4.5

M4.5 Earthquake near Rat Islands, Aleutian Islands, AlaskaSeptember 16, 2025

2025-09-16 19:10:30 UTC (2025-09-16) · approx. 7:10 AM UTC+12 local

MagnitudeM4.5(mb)
Time19:10 UTC7:10 AM UTC+12
Depth113.1 kmintermediate depth
Coordinates51.705°, 178.150°
Felt byNo felt reports
Status✓ Reviewed by USGS

On September 16, 2025 at 19:10 UTC, a magnitude 4.5 intermediate depth earthquake struck near Rat Islands, Aleutian Islands, Alaska, at a depth of 113.1 km and coordinates 51.7045°, 178.1500°. This earthquake was detected by 92 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 312, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 4.5 releases seismic energy equivalent to roughly 85 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 767 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 51.70°, 178.15°

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 M4.5 earthquake near Rat Islands, Aleutian Islands, Alaska

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

Earthquake Details

Magnitude
4.5 mb
Depth
113.1 km
intermediate depth
Location
51.7045°N
178.1500°E
Intensity (MMI)
2.2
weak

Technical Information

Event ID
us7000qwjm
Event Type
earthquake
Status
✓ Reviewed
Significance
312
Stations Used
92
Azimuthal Gap
82.0°
Min Station Distance
0.331°
RMS Residual
0.51 sec
Last Updated
2025-12-03 03:58:46 UTC

Common Questions

How strong was the magnitude 4.5 earthquake near Rat Islands, Aleutian Islands, Alaska?

The magnitude 4.5 earthquake that struck near Rat Islands, Aleutian Islands, Alaska on September 16, 2025 at 19:10 UTC had a depth of 113.1 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at 51.7045°, 178.1500°, which is near Rat Islands, Aleutian Islands, Alaska. View all earthquakes in Alaska.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.5 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 4.5 event is significantly smaller than that historical record.

What should I do after an earthquake?

If you were in the affected area: check yourself and others for injuries, inspect your home for damage, and be prepared for aftershocks. For detailed guidance, see our earthquake safety guide and emergency planning resources.

Authoritative source: USGS event page (event ID: us7000qwjm). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, September 16, 2025). M4.5 Earthquake near Rat Islands, Aleutian Islands, AlaskaSeptember 16, 2025. Retrieved May 28, 2026 from https://www.earthquaketracker.org/earthquakes/event/us7000qwjm/