Reviewed by USGSAlaska4y ago
M2.6 earthquake 45 km SE of False Pass, Alaska
Sunday, February 20, 2022, 08:42:08 UTC · 54.537°N, 162.977°W
A magnitude 2.6 earthquake struck 45 km SE of False Pass, Alaska on Sunday, February 20, 2022, 08:42:08 UTC, at a depth of 27.2 km (shallow).
- Magnitude
- 2.6
- Minor · ml
- Depth
- 27 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
120 kg of TNT
That is about 1/125,702 of the Hiroshima bomb. A magnitude 5.0 releases about 3,981 times more energy.
Tectonic setting
134 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: shallow
27 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 8 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M3.5 on March 9, 2022. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 2.941 km SSE of False Pass, Alaska4y ago · 19 km W of this epicenter
- 2.543 km SSE of False Pass, Alaska4y ago · 18 km W of this epicenter
- 2.943 km SSE of False Pass, Alaska4y ago · 18 km W of this epicenter
- 3.540 km SSE of False Pass, Alaska4y ago · 18 km W of this epicenter
- 2.738 km S of False Pass, Alaska4y ago · 23 km W of this epicenter
- 2.635 km S of False Pass, Alaska4y ago · 31 km W of this epicenter
- 2.623 km SSE of False Pass, Alaska4y ago · 26 km NW of this epicenter
- 2.652 km SE of False Pass, Alaska4y ago · 7 km SE of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 388 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 · 117 km S of this epicenter
- 7.82020 Perryville, Alaska EarthquakeJuly 22, 2020 · 287 km E of this epicenter
- 7.62020 Sand Point, Alaska EarthquakeOctober 19, 2020 · 216 km E of this epicenter
- 7.454 km SE of Sand Point, AlaskaMay 31, 1917 · 205 km E of this epicenter
- 7.190 km SE of King Cove, AlaskaMay 14, 1948 · 117 km E of this epicenter
- 7.139 km S of Akutan, AlaskaMarch 22, 1957 · 201 km SW of this epicenter
- 7.071 km SE of King Cove, AlaskaMay 30, 1991 · 88 km E of this epicenter
- 6.917 km S of Sand Point, AlaskaMay 13, 1993 · 176 km NE 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 · 117 km away · intensity VI
168 deaths$26 million damagetsunami
- 2020M7.8
Alaska
22 Jul 2020 · 287 km away · intensity VII
Limited damage (under $1M)tsunami
- 1788M8.0
Alaska Peninsula
6 Aug 1788 · 137 km away
tsunami
- 2020M7.6
Alaska
19 Oct 2020 · 216 km away · intensity IX
tsunami
- 1948M7.5
Alaska Peninsula
14 May 1948 · 128 km away
- 1957M7.5
Aleutian Islands: Fox Islands
22 Mar 1957 · 152 km away · intensity V
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.