Up to 23,000 people in Tokyo and surrounding areas would die if a magnitude 7.0 earthquake were to strike directly beneath the 23 wards of the capital, a government panel said Thursday.
The projection, made by the Central Disaster Management Council, covers Tokyo and Saitama, Chiba and Kanagawa prefectures.
According to a government estimate, there is a 70 percent chance of a quake with a magnitude of around 7.0 occurring in the southern part of the Kanto region in and around Tokyo within a 30-year period.
Central Tokyo and many other areas would experience shaking of upper 6 or higher on the Japanese seismic intensity scale to 7. Economic damage from such a quake is forecast at ¥95 trillion.
The council also said that up to 70,000 people would be killed by a magnitude-8.0 earthquake with its center in the areas between Sagami Bay off Kanagawa and the Boso Peninsula in Chiba, similar to the Great Kanto Earthquake of 1923. The council showed the estimate as a reference.
In its previous estimate in 2004, the council projected a death toll of up to 12,000 in the case of a powerful quake directly under the Tokyo metropolitan area.
The scope of damage in the latest projection is far greater due to an estimated increase in deaths from such causes as fire, after the council studied all earthquakes possible in the metropolitan area following the 9.0-magnitude earthquake and tsunami in the Tohoku region on March 11, 2011.
To estimate damage details, the council mainly studied an earthquake directly hitting the crowded southern part of central Tokyo.
Damage would be at its worst if the quake struck at around 6 p.m. in winter during winds of 29 kph. The shaking would lead to the destruction of 175,000 buildings, while fires would destroy 412,000 buildings.
With dry winter air, the strong winds and the fact that many people would be cooking dinner at the time would exacerbate the disaster, according to the council.
Collapsing buildings would kill 6,400 people, while 16,000 people would die in fires. Some 123,000 people would suffer injuries, it projected.