Reviewed by USGSAlaska25d ago
M5.3 earthquake 90 km SSW of Nikolski, Alaska
Tuesday, September 1, 2026, 06:44:37 UTC · 52.205°N, 169.430°W
A magnitude 5.3 earthquake struck 90 km SSW of Nikolski, Alaska on Tuesday, September 1, 2026, 06:44:37 UTC, at a depth of 33.8 km (shallow). USGS received 3 “Did You Feel It?” reports, with a maximum reported intensity of V (moderate). It is the strongest earthquake within 300 km since an M5.8 on July 26, 2026.
Tsunami flagUSGS sets this flag for large events in oceanic regions so tsunami warning centers review them. It does not by itself mean a tsunami occurred. Check tsunami.gov and local authorities for official messages.
- Magnitude
- 5.3
- Moderate · mww
- Depth
- 34 km
- Shallow
- Felt reports
- 3
- Max intensity V
- Est. shaking
- III
- Weak (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- Flag
- Check tsunami.gov
Outlined circle: this earthquakeDashed circle: 75 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
1 kilotons of TNT
That is about 1/11 of the Hiroshima bomb. It released about 3 times the energy of a magnitude 5.0.
Tectonic setting
60 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
34 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
Reports sent by people to USGS, grouped by place (most reports first). Intensity uses the Modified Mercalli scale (I–X): what people felt, not the magnitude.
| Place | Intensity | Reports | Distance |
|---|---|---|---|
| 99638<br>0.311 | IV · Light | 3 | 122 km |
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 75 km
USGS lists 282 M2.5+ earthquakes within 75 km since this event; the largest was M6.3 on September 3, 2026. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 3.8136 km SW of Nikolski, Alaska1d ago · 64 km W of this epicenter
- 3.5145 km SW of Nikolski, Alaska5d ago · 74 km W of this epicenter
- 2.784 km S of Nikolski, Alaska6d ago · 46 km E of this epicenter
- 2.779 km SW of Nikolski, Alaska6d ago · 42 km NW of this epicenter
- 2.995 km SSW of Nikolski, Alaska6d ago · 23 km SE of this epicenter
- 3.296 km SSW of Nikolski, Alaska6d ago · 23 km SE of this epicenter
- 4.085 km SSW of Nikolski, Alaska7d ago · 5 km N of this epicenter
- 3.647 km WSW of Nikolski, Alaska8d ago · 65 km N of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 755 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 · 146 km S of this epicenter
- 7.881 km E of Nikolski, AlaskaJuly 2, 1965 · 150 km NE of this epicenter
- 7.4133 km WNW of Nikolski, AlaskaApril 18, 1916 · 161 km NW of this epicenter
- 7.3Fox Islands, Aleutian Islands, AlaskaJune 24, 2011 · 165 km W of this epicenter
- 7.135 km SW of Nikolski, AlaskaMarch 11, 1957 · 56 km N of this epicenter
- 7.0203 km SSE of Unalaska, AlaskaAugust 22, 1940 · 268 km E 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 · 138 km away
Limited damage (under $1M)tsunami
- 1965M6.5
Aleutian Islands: Fox Islands
2 Jul 1965 · 157 km away
Limited damage (under $1M)tsunami
- 1917M7.9
Alaska Peninsula
31 May 1917 · 288 km away · intensity V
- 1902M7.8
Aleutian Islands: Fox Islands
1 Jan 1902 · 133 km away
- 1907M7.8
Aleutian Islands
2 Sep 1907 · 47 km away
- 1929M7.8
Aleutian Islands: Fox Islands
7 Mar 1929 · 140 km away · intensity V
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.