CHAPTER IV. CLIFFS AND TERRACES.
Now let us see what all this means. In order clearly to understand this explanation the reader is referred to the illustration designated "Section and Bird's-Eye View of the Plateaus North of the Grand Canyon." Starting at the Grand Wash on the west, the Grand Wash Cliffs, formed by the Grand Wash Fault, are scaled; and if we are but a few miles north of the Grand Canyon we are on the Shiwits Plateau. Its western boundary is the Grand Wash Cliffs, its southern boundary is the Grand Canyon, and its northern boundary is a line of cliffs of degradation, which will be described hereafter. Going eastward across the Shiwits Plateau the Hurricane Cliffs are reached, and climbing them we are on the Uinkaret Plateau, which is bounded on the south by the Grand Canyon and on the north by the Vermilion Cliffs, that rise above its northern foot. Still going eastward 30 or 40 miles to the brink of the Kanab Canyon, the West Kanab Plateau is crossed, which is bounded by the Toroweap Fault on the west, separating it from the Uinkaret Plateau, and by the Kanab Canyon on the east, with the Grand Canyon on the south and the Vermilion Cliffs on the north. Crossing the Kanab, we are on the East Kanab Plateau, which extends about 30 miles to the foot of the West Kaibab Cliffs, or the escarpment of the West Kaibab Fault. This canyon also has the Grand Canyon on the south and the Vermilion Cliffs on the north. Climbing the West Kaibab Fault, we are on the Kaibab Plateau. Now we have been climbing from west to east, and each ascent has been made at a line of cliffs. Crossing the Kaibab Plateau to the East Kaibab Cliffs; the country falls down once more to the top of Marble Canyon Plateau. Crossing this plateau to the eastward, we at last reach the Echo Cliff Fault, where the rocks fall down on the eastern side once more; but the surface of the country itself does not fall down - the later rocks still remain, and the general level of the country is preserved except in one feature of singular interest and beauty, to describe which a little further explanation is necessary.
I have spoken of these north-and-south faults as if they were fractures; and usually they are fractures, but in some places they are flexures. The Echo Cliffs displacement is a flexure. Just over the zone of flexure a long ridge extends from north to south, known as the Echo Cliffs. It is composed of a comparatively hard and homogeneous sandstone of a later age than the limestones of the Marble Canyon Plateau west of it; but the flexure dips down so as to carry this sandstone which forms the face of the cliff (presented westward) far under the surface, so that on the east side rocks of still later age are found, the drop being several thousand feet. The inclined red sandstone stands in a ridge more than 75 miles in length, with an escarped face presented to the west and a face of inclined rock to the east. The western side is carved into beautiful alcoves and is buttressed with a magnificent talus, and the red sandstone stands in fractured columns of giant size and marvelous beauty. On the east side the declining beds are carved into pockets, which often hold water. This is the region of the Thousand Wells. The foot of the cliffs on the east side is several hundred feet above the foot of the cliffs on the west side. On the west there is a vast limestone stretch, the top of the Marble Canyon Plateau; on the east there are drifting sand-dunes.
The terraced land described has three sets of terraces: one set on the east, great steps to the Kaibab Plateau; another set on the west, from the Great Basin region to the Kaibab Plateau; and a third set from the Grand Canyon northward. There are thus three sets of cliffs: cliffs facing the east, cliffs facing the west, and cliffs facing the south. The north-and-south cliffs are made by faults; the east-and-west cliffs are made by differential degradation.
The stupendous cliffs by which the plateaus are bounded are of indescribable grandeur and beauty. The cliffs bounding the Kaibab Plateau descend on either side, and this is the culminating portion of the region. All the other plateaus are terraces, with cliffs ascending on the one side and descending on the other. Some of the tables carry dead volcanoes on their backs that are towering mountains, and all of them are dissected by canyons that are gorges of profound depth. But every one of these plateaus has characteristics peculiar to itself and is worthy of its own chapter. On the north there is a pair of plateaus, twins in age, but very distinct in development, the Paunsagunt and Markagunt. They are separated by the Sevier River, which flows northward. Their southern margins constitute the highest steps of the great system of terraces of erosion. This escarpment is known as the Pink Cliffs. Above, pine forests are found; below the cliffs are hills and sand-dunes. The cliffs themselves are bold and often vertical walls of a delicate pink color.