Nankai Trough quake predicted to cause 1,800 fatalities on Izu and Ogasawara islands


The Tokyo metropolitan government has published more findings from a panel of earthquake experts commissioned to predict the number of casualties likely to result from a Nankai Trough earthquake.

According to the estimates, about 1,800 deaths are predicted on casualties are expected on the Izu and Ogasawara island chains off Tokyo in the event of a quake and tsunami, the Disaster Prevention Council panel said in its findings, according to Sankei Shimbun.

However, the panel added that the number of casualties would be reduced if people in affected areas are able to quickly reach refuge spots.

However, due the distances involved, waves reaching Tokyo itself are expected to be a maximum of 2.5 meters tall. The panel predicted that although the earthquake may be felt in the capital, the shaking is expected to be the equivalent of 5 or below on the Japan Meteorological Agency seismic intensity scale.

In August of last year, the government tasked two panels of experts with drawing up a realistic assessment of what Japan could expect in the event of a Nankai Trough earthquake.

The panels concluded that an offshore Pacific earthquake like the one that hit Japan in 2011 could a trigger 34-meter tsunami, resulting in at least 323,000 deaths, 220 trillion yen in economic losses and the devastation of much of the coastline between Honshu and Kyushu.

The panel's estimate of fatalities following a Nankai Trough earthquake was 13 times higher than that offered by the central government in 2003. The discrepancy is thought to be partly due to the fact that 2011's Tohoku Earthquake was magnitude 9.0. The power of the earthquake reportedly surprised experts, who had wrongly assumed that no quake greater than magnitude 8.0 would occur in the region off Miyagi Prefecture in northern Japan.

A key concern is the 60 industrial and petrochemical complexes along the coast that could leak chemicals and other toxins into the environment. The report did not outline potential costs from any nuclear accidents that might arise due to such a disaster.

It said Japan's GDP would drop by over 9% in the year following such a disaster. The economy contracted 0.6% in 2011 but has failed to regain strong growth despite heavy government spending on rebuilding.

The disaster panel recommended that companies with operations in the regions likely to be worst hit by a Nankai earthquake and tsunami accelerate plans to shift factories further inland or to higher ground.

The panel's findings may build support for extra government spending on disaster preparedness and retrofitting buildings and other structures to make them more quake resistant. The Cabinet Office's report said the 169.5 trillion yen in damage to property and infrastructure could be more than halved if such measures are completed.

© Japan Today/AP

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I noticed this in the Japanese vernacular press and wondered about the reassuring title. Only 1,800 fatalities estimated? But it is worth reading the article right through. These figures are only for a string of small off-shore islands...

In the middle of the article is the real story and much closer to what I thought we all roughly knew. A Nankai Trough earthquake would cause 320,000 deaths, 13 times higher than the 2003 estimate.

Quote: "...could trigger a 34-meter tsunami, resulting in at least 323,000 deaths, 220 trillion yen in economic losses and the devastation of much of the coastline between Honshu and Kyushu."

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This article from the Sankei Shinbun in Dec 2012 says the seawall at Hamaoka Nuclear Power Plant will be extended with a steel fence to an overall height of 22 meters to deal with a maximum possible tsunami of 19 meters. Let's hope everyone has their math(s) correct.

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Dear god, 323,000 deaths and 220 trillion yen in damages? If that came to pass, Japan would surely never recover again..

Looking up on the Nankai trough however, there was supposedly a 40%~ chance of a major rupture at the far Northeastern segment of the trough during 2000-2010, and it is apparently inevitable that there will be a major earthquake on that trough..

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Whether its another one up north, or one in Nankai, or one in Tokai, doesn't really make a difference. There will, eventually, sooner or later be another massive quake in Japan. Thats life.

All we can do is be prepared as possible as individuals - don't expect much immediate help from the government if there really are 323000 deaths and such a huge amount of damage. Stories like these don't really do anything to help, in my opinion, except that they MIGHT encourage a few people to go and get an earthquake kit together.

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There's a difference between "would" and "could".

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albaleo, point taken! :8)

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That's if it's a 9.

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There's no way they can predict what will happen and on what magnitude . It all depends on the ripple effect ,how many and direction of them. Once again the "experts" will be caught with their pants down. If you look at the population and the number of deaths last time it happened there and multiply the population (saying buildings are safer is misleading) plus all the tinder box houses built within inches of each other . They are shooting low. Just take a look at the congested power line services when you walk down the street...think about the gas lines underneath ...reflect back on Osaka and Kobe ...Tokyo and Kanagawa will look like a few N bombs dropped here.

They'll blame the panel of experts and all insurance companies will go bankrupt or burn up in flames ( records included )

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This is coming... and much sooner than any of us think...

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If it happens, it happens. Buildings may not withstand the quake. Be prepared to get to higher ground quickly. Be prepared to provide for yourself because government will not help.

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It has happened in the past and will happen in the future. Could it be in a week or a century.

And what? Any prospective urbanist changes, move of the factories to safest places, de-centralization of the government...?

What the hell are they waiting for? Total destruction of Japan?

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Could it be in a week or a century.

I have a strong feeling it will be this year or next... just get ready for it.

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Hmm, well you seem to be a reliable enough source

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AGAIN!!..It seems somehow a good excuse to boosting people into spending more money...good for Abe san and the economy!! In my country (Italy) quakes (unfortunately) are seen as business opportunities cause obviously after destruction there is construction so why bothering to put in place all the anti seismic measures and techniques!!

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And here I was thinking about moving to Izu with the family...

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choiwaru, what are you basing that on?

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