4.6

M4.6 Earthquake 141 km S of False Pass, AlaskaMay 31, 2025

2025-05-31 22:41:06 UTC (2025-05-31) · approx. 11:41 AM UTC-11 local

MagnitudeM4.6(mb)
Time22:41 UTC11:41 AM UTC-11
Depth35.0 kmshallow crustal
Coordinates53.582°, -163.248°
Felt byNo felt reports
Status✓ Reviewed by USGS

On May 31, 2025 at 22:41 UTC, a magnitude 4.6 shallow crustal earthquake struck 141 km S of False Pass, Alaska, at a depth of 35.0 km and coordinates 53.5821°, -163.2480°. This earthquake was detected by 79 seismic stations with good location accuracy and was assigned a USGS significance rating of 326, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 4.6 releases seismic energy equivalent to roughly 120 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 899 m — 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 53.58°, -163.25°

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 M4.6 earthquake near 141 km S of False Pass, Alaska

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

Earthquake Details

Magnitude
4.6 mb
Depth
35.0 km
shallow crustal
Location
53.5821°N
-163.2480°E
Intensity (MMI)
1.8
weak

Technical Information

Event ID
us6000qh5l
Event Type
earthquake
Status
✓ Reviewed
Significance
326
Stations Used
79
Azimuthal Gap
167.0°
Min Station Distance
1.104°
RMS Residual
0.70 sec
Last Updated
2025-08-16 21:54:12 UTC

Common Questions

How strong was the magnitude 4.6 earthquake near False Pass, Alaska?

The magnitude 4.6 earthquake that struck 141 km S of False Pass, Alaska on May 31, 2025 at 22:41 UTC had a depth of 35.0 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at 53.5821°, -163.2480°, which is 141 km S of False Pass, Alaska. View all earthquakes in Alaska.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.6 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 4.6 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us6000qh5l). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, May 31, 2025). M4.6 Earthquake 141 km S of False Pass, AlaskaMay 31, 2025. Retrieved August 16, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000qh5l/