1945 – Flathead Lake, MT – M 5.5

Intermountain Seismic Belt Historical Earthquake Project

September 23, 1945 – Flathead Lake, MT – M 5.5

At 2:57 a.m. on Sunday, September 23, 1945, a magnitude 5.5 earthquake occurred near Lakeside, Montana on the northwest side of Flathead Lake.

The earthquake was reported felt in western Montana, northern Idaho and eastern Washington. There were reports of dishes and windows rattling from Helena, Montana to Walla Walla, Washington. In Kalispell, Montana the shaking awakened most people. Many reported their homes creaking. No significant damage or injuries were reported.



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ISB Hist EQ Proj

1952 – Bigfork, MT – M 5.5

Intermountain Seismic Belt Historical Earthquake Project

March 31, 1952 – Bigfork, MT – M 5.5

A magnitude 5.5 earthquake occurred in Montana at 5:37 p.m. on Monday, March 31, 1952. The epicenter was located approximately 15 miles east of Bigfork, Montana—a town on the northeast shore of Flathead Lake, Montana.

Reports from some individuals on the east shore of Flathead Lake noted that pictures swung on the wall and wood in houses creaked. In Kalispell, Montana (approximately 23 miles northwest of Bigfork) it was reported that houses shook, kitchen doors rattled and tables moved.

No injuries or significant damage from this earthquake was reported.



For additional information about this earthquake:

Earthquake Summary 3D Newspaper Articles 3D Additional Resources 3D Blank Thumbnail

For more information about this project:

ISB Hist EQ Proj