A powerful earthquake struck off the coast of Fukushima, Japan early on Tuesday, triggering tsunamis and nuclear power plant interruption in the area.
The earthquake was recorded at a depth of 30km, about 37km off the coastline near Fukushima, the site of the devastating 2011 quake.
Warnings of a 3m tsunami was issued for Fukushima and the Miyagi to the north, before later being downgraded to advisory. Smaller tsunami warnings were also issued by the Japan Meteorological Agency for higher up Japan’s north-east coast and on the south-east coast.
The earthquake had a preliminary magnitude of 7.3 but was later downgraded to 6.9 by the US Geological Survey.
The Japanese quake came as a tremor with a preliminary magnitude of 6.3 struck central New Zealand, little more than a week after a powerful tremor centred in the upper South Island rocked the country and killed two people.
The Japan Meteorological Agency said Tuesday’s tremor was an aftershock of the magnitude 9.0 earthquake that spawned a deadly tsunami in the same region in 2011.
The agency said that another large quake could be expected within the next few days, and people in the region were advised to “remain cautious” for the next week.
Tsunamis hit at various points on the Fukushima coastline. They ranged from 30cm to 1.4m high. One at Onahama Port was 60cm high, another at Soma was 90cm high, while Sendai prefecture recorded a 1.4m tsunami.
An almost 1m high tsunami struck the Fukushima Daini nuclear facility.
There have been no reports of serious injuries or fatalities.
Japan’s national public broadcaster, NHK, reported a nuclear rod “cooling pond” at Fukushima’s Daini reactor had stopped, but power company Tepco has switched the cooling system back on.
This incident was not expected to cause danger as no nuclear rod cooling water had leaked.
— 映像職人 JERONI毛 郷古哲哉 (@jerotter) November 22, 2016
Fukushima Daini is the sister plant to Daiichi which had three catastrophic reactor failures during the February 2011 Japan earthquake and tsunami, triggering a public health disaster.
NHK urged residents to “remember” the 2011 earthquake and tsunami disaster and to “evacuate now”.
Its broadcast showed sea currents moving at Fukushima with evacuation sirens blaring in the background.
Footage posted to social media from north of Japan’s capital Tokyo showed the earthquake hitting a train station:
— dotemirates (@dotemirateseng) November 21, 2016
Japan’s chief cabinet secretary Yoshihide Suga gave a press conference warning those in the areas to evacuate immediately.
Infrastructure checks were still occurring at other nuclear power facilities in the warning zones.
Fukushima was devastated during the 2011 Japan earthquake and tsunami. While there has still been no confirmed death toll, around 22,000 people are believed to have died as a result of the initial earthquake and tsunami and by post-disaster health conditions.
That ensuing 15.7m tsunami destroyed the nuclear reactor at the Fukushima Power plant, causing the largest nuclear disaster since Chernobyl, in the then Soviet Union, in 1986.
Ring of fire
Tuesday’s New Zealand earthquake was centred off the coast of the North Island, 138km from Palmerston North, at a depth of 37km.
The New Zealand Herald reported the quake as a 5.4 magnitude shake, centred in the Hawkes Bay region on the east coast of the North Island.
Both the Japanese and NZ earthquakes took place in the notorious “Ring of Fire” basin in the Pacific Ocean, home to frequent tremors and volcanic eruptions.
Comprising a 40,000 km horseshoe shape area ringing the Pacific Ocean, the Ring of Fire is home to around 90 per cent of the world’s earthquakes.
The area is also associated with an estimated 75 per cent of the world’s active and dormant volcanoes.
One of the ring’s edges is perilously close to Japan’s eastern coastline and where Tuesday’s earthquake hit.