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Show 156 EXPLORATION OF THE CANONS OF THE COLORADO. descending the shaft F. The beds 1-1, 2-2 have been deposited since the ~mergence of the summit of the fold, and hence never extended quite across It; yet the lower members of these beds, doubtless, at one time extended muc.h farther up on .t he flan.k s of the fold · They have b een cu t away, 1. lOW-ever, as represented m the dtagram. Let the lines H H-H H . }' 't f h • 7 1 7 1epresent the IIDI o t e contmuation of these beds In the shafit G th b d I exposed above those seen in shaft F. · ese e s a so are The altitude of the rocks above the line of observation (A B . exaggerated about five times. If they were reduced to one fifth 'th ' ,) IS tion bet th k - ' e proporween . e roc s seen in the various escarpments of these mountains and those earned away below the broken lines would b 1 ' sented. ' e proper Y repre- By sinking a shaft, only a little smface along the edge of the str ta ld be seen; but on the sides of the fold they ar d .r a con e expose 10r many m ·1 d often the top or bottom is cleared off £ 1 es, an rll)ple marks of the an . t or a great space, revealing even the men sea or rounded · · fell in that elder time. or the s~nd h b I~pdresswns of rain drops which . ' s ave une shells a d b f . ammal~;, and they are still d . n ones o anment encase m the rock. d . . leaves that were bmied in tl d ' an oven Impressions of . le mu can yet be seen in such .fi f preservatiOn that you can trace th . d 1. . . a ne state o . etr e 1cate vems. In speakmg of the great upheaval of k fi Mountains . are carved I I k roc s rom which the Uinta ' lave spo en of wrinklin d £ I . . rocks were always flexed. but th d' I g an o dmg, as If the . ' ese 1sp a~ements are t' With fractures on one side of h' h h some Imes attended ' w I c t e rocks are u h d on the other. Such displace t P eave , or thrown down men s are called fault F I · seen in many places in the u· t M . s. au ts hke these are . m a ountams· one . t Side, the throw of which · 1 ' grea one, on the north IS near y twenty thou d £ are found of lesRer magnitude. san eet, and many others In speaking of elevation and d . epress10n by fault' . .r ld' . be understood that reference is d G mg 01 10 mg, It must rna e to a chanO'e f It' d . the surface of the sea so th t h I o 0 a Itu e m relation to , a up eava or throw i I I . eral standard of comparison B t d . sony re attve to this gen- . · u unng the ge I · I m the folding and carvino- of th u· M . o ogiCa ages represented h o e mta ountum . t . . t e sea itself has been changed b l . . s, 1 IS posstble the level of y t le shnnkmg of the ear·th , and a part, THE U lN'fA CANONS. 157 at least, of the apparent upheaval above mentioned may be accounted for by a depression of the formations in synclinal folds, and the letting down of broad areas of the earth's surface by lateral contraction exhibited in corrugation. When we arrive at a point a few miles north of Flaming Gorge, we strike the flank of this great fold, and find the rocks dipping to the north, and, as we run south, the course of the stream is against the inclination of the beds; and this is true, in the main, until we reach Bee Hive Point, where the river turns to the east, almost at right angles to its former course, and to the dip; then it runs nearly in the direction of the strike, but the axis is not crossed until after passing through Red Canon. The rocks on both sides of this canon dip'to the north; that is, they incline to the river on .the south, and from it on the north. Under these conditions, the two walls of Red Canon present very different characteristics; that on the south exhibits steep slopes, covered, to a greater or lesser extent, with forests; the north wall is a bold escarpment, often vertical, and almost treeless; high cliffs, set with pinnacles and towers, and narrow side canons, are its salient features. From the foot of Red Canon to the Gate of Lodore, a distance of more than thirty iniles, the river runs through a valley known as Brown's Park, five or six miles wide, and enclosed by mountains. It is a curious fact that the central line of this valley corresponds to the axis of the fold; that is, had the fold been made, and left without erosion, tho very B!lmmit would have been directly above. the deepest part of the park. When we enter the Gate of Lodore, we are in rocks dipping to the south, having crossed the axis of the fold. From here to Sp1it Mounta-in Canon the general course is south west, he nco not directly across tho dip, but |