Reviewed by USGSAlaska70y ago
M5.8 earthquake 150 km SSE of Atka, Alaska
Tuesday, April 2, 1957, 21:27:59 UTC · 51.035°N, 173.093°W
A magnitude 5.8 earthquake struck 150 km SSE of Atka, Alaska on Tuesday, April 2, 1957, 21:27:59 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M5.8 on April 2, 1957.
- Magnitude
- 5.8
- Moderate · mw
- Depth
- 15 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
8 kilotons of TNT
That is about 1/2 of the Hiroshima bomb. It released about 16 times the energy of a magnitude 5.0.
Tectonic setting
5 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
15 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 89 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.61957 Atka, Alaska EarthquakeMarch 9, 1957 · 184 km W of this epicenter
- 7.8234 km SSW of Nikolski, AlaskaMarch 7, 1929 · 232 km E of this epicenter
- 7.65 km WNW of Adak, AlaskaFebruary 14, 1905 · 267 km W of this epicenter
- 7.175 km S of Adak, AlaskaMarch 14, 1957 · 255 km W of this epicenter
- 7.160 km SW of Adak, AlaskaMarch 12, 1957 · 293 km W of this epicenter
- 7.0101 km S of Adak, AlaskaSeptember 9, 1910 · 228 km W 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, which together caused about 2 recorded deaths. The most severe:
- 1957M8.6
Alaska
9 Mar 1957 · 184 km away
2 deathsSevere damage ($5–24M)tsunami
- 1901M7.8
Aleutian Islands: Fox Islands
31 Dec 1901 · 151 km away
Limited damage (under $1M)tsunami
- 1907M7.8
Aleutian Islands
2 Sep 1907 · 289 km away
- 1929M7.8
Aleutian Islands: Fox Islands
7 Mar 1929 · 216 km away · intensity V
tsunami
- 1946
East Aleutian Islands
1 Nov 1946 · 111 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.