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Magnitude 3.0 - 91 miles S of Amchitka
March 15, 2023 23:23:20 AKDT (March 16, 2023 07:23:20 UTC)
50.2117°N 178.8007°E Depth 16.3 miles (26 km)
This event has been reviewed by a seismologist
- 122 miles (197 km) S of Davidof Island
- 122 miles (197 km) S of Little Sitkin Pass
- 125 miles (202 km) S of Semisopochnoi Island
- 128 miles (207 km) S of Segula Peak
- 141 miles (228 km) SE of Kiska Volcano
- 151 miles (244 km) SW of Mt. Gareloi
- 176 miles (285 km) SW of Tanaga Volcano
- 193 miles (312 km) SE of Buldir Is
- 193 miles (312 km) SE of Buldir Island
- 201 miles (325 km) SW of Bobrof Island
- 211 miles (342 km) SW 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.