Reviewed by USGSAlaska3d ago
M3.8 earthquake 151 km S of False Pass, Alaska
Thursday, September 24, 2026, 07:22:15 UTC · 53.500°N, 163.701°W
A magnitude 3.8 earthquake struck 151 km S of False Pass, Alaska on Thursday, September 24, 2026, 07:22:15 UTC, at a depth of 9.3 km (shallow).
- Magnitude
- 3.8
- Minor · ml
- Depth
- 9 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 earthquakeDashed circle: 50 km aftershock search areaColoured 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
46 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
9 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 lists 1 M2.5+ earthquake within 50 km since this event; the largest was M3.5 on September 26, 2026. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 498 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.6The 1946 Unimak Island, Alaska EarthquakeApril 1, 1946 · 57 km E of this epicenter
- 7.881 km E of Nikolski, AlaskaJuly 2, 1965 · 268 km W of this epicenter
- 7.62020 Sand Point, Alaska EarthquakeOctober 19, 2020 · 293 km NE of this epicenter
- 7.454 km SE of Sand Point, AlaskaMay 31, 1917 · 299 km NE of this epicenter
- 7.32025 Sand Point, Alaska EarthquakeJuly 16, 2025 · 242 km NE of this epicenter
- 7.22023 Sand Point, Alaska EarthquakeJuly 16, 2023 · 216 km NE of this epicenter
- 7.190 km SE of King Cove, AlaskaMay 14, 1948 · 206 km NE of this epicenter
- 7.139 km S of Akutan, AlaskaMarch 22, 1957 · 140 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 12 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 169 recorded deaths. The most severe:
- 1946M8.6
Unimak Island
1 Apr 1946 · 57 km away · intensity VI
168 deaths$26 million damagetsunami
- 2023M7.2
Alaska Peninsula
16 Jul 2023 · 220 km away · intensity VI
1 deathtsunami
- 1965M6.5
Aleutian Islands: Fox Islands
2 Jul 1965 · 261 km away
Limited damage (under $1M)tsunami
- 1788M8.0
Alaska Peninsula
6 Aug 1788 · 242 km away
tsunami
- 1902M7.8
Aleutian Islands: Fox Islands
1 Jan 1902 · 282 km away
- 2020M7.6
Alaska
19 Oct 2020 · 293 km away · intensity IX
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.