Earthquake fatalities and potency (original) (raw)
Related papers
2016
Earthquakes have caused over 2.3 million fatalities since 1900. They have also been responsible for the equivalent loss of over $1.25 trillion USD of human capital derived economic effects in total across the globe from casualties. However, a key consideration for decision-makers implementing earthquake sensitive design in different countries around the world is the risk of an earthquake death compared to other types of deaths in their country. Additionally, the role of life safety is increasing, with risk-based earthquake resistant codes becoming more commonplace. On an annualised level, very few countries show earthquakes to be one of the highest probability methods for death. However, in particular years with large events these totals can easily exceed the total death count for a particular country. An example of this is Haiti, with the equivalent earthquake death rate in 2010 exceeding the total death rate in the country due to all other causes. In this study, various methods of...
Trends in the Casualty Ratio of Injured to Fatalities in Earthquakes
The worldwide ratio of injured to fatalities in earthquakes, R = Inj/Fat, has increased over time. This shows that it is more likely by approximately a factor of 2 that a person survives an earthquake today than 50 years ago. However, any meaningful analysis of R requires (as a minimum) separation by type of country and by location of epicentres (land or offshore). R in earthquakes beneath land is typically half of that for events offshore. R in the industrialised world is about two to three times larger than in the developing world. The countries that have made the greatest progress in protecting their population are Japan and China. Countries where R has not increased with time include Iran, Turkey, and Greece. The basic trends are clear, but the data sets for some individual countries are too small for the averages to be considered firm. We propose to use R to adjust the casualty matrices for estimation of human losses due to earthquakes worldwide.
Urban Earthquake Fatalities: A Safer World, or Worse to Come?
Seismological Research Letters, 2004
The global fatality count from earthquakes continues to rise. This has occurred despite the adoption of earthquake resistant building codes in most countries where damaging earthquakes have historically caused loss of life. In the past five centuries the global deathtoll from earthquakes has averaged 100,000/year, a rate that is dominated by large infrequent disasters, mostly in the developing nations. Though an increased fatality rate might be expected from the steady increase in global population , recent urban growth has been accompanied by a decline in the fatality rate as expressed as a percentage of instantaneous population. It is tempting to attribute this observation to the application of earthquake resistant construction code in new city construction. A more sinister interpretation, however, is that the apparent decline in risk is caused by the short exposure time (50 years) of the world's recently increased population to earthquakes with recurrence intervals of the order of centuries. Future extreme earthquake disasters in some of the world's megacities may arrest, or reverse, the current trend.
Earthquake faulting and human life loss
The aim of this paper is the investigation on the distribution of the loss of human lives in relation to the occurrence of earthquake faults during recent earthquakes that took place in urban centres. The study cases were the three shallow, near-field earthquakes in Kobe (Japan, 17 Jan. 1995), Dinar (Turkey, 1 Oct. 1995) and Egio (Greece, 15 June 1995). The intensities exceeded locally the X grade of E.M.S.-1992 and there was surficial occurrence of earthquake fractures. The distribution of victims was plotted against the fault trace and the processing of data involved the elimination of the consequences of the related surficial earthquake effects, as liquefaction and landslides. Important part in the mortality distribution is played by the fires that broke out, a factor that was also taken into consideration. The resulting charts (mortality plotted against the distance from the fault trace) present a bell-shaped distribution around the fault trace. The distribution width has a maximum of 4 km (Dinar earthquake) and becomes almost zero, virtually coinciding with the fault trace at the case of Egio earthquake. On the other hand, the deaths that are due to the earthquake-related effects and fires are randomly distributed, in relation to the distance from the fault trace. Therefore, as the occurrence of active faults near or through urban centres constitutes a major risk for human life loss in case of earthquakes, the localisation and the systematic study of active faults is capable of significantly reducing the number of victims in a potential earthquake event.
Earth, Planets and Space, 2016
Large Himalayan earthquakes expose rapidly growing populations of millions of people to high levels of seismic hazards, in particular in northeast India and Nepal. Calibrating vulnerability models specific to this region of the world is therefore crucial to the development of reliable mitigation measures. Here, we reevaluate the >15,700 casualties (8500 in Nepal and 7200 in India) from the M w ~8.2, 1934, Bihar-Nepal earthquake and calculate the fatality rates for this earthquake using an estimation of the population derived from two census held in 1921 and 1942. Values reach 0.7-1 % in the epicentral region, located in eastern Nepal, and 2-5 % in the urban areas of the Kathmandu valley. Assuming a constant vulnerability, we obtain, if the same earthquake would have repeated in 2011, fatalities of 33,000 in Nepal and 50,000 in India. Fast-growing population in India indeed must unavoidably lead to increased levels of casualty compared with Nepal, where the population growth is smaller. Aside from that probably robust fact, extrapolations have to be taken with great caution. Among other effects, building and life vulnerability could depend on population concentration and evolution of construction methods. Indeed, fatalities of the April 25, 2015, M w 7.8 Gorkha earthquake indicated on average a reduction in building vulnerability in urban areas, while rural areas remained highly vulnerable. While effective scaling laws, function of the building stock, seem to describe these differences adequately, vulnerability in the case of an M w >8.2 earthquake remains largely unknown. Further research should be carried out urgently so that better prevention strategies can be implemented and building codes reevaluated on, adequately combining detailed ancient and modern data.
Impact of Earthquake Magnitude on Lives Lost During Shock
Indonesian Journal of Environmental Management and Sustainability, 2021
Earthquake is one of the catastrophic natural disasters in the history of mankind which consumed hundreds and thousands of human lives every year. Attitude of man in handling natural environment make earthquakes inevitable. The study was design to examine the impact of earthquake magnitude on lives loss during earthquakes. Data adopted for study are solely secondary data which include; journals, textbooks, published and unpublished document. Sampled was derived using purposive sampling techniques, earthquakes that lives were loss during their occurrence characterized with 6.0Mw and above were selected as sample. Regression analysis, maps QGIS software, tables and graphs were used for data analysis in study. The result of the research indicate a fair relation among studied variables. Figure 1 Multiple R=0.073, Figure multiple=0.454 and Figure multiple R=0.452. Multiple R determine the nature of relation between study variables, the close the value of multiple R is to 1 the strong the relationship. Which means fair relationship exist between earthquake magnitudes and live loss during 1990-2019 earthquakes. And R2 result Figure 1, 1% of the lives lost during earthquakes 1990-1999 are determine by earthquake magnitude, R2 result in Figure 4 indicated 21% of the lives lost during earthquakes 2000-2009 are determine by earthquake magnitude and R2 result in Figure 6 demonstrate 20% of the lives loss during earthquakes 2010-2019 are determine by earthquake magnitudes. Significant F results are Figure 1 significant F =0.613, Figure 4 significant F=0.001 and Figure 6 significant F=0.0004. Two out of the three significant F result indicated that the result of the research is reliable while one result indicated that the result is less reliable. However, the result of the research signifies, other factors such as population density of the area where the earthquakes occur, the geological structure of the areas where the earthquake take place, the time at which the earthquake occur i.e. night or during daylight and precipitation also trigger earthquakes in a few kilometer depth influence number lives lost during earthquake.
Global occurrence and impact of small-to-medium magnitude earthquakes: a statistical analysis
Bulletin of Earthquake Engineering
Despite their much smaller individual contribution to the global counts of casualties and damage than their larger counterparts, earthquakes with moment magnitudes M w in the range 4.0-5.5 may dominate seismic hazard and risk in areas of low overall seismicity, a statement that is particularly true for regions where anthropogenically-induced earthquakes are predominant. With the risk posed by these earthquakes causing increasing alarm in certain areas of the globe, it is of interest to determine what proportion of earthquakes in this magnitude range that occur sufficiently close to population or the built environment do actually result in damage and/or casualties. For this purpose, a global catalogue of potentially damaging events-that is, earthquakes deemed as potentially capable of causing damage or casualties based on a series of pre-defined criteria-has been generated and contrasted against a database of reportedly damaging small-to-medium earthquakes compiled in parallel to this work. This paper discusses the criteria and methodology followed to define such a set of potentially damaging events, from the issues inherent to earthquake catalogue compilation to the definition of criteria to establish how much potential exposure is sufficient to consider each earthquake a threat. The resulting statistics show that, on average, around 2% of all potentially-damaging shocks were actually reported as damaging, though the proportion varies significantly in time as a consequence of the impact of accessibility to data on damage and seismicity in general. Inspection of the years believed to be more complete suggests that a value of around 4-5% might be a more realistic figure.