While there has been no earthquake today and no tsunami threat exists at this moment, a Japanese government panel says tsunami waves measuring more than 60 feet high could hit northern Japan if a megaquake of magnitude 9 or stronger occurs in one of two deep-sea trenches located east of the country.
A study, which launched after the 2011 tsunami disaster, explored how significant potential earthquakes could be in either the Chishima Trench or Japan Trench, and how significant tsunami waves from such a quake could be. The targeted area of the Chishima Trench extends from the Kuril Islands to Hokkaido while the area of the Japan Trench extends from Hokkaido to Iwate Prefecture.
According to the report released today, the panel’s estimate says a quake along the Chishima Trench could have a magnitude of 9.3. Based on such an off-shore earthquake, parts of eastern Hokkaido would be hit by tremors with an intensity of six-plus to seven on the Japanese scale of zero to seven. With such an earthquake, a wide area of eastern Hokkaido would see tsunami more than 60 feet high; waves nearly 90 feet high could reach the town of Erimo.
The same report suggests it’s possible that a quake along the Japan Trench could have a magnitude of up to 9.1. If such a quake were to strike, parts of Aomori and Iwate prefectures could have tremors with an intensity of six-plus. In this scenario, tsunami waves would top 30 feet in northeastern Japan. Hachinohe City in Aomori Prefectures would be hit by tsunami as high as 78 feet while Miyako City in Iwate Prefecture could see waves up to 100 feet. Based on this analysis, some areas could be hit by waves higher than those that struck in 2011.
The Cabinet Office plans to estimate the extent of damage and draw up disaster control measures based on these new figures by the end of March next year.