Reviewed by USGSAlaska4y ago
M2.7 earthquake 223 km SSW of Akhiok, Alaska
Friday, April 1, 2022, 12:18:00 UTC · 55.093°N, 155.553°W
A magnitude 2.7 earthquake struck 223 km SSW of Akhiok, Alaska on Friday, April 1, 2022, 12:18:00 UTC, at a depth of 0.4 km (shallow).
- Magnitude
- 2.7
- Minor · ml
- Depth
- 0 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
40 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
0 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 2 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M2.6 on April 22, 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 337 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.21938 Semidi Islands, Alaska EarthquakeNovember 10, 1938 · 167 km W of this epicenter
- 8.22021 Chignik, Alaska EarthquakeJuly 29, 2021 · 151 km W of this epicenter
- 7.82020 Perryville, Alaska EarthquakeJuly 22, 2020 · 194 km W of this epicenter
- 7.62020 Sand Point, Alaska EarthquakeOctober 19, 2020 · 266 km W of this epicenter
- 7.454 km SE of Sand Point, AlaskaMay 31, 1917 · 276 km W of this epicenter
- 7.14 km ENE of Karluk, AlaskaNovember 7, 1912 · 287 km N of this epicenter
- 7.0113 km ESE of Chignik, AlaskaMay 4, 1923 · 113 km NW of this epicenter
- 7.026 km SSE of Karluk, AlaskaDecember 6, 1999 · 261 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 11 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1900M8.3
Kodiak Island
9 Oct 1900 · 257 km away · intensity VIII
Limited damage (under $1M)
- 1788M8.0
Unga Island
21 Jul 1788 · 265 km away · intensity VII
Limited damage (under $1M)tsunami
- 2020M7.8
Alaska
22 Jul 2020 · 194 km away · intensity VII
Limited damage (under $1M)tsunami
- 1970M6.0
Andreanof Islands
11 Mar 1970 · 286 km away · intensity V
Limited damage (under $1M)tsunami
- 1938M8.2
Alaska
10 Nov 1938 · 183 km away · intensity VI
tsunami
- 2021M8.2
Alaska Peninsula
29 Jul 2021 · 147 km away · intensity VIII
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.