MONTH SEISMICITY REPORT FOR APRIL 2024

During the month of April 2024, the Alaska Earthquake Center reported 3467 earthquakes within the state with magnitudes ranging between 0.53-4.9 and depth between 0-179 km. The largest earthquake was magnitude 4.9 that occurred on April 9 at 17:55:13 AKDT, 54 miles S of Unalaska. There were twelve other events with magnitude larger than 4.0. All these earthquakes occurred along the subduction zone except the M4.2 earthquake 39 miles SE of Deering in Seward Peninsula.

We also reported seismic sources other than regional tectonic earthquakes. Of these, 39 were suspected quarry blasts (M0.6-2.1) in the vicinity of either Fort Knox, Usibelli or Manh Shah mines and 122 ice quakes (M0.8-1.9) primarily located in the Prince William Sound,  Glacier Bay  and Yakutat Bay.. Seismic activity remained recorded at the volcanoes of Alaska and Aleutian Islands with a total of 47 events (M0.9-1.3). There was also a M1.25 landslide recorded at Bering Glacier.

Nine events were reported as felt in April.

NOTABLE EVENTS IN DESCENDING ORDER OF MAGNITUDE


Magnitude 4.9, 54 miles S of Unalaska, April 9 17:55:14 AKDT
Magnitude 4.9, 36 miles E of Amchitka, April 26 20:42:59 AKDT
Magnitude 4.8, 88 miles SE of Westdahl Peak, April 10 00:28:52 AKDT
Magnitude 4.6, 52 miles SE of Amukta Pass, April 10 15:41:09 AKDT
Magnitude 4.6, 2 miles S of Attu, April 15 10:17:02 AKDT
Magnitude 4.6, 98 miles SE of Chignik, April 18 23:27:33 AKDT
Magnitude 4.6, 47 miles SE of Amchitka, April 24 13:26:05 AKDT
Magnitude 4.4, 33 miles E of Okmok Caldera, April 4 11:57:04 AKDT
Magnitude 4.2, 17 miles SE of Talkeetna, April 13 12:10:45 AKDT
Magnitude 4.2, 37 miles SE of Yunaska Island, April 16 17:48:25 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.