Reviewed by USGSAlaska62y ago
M5.7 earthquake 259 km ESE of Attu Station, Alaska
Wednesday, February 17, 1965, 10:18:51 UTC · 51.688°N, 176.485°E
A magnitude 5.7 earthquake struck 259 km ESE of Attu Station, Alaska on Wednesday, February 17, 1965, 10:18:51 UTC, at a depth of 31.9 km (shallow). It is the strongest earthquake within 300 km since an M5.8 on February 15, 1965.
- Magnitude
- 5.7
- Moderate · mw
- Depth
- 32 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 earthquake
In context
How big was it, and why here?
Energy released
5 kilotons of TNT
That is about 1/3 of the Hiroshima bomb. It released about 10 times the energy of a magnitude 5.0.
Tectonic setting
79 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
32 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 75 km
USGS has not published any M2.5+ earthquake within 75 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 138 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.71965 Western Aleutian Islands (Hawadax/Rat Islands) EarthquakeFebruary 4, 1965 · 162 km E of this epicenter
- 8.31906 Western Aleutian Islands (Hawadax/Rat Islands) EarthquakeAugust 17, 1906 · 118 km E of this epicenter
- 7.4265 km WSW of Adak, AlaskaFebruary 4, 1965 · 217 km E of this epicenter
- 7.4151 km S of Attu Station, AlaskaSeptember 2, 1907 · 254 km W of this epicenter
- 7.2238 km SSE of Attu Station, AlaskaSeptember 8, 1939 · 131 km SW of this epicenter
- 7.2238 km WSW of Adak, AlaskaMarch 22, 1905 · 261 km E of this epicenter
- 7.0Rat Islands, Aleutian Islands, AlaskaFebruary 6, 1916 · 204 km SE of this epicenter
- 7.024 km E of Attu Station, AlaskaApril 16, 1940 · 238 km NW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 5 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1965M8.7
Aleutian Islands: Rat Islands
4 Feb 1965 · 162 km away · intensity VI
Under $1 million damagetsunami
- 1906M8.3
Aleutian Islands: Rat Islands
17 Aug 1906 · 118 km away
- 1909M7.8
Aleutian Islands
10 Apr 1909 · 108 km away
- 1965M7.6
Aleutian Islands: Rat Islands
30 Mar 1965 · 183 km away
tsunami
- 1940M7.4
Aleutian Islands: Rat Islands
14 Jul 1940 · 123 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.