Reviewed by USGSAlaska4y ago
M3.3 earthquake 33 km NNE of King Cove, Alaska
Thursday, January 20, 2022, 17:05:41 UTC · 55.347°N, 162.131°W
A magnitude 3.3 earthquake struck 33 km NNE of King Cove, Alaska on Thursday, January 20, 2022, 17:05:41 UTC, at a depth of 137.4 km (intermediate).
- Magnitude
- 3.3
- Minor · ml
- Depth
- 137 km
- Intermediate
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquake
In context
How big was it, and why here?
Energy released
1 tons of TNT
That is about 1/11,203 of the Hiroshima bomb. A magnitude 5.0 releases about 355 times more energy.
Tectonic setting
205 km
from the nearest mapped plate boundary, between the North American and Pacific plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: intermediate
137 km
Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.
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 has not published any M2.5+ earthquake within 50 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 376 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 · 211 km S of this epicenter
- 8.21938 Semidi Islands, Alaska EarthquakeNovember 10, 1938 · 251 km E of this epicenter
- 8.22021 Chignik, Alaska EarthquakeJuly 29, 2021 · 268 km E of this epicenter
- 7.82020 Perryville, Alaska EarthquakeJuly 22, 2020 · 226 km E of this epicenter
- 7.62020 Sand Point, Alaska EarthquakeOctober 19, 2020 · 180 km SE of this epicenter
- 7.454 km SE of Sand Point, AlaskaMay 31, 1917 · 148 km E of this epicenter
- 7.190 km SE of King Cove, AlaskaMay 14, 1948 · 104 km SE of this epicenter
- 7.139 km S of Akutan, AlaskaMarch 22, 1957 · 292 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 · 211 km away · intensity VI
168 deaths$26 million damagetsunami
- 2020M7.8
Alaska
22 Jul 2020 · 226 km away · intensity VII
Limited damage (under $1M)tsunami
- 1938M8.2
Alaska
10 Nov 1938 · 238 km away · intensity VI
tsunami
- 2021M8.2
Alaska Peninsula
29 Jul 2021 · 271 km away · intensity VIII
tsunami
- 1788M8.0
Alaska Peninsula
6 Aug 1788 · 82 km away
tsunami
- 2020M7.6
Alaska
19 Oct 2020 · 180 km away · intensity IX
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.