The April 17, 1916 earthquake

M7.4near Nikolski, Alaska

A magnitude 7.4 earthquake 87.0 miles deep, 43.2 miles off Aleutians West Census Area. The 22nd strongest in Alaska’s record since 1900, and the strongest within 50 miles in the catalogue, which runs from 1900.

The earthquake

Magnitude: 7.4; body-wave magnitude (mB)
Depth: 87.0 mi; 140.0 km below the surface
Local time: Monday, April 17, 1916; 17:01 NST; 04:01 UTC on Apr 18, 1916
Epicentre: 53.44°N, 170.67°W; 43.2 mi from Aleutians West Census Area
In Alaska’s record: 22nd; strongest of 124,625 since 1900
Within 50 miles: 1; county; more on this date

USGS ANSS Comprehensive Earthquake Catalog, event iscgemsup913789 (“133 km WNW 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 · 43.2 mi

Earthquakes around the epicentre

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

No earlier earthquake of magnitude 5 or more within 50 miles in the catalogue since 1900.

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