Magnitude 6.7 - 15 miles SE of Mt. Cleveland

July 17, 2010 21:56:43 AKDT (July 18, 2010 05:56:43 UTC)
52.6873°N 169.6616°W Depth 2.6 miles (4 km)

20 miles (32 km) E of Herbert Island
21 miles (34 km) S of Kagamil Island
22 miles (35 km) SE of Carlisle Island
27 miles (43 km) S of Uliaga Island
37 miles (59 km) SW of Nikolski
44 miles (71 km) E of Yunaska Island
51 miles (82 km) SW of Mt. Vsevidof
57 miles (92 km) SW of Mt. Recheshnoi
63 miles (102 km) E of Chagulak Island
81 miles (131 km) SW of Okmok Caldera
100 miles (162 km) E of Amukta Pass
154 miles (249 km) SW of Dutch

Magnitude type: M_w²
Event type: N/A

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.