CHAPTER II 



ITINERARY. 



GREEN RIVER CITY TO GRANGER. 



The party took the field at Green Eiver City, Wyo., June 1. The 

 first month of the field season was occupied mainly with the survey of 

 the drainage of Green Elver. The second day out from Green Eiver 

 City brought us into our district, and that evening the party eainped 

 at the mouth of the Big Sandy. Fording this shallow muddy stream 

 on the third, the line of march was along its banks to the mouth of the 

 Little Sandy. The next two days the Big Sandy was followed imtd we 

 encamped on the 6th near where it emerges from the foothills of the 

 Wind Eiver Mountains. The Green Eiver Basin, between the Big 

 Sandy and Green Eiver, has on some old maps been called the Great 

 American or Colorado Desert. It is a broad almost unbroken expanse 

 covered with sage (Artemisia) and grass. The prevailing formation is 

 the Green Eiver Group of the Tertiary, consisting of clays, sands, and 

 marls, which on Green Eiver form bluffs a couple of hundred feet high 

 and outcrop in lower bluffs on the Big Sandy. 



Our course so far was in general northerly. Reaching the foothills we 

 skirted them travelling toward the northwest and crossing the various 

 branches of Green River that form the new fork. We reached Green 

 Eiver near our northern line at the mouth of Lead Creek on June 9. 

 Two days later we forded the Green, which was rapidly rising. In a 

 few more days we would have experienced some difficulty in crossing. 



The valleys on Green Eiver, and its branches in the northeast corner 

 of our district, are all broad and well grassed. There are large areas 

 here suitable for agricultural purposes and larger areas valuable for graz- 

 ing lands. The prevailing formation is the Wahsatch Group, which is 

 exposed by the erosion of the overlying Green Eiver Group. The Wah- 

 satch bad-land beds rest on the granitic rocks of the Wind Eiver Mount- 

 ain foothills. The junction is generally obscured by morahial material 

 from the mountains. In a few places, however, the Wahsatch strata are 

 seen. They always incline gently from the mountains toward the Green 

 Eiver Basin, thus indicating a slight elevation of the mountains since 

 the deposition of the beds. 



On the west side of Green Eiver Basin the same beds are seen rising 

 gently as we approach the hills that form the boundary of the basin on 

 the west. The Wyoming Mountains form the boundary toward the north, 

 but as we go south they die out and we have a series of parallel ridges 

 that stand farther to the east. The rocks in the mountains are mainly 

 Carboniferous limestones, but in the parallel ridges to the south we find 

 Triassic, Jurassic, and Cretaceous rocks, the folding of which has caused 

 the ridges. • * 



From the mouth of Lead Creek we travelled southward on the west 



side of the Green, crossing Horse, Marsh, White Clay, Bitteioot, Piney, 



Feather, and Labarge Creeks. Below the mouth of Marsh Creek the 



old Lander road from South Pass to Old Fort Hall crosses the Green. 



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