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Historic Earthquakes

Southwest Montana
1947 11 23 09:46 UTC
Magnitude 6.3
Intensity VIII

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.