234 GEOLOGICAL SURVEY OF THE TERRITORIES. 



chiefly of boulder ridges and plateaus, with washed and bluffy escarp- 

 ments, in consequence of which the term "bad lands" is sometimes 

 applied to it. This section is partially supplied with streams bordered 

 with narrow arable strips, which can be irrigated, and, notwithstanding 

 •;heir barren appearance, are really quite fertile. The southwest corner 

 is broken and mountainous and contains very little land that can be 

 cultivated, but includes some line grazing fields. The northern triangu- 

 lar section, lying between the Wind Eiver and Wahsatch Mountains, 

 contains the greater part of the arable land in the district, and is di- 

 vided into three distinct parts or sub-sections, as follows : the Green 

 River Valley, the Big Sandy Valley, and the broad, somewhat elevated 

 plains lying between them. 



Green Eiver, rising in the Wind Eiver Mountains near Fremont's 

 Peak, runs in a southerly direction for about one hundred and twenty 

 miles to the 42d parallel, where it turns southeast, and is joined by Big 

 Sandy, where it crosses the 110th meridian. It continues the same 

 course, after receiving the waters of the Big Sandy, to the crossing of the 

 Union Pacific Eailroad, where it again turns south and passes out of 

 the Territory. Between its source and the 42d parallel it is joined by a 

 number of small affluents that flow down from the mountains on' the 

 west, the more important of which are, Lead Horse, Marshy, White 

 Clay, Butternut, Piney, La Barge, Fontenelle, and State Creeks. 



Although I have not had an opportunity of a full examination of this 

 part of the section, yet I am satisfied there must be a large amount of 

 arable land that can be irrigated by the waters of these creeks. And 

 this opinion is strengthened by observing the volume of water in the 

 river above its junction with the Big Sandy, for where we crossed it in 

 September, (the time of year when its waters are low,) it was about one 

 hundred and twenty feet wide, with an average depth of fifteen inches, 

 and running very swiftly. There is but one stream of any importance — 

 the IsTew Fork — that comes in from the east, but this is the longest trib- 

 utary north of the bend. 



I do not know what the fall of the river is, but it must be considerable, 

 as its current is rapid and its bottom, where I saw it, covered with clean 

 round pebbles. I suppose it cannot be less than eight or ten feet to the 

 mile, which is sufficient to reach the surface of the broad plateau that 

 spreads out east of it. If I am correct in my conclusions, it will be pos- 

 sible to irrigate a body of land equal to the entire capacity of the stream, 

 and we may therefore safely estimate the amount of land in this section 

 which can can be brought under cultivation at eight or nine hundred 

 square miles. It is true this estimate is based on slender data, but I 

 think it cannot be too large, for the Green Eiver bottoms alone will 

 make one-fourth of this amount, while the larger irrigable area is on the 

 second level or table lands, which vary from fifteen to fifty feet in height, 

 above the waters of the stream and spread out to great width. The 

 broad tract that sp-reads out between this river and Big Sandy is level 

 and sandy, presenting a barren and desolate appearance, on which ac- 

 count it is sometimes called "The Colorado Desert." It is covered with 

 a low growth of Artemisia, and a close examination of the soil shows that 

 it possesses the elements of fertility, and only needs the addition of water 

 to make it productive. Although the supply of water from Green Eiver 

 is not sufficient to irrigate all this extensive tract it will furnish a broad 

 belt of it. The Big Sandy rises in the Wind Eiver range a few miles to the 

 northwest of South Pass, and runs south until it is joined by the Little 

 Sandy — its principal tributary — when, bending southwest, it continues 

 this course until it joins Green Eiver. The upper portion passes almost 



