Piegan Mountain
Piegan Mountain is located in the Lewis Range, Glacier National Park in the U.S. state of Montana. Piegan Glacier is located in a cirque immediately southeast of the summit.Geology
Like other mountains in Glacier National Park, Piegan Mountain is composed of sedimentary rock laid down during the Precambrian to Jurassic periods. Formed in shallow seas, this sedimentary rock was initially uplifted beginning 170 million years ago when the Lewis Overthrust fault pushed an enormous slab of precambrian rocks thick, wide and long over younger rock of the cretaceous period.
