The Grand Canyon and Terrace Plateau Region.
This covers and area in Southern Utah and Northern Arizona 144 iles square, containing more marvels than any other part of the globe of equal extent. In the lower right-hand corner are the Yosemite Valley and the Gorge of Niagara on the same scale. The scale of this reduction is about 14 miles to one inch. The vertical and horizontal scales are the same. The black ribbon on the left at Virgen and Beaver Dam Mountains is to represent Archæan formation. The Shivwita Plateau and Uinkaret Mts. are basaltic. The Kaibab and the Colorado Plateau are Carboniferous. Paria Plateau and Vermilion Cliffs are Triassic. The Markagunt and Paunsagunt Plateaus are Tertiary. Cardenas reached the canyon about at letter “A” of the word “Cañon.” Tourists now come to the river about half way between the letters “L” and “O” of the word “Colorado.” The largest settlement is the charming little Mormon city of St. George, on the Virgen, north of the letter “A” of the word “Arizona.” Grand and Marble Canyons form a continuous gorge about 300 miles long, a complete barrier to travel for this distance as its walls are precipitous and reach a height of between 5000 and 6000 feet—4000 being about the average. The lowest portion is toward Lee’s Ferry, upper right-hand side of the map, where the walls begin at a couple of hundred feet and rise very rapidly, the river cutting down also. The relief map from which this photograph was made was modelled by E. E. Howell for the U. S. Geological Survey and is 6 x 6 feet.
