The February 13, 1951 earthquake

M6.9near Chignik, Alaska

A magnitude 6.9 earthquake 12.4 miles deep, 20.2 miles off Kodiak Island Borough. The 72nd strongest in Alaska’s record since 1900, and the strongest within 50 miles since a magnitude 7.0 on May 4, 1923.

The earthquake

Magnitude: 6.9; moment magnitude (mw)
Depth: 12.4 mi; 20.0 km below the surface
Local time: Tuesday, February 13, 1951; 12:13 AST; 22:13 UTC
Epicentre: 55.80°N, 156.28°W; 20.2 mi from Kodiak Island Borough
In Alaska’s record: 72nd; strongest of 124,625 since 1900
Within 50 miles: 1; county; more on this date

USGS ANSS Comprehensive Earthquake Catalog, event iscgem894107 (“143 km ESE of Chignik, Alaska”). The USGS event page carries the ShakeMap, felt reports and the official summary.

Counties and cities within 50 miles

Distance from the epicentre to each county boundary (zero when inside) and to each city centre.

Counties

Kodiak Island BoroughAK · 20.2 mi

Earthquakes around the epicentre

467 earthquakes of magnitude 3 or more within 50 miles of this epicentre since 1973.

Earlier earthquakes of magnitude 5 or more within 50 miles, strongest first

May 4, 1923M7.0
July 28, 1934M6.6
November 10, 1944M6.2
March 16, 1940M6.1
September 12, 1911M6.1
November 15, 1938M6.0

USGS ANSS Comprehensive Earthquake Catalog. Local time is the time zone of the county nearest the epicentre. Magnitudes are as the catalogue reports them.