4.0

M4.0 Earthquake 65 km NNW of Nikolski, Alaska — October 23, 2026

2026-10-23 23:08:25 UTC (7 hours ago) · approx. 12:08 PM UTC-11 local

MagnitudeM4.0(ml)
Time23:08 UTC≈ 12:08 PM UTC-11
Depth242.9 kmintermediate depth
Coordinates53.502°, -169.170°
Felt byNo felt reports
Status✓ Reviewed by USGS

On October 23, 2026 at 23:08 UTC, a magnitude 4.0 intermediate depth earthquake struck 65 km NNW of Nikolski, Alaska, at a depth of 242.9 km and coordinates 53.5020°, -169.1700°.

Physical scale: An earthquake of magnitude 4.0 releases seismic energy equivalent to roughly 15 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 347 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 53.50°, -169.17°

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 M4.0 earthquake near 65 km NNW of Nikolski, Alaska

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

Earthquake Details

Magnitude
4.0 ml
Depth
242.9 km
intermediate depth
Location
53.5020°N
-169.1700°E
Intensity (MMI)
1.0
weak

Technical Information

Event ID
aka2026vaqtor
Event Type
earthquake
Status
✓ Reviewed
Significance
246
Stations Used
216
Azimuthal Gap
114.0°
Min Station Distance
0.500°
RMS Residual
1.10 sec
Last Updated
2026-10-24 05:39:32 UTC

Common Questions

How strong was the magnitude 4.0 earthquake near Nikolski, Alaska?

The magnitude 4.0 earthquake that struck 65 km NNW of Nikolski, Alaska on October 23, 2026 at 23:08 UTC had a depth of 242.9 km. For context, this was a light earthquake commonly felt near the epicenter.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.0 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 4.0 earthquakes are often felt but rarely cause damage.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: aka2026vaqtor). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, October 23, 2026). M4.0 Earthquake 65 km NNW of Nikolski, Alaska — October 23, 2026. Retrieved October 24, 2026 from https://www.earthquaketracker.org/earthquakes/event/aka2026vaqtor/