In a terrifying scenario where four massive earthquakes strike in conjunction along the ocean trench from off the Tokai region to Shikoku, a 20-meter tsunami in Kochi Prefecture and a 15-meter tsunami in Shizuoka Prefecture could be unleashed, a computer simulation has found.
In a terrifying scenario where four massive earthquakes strike in conjunction along the ocean trench from off the Tokai region to Shikoku, a 20-meter tsunami in Kochi Prefecture and a 15-meter tsunami in Shizuoka Prefecture could be unleashed, a computer simulation has found.
Takashi Furumura, a professor at the Earthquake Research Institute at the University of Tokyo, also said that such combined earthquakes would trigger a tsunami as high as 4 meters in a part of Tokyo Bay.
The professor presented his study at the Seismological Society of Japan meeting on Oct. 14 in Shizuoka.
Furumura simulated an earthquake combined with two powerful temblors--the Hoei earthquake of 1707 and the 1605 Keicho earthquake.
The Hoei quake saw simultaneous Tokai, Tonankai and Nankai temblors, while the Keicho quake occurred along the shallow part of the Nankai Trough.
Strong ocean-trench temblors have repeatedly occurred along the trough.
Furukawa’s simulation estimated that the earthquake would be at the magnitude-8.8 level and could trigger tsunami 1.5 to 2 times higher than that of the Hoei earthquake.
In Tosa Bay in Kochi Prefecture, where the government estimates that a 10-meter tsunami at maximum is possible, a 20-meter tsunami would strike, the simulation found.
In Suruga Bay, a 10-meter tsunami would occur, compared with the government estimate of 6 meters at the maximum.
Furukawa predicts that a 17-meter tsunami would strike part of the Tokai region, while a 15-meter tsunami would engulf part of the Kii Peninsula.
Those compare to the tsunami estimated of at least 9.3 meters in height that struck Soma, Fukushima Prefecture, from the March 11 Great East Japan Earthquake, according to the Japan Meteorological Agency.
Furumura also simulated huge earthquakes in which ruptures of four temblors occur in conjunction in short intervals.
The largest tsunami to be spawned by the quakes could top 15 meters in Suruga Bay, 3-4 meters at the mouth of Tokyo Bay and more than 2 meters at the closed-off section of Tokyo Bay, the researcher predicted.