peale.] DESCRIPTIVE GEOLOGY SALT RIVER. 553 



snowbanks at the head of the creek, and the gloom of the canon, to the 

 grassy valley, broad and sunny, was a startling one. In the valley there 

 is a straggling growth of cotton woods along the creek, the spaces being 

 filled with willows and other brush. The creek flows rapidly, and its 

 bed is very rocky, without any bordering grassy meadows. 



Between Glacier Creek and Strawberry Creek the valley is broad and 

 level. 



strawberry Creel' rises south of Station 57, and is the only creek that 

 reaches Salt Eiver in this part of the valley. A number of creeks come 

 out from the mountains but sink before they reach the river. From the 

 hills a number of old creek-beds can be distinctly traced by the line of 

 cotton woods, most of which are dead, the withdrawal of the water hav- 

 ing killed them. On the west side of this lower valley of Salt Eiver a 

 large number of small streams come from the hills to the westward, but 

 none of them were visited. The strata composing the hills are evidently 

 the same as those outcropping farther south on Crow Creek and Beaver 

 Creek, but the area between Smoking Creek and Salt Eiver was not 

 traversed by us, so that nothing definite can be said regarding its geo- 

 logical features. Mr. St. John made a section across a portion of the 

 region north of this, and this section indicates the rocks to be similar to 

 those noted in Salt Eiver Gallon at the lower end of the upper valley. 



In the upper valley there are two large creeks joining Salt Eiver from 

 the west, viz, Crow Creek and Smoking Creek. Crow Creek is joined 

 a few miles above its mouth by Beaver Creek. 



Beaver Creel'. — Beaver Creek rises in the low, rounded hills east of 

 the head of Crow Creek and north of the divide between Crow Creek 

 andthe branches of Thomas's Fork of Bear Eiver. At the head there is 

 a marshy valley with a north and south direction. The stream here 

 flows a -little east of south. This valley marks an anticlinal. The few 

 outcrops that can be seen in the hills on the west side of this valley in- 

 dicate a western dip, while on the east side the rocks are dipping east 

 in a ridge extending northwest and southeast. East of this is a second 

 ridge with dips in the same direction. The beds are coarse conglomer- 

 ates, sandstone and limestone pebbles being included. On a third ridge 

 a location was made on a coarse conglomerate containing pebbles of 

 limestone, quartzite, and red sandstone of all sizes and shapes. The 

 beds are pink and reddish in color and are probably the northern con- 

 tinuation of similar beds seen on Thomas's Fork north of Station 41. 



The station just referred to is near the line of a synclinal axis, for on a 

 station just north and a little east we have the conglomerates dipping 

 west ; and east of Beaver Creek here is probably an anticlinal in the gray 

 sandstones. At the second location just mentioned we have the follow- 

 ing beds, showing : 



Section No. 17-J. 



1. Gray sandstones outcropping on both sides of Beaver Creek. 



2. Greenish-gray sandstones forming a hogback-like ridge. 



3. Reddish sandstones and conglomerates. 



4. Coarse conglomerates of the location. 



South of these two locations, Beaver Creek flows towards the east 

 until gradually it begins to turn northward, and flows northward in a 

 monoclinal of gray sandstones. It finally cuts across an anticlinal to 

 its mouth. This anticlinal is probably the anticlinal of station 41 with 

 the beds of the station removed. The divide south of the locations was 

 so high that they could not be traced between the points. Putting 



