U. S. GEOLOOICAL SURVKY 



BULLETIN 707 I'LATE XXIV 



A. PIKES PEAK AND THE ROCKY MOUNTAIN PENEPLAIN. 



The appearance of Pikes Peak depends largely upon the point of view and the selliiiK. From 

 Colorado Sprinfrs it seems to be a mass of mountains piled one above another until it culmi- 

 nates in the main peak. Viewed from ihe north, as in tliis picture, it is clearly a single moun- 

 tain mass standing on a plain (Rocky Mountain peneplain) left by the erosion of the surround- 

 ing rocks. The plain has an elevation of about 9,200 feet, and this peak rises nearly 1,800 

 feet above it. Photograph by G. B. Richardson. 



B. UTE PASS. 



This view is taken from a point near the falls, looking south to Manilou, which may be seen in 

 the distance. Above the fine automobile road over which the traveler passes on his way to 

 the summit of Pikes Peak are beds of quartzite (hardened sandstone) resting directly on the 

 granite. This unusual contact is not due to a fault but to the fact that the sand was deposited 

 on the granite surface which then formed the floor of the sea. Photograph furnished by the 

 Denver & Rio Grande Western Railroad. 



