irregularly shaped boulders cemented together by ice, which is not 

 evident on the surface but facilitates slow movement of the entire 

 rock mass. The rocks are broken off the surrounding valley walls 

 through freezing and thawing. When one of Big Sky's chairlifts 

 was designed, special consideration was given to placing the 

 supporting towers on stable ground rather than the moving ice and 

 rocks . 



In the headwaters of Hyalite Creek south of Bozeman one finds 

 the greatest density of named waterfalls in the state outside 

 Montana's national parks and wilderness areas. Ten waterfalls can 

 be found within about 12 square miles, and a system of Forest 

 Service hiking trails provides access to most of them. The area 

 remains undisturbed for the most part. Palisade Falls, the most 

 accessible of these falls, tumbles over a basalt cliff noted for 

 its columnar jointing and straight drop. This basalt cliff 

 originated as a flow of molten rock, which cooled and contracted. 

 Vertical cracks were formed in the rock. The resulting rock 

 columns, visible in the steep cliff, are hexagonal or pentagonal 

 in cross sections. 



Farther to the south is Quake Lake. The August 1959 

 earthquake in the Madison River Valley west of Hebgen Lake caused 

 a large rock avalanche to dam the river and impound the lake. 

 Though modified somewhat from its original state by the Army Corps 

 of Engineers and Montana Department of Highways, the Quake Lake 

 slide remains an excellent example of a massive avalanche and 

 landslide associated with the earthquake. The Forest Service 

 visitor center just off U.S. Highway 287 provides an excellent 

 viewpoint to observe these features. 



The Cedar Creek alluvial fan in the Madison Valley southeast 

 of Ennis is a textbook example of an alluvial fan. It is 18 square 

 miles in area and can easily be seen on the Ennis 15-minute United 

 States Geological Survey topographic map. This feature was formed 

 when Cedar Creek, a high gradient tributary stream, enters the 

 relatively flat intermountain valley containing the Madison River. 

 Because of the abrupt change in gradient. Cedar Creek is no longer 

 able to transport its heavy load of sediment and the sediment is 

 deposited at the edge of the valley in a fan shape. 



In the headwaters of Pipestone Creek between Whitehall and 

 Butte, several outstanding features are found. Spherical 

 weathering of the granite along the north side of Interstate 90 

 has resulted in an array of tall, smooth boulders standing on the 

 open hillsides. Fossil beds are found in the lower elevations of 

 this area on private lands. Badlands near Pipestone have yielded 

 vertebrate fossils from sedimentary deposits of Oligocene and 

 Miocene age. 



The Ringing Rocks, an assemblage of dark, irregularly shaped 

 boulders that have weathered from a stock, are found on Bureau of 

 Land Management land north of Pipestone. When struck with a 



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