Reviewed by USGS48y ago
M4.4 earthquake south of Alaska
Wednesday, February 14, 1979, 04:50:37 UTC · 55.441°N, 156.891°W
A magnitude 4.4 earthquake struck south of Alaska on Wednesday, February 14, 1979, 04:50:37 UTC, at a depth of 33.0 km (shallow).
- Magnitude
- 4.4
- Light · mb
- Depth
- 33 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
60 tons of TNT
That is about 1/251 of the Hiroshima bomb. A magnitude 5.0 releases about 8 times more energy.
Tectonic setting
111 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
33 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 1 M2.5+ earthquake within 50 km in the following 30 days; the largest was M4.5 on February 17, 1979. 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 148 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 · 87 km W of this epicenter
- 7.454 km SE of Sand Point, AlaskaMay 31, 1917 · 196 km W of this epicenter
- 7.190 km SE of King Cove, AlaskaMay 14, 1948 · 288 km W of this epicenter
- 7.14 km ENE of Karluk, AlaskaNovember 7, 1912 · 284 km NE of this epicenter
- 7.0113 km ESE of Chignik, AlaskaMay 4, 1923 · 45 km N of this epicenter
- 6.9105 km ESE of Perryville, AlaskaNovember 17, 1938 · 53 km W of this epicenter
- 6.9143 km ESE of Chignik, AlaskaFebruary 13, 1951 · 56 km NE of this epicenter
- 6.9171 km SW of Akhiok, AlaskaFebruary 6, 1964 · 73 km NE 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. The most severe:
- 1900M8.3
Kodiak Island
9 Oct 1900 · 279 km away · intensity VIII
Limited damage (under $1M)
- 1788M8.0
Unga Island
21 Jul 1788 · 296 km away · intensity VII
Limited damage (under $1M)tsunami
- 1970M6.0
Andreanof Islands
11 Mar 1970 · 293 km away · intensity V
Limited damage (under $1M)tsunami
- 1938M8.2
Alaska
10 Nov 1938 · 93 km away · intensity VI
tsunami
- 1788M8.0
Alaska Peninsula
6 Aug 1788 · 265 km away
tsunami
- 1906M7.6
Aleutian Islands
23 Dec 1906 · 243 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.