5.3

M5.3 Earthquake 168 km SW of Nikolski, AlaskaMay 23, 2026

2026-05-23 21:49:16 UTC (2 hours ago) · approx. 10:49 AM UTC-11 local

MagnitudeM5.3(mww)
Time21:49 UTC10:49 AM UTC-11
Depth7.2 kmshallow crustal
Coordinates51.734°, -170.349°
Felt byNo felt reports
Status✓ Reviewed by USGS

On May 23, 2026 at 21:49 UTC, a magnitude 5.3 shallow crustal earthquake struck 168 km SW of Nikolski, Alaska, at a depth of 7.2 km and coordinates 51.7344°, -170.3491°. This earthquake was detected by 107 seismic stations with good location accuracy and was assigned a USGS significance rating of 432, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 5.3 releases seismic energy equivalent to roughly 1 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 2.7 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 51.73°, -170.35°

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 M5.3 earthquake near 168 km SW of Nikolski, Alaska

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

Earthquake Details

Magnitude
5.3 mww
Depth
7.2 km
shallow crustal
Location
51.7344°N
-170.3491°E
Intensity (MMI)
3.3
light

Technical Information

Event ID
us6000szt5
Event Type
earthquake
Status
✓ Reviewed
Significance
432
Stations Used
107
Azimuthal Gap
143.0°
Min Station Distance
1.122°
RMS Residual
1.33 sec
Last Updated
2026-05-23 22:49:30 UTC

Common Questions

How strong was the magnitude 5.3 earthquake near Nikolski, Alaska?

The magnitude 5.3 earthquake that struck 168 km SW of Nikolski, Alaska on May 23, 2026 at 21:49 UTC had a depth of 7.2 km. For context, this was a moderate earthquake that could be widely felt.

Where did the earthquake occur?

The earthquake epicenter was located at 51.7344°, -170.3491°, which is 168 km SW of Nikolski, Alaska. View all earthquakes in Alaska.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.3 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 5.3 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: us6000szt5). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, May 23, 2026). M5.3 Earthquake 168 km SW of Nikolski, AlaskaMay 23, 2026. Retrieved May 23, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000szt5/