During the month of October 2023, the Alaska Earthquake Center reported 3633 earthquakes within the state with magnitude ranging between 0.8 and 6.4 and depth between 0 and 238 km.  The largest earthquake was magnitude 6.4 that occurred on October 16 at 03:35:31 AKST (October 16, 11:35:31 UTC), 3 miles W of Adak in Andreanof Islands.

Two moderate sized earthquakes of magnitude 5.1 and 5.3 occurred near Glacier Bay in Southeast Alaska within a 45 minutes period  on the evening of October 27. They were followed by about one hundred aftershocks within the next three days. These two earthquakes were felt in Southeast Alaska communities and in Northern British Columbia, Canada. More information on these events is available here:

 We also reported  30 suspected quarry blasts (magnitude 0.9-2.2), all of which were located in the vicinity of either Fort Knox or Usibelli mines in the interior of Alaska; 220 ice quakes ( magnitude 0.8-2.9), primarily located in the Prince William Sound, Icy Bay, Yakutat Bay areas as well as at Wright Glacier; and 90 seismic events associated with volcanic activity (M0.8-2.7).

25 earthquakes were reported as being felt in October 2023.


Magnitude 6.4, 3 miles S of Mt. Moffett, October 16 03:35:31 AKDT
Magnitude 5.6, 9 miles S of Chagulak Island, October 11 18:41:14 AKDT
Magnitude 5.3, 36 miles SW of Klukwan, October 27 19:44:11 AKDT
Magnitude 5.1, 33 miles SW of Klukwan, October 27 19:01:49 AKDT
Magnitude 4.4, 41 miles S of Nikolski, October 6 03:34:04 AKDT
Magnitude 4.3, 54 miles S of Unalaska, October 2 02:04:43 AKDT
Magnitude 4.3, 103 miles W of Elfin Cove, October 10 00:32:46 AKDT
Magnitude 4.3, 46 miles SE of Mt. Cleveland, October 20 11:39:40 AKDT
Magnitude 4.3, 33 miles W of St. George, October 30 16:10:02 AKDT
Magnitude 4.2, 3 miles N of Anchorage, October 6 06:01:19 AKDT

This report was compiled by N. Kozyreva

The data in this report are preliminary and subject to revision. The earthquake parameters have been determined by the AEC, with supplemental data provided by the USGS National Earthquake Information Center. The data are released on the condition that none of the cooperating agencies may be held liable for any damaged resulting from its authorized or unauthorized use.

For more information on earthquakes and seismology, contact the AEC at 907-474-7320.