3.7

M3.7 Earthquake 148 km SE of Sand Point, AlaskaDecember 14, 2021

2021-12-14 19:06:01 UTC (2021-12-14) · approx. 8:06 AM UTC-11 local

MagnitudeM3.7(mb)
Time19:06 UTC8:06 AM UTC-11
Depth18.7 kmshallow crustal
Coordinates54.388°, -158.866°
Felt byNo felt reports
Status✓ Reviewed by USGS

On December 14, 2021 at 19:06 UTC, a magnitude 3.7 shallow crustal earthquake struck 148 km SE of Sand Point, Alaska, at a depth of 18.7 km and coordinates 54.3882°, -158.8657°.

Physical scale: An earthquake of magnitude 3.7 releases seismic energy equivalent to roughly 5.4 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 215 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 54.39°, -158.87°

Earthquake Details

Magnitude
3.7 mb
Depth
18.7 km
shallow crustal
Location
54.3882°N
-158.8657°E

Technical Information

Event ID
us6000gd5b
Event Type
earthquake
Status
✓ Reviewed
Significance
211
Azimuthal Gap
196.0°
Min Station Distance
0.611°
RMS Residual
1.37 sec
Last Updated
2022-02-24 21:02:19 UTC

Common Questions

How strong was the magnitude 3.7 earthquake near Sand Point, Alaska?

The magnitude 3.7 earthquake that struck 148 km SE of Sand Point, Alaska on December 14, 2021 at 19:06 UTC had a depth of 18.7 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 3.7 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 3.7 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: us6000gd5b). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2021, December 14, 2021). M3.7 Earthquake 148 km SE of Sand Point, AlaskaDecember 14, 2021. Retrieved February 24, 2022 from https://www.earthquaketracker.org/earthquakes/event/us6000gd5b/