There are no immediate reports of damage or injuries from the major temblor at 8:25 a.m. Friday, local time. It was followed by multiple aftershocks, including one measuring magnitude 4.5.
The Alaska Earthquake Information Center says the primary earthquake was centered 67 miles southwest of Adak, Alaska, and shaking lasted up to one minute.
The village is about 1,200 miles southwest of Anchorage.
The earthquake didn't trigger a tsunami warning, but Michael Burgy with the West Coast and Alaska Tsunami Warning Center in Palmer, Alaska, says the center is monitoring for potential tsunamis caused by landslides, either on land or under water.