Near Polaris in Beaverhead County, Montana — The American West (Mountains)
The Way It Used To Be... Way Back
The Way It Used To Be... Way Back
We proceeded down Willards Creek on the S.W. Side about 11 miles...The Country through which we passed to day was diversified high dry and uneaven Stoney open plains and low bottoms very boggy with high mountains on the tops and North sides of which there was Snow, great quantities of the Species of hyssop (sagebrush) & shrubs common the Missouri Plains are scattered in this Valleys and hill sides. The road which we have traveled from travellers rest Creek to this place an excellent road. ...Shields killed an antelope. -- William Clark, July 8, 1806
The elevation here is about 6,100 feet (1,859 m above sea level). The granite peak of Baldy Mountain to the northeast - Sacajawea's landmark for the route of the expedition in this area - is 10,568 ft (3,221 m). The native plants and animals of 200 years ago can still be seen here. The July nights are still "remarkably Cold," as Clark described them. Little has changed since the time of Sacajawea's ancestors - who came to this place long before she guided the Corps of Discovery and William Clark
How different Clark's journal entries might have been at that time! 47 million years ago, there were no Pioneer Mountains. This was the edge of the Renova Basin, draining to the east. No snow, no sagebrush, no antelope. Fossils show the climate was tropical.
The Pioneer Mountains started rising about four million years ago - and they are still rising. About 17 million years ago, the earth's crust in this region began to extend, or stretch. It is becoming thinner and more flexible, allowing the super-hot molten magma of the aesthenosphere (sic) to bulge upward. This causes blocks of crust to move up or down along faults, which are like cracks in the earth's crust.
The crust in this region has broken along northwest-trending normal faults, and the rising blocks are building the Pioneer Mountains, while adjoining blocks have dropped down, deepening the valleys.
As blocks of the earth's crust move
Erected by USDA Forest Service, University of Montana - Western.
Marker series. This marker is included in the Lewis & Clark Expedition marker series.
Location. 45° 16.872′ N, 113° 7.338′ W. Marker is near Polaris, Montana, in Beaverhead County. Marker is on Pioneer Mountains National Forest Scenic Bywayt (Forest Road 73) near State Highway 278, on the right when traveling north. Touch for map. Marker is in this post office area: Polaris MT 59746, United States of America.
Other nearby markers. At least 8 other markers are within 10 miles of this marker, measured as the crow flies. "I now take my leave..." (approx. 6˝ miles away); Welcome to Hamilton Ranch (approx. 6.8 miles away); "Hot Spring Valley" (approx. 6.8 miles away); A Soul-Searching Birthday (approx. 6.8 miles away); "The Carroll Ranch" (approx. 6.8 miles away); Naturally Sustained Productivity (approx. 6.8 miles away); Undaunted Stewardship (approx. 6.9 miles away); The First Electric Gold Dredge (approx. 9.7 miles away).
Also see . . . Tours - Pioneer Mountains Scenic Byway - U.S. Forest Service. The Pioneer Mountains Scenic Byway, designated in 1989, cuts through the middle of the Pioneer Mountains in Southwest Montana's Beaverhead County. The route goes from the town of Wise River, south along the stream of the same name, and then crosses into the historic valley formed by Grasshopper Creek. (Submitted on October 5, 2018, by Barry Swackhamer of San Jose, California.)
Categories. • Environment • Exploration • Natural Features • Roads & Vehicles •
Credits. This page was last revised on October 5, 2018. This page originally submitted on October 5, 2018, by Barry Swackhamer of San Jose, California. This page has been viewed 49 times since then and 4 times this year. Photos: 1, 2, 3. submitted on October 5, 2018, by Barry Swackhamer of San Jose, California.