerical Wave Tank (NWT) is developed, in which the Immersed Boundary (IB) method is referred to simulate fluid and structure interaction. The model is calibrated with the experiment. In this numerical tank, the effects of tsunami-like waves with different prominent conditions including wave height and submersion depth on the bridges are studied. Besides, the efficiency of air vent in reducing the hydrodynamic load is also discussed. The results indicate that when the tsunami-like wave overtops the bridges, a noticeable overtopping, where the flow injects into the water fiercely and the whole flow field is very chaotic, is observed. The vertical forces on the bridges are larger than the horizontal forces, leading to many decks to collapse between two piers with small lateral displacement after the hurricanes and tsunamis. After the tsunami-like wave passes over the bridge, the oscillation of the residual wave causes the load oscillation of the bridge. The position of the bridge relative to the initial sea level has a serious impact on the forces on the bridge when the tsunami-like wave passes through it. With the increase of the wave height, the interaction intensity between the tsunami-like wave and the bridge is enhanced and the forces on the bridge also increase, but the effect duration reduces. After the air vent is installed, air vent can reduce the forces on the bridge and improve the efficiency of the bridge protection.

Effects of region-specific shocks on labor market tightness and matching efficiency: evidence from the 2011 Tohoku Earthquake in Japan

This paper examines whether region-specific shocks alter regional labor market tightness and matching efficiencies. We adopt the Great East Japan Earthquake of March 2011, which caused a tsunami and nuclear disaster, as a region-specific shock. We find that an increase in labor market tightness, namely, labor shortage, occurs in the damaged regions after the disaster. Matching efficiencies in the damaged regions deteriorate, suggesting that the composition of unemployment and vacancies changes, leading to higher search frictions. Such nature has spatial spillover effects because of the widespread increase in demand for reconstruction and out-migration from the damaged regions.

A Database of Digitized and Analog Seismograms of Historical Earthquakes in Japan

AbstractSeismic and tsunami instrumental observations by seismographs and tide gauges began in Japan in 1875; hence, many analog records of earthquakes and tsunamis are stored at various universities and institutions throughout the country. Re-examination of historical records using modern waveform analysis methods, high-performance computing, and current knowledge on seismic velocity structure is expected to produce new results and interpretations of the mechanism of large earthquakes and tsunamis, leading to improved seismic disaster mitigation practices. However, such work requires extensive effort and skills for the digitization of the analog waveforms recorded on papers. To conveniently use the analog seismograms, we currently construct a database of digitized historical records and seismogram image copies of major earthquakes that occurred in Japan (e.g., the 1923 Kanto, 1944 Tonankai, and 1946 Nankai earthquakes). The data can be searched in this database by event, station, and seismograph names. Users can obtain the instrumental response and station information, if available, in addition to the digitized data. We plan to open this database to the public in a few years via the National Museum of Nature and Science and the Earthquake Research Institute of the University of Tokyo. The database on the museum website will be fundamental for outreach activity of seismology for the general public, and the information contained in the database will be useful in various fields such as seismology or earthquake engineering.

Did the 2008 Wenchuan earthquake trigger a change in the conduct of research on seismic risk?

This study aims to address how the 2008 Wenchuan Earthquake influenced knowledge generation and diffusion compared to the research stemming from the 1989 Loma Prieta Earthquake in the United States and the 1995 Hanshin Awaji Earthquake in Japan, for the three countries are exposed to high seismic risk. The findings show that (1) regarding research quantity, the influence of the Wenchuan Earthquake on disaster-related knowledge generation is just beginning compared with the gradual decreases in research on the other earthquakes; (2) regarding disciplinary development, the proportion of studies relating to the Wenchuan Earthquake in natural sciences and engineering technology is gradually decreasing, while the proportion of studies in medical science, social sciences and economics is increasing; (3) the quantity of earthquake-related studies is not solely related to the influence of a specific disaster but associated with the national financial support offered by the affected country. One reason why China experiences the high research output is that Chinese national finance strongly supports such research, similar to the United States and Japan. This phenomenon corresponds with the fact that the major research institutions in China are national institutions rather than universities. Finally, (4) interdisciplinary research on the Wenchuan Earthquake mainly involves interactions between natural sciences and engineering technology. Interactions between other disciplines need to be enhanced. Thus, this research argues that, although disaster knowledge generation and diffusion is imbalanced, the multidimensional nature of earthquakes has been recognized in the literature.

Hierarchical Bayesian Modeling of Post-Earthquake Ignition Probabilities Considering Inter-Earthquake Heterogeneity.

Post-earthquake fires are high-consequence events with extensive damage potential. They are also low-frequency events, so their nature remains underinvestigated. One difficulty in modeling post-earthquake ignition probabilities is reducing the model uncertainty attributed to the scarce source data. The data scarcity problem has been resolved by pooling the data indiscriminately collected from multiple earthquakes. However, this approach neglects the inter-earthquake heterogeneity in the regional and seasonal characteristics, which is indispensable for risk assessment of future post-earthquake fires. Thus, the present study analyzes the post-earthquake ignition probabilities of five major earthquakes in Japan from 1995 to 2016 (1995 Kobe, 2003 Tokachi-oki, 2004 Niigata-Chuetsu, 2011 Tohoku, and 2016 Kumamoto earthquakes) by a hierarchical Bayesian approach. As the ignition causes of earthquakes share a certain commonality, common prior distributions were assigned to the parameters, and samples were drawn from the target posterior distribution of the parameters by a Markov chain Monte Carlo simulation. The results of the hierarchical model were comparatively analyzed with those of pooled and independent models. Although the pooled and hierarchical models were both robust in comparison with the independent model, the pooled model underestimated the ignition probabilities of earthquakes with few data samples. Among the tested models, the hierarchical model was least affected by the source-to-source variability in the data. The heterogeneity of post-earthquake ignitions with different regional and seasonal characteristics has long been desired in the modeling of post-earthquake ignition probabilities but has not been properly considered in the existing approaches. The presented hierarchical Bayesian approach provides a systematic and rational framework to effectively cope with this problem, which consequently enhances the statistical reliability and stability of estimating post-earthquake ignition probabilities.