M3.2 Earthquake 55 km NNW of Yakutat, Alaska — September 21, 2021
2021-09-21 21:00:16 UTC (2021-09-21) · approx. 12:00 PM UTC-9 local
On September 21, 2021 at 21:00 UTC, a magnitude 3.2 shallow crustal earthquake struck 55 km NNW of Yakutat, Alaska, at a depth of 9.2 km and coordinates 59.9902°, -140.1647°.
Physical scale: An earthquake of magnitude 3.2 releases seismic energy equivalent to roughly 951 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 97 m — a useful intuition for the size of the slip patch on the fault.
Earthquake Details
-140.1647°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 3.2 earthquake near Yakutat, Alaska?
The magnitude 3.2 earthquake that struck 55 km NNW of Yakutat, Alaska on September 21, 2021 at 21:00 UTC had a depth of 9.2 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 3.2 earthquakes can continue for several days and gradually diminish over time.
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Understanding This Data
Magnitude 3.2 earthquakes are typically only recorded by instruments.
Authoritative source: USGS event page (event ID: ak021c4ydr94). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, September 21, 2021). M3.2 Earthquake 55 km NNW of Yakutat, Alaska — September 21, 2021. Retrieved December 3, 2021 from https://www.earthquaketracker.org/earthquakes/event/ak021c4ydr94/