The August 3, 1960 earthquake

M6.5Rat Islands, Aleutian Islands, Alaska

A magnitude 6.5 earthquake 11.6 miles deep, 9.9 miles off Aleutians West Census Area. The 182nd strongest in Alaska’s record since 1900, and the strongest within 50 miles since a magnitude 6.6 on October 28, 1958.

The earthquake

Magnitude: 6.5; moment magnitude (mw)
Depth: 11.6 mi; 18.6 km below the surface
Local time: Wednesday, August 3, 1960; 20:34 NST; 07:34 UTC on Aug 4, 1960
Epicentre: 51.36°N, 178.88°E; 9.9 mi from Aleutians West Census Area
In Alaska’s record: 182nd; strongest of 124,625 since 1900
Within 50 miles: 1; county; more on this date

USGS ANSS Comprehensive Earthquake Catalog, event iscgem879987 (“Rat Islands, Aleutian Islands, 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

Aleutians West Census AreaAK · 9.9 mi

Earthquakes around the epicentre

3,025 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

August 16, 1906M8.3
February 6, 1916M7.0
April 26, 1930M6.7
March 27, 1940M6.6
October 28, 1958M6.6
May 20, 1930M6.5
February 2, 1930M6.5
September 14, 1924M6.4
July 14, 1919M6.2
June 1, 1955M6.1

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