Reviewed by USGSAlaska4y ago
M2.7 earthquake 86 km S of False Pass, Alaska
Friday, January 21, 2022, 13:57:26 UTC · 54.084°N, 163.222°W
A magnitude 2.7 earthquake struck 86 km S of False Pass, Alaska on Friday, January 21, 2022, 13:57:26 UTC, at a depth of 23.9 km (shallow).
- Magnitude
- 2.7
- Minor · ml
- Depth
- 24 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
169 kg of TNT
That is about 1/88,990 of the Hiroshima bomb. A magnitude 5.0 releases about 2,818 times more energy.
Tectonic setting
93 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
24 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 10 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M3.8 on January 25, 2022. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 2.652 km SE of False Pass, Alaska4y ago · 49 km NE of this epicenter
- 2.941 km SSE of False Pass, Alaska4y ago · 45 km N of this epicenter
- 3.038 km SSE of False Pass, Alaska4y ago · 48 km N of this epicenter
- 3.7101 km S of False Pass, Alaska4y ago · 23 km SW of this epicenter
- 2.743 km SSE of False Pass, Alaska4y ago · 43 km N of this epicenter
- 3.841 km SSE of False Pass, Alaska4y ago · 45 km N of this epicenter
- 2.643 km SSE of False Pass, Alaska4y ago · 43 km N of this epicenter
- 2.938 km SSE of False Pass, Alaska4y ago · 49 km N of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 425 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 · 71 km S of this epicenter
- 7.62020 Sand Point, Alaska EarthquakeOctober 19, 2020 · 240 km E of this epicenter
- 7.454 km SE of Sand Point, AlaskaMay 31, 1917 · 238 km NE of this epicenter
- 7.190 km SE of King Cove, AlaskaMay 14, 1948 · 145 km NE of this epicenter
- 7.139 km S of Akutan, AlaskaMarch 22, 1957 · 170 km W of this epicenter
- 7.071 km SE of King Cove, AlaskaMay 30, 1991 · 118 km NE of this epicenter
- 7.0203 km SSE of Unalaska, AlaskaAugust 22, 1940 · 263 km SW of this epicenter
- 6.917 km S of Sand Point, AlaskaMay 13, 1993 · 215 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 8 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 · 71 km away · intensity VI
168 deaths$26 million damagetsunami
- 1788M8.0
Alaska Peninsula
6 Aug 1788 · 176 km away
tsunami
- 2020M7.6
Alaska
19 Oct 2020 · 240 km away · intensity IX
tsunami
- 1948M7.5
Alaska Peninsula
14 May 1948 · 151 km away
- 1957M7.5
Aleutian Islands: Fox Islands
22 Mar 1957 · 163 km away · intensity V
- 1820
East Aleutian Islands
1 Mar 1820 · 105 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.