M3.1 Earthquake 91 km W of Adak, Alaska — February 15, 2023
2023-02-15 21:08:33 UTC (2023-02-15) · approx. 9:08 AM UTC-12 local
On February 15, 2023 at 21:08 UTC, a magnitude 3.1 shallow crustal earthquake struck 91 km W of Adak, Alaska, at a depth of 11.5 km and coordinates 51.7252°, -177.9443°.
Physical scale: An earthquake of magnitude 3.1 releases seismic energy equivalent to roughly 674 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 83 m — a useful intuition for the size of the slip patch on the fault.

Earthquake Details
-177.9443°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 3.1 earthquake near Adak, Alaska?
The magnitude 3.1 earthquake that struck 91 km W of Adak, Alaska on February 15, 2023 at 21:08 UTC had a depth of 11.5 km. For context, this was a minor earthquake typically detected only by instruments.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.1 earthquakes can continue for several days and gradually diminish over time.
Actions
Understanding This Data
Magnitude 3.1 earthquakes are typically only recorded by instruments.
Authoritative source: USGS event page (event ID: us6000jr6t). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2023, February 15, 2023). M3.1 Earthquake 91 km W of Adak, Alaska — February 15, 2023. Retrieved January 18, 2024 from https://www.earthquaketracker.org/earthquakes/event/us6000jr6t/