M4.3 Earthquake 124 km SW of Adak, Alaska — November 21, 2025
2025-11-21 18:49:40 UTC (2025-11-21) · approx. 6:49 AM UTC-12 local
On November 21, 2025 at 18:49 UTC, a magnitude 4.3 shallow crustal earthquake struck 124 km SW of Adak, Alaska, at a depth of 45.6 km and coordinates 51.2312°, -178.1051°.
Physical scale: An earthquake of magnitude 4.3 releases seismic energy equivalent to roughly 43 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 558 m — a useful intuition for the size of the slip patch on the fault.
Earthquake Details
-178.1051°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 4.3 earthquake near Adak, Alaska?
The magnitude 4.3 earthquake that struck 124 km SW of Adak, Alaska on November 21, 2025 at 18:49 UTC had a depth of 45.6 km. For context, this was a light earthquake commonly felt near the epicenter.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.3 earthquakes can continue for several days and gradually diminish over time.
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.
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Understanding This Data
Magnitude 4.3 earthquakes are often felt but rarely cause damage.
Authoritative source: USGS event page (event ID: us6000rpp4). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, November 21, 2025). M4.3 Earthquake 124 km SW of Adak, Alaska — November 21, 2025. Retrieved May 25, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000rpp4/