Historic Earthquakes

Borah Peak, Idaho
1983 October 28 14:06:06 UTC
Magnitude 6.9

Largest Earthquake in Idaho

Isoseismal Map

Isoseismals are based on intensity estimates from data.

Isoseismal Map

Abridged from Seismicity of the United States, 1568-1989 (Revised), by Carl W. Stover and Jerry L. Coffman, U.S. Geological Survey Professional Paper 1527, United States Government Printing Office, Washington: 1993.