WALCOTT'S 1879 GRAND STAIRCASE AT KANAB CREEK IN SOUTHERN UTAH AND NORTHERN ARIZONA—ITS REMARKABLE FIRST MEASUREMENT

Charles Doolittle Walcott (1850-1927) was U.S. Geological Survey employee number 20, hired in 1879 by Clarence King, in the first year of the survey's establishment. Earlier reconnaissance geologic mapping in the Utah and Arizona Territories by parties led by Powell and Wheeler had shown that Kanab Creek, a north-trending tributary to the Colorado River just east of the Grand Canyon, displayed a stratigraphic section with Eocene beds in its headwaters near Bryce Canyon, beneath which lay thick deposits of older rocks with Cambrian beds exposed at the Colorado River. This magnificent sequence was spread out in what one of Powell's men, Captain Dutton, had called "The Grand Staircase."

Director King decided that the U.S. Geological Survey had need to know the kinds of rocks, and what fossils those rocks might contain for age determination. He assigned its measurement and description to 29-year-old Charles Walcott. He could not have picked a better person for the task! Beginning as a teenager Walcott had collected fossils from around his home in upstate New York. His first professional employment was as assistant/apprentice to James Hall, the famous New York State Paleontologist. When he went to work for the USGS he was an experienced, energetic, and knowledgeable stratigraphic paleontologist.

Walcott and his field party worked in the Kanab Creek area from 11 August 1879 until 11 November when they left in snowy weather. Using a hand level, chain, and altimeter he measured a stratigraphic section more than 13,000 feet (4,000m) thick. The distance between the top of the section near Bryce Canyon and its base at the Grand Canyon is 80 miles (130 km). He collected age-diagnostic fossils from Cambrian, Devonian, Mississippian, Permian, Triassic, Jurassic, Cretaceous, and Eocene strata. His work established a stratigraphic framework, which subsequent geologists have modified by giving many formational names to the strata he measured. He applied four earlier-coined names—Shinarump, Aubrey, Red Wall, and Tonto—to parts of the Kanab Creek section. Twentieth century mappers and stratigraphers have subdivided Walcott's Kanab Creek section into 35 mappable stratigraphic units, and his 112-year-old study stands as a noteworthy benchmark in geologic work in the Colorado Plateau.