The 6.4-magnitude tremor occurred at 8:12 a.m. Hawaii time at a depth of 18 miles.
Its epicenter was in an 810-mile volcanic archipelago located between Japan and Russia which separates the Sea of Okhotsk from the North Pacific Ocean.
The USGS describes the area as among the most seismically active in the world. The islands mark the location of the Kuril-Kamchatka tectonic arc, a subduction zone interface between the overriding North America plate and the Pacific plate.
The area has been the site of frequent earthquakes including seven since 1900 of 8.3 magnitude or greater.
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