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Show 166 EXPLORATION OF 'l'IIE OARONS OF T£IE COLORADO. in the rocks through which tho channels are now carved, but that the beds in which the streams had their origin when the district last appeared above the level of the sea, have been swept away. I propose to call such superimposed valleys. Thus the valleys under consideration, if classifie~ on the basis of their relation to the rocks in which they originated, would be ca.llod conseqvent valleys, but if classified on the basis of their relation to the rocks in which they are now found, would be called superimposed valleys. Recurring again to the valleys of the Uinta Mountains, it may be well to remark here that, coming from the Rocky Mountains to the study of the Uinta Mountains, I at first supposed that the valleys of this region a1do were superimposed upon the rockB now seen, but gradually, on a more thorough study, the hypothesis was found to be not only inadequate to the explanation of the facts, but to be entirely inconsistent with them; and again and again I visited the region, and re-examined tho facts, and at last reached the . conclusion which I have heretofore stated. A brief reference to the character of this evidence may not be out of place here, though I ~:eserve the subject for a more full discussion in my report on the geology of the Uinta Mountains. If the valleys were superimposed on the present rocks, they must be consequent to rocks which have been carried away; but the valleys consequent upon the corrugation, which was one of the conditions of the origin of the Uinta Mountains, could not have taken the direct~on observed in this system; they would have all been cataclinal, as they ran down from the mountains, and turned into synclinal valleys at the foot, forming a very different system from that which now obtains. Again, the later sedimentary beds, both to the north and south, were found not to have been continuous over the mountain system, but to have been deposited in waters whose shores were limited by the lower reaches of the range; that is, they all gave evidence of littoral oli()'in and further, that the principal caiions through the mountains had beebn c'a rved' nearly to their present depth before the last of these sediments were deposited. BAD-LANDS AND ALCOVE LANDS SOUTH OF THE UINTA MOUNTAINS. South of the Uinta Mountains, and beyond the hog-backs on either side of the river, is a disttict known t<> thu Indians as Wa-ka-ri' -chits or tho ' |