The March 21, 1905 earthquake

M7.2near Adak, Alaska

A magnitude 7.2 earthquake 21.7 miles deep, 32.0 miles off Aleutians West Census Area. The 34th strongest in Alaska’s record since 1900, and the strongest within 50 miles in the catalogue, which runs from 1900.

The earthquake

Magnitude: 7.2; moment magnitude (mw)
Depth: 21.7 mi; 35.0 km below the surface
Local time: Tuesday, March 21, 1905; 16:38 NST; 03:38 UTC on Mar 22, 1905
Epicentre: 51.15°N, 179.86°W; 32.0 mi from Aleutians West Census Area
In Alaska’s record: 34th; strongest of 124,625 since 1900
Within 50 miles: 1; county; more on this date

USGS ANSS Comprehensive Earthquake Catalog, event iscgem16957847 (“238 km WSW of Adak, 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 · 32.0 mi

Earthquakes around the epicentre

2,794 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.