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Magnitude 3.8 - 94 miles S of Amukta Pass
February 7, 2023 03:47:44 AKST (February 7, 2023 12:47:44 UTC)
51.0769°N 171.193°W Depth 12.4 miles (20 km)
This event has been reviewed by a seismologist
- 102 miles (165 km) S of Amukta Pass
- 102 miles (165 km) SE of Seguam Island
- 103 miles (167 km) S of Chagulak Island
- 109 miles (176 km) S of Yunaska Island
- 125 miles (202 km) S of Herbert Island
- 132 miles (214 km) SW of Mt. Cleveland
- 135 miles (218 km) S of Carlisle Island
- 147 miles (238 km) SW of Kagamil Island
- 150 miles (243 km) SE of Atka
- 150 miles (243 km) SW of Uliaga Island
- 162 miles (262 km) SW of Nikolski
- 276 miles (447 km) SW of Dutch
- 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.