CHAPTER X. 

 SEVIER VALLEY AND ITS ALLUVIAL CONGLOMERATES. 



The headwaters of Sevier River.— Upper Sevier, or Panquitch Valley. — Panquitch Cation. — Circle Val- 

 ley. — Origin of the Sevier Valley. — Conglomerates. — Their various kinds. — Sources of the mate- 

 rials. — Transportation of coarse ddbris and the natural laws governing it. — Action of rivers upon 

 transported materials. — Action of the sea. — Alluvial conglomerates. — Formation of alluvial cones 

 at the openings of mountain gorges. — Their structure. — Alluvial cones now forming in the val- 

 leys of the district. — A comparison between the modern alluvial formations and the ancient con- 

 glomerates. — Identity of the process which formed both. 



The South Fork of the Sevier River heads in the Markagunt near its 

 southwestern crest, the springs being scattered among the basalt fields, 

 which cover a considerable area in that vicinity. Two fine creeks flow 

 eastward in broad valleys, meandering down the slopes of the plateau until 

 they meet the opposite slopes which descend from the western wall of the 

 Paunsagunt. Here the southernmost creek (Asa's Creek) is deflected north- 

 ward, and 6 miles below, Mammoth Creek joins it, the two forming the South 

 Fork of the Sevier. Thence northward the stream flows for more than 50 

 miles, receiving a few insignificant tributaries, until at the foot of Circle Val- 

 ley it is joined by the East Fork issuing from a mighty chasm, which cuts 

 from top to bottom the great Sevier Plateau. Still northward it pursues 

 its course nearly a hundred miles more, receiving one important affluent at 

 Salina and another at Gunnison, until it suddenly springs westward at the 

 Pavant and cuts a chasm through it; then turning south-southwest, it mean- 

 ders through a forlorn desert for about 60 miles, and ends at Sevier Lake, a 

 large, nauseous bittern of the Great Basin. The site of this lake was at 

 a recent epoch covered by a southward extension of Lake Bonneville. It 

 is interesting to reflect that as late as Post-Glacial time the waters which 

 fell upon the crests of the Pink Cliffs of Southern Utah were there divided; 

 a part to flow southward into the Grand Canon, the remainder to flow north- 



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