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From a 2006 analysis.
Lots of interesting graphics. Shaking at ground level depends not only on magnitude and shallowness of the quake, but also depends on how the waves reflect and refract, how the waves interfere, and the depth of soil (deep soil, typically near rivers, shakes like jelly; solid rock shakes much less).
http://rsta.royalsocietypublishing.o...1845/1965.full
Human, structural and financial consequences of a large Tokyo earthquake
The Cabinet Office of the Japanese government recently issued a risk assessment for large Tokyo earthquakes (Central Disaster Management Council 2005). They considered an M=7.3 earthquake beneath Tokyo, similar to the 1855 Ansei-Edo shock. The 240 000–840 000 destroyed buildings in their estimate depend strongly on wind speed and time of day, because high winds spread fire and rush hour exposes people to falling objects. If an M=7.3 earthquake struck at 18.00 in 15 m s−1 (33 miles h−1) winds, the Cabinet Office estimates 11 000 deaths, 210 000 wounded and 96 million tons of wreckage. About 57% of the deaths and 77% of the housing collapses are attributable to fire, and 28% of deaths and 18% of the collapses are due to shaking. The projected cost of an M=7.3 earthquake beneath Tokyo are $1.0 trillion (USD), which is 130% of the Japanese annual budget (Central Disaster Management Council 2005). Only about 5% of this loss is thought to be insured, and so the cost would be borne principally by home and business owners and the government. The total comprised $587 million direct losses associated with recovery and rebuilding, and $395 million in indirect losses due to production declines within and outside of Tokyo.
Our 29% probability of an M∼7.3 Tokyo earthquake in 30 years corresponds to an annual probability of 1.2%. Thus, the annual probable loss for Tokyo is $12 billion. Thus, in order to pay for the future earthquake, the Japanese government would need to save this amount annually, investing a portion to mitigate against future losses; but irrespective of Japanese actions, the consequences of a Tokyo earthquake of this magnitude are unlikely to be restricted to Japan. Japan is the largest owner of US Treasury securities, holding $700 billion or 17% of the total. How global capital markets would respond to a sudden withdrawal of these and other funds is unknown.
Lots of interesting graphics. Shaking at ground level depends not only on magnitude and shallowness of the quake, but also depends on how the waves reflect and refract, how the waves interfere, and the depth of soil (deep soil, typically near rivers, shakes like jelly; solid rock shakes much less).
http://rsta.royalsocietypublishing.o...1845/1965.full
Human, structural and financial consequences of a large Tokyo earthquake
The Cabinet Office of the Japanese government recently issued a risk assessment for large Tokyo earthquakes (Central Disaster Management Council 2005). They considered an M=7.3 earthquake beneath Tokyo, similar to the 1855 Ansei-Edo shock. The 240 000–840 000 destroyed buildings in their estimate depend strongly on wind speed and time of day, because high winds spread fire and rush hour exposes people to falling objects. If an M=7.3 earthquake struck at 18.00 in 15 m s−1 (33 miles h−1) winds, the Cabinet Office estimates 11 000 deaths, 210 000 wounded and 96 million tons of wreckage. About 57% of the deaths and 77% of the housing collapses are attributable to fire, and 28% of deaths and 18% of the collapses are due to shaking. The projected cost of an M=7.3 earthquake beneath Tokyo are $1.0 trillion (USD), which is 130% of the Japanese annual budget (Central Disaster Management Council 2005). Only about 5% of this loss is thought to be insured, and so the cost would be borne principally by home and business owners and the government. The total comprised $587 million direct losses associated with recovery and rebuilding, and $395 million in indirect losses due to production declines within and outside of Tokyo.
Our 29% probability of an M∼7.3 Tokyo earthquake in 30 years corresponds to an annual probability of 1.2%. Thus, the annual probable loss for Tokyo is $12 billion. Thus, in order to pay for the future earthquake, the Japanese government would need to save this amount annually, investing a portion to mitigate against future losses; but irrespective of Japanese actions, the consequences of a Tokyo earthquake of this magnitude are unlikely to be restricted to Japan. Japan is the largest owner of US Treasury securities, holding $700 billion or 17% of the total. How global capital markets would respond to a sudden withdrawal of these and other funds is unknown.