672 GEOLOGICAL SUEVEY OF THE TERRITORIES. 



canon of the South Platte. This caiion is cut in granite, bordered on 

 the east by a granite plateau, on the west by a high granite range, the 

 continuation of the Kenosha Eauge, which I call the Tarryall Eange, 

 from the large creek which flows along its southern face. The canon is 

 thirty-five ujiles loug, following the general course of the river ; the 

 depth differs greatly in different i^arts, ranging from 400 to 1,000 feet. 

 It is barely passable for pack-animals at the lowest stage of the water. 



The Tarryall Eange lies between the canon of the South Platte, Tar- 

 ryall Creek, and South Park. It is more properly a group of mountains 

 than a defined range. Its elevation reaches, in a few summits, 12,000 

 feet, with an average elevation of 11,000 feet. 



Between Tarryall Greek and the South Platte, the country is open, 

 park-like, and well watered, as also is most of the country lying south 

 of the South Platte. There is plenty of the best of timber and grass. 



South Park is a table-land, very uniform in surface, with the exception 

 of a few minor ridges, which traverse it in a direction generally a little 

 east of south, and in the southern part numerous volcanic buttes. Its 

 shape is nearly elliptical, the longest axis having a direction about north 

 and south, and a length of 50 miles, while its shorter axis is 25 miles 

 long. The area is about 1,000 square miles. The prevailing slope is 

 from northwest to southeast. The elevation is, in the northerft and 

 northwestern part, 9,500 to 10,000 feet; in the western and southwestern 

 part, 8,500 to 9,000, and in the southeastern part, 8,000 feet. The mean 

 elevation is fully 9,000 feet. 



The limits of the park are sharply defined by the mountains, which 

 rise on all sides abruptly from the plains to the highest summits. The 

 Tarryall Eange bounds it on the east as far as Tarryall Creek ; thence 

 to the south end, around the south end, and up the west side as far north 

 as Buffalo Peaks, the boundary consists of wooded hills, having eleva- 

 tions of 10,000 to 11,000 feet, and rising about 2,000 feet above the 

 plain. At Buffalo Peaks the range rises abruptly to mountains :^om 

 13,000 to 14,000 feet high, called the Park Eange, which joins the main 

 range at Mount Lincoln, at the northwest corner of the park. The 

 north end of the park is bounded by the main range, which has there 

 an elevation of 12,000 to 14,000 feet. 



In general the park is not well watered. Near its borders, especially 

 its northern and western sides, there is at all seasons an abundance of 

 good water, but throughout the whole interior part of the park water 

 is scarce. The large streams water but a very narrow belt in their im- 

 mediate neighborhoods, and the smaller streams sink in the gravelly 

 soil. 



The surface of the park is covered with banch-grass of an excellent 

 quality, making it an excellent range for cattle and sheep in summer, 

 but the great elevation makes it extremely hazardous to winter stock 

 out of doors. 



There is no timber except on the sides, but in the mountains there is 

 an abundance of the best timber. 



West of the Park Eange is the valley of the head-waters of the 

 Arkansas Eiver. This is five to ten miles broad, well watered, sparsely 

 timbered, and covered with bunch-grass and sage. From the extreme 

 Tiead of the river in Tennessee Pass to Lake Creek the valley is very 

 broad, open, and fertile. From Lake Creek south about fifteen miles 

 the river is in caiion. Below this is again a broad valley .without 

 timber, and tolerably good for grazing purposes. The whole valley 

 is much more sheltered than South Park, and on that account is much 

 better for wintering stock. 



