MONTH SEISMICITY REPORT FOR SEPTEMBER 2022
During the month of September 2022, the Alaska Earthquake Center reported 3603 earthquakes within the state. The largest earthquake was magnitude 5.1 that occurred on September 20 at 00:37:39 AKST (September 20, 08:37:39 UTC), 76 miles E of Chignik. It was an aftershock of July 28, 2021 M8.2 Chignik earthquake. Also there were two other M5.0 earthquakes: in Rat Islands on September 26th and in Icy Bay on September 29th.
Eleven earthquakes had magnitude of 4.0-4.9, four of which occurred in mainland Alaska. The most notable of them were a magnitude 4.8 on September 24th 36 miles NE of Valdez, and a magnitude 4.5 on September 18th in the Minto Seismic zone 45 miles W of Fairbanks, These earthquakes rattled interior, and many felt reports from Alaska communities were submitted.
We continue to monitor seismic activity within Anchorage, offshore Kodiak, Simeonof-Chignik aftershock zones as well as crustal seismic activity in Brooks Range, Seward Peninsula and Bering Strait. We also located about 90 ice quakes, 28 suspected quarry blasts, and 16 events as possible landslides. Ten earthquakes were reported as felt.
NOTABLE EVENTS IN DESCENDING ORDER OF MAGNITUDE
Magnitude 5.1, 67 miles SE of Yantarni Volcano, September 20 00:37:40 AKST
Magnitude 5.0, 27 miles W of Amchitka, September 26 03:39:19 AKST
Magnitude 5.0, 25 miles NE of Icy Bay, September 29 15:08:10 AKST
Magnitude 4.8, 43 miles S of Mt. Gareloi, September 7 12:41:04 AKST
Magnitude 4.8, 15 miles W of Pump Station #12, September 24 07:18:55 AKST
Magnitude 4.7, 24 miles S of Adak, September 1 18:45:31 AKST
Magnitude 4.7, 12 miles S of Attu, September 10 09:22:42 AKST
Magnitude 4.6, 32 miles NE of Semisopochnoi Island, September 15 06:02:39 AKST
Magnitude 4.6, 56 miles SE of Herbert Island, September 29 17:20:10 AKST
Magnitude 4.5, 65 miles S of Old Harbor, September 9 15:08:25 AKST
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.