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Magnitude 2.4 - 111 miles SE of Atka
May 22, 2023 16:22:56 AKDT (May 23, 2023 00:22:56 UTC)
50.7199°N 173.1927°W Depth 1.4 miles (2 km)
This event has been reviewed by a seismologist
- 115 miles (186 km) S of Seguam Island
- 119 miles (192 km) SE of Mt. Sergief
- 124 miles (201 km) SW of Amukta Pass
- 130 miles (210 km) SW of Amukta Pass
- 130 miles (210 km) SE of Atka Pass
- 133 miles (215 km) SE of Koniuji Island
- 142 miles (230 km) SE of Kasatochi Island
- 155 miles (251 km) SW of Chagulak Island
- 156 miles (252 km) SE of Great Sitkin Island
- 169 miles (274 km) SE of Adak
- 170 miles (275 km) SW of Yunaska Island
- Magnitude type: Ml2
- 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.