The July 22, 1933 earthquake

M6.8near Nikolski, Alaska

A magnitude 6.8 earthquake 18.6 miles deep, 12.0 miles off Aleutians West Census Area. The 114th strongest in Alaska’s record since 1900, and the strongest within 50 miles in the catalogue, which runs from 1900.

The earthquake

Magnitude: 6.8; moment magnitude (mw)
Depth: 18.6 mi; 30.0 km below the surface
Local time: Saturday, July 22, 1933; 10:55 AST; 20:55 UTC
Epicentre: 52.59°N, 169.23°W; 12.0 mi from Aleutians West Census Area
In Alaska’s record: 114th; strongest of 124,625 since 1900
Within 50 miles: 1; county; more on this date

USGS ANSS Comprehensive Earthquake Catalog, event iscgem905732 (“46 km SSW of Nikolski, 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 · 12.0 mi

Earthquakes around the epicentre

3,149 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 11, 1932M6.5
January 11, 1907M6.3
August 26, 1920M6.2
March 10, 1929M5.7
August 10, 1932M5.7
March 29, 1931M5.7

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