Japan earthquake warning: Japan's Meteorological Agency issues first-ever 'Megaquake' warning after powerful 7.1 magnitude tremor
The Japan Meteorological Agency has issued its first-ever ‘Megaquake’ warning.
This means there is a risk of a huge earthquake along the Pacific coast. Japan’s prime minister, Fumio Kishida, has cancelled a visit to central Asia this weekend after experts warned that the risk of a “megaquake” occurring had increased following the 7.1 magnitude earthquake that struck in the south-west on Thursday (8 August).
The quake on the southernmost main island of Kyushu triggered a tsunami warning. No deaths or major damage have been reported.
The agency’s warning that the risk of a huge earthquake occurring along the Nankai Trough was higher than usual does not mean that a quake will definitely occur in the coming days. Public broadcaster NHK said Kishida’s overseas trip had been cancelled so that he could prepare for any outcome.
The meteorological agency’s megaquake advisory warned that “if a major earthquake were to occur in the future, strong shaking and large tsunamis would be generated”. It added: “The likelihood of a new major earthquake is higher than normal, but this is not an indication that a major earthquake will definitely occur during a specific period of time.”
The advisory concerns the Nankai Trough “subduction zone” between two tectonic plates in the Pacific Ocean, where massive earthquakes have hit in the past. The 800-kilometre (500-mile) undersea trough runs from Shizuoka, west of Tokyo, to the southern tip of Kyushu and has been the site of destructive earthquakes of magnitude 8 or 9 every 100 to 200 years.
These so-called “megathrust quakes” have unleashed dangerous tsunamis along the southern coast of Japan. Although it is impossible to predict the precise timing of earthquakes, government experts believe there is a 70% to 80% chance of an megaquake measuring magnitude 8 or 9 happening around the trough in the next 30 years. In the worst-case scenario, the disaster would kill 300,000 people, with some experts estimating a financial hit as high as $13tn.