- Earthquakes
- Tsunamis
- Seismic Network
- About Us
Magnitude 2.7 - 148 miles S of Westdahl Peak
May 17, 2023 12:28:12 AKDT (May 17, 2023 20:28:12 UTC)
52.4946°N 163.4419°W Depth 6.5 miles (10 km)
This event has been reviewed by a seismologist
- 149 miles (241 km) SE of Akutan
- 154 miles (249 km) SE of Akutan Pass
- 156 miles (252 km) S of Fisher Caldera
- 157 miles (254 km) S of Isanotski Peaks
- 158 miles (256 km) S of Shishaldin Volcano
- 159 miles (257 km) S of Roundtop Mountain
- 159 miles (257 km) SE of Unalaska
- 160 miles (259 km) SE of Dutch
- 163 miles (264 km) S of False Pass
- 173 miles (280 km) SE of Makushin Volcano
- 180 miles (291 km) S of Frosty 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.