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Show 150 EXPLORATION Oli' TflB OANONS OF TllE OOTJORADO. outlines of the topography aro changed, and present angular surfaces, and give rise to another type of topographic features, which I have denominated Alcove Lands. The agencies and conditions under which all of these fentnres have been formed deserve mention, and in this and following chapters I shall briefly discuss this subject, in a manner as free from technical terms as will be consistent with accurate description. The discussion will by no means be exhaustive, and I hope hereafter to treat this subject in a more thorough manner. In view of these facts, I shall not attempt any logical classification of the clements of tho topography, nor of the agencies and conditions under which they were produced; but, commencing at the north, at the initial point of the exploration, I shall take them up in geographic order, as we proceed down the river. BAD-LANDS AND ALCOVE LANDS NORTH 0~, TilE UINTA MOUNTAINS. 1'he area north of the Uinta Mountains embraced in the t;urvey is but small. Through the middle of it runs Groen River, in a deep, narrow valloy, tho sides or walls of which sometimes approach so near to each other, and are so precipitous, as to form a canon. The general surface of tho country, on the north of this district, is about a thousand feet above the river, with peaks, hero and there, rising a few hundred feet higher; but south, toward the Uinta Mountains, this general smface, within a few miles of the river, gradually descends, and at the foot of the mountains we find a valley on either side, with a direction transverse to that ·of the course of Green River, and parallel to the mountain range. To the north, the water-ways are all deeply eroded; the permanent streams have flood-plains of greater or lesser extent, but tho channels of tho wet weather streams, i. e., those which are dry during the greater part of the year, are narrow, and much broken by nb1upt falls. The rocks are the sediments of a dead lake, and are quite vmiable in lithologic characteristics. We find thinly laminated shales, hard limestones, breaking with an angular fracture, crnmbling bad-land rocks, and homogeneous, heavily bedded sand!:itoum;. |