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Show 204 GEOLOGY OF THE HIGH PLATEAUS. tinguishable in composition and texture from ordinary sediments derived from ordinary materials. Nor is their exact age assignable, since they have yielded no fossils, but the probabilities are great that they are not far from middle Eocene age. Beneath them lies what is called the Pink Cliff series, which is known to be Lower Eocene.* At the base brackish-water fossils are found, which give place as we ascend to a fresh-water fauna. The upper members are limestones, which are usually more or less siliceous, and the silica increases in the lower members, where gravelly beds, layers of sandstone, and even conglomerate are found. The highly calcareous members strongly predominate. The coloring is always striking and vies in brilliancy with the Triassic beds. The highest member is frequently almost snow-white, with a band of strong orange-yellow beneath it. But the great mass of color is a pale rosy-pink. When the sun is low and sends his nearly level beams of reddish light against the towering fronts and mazes of buttresses, alcoves, and pinnacles, they seem to glow with a rare color, intensely rich and beautifulâ€"flesh-of-watermelon color is the nearest hue I can suggest. Some of the beds do not naturally possess this color, but have been painted superficially by the wash from the beds above them, or possibly have taken on the color through exposure, while they are yellow within. The identity of these beds with the Bitter Greek of the Wasatch Plateau and of the Uintas seems clear. The connection by actual continuity is, indeed, wanting, but the fossils, though few, are convincing, and the relations to the Cretaceous beneath are strictly homologous to those which prevail farther north. Some doubt arises whether the white limestone which caps the series should be referred to the Bitter Creek or to the Green River beds. Mr. Howell, whose opinions are of great weight, inclined to the latter view, and thought that one of the members of the Wasatch Plateau (No. 2), which I have referred to the Lower Green River period, was wanting, and that the white limestone should be correlated to those beds which I have referred doubtfully to the Upper Green River. It is true that two * I use the term Eocene in its local sense. It may or may not be coeval with the European Eocene. Probably it is very nearly so. « |