5.1

M5.1 Earthquake 49 km S of Akutan, AlaskaOctober 17, 2025

2025-10-17 15:48:49 UTC (2025-10-17) · approx. 4:48 AM UTC-11 local

Felt by 20 people across nearby locations.

MagnitudeM5.1(mww)
Time15:48 UTC4:48 AM UTC-11
Depth85.1 kmintermediate depth
Coordinates53.688°, -165.843°
Felt by20DYFI responses· max MMI 3.4
Status✓ Reviewed by USGS· Tsunami evaluation
Tsunami Warning Issued

On October 17, 2025 at 15:48 UTC, a magnitude 5.1 intermediate depth earthquake struck 49 km S of Akutan, Alaska, at a depth of 85.1 km and coordinates 53.6880°, -165.8432°. The earthquake was reported felt by 20 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 3.4 (light). This earthquake was detected by 127 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 407, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 5.1 releases seismic energy equivalent to roughly 674 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 2.0 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 53.69°, -165.84°

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 M5.1 earthquake near 49 km S of Akutan, Alaska

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

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 20 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.

USGS DYFI community-reported intensity map for the M5.1 earthquake near 49 km S of Akutan, Alaska

Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report

Earthquake Details

Magnitude
5.1 mww
Depth
85.1 km
intermediate depth
Location
53.6880°N
-165.8432°E
Felt Reports
20
DYFI responses
Intensity (MMI)
3.4
light
Community Intensity
3.2
CDI from reports

Technical Information

Event ID
us6000rhss
Event Type
earthquake
Status
✓ Reviewed
Significance
407
Stations Used
127
Azimuthal Gap
49.0°
Min Station Distance
0.415°
RMS Residual
0.77 sec
Last Updated
2026-05-22 15:58:57 UTC

Common Questions

How strong was the magnitude 5.1 earthquake near Akutan, Alaska?

The magnitude 5.1 earthquake that struck 49 km S of Akutan, Alaska on October 17, 2025 at 15:48 UTC had a depth of 85.1 km. It was felt by 20 people with maximum shaking intensity of MMI 3.4 (light). For context, this was a moderate earthquake that could be widely felt.

Where did the earthquake occur?

The earthquake epicenter was located at 53.6880°, -165.8432°, which is 49 km S of Akutan, Alaska. View all earthquakes in Alaska.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.1 earthquakes can continue for days to weeks 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 5.1 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: us6000rhss). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, October 17, 2025). M5.1 Earthquake 49 km S of Akutan, AlaskaOctober 17, 2025. Retrieved May 27, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000rhss/