Skip to content
SeismoAtlas

M3.5 earthquake – Nikolski, Alaska

A magnitude 3.5 earthquake struck in the Nikolski, Alaska region at 09:25 UTC on 4 Sept 2026, at a depth of 12 km, according to USGS.

Data: USGS · updated 2026-09-04 15:37 UTC · reviewed

Magnitude
3.5minor
local magnitude (Richter) (ml)
Depth
12.3 km
Status
Reviewed
Origin time
2026-09-04 09:25:21 UTC
Epicentre
52.187° N, 169.246° W

Circles show this event and others within 30 km from 7 days before to 30 days after. Lines: plate boundaries and GEM active faults. Open on the live map

Nearby places

Distance and estimated shaking at nearby places
PlaceDistanceEst. shaking
No towns within 400 km. This is a remote area.

Shaking is an estimate from the intensity prediction equation of Allen, Wald & Worden (2012), not an observation. Local ground and buildings can change it by a level or more. Likely felt out to about 23 km.

Every agency's solution

Agencies locate earthquakes with their own stations and methods, so their numbers differ. We match reports of the same event by time, distance and magnitude and show them side by side. The headline uses USGS · AK, which has been reviewed by an analyst.

AgencyMagnitudeDepthEpicentreTime offsetStatus
USGS · AKheadlineAlaska Earthquake Center via U.S. Geological Survey3.5 ml12.3 km52.19° N, 169.25° W–Reviewed

How big was it?

Often felt by people at rest close to the epicentre, rarely causes damage.

It released roughly the energy of 2.7 t of TNT. Magnitude is logarithmic: each whole step means about 32 times more energy and 10 times larger waves on a seismogram. Depth matters too: at 12 km this was a shallow earthquake, which is felt more strongly at the surface than a deeper one of the same size.

M3.5 releases about 32× the energy of M2.5, and its waves are about 10× taller on a seismogram. Energy: 2.7 t of TNT vs 85 kg of TNT.

Each square is the energy of one M2.5. Energy from log₁₀E = 1.5M + 4.8.

Aftershocks and nearby activity

81 later earthquakes within 30 km; the largest was M4.9 23 days ago. 171 in the 7 days before. Aftershock rates usually fall off roughly in proportion to 1/time.

Aftershocks

Mainshock M3.5

81 later earthquakes nearby. Aftershock rates typically fall off roughly as 1/time (Omori's law).

Aftershocks
Time after mainshock (hours)MagnitudeDepth (km)
0.973.215
2.202.711
2.632.635
4.722.810
5.244.035
5.453.135
6.142.910
8.072.625
16.593.129
17.543.217
17.853.010
18.302.810
18.742.535
18.892.727
20.882.710
23.732.714
24.552.720
27.032.810
29.413.07
30.742.75
30.823.020
32.584.929
32.772.820
39.692.88
42.953.825
43.022.922
43.752.810
46.392.821
47.642.91
49.882.917
51.092.818
53.563.110
54.053.910
59.822.711
61.252.711
62.452.813
65.043.210
65.892.612
71.832.711
75.672.713
75.822.722
76.882.735
93.433.015
94.793.28
94.862.95
104.513.210
104.583.410
105.032.610
105.452.710
108.692.914
109.624.046
109.643.38
109.722.77
109.883.09
110.032.713
110.962.712
110.973.650
115.112.611
137.082.511
150.912.735
161.473.411
164.932.98
165.982.718
166.082.719
174.762.614
176.993.135
200.853.335
205.842.539
222.492.85
227.262.716
227.622.935
253.442.710
263.292.98
272.342.952
272.592.818
311.782.714
327.713.825
363.314.041
380.533.211
380.592.910
540.104.035
  1. 4.9Nikolski, Alaska09-05 18:00
  2. 4.0Nikolski, Alaska09-04 14:39
  3. 4.0Nikolski, Alaska09-08 23:02
  4. 4.0Nikolski, Alaska09-19 12:44
  5. 4.0Fox Islands, Aleutian Islands09-26 21:31
  6. 3.9Nikolski, Alaska09-06 15:28
  7. 3.8Nikolski, Alaska09-06 04:22
  8. 3.8Nikolski, Alaska09-18 01:07
  9. 3.6Nikolski, Alaska09-09 00:23
  10. 3.4Nikolski, Alaska09-08 18:00
  11. 3.4Nikolski, Alaska09-11 02:53
  12. 3.3Nikolski, Alaska09-08 23:04
  13. 3.3Nikolski, Alaska09-12 18:16
  14. 3.2Nikolski, Alaska09-04 10:23
  15. 3.2Nikolski, Alaska09-05 02:57
  16. 3.2Nikolski, Alaska09-07 02:28
  17. 3.2Nikolski, Alaska09-08 08:13
  18. 3.2Nikolski, Alaska09-08 17:55
  19. 3.2Nikolski, Alaska09-20 05:57
  20. 3.1Nikolski, Alaska09-04 14:52
  21. 3.1Nikolski, Alaska09-05 02:00
  22. 3.1Nikolski, Alaska09-06 14:58
  23. 3.1Nikolski, Alaska09-11 18:24
  24. 3.0Nikolski, Alaska09-05 03:16
  25. 3.0Nikolski, Alaska09-05 14:49

Did you feel it?

Reports from people help show where shaking was strong. They are anonymous and shown here in aggregate.

Reports close 14 days after an earthquake.

Reports on SeismoAtlas

No reports yet.

Event id aka2026rncfrf. First recorded here 28 Sept 2026, 17:32:13 UTC. Solutions: USGS · AK (usgs:aka2026rncfrf). Cite as: SeismoAtlas, “M3.5 earthquake – Nikolski, Alaska”, https://seismoatlas.com/earthquake/aka2026rncfrf-m3-5-earthquake-nikolski-alaska, data from USGS.

JSON: /api/v1/events/aka2026rncfrf. SeismoAtlas is not an official warning service.