Reviewed by USGSAlaska4y ago
M3.7 earthquake 68 km SSE of Akutan, Alaska
Wednesday, September 7, 2022, 22:24:11 UTC · 53.545°N, 165.464°W
A magnitude 3.7 earthquake struck 68 km SSE of Akutan, Alaska on Wednesday, September 7, 2022, 22:24:11 UTC, at a depth of 45.7 km (shallow).
- Magnitude
- 3.7
- Minor · mb
- Depth
- 46 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- I
- Not felt (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
5 tons of TNT
That is about 1/2,814 of the Hiroshima bomb. A magnitude 5.0 releases about 89 times more energy.
Tectonic setting
94 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
46 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 M3.6 on September 8, 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 577 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 · 174 km E of this epicenter
- 7.881 km E of Nikolski, AlaskaJuly 2, 1965 · 157 km W of this epicenter
- 7.139 km S of Akutan, AlaskaMarch 22, 1957 · 33 km NW of this epicenter
- 7.135 km SW of Nikolski, AlaskaMarch 11, 1957 · 266 km W of this epicenter
- 7.071 km SE of King Cove, AlaskaMay 30, 1991 · 276 km NE of this epicenter
- 7.0203 km SSE of Unalaska, AlaskaAugust 22, 1940 · 154 km S of this epicenter
- 6.977 km SSW of Nikolski, AlaskaJanuary 23, 1935 · 297 km SW 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 · 174 km away · intensity VI
168 deaths$26 million damagetsunami
- 1965M6.5
Aleutian Islands: Fox Islands
2 Jul 1965 · 150 km away
Limited damage (under $1M)tsunami
- 1917M7.9
Alaska Peninsula
31 May 1917 · 275 km away · intensity V
- 1902M7.8
Aleutian Islands: Fox Islands
1 Jan 1902 · 186 km away
- 1957M7.5
Aleutian Islands: Fox Islands
22 Mar 1957 · 163 km away · intensity V
- 2015M6.9
Alaska
27 Jul 2015 · 297 km away · intensity IV
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.