A strong earthquake struck off northern Japan on Friday, just days after a larger tremor injured at least 50 people in the region, Japan’s Meteorological Agency (JMA) announced.
The quake, upgraded to magnitude 6.7, prompted a tsunami advisory warning of waves up to one metre along the northern Pacific coast. Ultimately, tsunami waves reached about 20 centimetres in Hokkaido and Aomori before the advisory was lifted. Public broadcaster NHK reported no noticeable disruptions at the affected ports.
According to the U.S. Geological Survey, the quake’s epicenter was 130 kilometres off Kuji in Iwate Prefecture on Honshu. The shaking was weaker than Monday’s 7.5-magnitude quake, which damaged roads, shattered windows, triggered 70-centimetre tsunami waves, and knocked items from shelves.
Following that earlier quake, authorities ordered the evacuation of residents near a damaged 70-metre steel tower in Aomori due to fears it might collapse.
Japan’s Nuclear Regulation Authority confirmed there were no signs of abnormalities at nuclear facilities in the region.
After Monday’s tremor, the JMA issued a rare special advisory cautioning that another quake of equal or greater strength could occur within a week, covering the Sanriku coast on northeastern Honshu and Hokkaido facing the Pacific.
The region remains deeply affected by memories of the 2011 9.0-magnitude undersea earthquake and tsunami that killed about 18,500 people.
In August 2024, the JMA issued a similar advisory for Japan’s southern Pacific coastline warning of a potential “megaquake” along the Nankai Trough, an 800-kilometre undersea trench where tectonic plates converge. Government projections estimate a Nankai Trough quake and resulting tsunami could kill up to 298,000 people and cause $2 trillion in damage.
Japan, located on the Pacific “Ring of Fire,” sits atop four major tectonic plates and experiences about 1,500 earthquakes annually, most of them small, though their impact varies depending on depth and location.
