Near Cameron in Madison County, Montana — The American West (Mountains)
On August 17, 1959, a magnitude 7.3 earthquake struck Hebgen Lake about 12 miles northeast of here. The earthquake ruptured two faults, the Hebgen Lake fault and the Red Canyon fault, and caused parts of the Hebgen Lake basin to subside as much as 22 feet. The sudden tilting of Hebgen Lake caused a large wave - a seiche - to wash back and forth across the lake overtopping Hebgen Dam and sweeping shoreline cabins off their foundations. It also shook loose a mountainside - the 37 million cubic yard Madison Canyon landslide - that dammed the Madison River to form Earthquake Lake. The landslide buried part of a campground, killing 26 people.
• Montana is one of the more seismically active states in the United States. An average of five earthquakes occur every day. Most are to tiny that a sensitive seismograph is needed to detect them.
• The Hebgen Lake earthquake was felt over an area of 600,00 square miles including all of Montana and from Banff, Canada to Provo, Utah, and from western North Dakota to Seattle, Washington.
• Earthquake strength is measured using the Richter scale, which measures the seismic energy released by a quake and by the Mercalli
• Movement along the Hebgen Lake and Red Canyon faults offer the land surface to form a fault scarp that runs like a scar along the north side of Hebgen Lake. Look for this fault scarps at the base of the mountains as you drive east along the Hebgen Lake.
Erected by Montana Department of Transportation.
Topics. This historical marker is listed in these topic lists: Disasters • Natural Features. A significant historical date for this entry is August 17, 1959.
Location. 44° 54.125′ N, 111° 35.594′ W. Marker is near Cameron, Montana, in Madison County. Marker is on Forest Road 209 near U.S. 287. Touch for map. Marker is in this post office area: Cameron MT 59720, United States of America. Touch for directions.
Other nearby markers. At least 4 other markers are within 11 miles of this marker, measured as the crow flies. A Tough Business (a few steps from this marker); Motoring Through Paradise: The Vigilante Trail (a few steps from this marker); Raynolds' Pass (approx. 8 miles away); The Seismic Shake that Shaped this Lake (approx. 10.3 miles away).
More about this marker. This marker is located at the Raynolds Pass Rest Area.
Also see . . . This massive Yellowstone earthquake... -- Timeline. ... “The lake seems eerie, what with its bone-white ghost trees, which were killed by the post-quake flooding.” Those trees still rise from the basin of the lake, and the site is replete with reminders of that disastrous night nearly 60 years ago, including mangled wood buildings along the shoreline, and swaths of earthen mountainside conspicuously bereft of pine and vegetation. (Submitted on October 23, 2019, by Barry Swackhamer of Brentwood, California.)
Credits. This page was last revised on October 23, 2019. It was originally submitted on October 23, 2019, by Barry Swackhamer of Brentwood, California. This page has been viewed 148 times since then and 38 times this year. Photos: 1, 2, 3. submitted on October 23, 2019, by Barry Swackhamer of Brentwood, California.