Reviewed by USGSAlaska2y ago
M3.5 earthquake 81 km SSE of Akutan, Alaska
Saturday, December 30, 2023, 08:43:25 UTC · 53.458°N, 165.314°W
A magnitude 3.5 earthquake struck 81 km SSE of Akutan, Alaska on Saturday, December 30, 2023, 08:43:25 UTC, at a depth of 35.0 km (shallow).
- Magnitude
- 3.5
- Minor · ml
- Depth
- 35 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
3 tons of TNT
That is about 1/5,615 of the Hiroshima bomb. A magnitude 5.0 releases about 178 times more energy.
Tectonic setting
82 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
35 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 9 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M3.6 on January 16, 2024. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 2.648 km SE of Akutan, Alaska2y ago · 36 km N of this epicenter
- 2.583 km SE of Akutan, Alaska2y ago · 25 km NE of this epicenter
- 3.172 km SE of Unalaska, Alaska2y ago · 27 km W of this epicenter
- 2.870 km SSE of Akutan, Alaska2y ago · 16 km NE of this epicenter
- 3.689 km SE of Unalaska, Alaska2y ago · 39 km SW of this epicenter
- 3.097 km SE of Akutan, Alaska2y ago · 45 km E of this epicenter
- 3.1109 km SE of Akutan, Alaska2y ago · 48 km E of this epicenter
- 2.667 km SSE of Akutan, Alaska2y ago · 14 km NW of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 571 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 · 164 km E of this epicenter
- 7.881 km E of Nikolski, AlaskaJuly 2, 1965 · 163 km W of this epicenter
- 7.190 km SE of King Cove, AlaskaMay 14, 1948 · 299 km NE of this epicenter
- 7.139 km S of Akutan, AlaskaMarch 22, 1957 · 47 km NW of this epicenter
- 7.135 km SW of Nikolski, AlaskaMarch 11, 1957 · 273 km W of this epicenter
- 7.071 km SE of King Cove, AlaskaMay 30, 1991 · 272 km NE of this epicenter
- 7.0203 km SSE of Unalaska, AlaskaAugust 22, 1940 · 145 km S of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 9 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 168 recorded deaths. The most severe:
- 1946M8.6
Unimak Island
1 Apr 1946 · 164 km away · intensity VI
168 deaths$26 million damagetsunami
- 1965M6.5
Aleutian Islands: Fox Islands
2 Jul 1965 · 156 km away
Limited damage (under $1M)tsunami
- 1917M7.9
Alaska Peninsula
31 May 1917 · 289 km away · intensity V
- 1902M7.8
Aleutian Islands: Fox Islands
1 Jan 1902 · 188 km away
- 1957M7.5
Aleutian Islands: Fox Islands
22 Mar 1957 · 172 km away · intensity V
- 1962M6.5
Aleutian Islands: Fox Islands
21 Dec 1962 · 242 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.