Reviewed by USGSAlaska4y ago
M3.1 earthquake 106 km SE of Akutan, Alaska
Tuesday, June 21, 2022, 12:32:15 UTC · 53.549°N, 164.486°W
A magnitude 3.1 earthquake struck 106 km SE of Akutan, Alaska on Tuesday, June 21, 2022, 12:32:15 UTC, at a depth of 35.0 km (shallow).
- Magnitude
- 3.1
- 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
674 kg of TNT
That is about 1/22,353 of the Hiroshima bomb. A magnitude 5.0 releases about 708 times more energy.
Tectonic setting
71 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 4 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M3.3 on July 7, 2022. 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 488 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 · 110 km E of this epicenter
- 7.881 km E of Nikolski, AlaskaJuly 2, 1965 · 219 km W of this epicenter
- 7.190 km SE of King Cove, AlaskaMay 14, 1948 · 246 km NE of this epicenter
- 7.139 km S of Akutan, AlaskaMarch 22, 1957 · 88 km W of this epicenter
- 7.071 km SE of King Cove, AlaskaMay 30, 1991 · 219 km NE of this epicenter
- 7.0203 km SSE of Unalaska, AlaskaAugust 22, 1940 · 169 km SW of this epicenter
- 6.980 km E of Nikolski, AlaskaMarch 24, 1980 · 221 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 10 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 · 110 km away · intensity VI
168 deaths$26 million damagetsunami
- 1965M6.5
Aleutian Islands: Fox Islands
2 Jul 1965 · 212 km away
Limited damage (under $1M)tsunami
- 1788M8.0
Alaska Peninsula
6 Aug 1788 · 278 km away
tsunami
- 1902M7.8
Aleutian Islands: Fox Islands
1 Jan 1902 · 239 km away
- 1948M7.5
Alaska Peninsula
14 May 1948 · 251 km away
- 1957M7.5
Aleutian Islands: Fox Islands
22 Mar 1957 · 168 km away · intensity V
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.