5.5

M5.5 Earthquake 92 km S of Nikolski, AlaskaMarch 5, 2026

2026-03-05 19:25:07 UTC (2026-03-05) · approx. 8:25 AM UTC-11 local

Felt by 1 person across nearby locations.

MagnitudeM5.5(mww)
Time19:25 UTC8:25 AM UTC-11
Depth17.0 kmshallow crustal
Coordinates52.106°, -168.956°
Felt by1DYFI response· max MMI 3.5
Status✓ Reviewed by USGS· Tsunami evaluation· green PAGER
green Alertno significant casualties or damage expected
Tsunami Warning Issued

On March 5, 2026 at 19:25 UTC, a magnitude 5.5 shallow crustal earthquake struck 92 km S of Nikolski, Alaska, at a depth of 17.0 km and coordinates 52.1060°, -168.9557°. The earthquake was reported felt by 1 personacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 3.5 (light). The USGS PAGER system issued a green alert level for this event, indicating no significant casualties or damage expected. This earthquake was detected by 124 seismic stations with good location accuracy and was assigned a USGS significance rating of 466, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 5.5 releases seismic energy equivalent to roughly 3 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 3.8 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 52.11°, -168.96°

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 M5.5 earthquake near 92 km S 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 1 citizen response 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 M5.5 earthquake near 92 km S of Nikolski, Alaska

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

Population exposure (USGS PAGER)

Estimated population that experienced each level of shaking. Based on the USGS PAGER rapid impact assessment, which combines ShakeMap output with global population grids.

Shaking intensity (MMI)DescriptionPopulation exposed
MMI 3weak2

Earthquake Details

Magnitude
5.5 mww
Depth
17.0 km
shallow crustal
Location
52.1060°N
-168.9557°E
Felt Reports
1
DYFI responses
Intensity (MMI)
3.5
light
Community Intensity
2.0
CDI from reports

Technical Information

Event ID
us7000s2bn
Event Type
earthquake
Status
✓ Reviewed
Significance
466
Stations Used
124
Azimuthal Gap
111.0°
Min Station Distance
0.828°
RMS Residual
1.04 sec
Last Updated
2026-05-14 19:35:18 UTC

Common Questions

How strong was the magnitude 5.5 earthquake near Nikolski, Alaska?

The magnitude 5.5 earthquake that struck 92 km S of Nikolski, Alaska on March 5, 2026 at 19:25 UTC had a depth of 17.0 km. It was felt by 1 person with maximum shaking intensity of MMI 3.5 (light). For context, this was a moderate earthquake that could be widely felt.

Where did the earthquake occur?

The earthquake epicenter was located at 52.1060°, -168.9557°, which is 92 km S of Nikolski, Alaska. View all earthquakes in Alaska.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.5 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 5.5 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: us7000s2bn). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, March 5, 2026). M5.5 Earthquake 92 km S of Nikolski, AlaskaMarch 5, 2026. Retrieved May 20, 2026 from https://www.earthquaketracker.org/earthquakes/event/us7000s2bn/