M3.0 Earthquake 143 km SW of Nikolski, Alaska — July 21, 2026
2026-07-21 03:40:10 UTC (2 days ago) · approx. 4:40 PM UTC-11 local
On July 21, 2026 at 03:40 UTC, a magnitude 3.0 shallow crustal earthquake struck 143 km SW of Nikolski, Alaska, at a depth of 27.4 km and coordinates 52.0520°, -170.3940°.
Physical scale: An earthquake of magnitude 3.0 releases seismic energy equivalent to roughly 477 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 71 m — a useful intuition for the size of the slip patch on the fault.
Earthquake Details
-170.3940°E
Technical Information
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Common Questions
How strong was the magnitude 3.0 earthquake near Nikolski, Alaska?
The magnitude 3.0 earthquake that struck 143 km SW of Nikolski, Alaska on July 21, 2026 at 03:40 UTC had a depth of 27.4 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 3.0 earthquakes can continue for several days and gradually diminish over time.
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Understanding This Data
Magnitude 3.0 earthquakes are typically only recorded by instruments.
Authoritative source: USGS event page (event ID: aka2026ohntcy). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2026, July 21, 2026). M3.0 Earthquake 143 km SW of Nikolski, Alaska — July 21, 2026. Retrieved July 23, 2026 from https://www.earthquaketracker.org/earthquakes/event/aka2026ohntcy/