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Show 152 EXPLORATION OF THE OANONS OF THE OOLORADO. exposure to the air, the chemical agencies give a greater variety of colors, so that the mountains and cones, and tho strange forms of the bad-lands, are elaborately and beautifully painted; not whh the delicate tints of verdure, but with brilliant colors, that are gorgeous when first seen, but which soon pall on the senses. Tim UINTA MOUNTAINS. To the west of Green River stand the Wasatch Mountains, a system of peaks, tables, and elevated valleys, having a northerly and southerly direction, nearly parallel to the river. rrhe range known as the Uinta Mountains stands at right angles to tho Wasatch, extending toward the east, and no definite 1ine of division can be noticed. The Wasatch is a great trunk, with a branch callBd the Uinta. Near the junction, the two ranges have abont the same altitude, and the gulches of their summits are filled with perpetual snow; but toward the east, the Uinta peaks are lower, gradually diminishing in altitude, nntil they are lost in low ridges and hills. Through this range Green River runs, and a series of cafions forms its channel. To a person studying the physical geography of this country, without a knowledge of its geology, h would seem very stmnge that the river should cut through the mountains, when, apparently, it might have passed around them to the east, through va11eys, for there are such along the north side of the Uintas, extending to the east, where the mountains are deO'raded to hills d . b ' an , passmg ~round these, there are other valleys, extending to the Green, on 11he south s1de of the range. Then, why did the river run through the mountains Y , The first explanation suggested is that it followed a previously formed fissure through the range; bnt very little examination will show that this explanation is unsatisfactory. The proof is abundant that the river cut its own .channel; that t~e cafions are gorges of corrasion. Again, the question retums to us, why did not the stream turn around this great obstruction, rather tl~an pass through id 'rhe answer is that the river had the riO'ht of way; m other words, it was running ere the mountains were formed. ~ot before the rocks of which the mountains aro CODlJJOsed Wel·e d 't d' h ,, c 1 . ' epos1 e , ut ue.ore t 1e formations were folded ' so as to make a moun t am· range. THE RIVER OLDEH THAN TDE MOUNTAINS. 153 The contracting or shriveling of the earth causes the rocks near the smface to wrinkle or fol'd, and such a fold was started athwart the course of the river. Had it been suddenly formed, it would have been an obstruction sufficient to turn the water in a new course to the east, beyond tho extension of the wrinkle; but the emergence of the fold above the general Rmface of the country was little or no faster than the progress of the corrasion of the channel. We may say, then, that the river did not cut its way down through the mountains, from a height of many thousand feet above its present site, but, having an elevation differing but little, perhaps, from what it now has, as the fold was lifted, it cleared awa.y the obstruction by cutting a canon, and the walls were thus elevated on either side. 'J:'he river preserved its level, but mountains were lifted up; as the saw revolves on a fixed pivot, while tho log through which it cuts is moved along. The river was the saw which cut the mountains in two. Recurring to the time before this wrinkle was formed, there were beds of sandstone, shale, and limestone, more than twenty four thousand feet in thickness, spread horizontally over a b1·oad stretch of this country. Then the E!ummit of the fold slowly emerged, until the lower beds of sandstone were lifted to the altitude at first occupied by the upper beds, and if these upper beds had not been carried away, they would now be found more than twenty four thousand feet above the river, and we should have a billow of sandstone, with its axis lying in an easterly and westerly direction, more than a hundred miles in length, fifty miles in breadth, and over twenty four thousand feet higher than the present altitude of the river, gently rounded from its central line above to tho foot of the slope on either side. But as the rocks were lifted, rains fell upon them and gathered into streams, and the wash of the rains and the corrasion of the rivers cut the billow down almost as fast as it rose, so that the present altitude of these mountains marks only the difl'creuce between the elevation and the denudation. It has been said that the elevation of tho wrinkle was twenty-four thousand feet, but it is probable that this is not the entire amount, for the present altitude of tho river, above the sea, is nearly six thousa.ncl feet, and when this 20 COL |
