QuakeScout
Magnitude6.0

Reviewed by USGSAlaska70y ago

M6.0 earthquake 164 km WSW of Nikolski, Alaska

Monday, March 18, 1957, 02:25:34 UTC · 52.362°N, 171.106°W

A magnitude 6.0 earthquake struck 164 km WSW of Nikolski, Alaska on Monday, March 18, 1957, 02:25:34 UTC, at a depth of 38.6 km (shallow). It is the strongest earthquake within 300 km since an M6.4 on March 15, 1957.

Magnitude
6.0
Moderate · mw
Depth
39 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

13 kilotons of TNT

That is about the energy of the Hiroshima bomb. It released about 28 times the energy of a magnitude 5.0.

Tectonic setting

116 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

39 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 lists 1 M2.5+ earthquake within 75 km in the following 30 days. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M5M61h6h1d3d7d14d30dMainshock M6.0
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.

    Regional history

    Past M5+ earthquakes within 300 km

    USGS lists 87 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:

    1. 7.8234 km SSW of Nikolski, AlaskaMarch 7, 1929 · 186 km SE of this epicenter
    2. 7.4133 km WNW of Nikolski, AlaskaApril 18, 1916 · 124 km N of this epicenter
    3. 7.135 km SW of Nikolski, AlaskaMarch 11, 1957 · 135 km E of this epicenter
    4. 6.980 km SW of Nikolski, AlaskaMarch 9, 1957 · 106 km E of this epicenter
    5. 6.9182 km SSE of Atka, AlaskaJanuary 27, 1906 · 208 km SW of this epicenter
    6. 6.977 km SSW of Nikolski, AlaskaJanuary 23, 1935 · 114 km E of this epicenter

    History · NOAA

    Deadliest earthquakes in this area

    NOAA’s significant-earthquake database lists 8 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:

    1. 1901M7.8

      Aleutian Islands: Fox Islands

      31 Dec 1901 · 102 km away

      Limited damage (under $1M)tsunami

    2. 1917M7.9

      Alaska Peninsula

      31 May 1917 · 300 km away · intensity V

    3. 1902M7.8

      Aleutian Islands: Fox Islands

      1 Jan 1902 · 245 km away

    4. 1907M7.8

      Aleutian Islands

      2 Sep 1907 · 97 km away

    5. 1929M7.8

      Aleutian Islands: Fox Islands

      7 Mar 1929 · 170 km away · intensity V

      tsunami

    6. 1916M7.5

      Aleutian Islands: Fox Islands

      18 Apr 1916 · 128 km away

    NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.

    Nearby trackers

    Closest city pages