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Magnitude 1.9 - 18 miles W of Mt. Gareloi
May 15, 2023 09:48:47 AKDT (May 15, 2023 17:48:47 UTC)
51.7916°N 179.2139°W Depth 6.9 miles (11 km)
This event has been reviewed by a seismologist
- 46 miles (74 km) W of Tanaga Volcano
- 52 miles (84 km) E of Semisopochnoi Island
- 76 miles (123 km) W of Bobrof Island
- 79 miles (128 km) E of Amchitka
- 88 miles (142 km) W of Kanaga Volcano
- 103 miles (167 km) E of Little Sitkin Pass
- 105 miles (170 km) E of Davidof Island
- 106 miles (171 km) W of Mt. Moffett
- 109 miles (176 km) W of Adak
- 113 miles (183 km) W of Mt. Adagdak
- 114 miles (184 km) E of Segula Peak
- 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.