Just five years ago Japan's "worst case" quake scenario was an 8.6 quake every 500 years!

http://www.physorg.com/news10267.html


Japan panel posits worst case earthquake


January 26, 2006


An earthquake off the northeastern coast of Japan could kill up to 2,700 people and trigger a 72-foot tsunami, a Japanese government panel has predicted.



The government's Central Disaster Management Council focused on the Japan and Chishima trenches in the Pacific Ocean and created eight scenarios involving different locations, seasons, times of day and wind speeds, the Asahi Shimbun reported Thursday.

The worst case, in terms of casualties, would be if the Pacific Plate pulled down the North American Plate, causing a temblor with a magnitude of 8.6 off the coast of Iwate prefecture in northeastern Japan at 5 a.m. on a winter's day.

It would not cause extensive land shaking, but could trigger a tsunami that reached the Pacific coast of Japan in about 30 minutes. The panel predicted waves of up to 22 meters, or more than 72 feet, by the time they reached shore.

The maximum overall death toll would be 2,700.

The number of casualties would be greater in the winter because the temblor could cause avalanches and more accidents on icy roads.

A magnitude 8.6 earthquake is predicted to occur in the area every 500 years.