Shallow M5.6 earthquake hits offshore Miyagi, Japan on August 26, 2026

A shallow M5.6 earthquake was recorded at 19:21 UTC on August 26, 2026, approximately 212 km (132 miles) east of Onagawa Chō, Japan. The hypocenter was located at a depth of 10.0 km (6.2 miles), according to the USGS.

The coordinates place the epicenter offshore, in the Pacific Ocean, east of Miyagi Prefecture in northeastern Japan. The nearest major municipality is Onagawa Chō, with the earthquake occurring well offshore from populated coastal areas.

Given the offshore location, nearby critical infrastructure may include shipping lanes, offshore energy platforms, and communications cables linking Japan to the broader Asia-Pacific region. The region is also traversed by busy maritime routes.

There is no tsunami threat associated with this earthquake, based on its location and available data.

USGS issued a green alert for this event, indicating a low likelihood of casualties or damage. The maximum estimated intensity for this event is III, and the significance index is 482 (on a scale that runs through 1 000), based on magnitude, felt reports, and estimated impact.

Japan is located along the Pacific “Ring of Fire,” where the Pacific Plate subducts beneath the Eurasian Plate, resulting in frequent and sometimes significant seismic activity. This area is known for its complex tectonics and history of major offshore earthquakes.

This information was last updated at 19:46 UTC on August 26, 2026.