Perilous
Times
Japan earthquake 'increases likelihood of Tokyo disaster'
The likelihood of a massive earthquake directly beneath Tokyo has
significantly increased thanks to the March 11 disaster in
northern Japan.
By Julian Ryall in Tokyo
The Telegraph UK
7:00AM BST 30 Aug 2011
Scientists at the Tokyo Earthquake Research Institute said there
was evidence that pressures on the tectonic plates that meet below
the city have changed, raising the possibility of two or more
focal points on the plate boundaries shifting simultaneously. That
would result in an earthquake with a magnitude of 7.3, they
estimate.
And while that magnitude is smaller than the level-9 quake that
struck of the northeast coast of Japan nearly six months ago, the
impact on a densely populated and built-up area could be
catastrophic.
"We estimate that 10,000 people would die and the economic loss
would be around $1 trillion," Naoshi Hirata, a researcher at the
institute, told The Daily Telegraph.
That estimate may be on the conservative side, however, given that
around 18,000 people died in the March 11 earthquake and the
tsunami that it triggered.
"Even before March, we estimated that there was a 70 per cent
likelihood of a major earthquake affecting Tokyo at any time
within the next 30 years," said Hirata, who is also a member of
the government's Earthquake Research Committee.
"That is a very high probability and effectively means that there
will be a major disaster here, although we cannot at the moment
make a more accurate prediction of when it might strike," he said.
"All we can say is that individuals, companies, schools and the
national and local governments should be prepared," he said.
The scientists found that the March earthquake has had an affect
on all the plates that sit beneath the Japanese islands, one of
the most seismically active regions of the world, while there has
also been a steep increase in the number of earthquakes since
March, both those large enough to be felt by humans and those that
can only be detected by seismic instruments.
Residents of Tokyo would usually expect to feel one or two
earthquakes a month, but that has risen to an average of six a
month. Since March 11, there have been more than 500 tremors felt
across Japan.
The last major earthquake to strike Tokyo was in September 1923,
when the magnitude 7.9 Great Kanto Earthquake rattled eastern
Japan for 10 minutes and led to the deaths of as many as 140,000
people.