A magnitude 3.8 earthquake struck on November 9, 2025, 17 miles southeast of Talkeetna, Alaska. This seismic event occurred at 10:23 PM AKST, translating to 07:23 AM UTC the following day. The tremor was recorded at a depth of 24.8 miles (40 km).
Impact and Areas Affected
The earthquake was felt in various locations, including:
- Talkeetna
- Anchorage
- Chugiak
In addition to these communities, residents from surrounding areas also reported sensations of shaking, including places as far away as:
- Hatcher Pass (30 miles NW)
- Willow (32 miles N)
- Sutton (41 miles NW)
- Wasilla (42 miles N)
- Palmer (44 miles NW)
- Skwentna (50 miles E)
- Eagle River (59 miles N)
- Fort Richardson (63 miles N)
- Elmendorf AFB (64 miles N)
- Anchorage (66 miles N)
- Fairbanks (194 miles S)
Tectonic Setting of Southern Alaska
Alaska’s earthquake activity is primarily influenced by several tectonic factors. The most powerful earthquakes in the region stem from the megathrust fault where the Pacific Plate subducts beneath the North American Plate. This fault was responsible for the 1964 M9.2 Great Alaska Earthquake, the second-largest ever recorded globally.
Intermediate-Depth Seismicity
Intermediate-depth events are reported below 20 miles (32 km) within the Wadati-Benioff Zone. Within this zone, the Pacific Plate descends toward the mantle under the North American Plate. Major seismic incidents, like the 2016 M7.1 Iniskin quake and the 2018 M7.1 Anchorage quake, contributed to significant ground shaking and structural damage.
Crustal Seismicity Sources
Crustal seismicity in Southern Alaska derives from various geological features:
- Cook Inlet basin faults and folds
- The Castle Mountain Fault
- A diffuse seismicity band extending from northern Cook Inlet to the Denali Fault
The April 1933 M6.9 earthquake, which caused considerable damage in Anchorage, likely originated from geological structures in the Cook Inlet area. Similarly, the 1984 M5.6 Sutton earthquake arose from the Castle Mountain Fault.
This earthquake serves as a reminder of Alaska’s active tectonic environment and the potential risks posed by seismic events.
