M5.1 Earthquake 79 km SE of Atka, Alaska — December 1, 2025
2025-12-01 22:21:07 UTC (2025-12-01) · approx. 10:21 AM UTC-12 local
Felt by 2 people across nearby locations.
On December 1, 2025 at 22:21 UTC, a magnitude 5.1 shallow crustal earthquake struck 79 km SE of Atka, Alaska, at a depth of 35.0 km and coordinates 51.6480°, -173.4586°. This earthquake was detected by 95 seismic stations with good location accuracy and was assigned a USGS significance rating of 401, placing it among routine seismic activity.
Physical scale: An earthquake of magnitude 5.1 releases seismic energy equivalent to roughly 674 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 2.0 km — a useful intuition for the size of the slip patch on the fault.
The epicenter is located in Alaska, a region characterized by Pacific Plate subduction beneath the North American Plate, producing frequent megathrust and crustal earthquakes along the Aleutian arc. The nearest mapped fault system is the Aleutian megathrust. View all earthquakes in Alaska.
Learn more: Magnitude scale · Aftershock sequences
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 2 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.
Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report
Earthquake Details
-173.4586°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 5.1 earthquake near Atka, Alaska?
The magnitude 5.1 earthquake that struck 79 km SE of Atka, Alaska on December 1, 2025 at 22:21 UTC had a depth of 35.0 km. For context, this was a moderate earthquake that could be widely felt.
Where did the earthquake occur?
The earthquake epicenter was located at 51.6480°, -173.4586°, which is 79 km SE of Atka, Alaska. View all earthquakes in Alaska.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.1 earthquakes can continue for days to weeks and gradually diminish over time.
Has Alaska had earthquakes this big before?
The largest recorded earthquake in Alaska was the M9.2 Great Alaska earthquake of March 27, 1964. Today's magnitude 5.1 event is significantly smaller than that historical record.
What should I do after an earthquake?
If you were in the affected area: check yourself and others for injuries, inspect your home for damage, and be prepared for aftershocks. For detailed guidance, see our earthquake safety guide and emergency planning resources.
Authoritative source: USGS event page (event ID: us7000rez4). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, December 1, 2025). M5.1 Earthquake 79 km SE of Atka, Alaska — December 1, 2025. Retrieved May 24, 2026 from https://www.earthquaketracker.org/earthquakes/event/us7000rez4/