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Pictures -Idaho Mountains
A) The view from Pioneer Cabin, above Sun Valley, of the cirques at the head of Hyndman Creek, Pioneer Mountains, (July, 1987). The rugged cirques are carved from Proterozoic and Paleozoic metamorphic rocks as well as Eocene granite. Pioneer Cabin was built as a ski base cabin in the 1930s during early development of the Sun Valley resort .
C) Folded sedimentary rocks in the high Boulder Mountains, north of Ketchum, looking south to the Pioneer Mountains. The peaks on the skyline, in the Pioneer metamorphic core, are made of metamorphic and igneous rock, some as old as 2300 million years, (July, 1987).
B) The north face of the Devil's Bedstead, the most prominent peak of the northern Pioneer Mountains (11,865 feet high). The Bedstead can be seen from a large area to the east and north in the Lost River Valley. View looks south up the valley of Kane Creek from the Summit Creek road. The Bedstead is made of Eocene intrusive rock. The Wildhorse detachment fault, separating lower from upper plates of the Pioneer Mountains metamorphic core complex, is in the saddle immediately east (left) of the Bedstead. In the shadows in the foreground along Kane Creek are humpy mounds made of moraines formed by the Kane Creek glacier during the Potholes glaciation (about 20,000 years ago). These lie on flat river terraces formed during the earlier Copper Basin (bull Lake) glaciation, (July,1993).
D) View of the Silent City of Rocks, southern Albion Range, southwest of Almo, looking northeast from the summit of Bath Rock, (September, 1992). The Oligocene City of Rocks lobe of the Almo Pluton forms the exfoliating and jointed terrane in the foreground. The Archean Green Creek Complex underlies the darker colored ridges on the skyline.