Magnitude 1.2 - 89 miles W of Anaktuvuk Pass
September 15, 2020 10:11:07 AKDT (September 15, 2020 18:11:07 UTC)
68.2246°N 155.1867°W Depth 1.7 miles (2 km)
This event has been reviewed by a seismologist
- 101 miles (163 km) NE of Kobuk
- 105 miles (170 km) NE of Ambler
- 106 miles (171 km) NE of Shungnak
- 110 miles (178 km) SW of Umiat
- 130 miles (210 km) NW of Bettles
- 133 miles (215 km) NW of Allakaket
- 144 miles (233 km) NW of Wiseman
- 147 miles (238 km) NW of Coldfoot
- 149 miles (241 km) W of Pump Station #4
- 153 miles (248 km) N of Hughes
- 154 miles (249 km) NW of Pump Station #5
- Magnitude type: Ml2
- Event type: earthquake
Tectonic Setting of the Brooks Range
Seismicity in the Brooks Range is characterized by intraplate earthquakes associated with mountain building and crustal reorganization. A broad earthquake band extends from northeast of the Brooks Range toward the Beaufort Sea. Earthquake source mechanisms comprise a mixture of strike-slip and normal faulting events, indicative of north-northwest compression and northeast extension. A magnitude 6.4 earthquake on August 12, 2018 located 43 miles (69 km) south of Kaktovik was the largest earthquake ever recorded north of the Brooks Range. It produced an energetic aftershock sequence that continues to this day. In 2019, a vigorous swarm sequence began in the Purcell Mountains. More than 9,000 earthquakes have been recorded as part of this swarm through the end of 2021, including five earthquakes with magnitudes larger than 5. At present, this swarm continues, though at a decreased activity level.