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Show 208 GEOLOGY OF THE HIGH PLATEAUS. uniformity over miles of exposure and contrasting with each other by their varying shades of chocolate, dark red, and purple, producing an effect of colored bands of small thickness individually but great collectively, and with a perfect regularity or parallelism. (See Heliotype No. XI.) The Lower Mesozoic series (Jura and Trias) is found in the Markagunt only in the immediate vicinity of the great Hurricane displacement, which defines the western boundary of the structure, and is only seen there along the southern portion of the west flank. I have not visited them, but Mr. Howell has examined them somewhat cursorily, and the results of his observations, in the form of notes, are before me. There is a general agreement of the sections he there found with the general section of the Plateau Country to the eastward, though there are minor differences which might be worthy of future study. All of the notable Mesozoic groups and beds are present and seem to be on the whole somewhat thicker than they are to the eastward, but the thickness is more variable and the deposition generally more unequal. In close proximity to the great fault, the beds are in some places flexed abruptly upwards on the uplifted side of the fault, but in passing eastward they speedily recur to the general east or east-northeast dip of 1° to 2° which prevails throughout the plateau. Nowhere in this vicinity does the Carboniferous seem to be exposed, though in several localities it must be very near the surface in the immediate line of the fault. Where these upward flexures occur, the plane of denudation between the summit of the plateau and the fault cuts across the entire series of Mesozoic and Cenozoic formations more than 10,000 feet in thickness. From the southwest salient of the Markagunt we behold one of those sublime spectacles which characterize the loftiest standpoints of the Plateau Province. Even to the mere tourist there are few panoramas so broad and grand; but to the geologist there comes with all the visible grandeur a deep significance. The radius of vision is from 80 to 100 miles. We stand upon the great cliff of Tertiary beds which meanders to the eastward till lost in the distance, sculptured into strange and even startling forms, and lit up with colors so rich and glowing that they awaken enthusiasm in the most apathetic. To the southward the profile of the |