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Show 252 GEOLOGY OF THE HIGH PLATEAUS. unconformable. In the cliffs of the eastern and southern margins the following series is presented: Feet. 1. Gray calcareous sandstone.............................................. 180 2. White limestone...................................................... 160 3. Bed marly limestones and calcareous shales......................... .. 300 4. Eed pinkish limestone.................................................. 450 5. Conglomerate, with small pebbles and gravelly sandstone.................. 190 1,280 Below these are the characteristic gray Cretaceous shales, somewhat arenaceous, forming long spurs and foot-hills. They do not here form cliffs, but long slopes, descending into the lower regions adjoining. From the southern extremity of the Paunsagunt they rise with a slight inclination towards the south and are beveled off by erosion. At one point the section crosses (southward) a decided monoclinal flexure with a maximum dip of about 10° to 12° trending east and west, but quickly reflexing back to a dip of 3° to 4°. One after another \he formations end in cliffs and ledges, and the profiles drop at each crest-line upon lower beds, until at a distance of about 23 miles from the southern end of the plateau the carboniferous forms the final platform, and rises gently but continuously to the Grand Canon. The western side of the plateau looks down from its northern half upon the valley which carries the upper waters of the South Fork of the Sevier River. Across this valley the gentle slopes of the Markagunt rise towards the west. Along this base of the Paunsagunt runs the Sevier fault, but before reaching the end of the plateau its course changes from south to the southwest. Just where this change occurs is the divide between the valley of the Sevier and the headwaters of the Virgin, a tributary of the Colorado. The wall of the plateau thenceforward becomes a cliff of erosion gradually swinging to the southeast, then around the end of the table (which projects southward like a great promontory), and finally trends to the northward. The summit of the table has a central stream which gathers all the drainage and carries it northward to the Panquitch Hay-field, thence into the East Fork by the way of Grass Valley, and finally through East Fork Canon into the Sevier River. |