6.5

M6.5 Earthquake 177 km W of Nikolski, Alaska — September 17, 2026

2026-09-17 14:19:52 UTC (2026-09-17) · approx. 3:19 AM UTC-11 local

Felt by 8 people across nearby locations. Maximum shaking intensity MMI 4.8 (moderate).

MagnitudeM6.5(mww)
Time14:19 UTC≈ 3:19 AM UTC-11
Depth98.0 kmintermediate depth
Coordinates52.956°, -171.503°
Felt by8DYFI responses· max MMI 4.8
Status✓ Reviewed by USGS· Tsunami evaluation· green PAGER
green Alert— no significant casualties or damage expected
Tsunami Warning Issued

On September 17, 2026 at 14:19 UTC, a magnitude 6.5 intermediate depth earthquake struck 177 km W of Nikolski, Alaska, at a depth of 98.0 km and coordinates 52.9564°, -171.5033°. The earthquake was reported felt by 8 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 4.8 (moderate). The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. This earthquake was detected by 150 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 653, making it a moderate-impact event.

Physical scale: An earthquake of magnitude 6.5 releases seismic energy equivalent to roughly 85 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 18 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 52.96°, -171.50°

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 M6.5 earthquake near 177 km W of Nikolski, Alaska

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

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 8 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 M6.5 earthquake near 177 km W of Nikolski, Alaska

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

Earthquake Details

Magnitude
6.5 mww
Depth
98.0 km
intermediate depth
Location
52.9564°N
-171.5033°E
Felt Reports
8
DYFI responses
Intensity (MMI)
4.8
moderate
Community Intensity
3.4
CDI from reports

Technical Information

Event ID
us7000ti1p
Event Type
earthquake
Status
✓ Reviewed
Significance
653
Stations Used
150
Azimuthal Gap
29.0°
Min Station Distance
0.899°
RMS Residual
0.99 sec
Last Updated
2026-10-15 14:29:55 UTC

Common Questions

How strong was the magnitude 6.5 earthquake near Nikolski, Alaska?

The magnitude 6.5 earthquake that struck 177 km W of Nikolski, Alaska on September 17, 2026 at 14:19 UTC had a depth of 98.0 km. It was felt by 8 people with maximum shaking intensity of MMI 4.8 (moderate). For context, this was a strong earthquake capable of causing significant damage.

Where did the earthquake occur?

The earthquake epicenter was located at 52.9564°, -171.5033°, which is 177 km W of Nikolski, Alaska. View all earthquakes in Alaska.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 6.5 earthquakes can continue for weeks to months 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 6.5 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us7000ti1p). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, September 17, 2026). M6.5 Earthquake 177 km W of Nikolski, Alaska — September 17, 2026. Retrieved October 15, 2026 from https://www.earthquaketracker.org/earthquakes/event/us7000ti1p/