3.0

M3.0 Earthquake 133 km SSE of Sand Point, Alaska — December 29, 2020

2020-12-29 20:31:26 UTC (2020-12-29) · approx. 9:31 AM UTC-11 local

MagnitudeM3.0(ml)
Time20:31 UTC≈ 9:31 AM UTC-11
Depth24.4 kmshallow crustal
Coordinates54.254°, -159.597°
Felt byNo felt reports
Status✓ Reviewed by USGS

On December 29, 2020 at 20:31 UTC, a magnitude 3.0 shallow crustal earthquake struck 133 km SSE of Sand Point, Alaska, at a depth of 24.4 km and coordinates 54.2537°, -159.5975°.

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.

Map showing earthquake epicenter at 54.25°, -159.60°

Earthquake Details

Magnitude
3.0 ml
Depth
24.4 km
shallow crustal
Location
54.2537°N
-159.5975°E

Technical Information

Event ID
us6000d7j0
Event Type
earthquake
Status
✓ Reviewed
Significance
138
Azimuthal Gap
213.0°
Min Station Distance
0.578°
RMS Residual
0.26 sec
Last Updated
2021-03-06 23:20:25 UTC

Common Questions

How strong was the magnitude 3.0 earthquake near Sand Point, Alaska?

The magnitude 3.0 earthquake that struck 133 km SSE of Sand Point, Alaska on December 29, 2020 at 20:31 UTC had a depth of 24.4 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.

Understanding This Data

Magnitude 3.0 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: us6000d7j0). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2020, December 29, 2020). M3.0 Earthquake 133 km SSE of Sand Point, Alaska — December 29, 2020. Retrieved March 6, 2021 from https://www.earthquaketracker.org/earthquakes/event/us6000d7j0/