4.1

M4.1 Earthquake 71 km SW of Kaktovik, AlaskaJanuary 23, 2023

2023-01-23 21:44:39 UTC (2023-01-23) · approx. 11:44 AM UTC-10 local

MagnitudeM4.1(mwr)
Time21:44 UTC11:44 AM UTC-10
Depth23.4 kmshallow crustal
Coordinates69.605°, -144.698°
Felt byNo felt reports
Status✓ Reviewed by USGS· Tsunami evaluation
Tsunami Warning Issued

On January 23, 2023 at 21:44 UTC, a magnitude 4.1 shallow crustal earthquake struck 71 km SW of Kaktovik, Alaska, at a depth of 23.4 km and coordinates 69.6054°, -144.6979°.

Physical scale: An earthquake of magnitude 4.1 releases seismic energy equivalent to roughly 21 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 406 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 69.61°, -144.70°

ShakeMap — predicted shaking intensity

Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.

USGS ShakeMap intensity contours for the M4.1 earthquake near 71 km SW of Kaktovik, Alaska

Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS

Earthquake Details

Magnitude
4.1 mwr
Depth
23.4 km
shallow crustal
Location
69.6054°N
-144.6979°E
Intensity (MMI)
4.7
moderate

Technical Information

Event ID
ak02312e4ly8
Event Type
earthquake
Status
✓ Reviewed
Significance
259
RMS Residual
0.64 sec
Last Updated
2023-04-11 18:51:26 UTC

Common Questions

How strong was the magnitude 4.1 earthquake near Kaktovik, Alaska?

The magnitude 4.1 earthquake that struck 71 km SW of Kaktovik, Alaska on January 23, 2023 at 21:44 UTC had a depth of 23.4 km. For context, this was a light earthquake commonly felt near the epicenter.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.1 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 4.1 earthquakes are often felt but rarely cause damage.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: ak02312e4ly8). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, January 23, 2023). M4.1 Earthquake 71 km SW of Kaktovik, AlaskaJanuary 23, 2023. Retrieved April 11, 2023 from https://www.earthquaketracker.org/earthquakes/event/ak02312e4ly8/