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GUIDEBOOK or THE WESTERN UNITED STATES. 



After journeying through the canyon for about 20 miles the trav- 

 eler will probably be glad to leave it and to gain the upland, where 

 he may see something more than rugged rock walls and muddy river. 

 If the vegetation on the upland is not parched and dried by the sum- 

 mer's heat, the sego lily, Utah's floral emblem (PI. LXXXI), may 

 be seen here and there lifting its delicate head, though it stands so 

 close to the ground that it is difficult to identify from the moving 

 train. The wide expanse of upland also enables one to see the larger 

 features of the surrounding landscape. One of the first objects to 

 catch the eye on the left is a distant group of mountain peaks — the 

 La Sal Mountains — whose highest point reaches an altitude of about 

 13,000 feet. One unaccustomed to judging distances in the clear air 

 of an arid country can not say whether these mountains when first 

 seen are 10 or 50 miles away, but careful measurement has shown that 

 the nearest peak is about 30 miles distant. This mountain group 

 was formed by the uplifting of the rocks in a great domelike mass, 

 and if the light is just right the traveler may see the great cliff-like 

 wall of red sandstone, with which he is now becoming familiar, on 

 the east side of the mountains, where it has been uptilted by the 

 movement. This group of mountains will be in sight for some time, 

 and a little farther west it can be seen to better advantage. 



The railroad winds about in the low hills of the McElmo forma- 

 tion, which in places are somewhat picturesque on account of the 

 great variety of their colors, but in general the outlook is not par- 

 ticularly pleasing. The scene, however, may be of great interest to 

 one not familiar with it, for it gives him a good idea of the utter 

 barrenness of a region where the rainfall is as scanty as it is in Grand 

 County, Utah. In places the rocks are very dark, and the traveler 

 may think that they have been baked to this dark color by volcanic 

 fires and that many of the rock fragments are pieces of lava. The 

 geologist, however, knows that the rocks of this region are not vol- 

 canic. In fact, all the rocks composing the McElmo and Gunnison 

 formations were laid down as sediments in lakes or ponds or in 

 the beds of streams, and the dark rocks are only those that contain 

 considerable iron, or those that have been coated by so-called " desert 

 varnish," a dark substance, probably in large part manganese, which 

 tends to cover all exposed rocks in the desert region and to give 

 them a black color. It is from the McElmo and La Plata formations 

 or their equivalent, the Gunnison formation,®^ that most of the ores 



°^ In the region between Denver and 

 Salt Lake City the formation immedi- 

 ately beneath the Dakota sandstone 

 bears a number of names, which are 

 exceedingly confusing to anyone who is 

 unfamiliar with tae rocks and their 



relations. Thus along the Front 

 Range the Morrison is a well-marked 

 formation of variegated shale and 

 sandstone whose age is uppermost 

 Jurassic or lowermost Cretaceous. It 

 is a fresh-water formation and con- 



