Magnitude 3.3 - 88 miles S of Nikolski
September 9, 2019 21:15:32 AKDT (September 10, 2019 05:15:32 UTC)
51.6909°N 168.4616°W Depth 19.5 miles (31 km)
This event has been reviewed by a seismologist
- 99 miles (160 km) S of Mt. Vsevidof
- 100 miles (162 km) SE of Mt. Cleveland
- 101 miles (163 km) S of Mt. Recheshnoi
- 102 miles (165 km) SE of Herbert Island
- 104 miles (168 km) SE of Kagamil Island
- 107 miles (173 km) SE of Carlisle Island
- 110 miles (178 km) SE of Uliaga Island
- 115 miles (186 km) SE of Yunaska Island
- 121 miles (196 km) S of Okmok Caldera
- 129 miles (209 km) SE of Chagulak Island
- 156 miles (252 km) S of Bogoslof Island
- 172 miles (278 km) SW of Dutch
- Magnitude type: Ml2
- Event type: earthquake
Tectonic Setting of the Aleutian Islands
The Aleutian Arc marks the region where the Pacific Plate subducts into the mantle beneath the North American Plate. It is a seismically active region, evidenced by the thousands of earthquakes occurring each year. Since 1900, this region has hosted several major megathrust earthquakes, including the 1957 M8.6 in the Andreanof Islands, the 1965 M8.7 in the Rat Islands, the 1986 M7.9 and the 1996 M7.9 in the Andreanof Islands, and the 2003 M7.8 in the Rat Islands. Together they have ruptured the entire length of the megathrust boundary in this region. Another notable source of seismicity in the arc is the zone 6-9 miles (10-15 km) wide of intermediate-depth earthquakes within the subducting Pacific Plate, known as the Wadati-Benioff Zone. The largest recorded intermediate-depth earthquake in this region was the 2014 M7.9 Little Sitkin event. A third source of seismicity in this region are shallow earthquakes associated with volcanic processes and crustal faults within the overriding North American Plate. They occur regularly and may produce vigorous aftershock or swarm-like sequences.