MONTH SEISMICITY REPORT FOR APRIL 2023
During the month of April 2023, the Alaska Earthquake Center reported 3963 earthquakes within the state with magnitudes ranging between 0.3 and 5.1 and the depth between 0-242 km. The largest earthquake was magnitude 5.1 that occurred on April 8 at 12:25:11 AKDT (April 8, 20:25:11 UTC), 28 miles SE of Akutan. There were 6 other earthquakes with magnitudes 4.1-4.8.
The most notable event of the month was a M4.8 on April 9th, 2023 at 4:16PM AKDT (April 10th, at 00:16 UTC) 12 miles SE of Tyonek in the Cook Inlet. It was widely felt in Kenai and Anchorage area. The largest number of 'Did You Feel It' reports, 972, came from this earthquake.
We also reported 234 seismic events associated with volcanic activity at several volcanoes such as the Katmai volcanic group, Aniakchak, Makushin, and Tanaga-Takawangha. The seismic activity at volcanoes in April was much lower than it was in March. The reported events also included 72 ice quakes primarily located in the Prince William Sound, Icy Bay and Yakutat Bay Areas as well as 41 suspected quarry blasts in the vicinity of either Fort Knox or Usibelli mines.
Seven earthquakes were reported as felt in April.
NOTABLE EVENTS IN DESCENDING ORDER OF MAGNITUDE
Magnitude 5.1, 28 miles SE of Akutan, April 8 12:25:11 AKDT
Magnitude 4.8, 28 miles S of Atka Pass, April 7 23:17:41 AKDT
Magnitude 4.8, 12 miles SE of Tyonek, April 9 16:16:56 AKDT
Magnitude 4.8, 102 miles SE of Perryville, April 24 05:09:11 AKDT
Magnitude 4.7, 6 miles W of Kasatochi Island, April 21 10:17:12 AKDT
Magnitude 4.6, 95 miles S of Mt. Sergief, April 22 04:54:54 AKDT
Magnitude 4.1, 24 miles W of Amchitka, April 24 08:51:43 AKDT
Magnitude 3.9, 47 miles S of Mt. Gareloi, April 6 11:36:35 AKDT
Magnitude 3.9, 80 miles SE of Chignik, April 22 13:23:57 AKDT
Magnitude 3.9, 14 miles NW of Anchorage, April 3 04:27:15 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.