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Show GEOLOGY OF THE HIGH PLATEAUS. BY CAPT. C. E. BUTTON. CHAPTER I. GENERAL CONSIDEKATIONS RELATING TO THE TOPOGRAPHY AND GEOLOGICAL HISTORY OF THE HIGH PLATEAUS AND THEIR RELATIONS TO THE PLATEAU PROVINCE OF WHICH THEY FORM A PART. Situation of the High Plateaus.â€"The westernmost range comprising the Pavant, Tushar, and Marka--gmit.â€"Sevier Valley.â€"The second or middle range comprising the Sevier and Paunsagunt Plateaus.â€"Grass Valley.â€"The third range comprising the Wasatch, Fish Lake, Awapa, and Aquarius Plateaus.â€"Structural features of the Park, Plateau and Basin Provinces.â€"-The High Plateaus form the western district of the Plateau Province. â€"Relations of the High Plateaus to the Plateau Province at large.â€"Geological history in outline during Cretaceous time.â€"Interruption of continuity between the Upper Cretaceous and Tertiary.â€"Unconformity between Cretaceous andTertiary.â€"Early Tertiary history.â€"The lacustrine condition of the entire Plateau Province during early Eocene time.â€"Gradual desiccation of this Eocene lake.â€"Cretaceous-Eocene strata occupying its locus at the close of the Eocene.â€"Their vast bulk and gradual subsidence pari passu with deposition.â€" The counterpart of this subsidence, viz, the elevation of the surrounding mountain chains.â€" Post-Eocene history.â€"Erosion.â€"Its conspicuous display and the certainty of its evidence.â€"The drainage system of the Colorado River.â€"Its origin.â€"Its stability of location.â€"Priority of drainage channels to structural features.â€"Their persistence.â€"The methods of erosion.â€"Centers of erosion and the recession of cliffs.â€"The San Rafael Swell.â€"Vastness of the results accomplished by erosion.â€"Effect of the removal of great bodies of strata from large areas.â€"The erosion chiefly accomplished in the Miocene.â€"Summary of the relations of the High Plateaus to the Plateau country at large and to the Basin Province adjoining them on the west. The region to be discussed in this work is centrally situated in the Territory of Utah, occupying a belt of country extending from a point about 15 miles east of Mount Nebo in the Wasatch, south-southwest, a distance of about 175 miles, and having a breadth varying from 25 to 80 miles. The total area of this field of study may approach 9,000 square 1 h p |