Reviewed by USGSAlaska1d ago
M3.8 earthquake 136 km SW of Nikolski, Alaska
Friday, September 25, 2026, 12:37:32 UTC · 52.123°N, 170.358°W
A magnitude 3.8 earthquake struck 136 km SW of Nikolski, Alaska on Friday, September 25, 2026, 12:37:32 UTC, at a depth of 23.3 km (shallow).
- Magnitude
- 3.8
- Minor · ml
- Depth
- 23 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- II
- Weak (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
8 tons of TNT
That is about 1/1,992 of the Hiroshima bomb. A magnitude 5.0 releases about 63 times more energy.
Tectonic setting
75 km
from the nearest mapped plate boundary, between the North American and Pacific plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
23 km
Shallow earthquakes (under 70 km) produce the strongest surface shaking for their size, so they are the ones most likely to cause damage near the epicenter.
Did You Feel It?
Where it was felt
No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.
I felt it — report to USGS ↗USGS PAGER estimate
Who was exposed to shaking
USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.
After the main event
Aftershocks within 50 km
USGS has not published any M2.5+ earthquake within 50 km since this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 851 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.8234 km SSW of Nikolski, AlaskaMarch 7, 1929 · 141 km S of this epicenter
- 7.881 km E of Nikolski, AlaskaJuly 2, 1965 · 208 km NE of this epicenter
- 7.4133 km WNW of Nikolski, AlaskaApril 18, 1916 · 148 km N of this epicenter
- 7.3Fox Islands, Aleutian Islands, AlaskaJune 24, 2011 · 101 km W of this epicenter
- 7.135 km SW of Nikolski, AlaskaMarch 11, 1957 · 101 km NE of this epicenter
- 6.980 km SW of Nikolski, AlaskaMarch 9, 1957 · 61 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 13 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1901M7.8
Aleutian Islands: Fox Islands
31 Dec 1901 · 88 km away
Limited damage (under $1M)tsunami
- 1965M6.5
Aleutian Islands: Fox Islands
2 Jul 1965 · 215 km away
Limited damage (under $1M)tsunami
- 1902M7.8
Aleutian Islands: Fox Islands
1 Jan 1902 · 197 km away
- 1907M7.8
Aleutian Islands
2 Sep 1907 · 67 km away
- 1929M7.8
Aleutian Islands: Fox Islands
7 Mar 1929 · 127 km away · intensity V
tsunami
- 1916M7.5
Aleutian Islands: Fox Islands
18 Apr 1916 · 133 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.