A swarm of earthquakes and aftershocks shook Alaska's western Aleutian Islands on Sunday.
Scientists at the Alaska Earthquake Center are monitoring an unusually high number of moderate earthquakes near Adak Island. About a dozen tremors between magnitude 6.3 and 5 struck within hours on Sunday.
Residents describe the shaking as "light" and "weak" but remain alert, checking emergency supplies and tracking the ongoing activity.
Scientists say large earthquakes are common in the Aleutians, where the Pacific plate moves beneath the North American plate. While this swarm hasn't raised alarms, its location near historic quake sites has drawn attention. They expect aftershocks in the region, particularly magnitude 5 and smaller, to continue for days or weeks. The earthquake center reports about 100 aftershocks near Adak as of Monday morning, which they say is typical following magnitude 6 earthquakes.
A magnitude 5 earthquake struck further to the east closer to King Cove and False Pass on Monday morning. Scientists say that quake likely wasn't triggered by the earthquakes near Adak due to the distance between the locations.
The earthquake swarm follows a magnitude 7 earthquake off California's coast last week. Scientists at the United States Geological Survey say the events aren't connected - California and the Aleutians involve different tectonic plates and fault systems.