Magnitude 1.9 - 8 miles NE of Mt. Sergief

May 13, 2022 00:57:06 AKDT (May 13, 2022 08:57:06 UTC)
52.1517°N 174.8395°W Depth 3.0 miles (4 km)

This event has been reviewed by a seismologist

13 miles (21 km) E of Koniuji Island
25 miles (40 km) NE of Atka Pass
27 miles (43 km) W of Atka
29 miles (47 km) E of Kasatochi Island
55 miles (89 km) E of Great Sitkin Island
75 miles (121 km) E of Mt. Adagdak
80 miles (129 km) E of Adak
82 miles (132 km) E of Mt. Moffett
100 miles (162 km) E of Kanaga Volcano
101 miles (163 km) W of Seguam Island
112 miles (181 km) E of Bobrof Island

Magnitude type: M_l²
Event type: earthquake

Tectonic Setting of the Aleutian Islands

The world's largest earthquakes originate along convergent plate boundaries such as the Aleutian megathrust. Starting in 1938, a series of three great earthquakes ruptured the subduction zone along its entire length from the Alaska Peninsula to the western Aleutians with the exception of a small gap near the Shumagin Islands. The sequence began with a M8.2 earthquake southwest of Kodiak Island. A M8.6 in the Andreanof Islands followed in 1957, and the sequence concluded with the Rat Islands M8.7 in 1965. The Shumagin Gap still has not ruptured, but GPS observations suggest that little strain has built up in this region.

Another notable source of seismicity in the arc are the intermediate depth earthquakes within the subducting Pacific Plate, known as the Wadati-Benioff zone. The largest recorded earthquake of this kind was the 2014 M7.9 Little Sitkin event. Shallow earthquakes associated with volcano processes and crustal faults within the overriding North American plate occur regularly and may produce vigorous aftershock or swarm-like sequences.