4.8

M4.8 Earthquake near Fox Islands, Aleutian Islands, AlaskaJanuary 22, 2023

2023-01-22 03:27:42 UTC (2023-01-22) · approx. 4:27 PM UTC-11 local

MagnitudeM4.8(mb)
Time03:27 UTC4:27 PM UTC-11
Depth129.2 kmintermediate depth
Coordinates53.330°, -169.299°
Felt byNo felt reports
Status✓ Reviewed by USGS

On January 22, 2023 at 03:27 UTC, a magnitude 4.8 intermediate depth earthquake struck near Fox Islands, Aleutian Islands, Alaska, at a depth of 129.2 km and coordinates 53.3295°, -169.2990°. This earthquake was detected by 112 seismic stations with good location accuracy and was assigned a USGS significance rating of 354, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 4.8 releases seismic energy equivalent to roughly 239 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.2 km — a useful intuition for the size of the slip patch on the fault.

The epicenter is located in Alaska, a region characterized by Pacific Plate subduction beneath the North American Plate, producing frequent megathrust and crustal earthquakes along the Aleutian arc. The nearest mapped fault system is the Aleutian megathrust. View all earthquakes in Alaska.

Learn more: Magnitude scale · Aftershock sequences

Map showing earthquake epicenter at 53.33°, -169.30°

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 M4.8 earthquake near Fox Islands, Aleutian Islands, Alaska

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

Earthquake Details

Magnitude
4.8 mb
Depth
129.2 km
intermediate depth
Location
53.3295°N
-169.2990°E
Intensity (MMI)
3.2
light

Technical Information

Event ID
us7000j65z
Event Type
earthquake
Status
✓ Reviewed
Significance
354
Stations Used
112
Azimuthal Gap
107.0°
Min Station Distance
0.682°
RMS Residual
0.82 sec
Last Updated
2023-04-11 18:51:51 UTC

Common Questions

How strong was the magnitude 4.8 earthquake near Fox Islands, Aleutian Islands, Alaska?

The magnitude 4.8 earthquake that struck near Fox Islands, Aleutian Islands, Alaska on January 22, 2023 at 03:27 UTC had a depth of 129.2 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at 53.3295°, -169.2990°, which is near Fox Islands, Aleutian Islands, Alaska. View all earthquakes in Alaska.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.8 earthquakes can continue for several days and gradually diminish over time.

Has Alaska had earthquakes this big before?

The largest recorded earthquake in Alaska was the M9.2 Great Alaska earthquake of March 27, 1964. Today's magnitude 4.8 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us7000j65z). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, January 22, 2023). M4.8 Earthquake near Fox Islands, Aleutian Islands, AlaskaJanuary 22, 2023. Retrieved April 11, 2023 from https://www.earthquaketracker.org/earthquakes/event/us7000j65z/