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Show SALINA CANONâ€"THE JUBASSIC WEDGE. 163 it has now become a generalization of great importance. Its formula is exceedingly brief Tlie principal drainage channels are older than the displacements. Salina Canon cuts through the southern continuation of the great monoclinal at a point where its rise is a minimum, and nearly midway between the Wasatch Plateau on the north and the Sevier and Fish Lake Plateaus on the south. Even here it plunges into a wall forming the uplifted side of a great fault of which the shear could not have been much less than 3,000 feet, though fully 2,000 feet of upper beds have been removed from the uplift by erosion. After a course of about 23 miles the canon opens into the Sevier Valley. It carries a fine stream, whose waters join the Sevier at the town of Salina. Along the descent of this stream the beds dip more rapidly than the stream descends. This relation between the course of a drainage channel and the inclination of the strata is not the usual one in the Plateau Country; on the contrary, the strata much more frequently dip upstream, and rivers usually emerge from cliffs instead of entering them. In this respect Salina Canon is an exception, though not an isolated one. A remarkable displacement is found along the eastern side of the Sevier Valley, between Gunnison and Salina. A narrow belt of rocks of Jurassic age is thrust up, forming a chain of foot-hills and bad lands, and the later Tertiaries are seen to flex upward against their western sides and terminate in a "hog-back," while they abut almost horizontally against their eastern sides. A small remnant of Tertiary beds is here and there found as a thin capping lying upon the Jurassic beds unconformably, and patches of volcanic rock farther southward are also seen to cover them. The belt of Jurassic rocks nowhere exceeds two miles and a half in width, but its length is nearly 40 miles, extending from a point about 7 miles south of Manti along the base of the great monoclinal and the throw of the Sevier fault as far as Monroe, where it ends, to all appearances,- somewhat abruptly, or perhaps disappears under the great mass of volcanic rocks which form the loftiest part of the Sevier Plateau. These older beds dip eastward, always at a high angle, which sometimes passes the vertical. This inclination was attained, without doubt, in part before the commencement |