A 7.7-magnitude earthquake off the coast of Japan triggered a tsunami warning
An earthquake measuring 7.7 on the Richter scale struck off the north-eastern coast of Japan on Monday. The authorities have urged residents to stay away from coastal areas due to the threat of tsunami waves up to three metres high, Reuters reports.
The tremors were recorded at 16:53 local time. Approximately two hours after the earthquake, tsunami waves up to 80 centimetres high were recorded. The tsunami warning was subsequently downgraded to an advisory.
Japanese government spokesman Minoru Kihara told a press conference that, as of the evening, there had been no reports of fatalities or significant damage in Tokyo.
In several port cities, including Otsuchi and Kamaisi, the evacuation of thousands of residents had previously been ordered. These towns were affected by the massive earthquake and tsunami in 2011.
Due to the tremors, high-speed train services were suspended and sections of motorways were closed.
Following the earthquake, the government warned of an increased risk of a stronger tremor. According to a government official, the probability of an earthquake measuring 8 or higher along the Japan and Kuril Trench within a week is usually around 0.1%, but following the current earthquake, it could rise to approximately 1%.
The official urged citizens to take safety precautions and be prepared to protect their own lives.
The tremors were rated at ‘upper 5’ on the Japanese intensity scale, making movement difficult and potentially causing the collapse of unreinforced concrete walls. The epicentre of the earthquake was in the Pacific Ocean at a depth of 20 kilometres, the Japan Meteorological Agency reported.
According to the agency’s estimates, a three-metre-high tsunami wave could cause flooding in low-lying areas and poses a danger to people within its path.
Japan is situated within the so-called Ring of Fire and is one of the world’s most seismically active countries. Earthquakes occur in the country at least every five minutes. Japan accounts for around 20% of the world’s earthquakes with a magnitude of 6 or higher.
There are currently no operational nuclear power stations in the affected areas. Hokkaido Electric Power Co and Tohoku Electric Power Co have reported that no abnormalities have been detected in the operation of their shut-down facilities.
