M3.2 Earthquake 113 km E of Chignik, Alaska — October 12, 2021
2021-10-12 18:47:57 UTC (2021-10-12) · approx. 8:47 AM UTC-10 local
On October 12, 2021 at 18:47 UTC, a magnitude 3.2 shallow crustal earthquake struck 113 km E of Chignik, Alaska, at a depth of 46.5 km and coordinates 56.3557°, -156.5665°.
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
-156.5665°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 3.2 earthquake near Chignik, Alaska?
The magnitude 3.2 earthquake that struck 113 km E of Chignik, Alaska on October 12, 2021 at 18:47 UTC had a depth of 46.5 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 3.2 earthquakes can continue for several days and gradually diminish over time.
Actions
Understanding This Data
Magnitude 3.2 earthquakes are typically only recorded by instruments.
Authoritative source: USGS event page (event ID: ak021d3n5wqy). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, October 12, 2021). M3.2 Earthquake 113 km E of Chignik, Alaska — October 12, 2021. Retrieved December 18, 2021 from https://www.earthquaketracker.org/earthquakes/event/ak021d3n5wqy/