3.5

M3.5 Earthquake 87 km SSW of Nikolski, AlaskaSeptember 1, 2026

2026-09-01 07:26:51 UTC (12 hours ago) · approx. 8:26 PM UTC-11 local

MagnitudeM3.5(ml)
Time07:26 UTC8:26 PM UTC-11
Depth14.9 kmshallow crustal
Coordinates52.198°, -169.306°
Felt byNo felt reports
Status✓ Reviewed by USGS

On September 1, 2026 at 07:26 UTC, a magnitude 3.5 shallow crustal earthquake struck 87 km SSW of Nikolski, Alaska, at a depth of 14.9 km and coordinates 52.1980°, -169.3060°.

Physical scale: An earthquake of magnitude 3.5 releases seismic energy equivalent to roughly 2.7 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 157 m — a useful intuition for the size of the slip patch on the fault.

This earthquake is part of an ongoing aftershock sequence following the magnitude 5.3 mainshock that occurred 13 hours ago 89 km SSW of Nikolski, Alaska. Since the mainshock, the USGS has recorded 24 aftershocks in this area. Aftershock activity is expected to continue for days to weeks as stresses on surrounding faults redistribute.

Map showing earthquake epicenter at 52.20°, -169.31°

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 M3.5 earthquake near 87 km SSW of Nikolski, Alaska

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

Earthquake Details

Magnitude
3.5 ml
Depth
14.9 km
shallow crustal
Location
52.1980°N
-169.3060°E
Intensity (MMI)
1.6
weak

Technical Information

Event ID
aka2026rhkflj
Event Type
earthquake
Status
✓ Reviewed
Significance
188
Stations Used
32
Azimuthal Gap
222.0°
Min Station Distance
0.600°
RMS Residual
0.60 sec
Last Updated
2026-09-01 20:02:39 UTC

Common Questions

How strong was the magnitude 3.5 earthquake near Nikolski, Alaska?

The magnitude 3.5 earthquake that struck 87 km SSW of Nikolski, Alaska on September 1, 2026 at 07:26 UTC had a depth of 14.9 km. For context, this was a minor earthquake typically detected only by instruments.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.5 earthquakes can continue for several days and gradually diminish over time.

Is this the same earthquake as the M5.3 one earlier?

No. This magnitude 3.5 earthquake is an aftershock of the larger magnitude 5.3 mainshock that occurred earlier 89 km SSW of Nikolski, Alaska. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.

Understanding This Data

Magnitude 3.5 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: aka2026rhkflj). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, September 1, 2026). M3.5 Earthquake 87 km SSW of Nikolski, AlaskaSeptember 1, 2026. Retrieved September 1, 2026 from https://www.earthquaketracker.org/earthquakes/event/aka2026rhkflj/