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Magnitude 2.3 - 10 miles SW of Amchitka
May 22, 2023 11:26:24 AKDT (May 22, 2023 19:26:24 UTC)
51.4122°N 178.8724°E Depth 26.2 miles (42 km)
This event has been reviewed by a seismologist
- 43 miles (69 km) SE of Little Sitkin Pass
- 44 miles (71 km) SE of Davidof Island
- 49 miles (79 km) SW of Semisopochnoi Island
- 52 miles (84 km) SE of Segula Peak
- 73 miles (118 km) SE of Kiska Volcano
- 104 miles (168 km) W of Mt. Gareloi
- 132 miles (214 km) W of Tanaga Volcano
- 141 miles (228 km) SE of Buldir Is
- 142 miles (230 km) SE of Buldir Island
- 161 miles (261 km) W of Bobrof Island
- 174 miles (282 km) W of Kanaga Volcano
- 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.