Grand Canyon boasts a long lineage of professional geologists who have toiled here for nearly 150 years unraveling the Canyon's many closely held secrets. Edwin "Eddie" McKee, who was also the founder of the Grand Canyon Natural History Association (today's Grand Canyon Association), was one of these "geology all-stars."
McKee's love for and long affiliation with the Grand Canyon inspired the stellar career that earned him the respect of his fellow North American geologists. McKee's link to Grand Canyon began in his hometown of Washington, D.C., and was initiated by his Boy Scout Troop Master, François Matthes, himself one of the canyon's well-known geologists. In 1927, Matthes arranged a summer internship for McKee at the canyon with the famous paleontologist John C. Merriam.
McKee's interest in geology sprouted while he interned, and he later enrolled in the geology program at Cornell University. Tragedy, however, brought him back to the Grand Canyon in 1929, when park naturalist Glen Sturdevant drowned while crossing the Colorado River on patrol. The park asked McKee to fill that park naturalist vacancy. As it turned out, the canyon would change McKee's personal as well as professional life; by the end of 1929, he married botanist Barbara Hastings, who worked across the canyon on the North Rim.
Ironically, McKee courted Miss Hastings by hiking up the North Kaibab Trail‹the same trail that François Matthes had pioneered on his mapping survey in 1902.
As park naturalist, McKee developed wide-ranging scientific interests at Grand Canyon. His contributions to Grand Canyon science included studying the park's butterflies and birds, collecting and cataloging Havasupai basketry, and developing lectures on the Grand Canyon that he presented to park visitors.
McKee was the "discoverer" of the Grand Canyon pink rattlesnake; he came upon one while hiking on the Tanner Trail. He carried the live specimen out of the canyon and drove to Grand Canyon Village with the snake at arm's length out the car window.
Geology became McKee's primary passion, as his many field excursions brought him into close contact with the most immense and beautiful exposure of stratified rocks on Earth. As a result of his time spent within the embrace of Grand Canyon, McKee became one of the foremost experts on stratigraphy (the study of strata). His first scientific paper, "The Coconino Sandstone: Its History and Origin," was published by the Carnegie Institution in 1933.
McKee was most likely influenced in this endeavor by Dr. David Gilmore, one of McKee's supervisors during his 1927 internship and the first paleontologist to study the reptile trackways along the Hermit Trail. These tracks strongly suggested that the Coconino Sandstone was a deposit of terrestrial origin, specifically in an eolian (wind-blown) dune setting.
The Grand Canyon Cross-Bedding Club assisted McKee in this study. This loosely knit group of fellow canyon residents shared McKee's interest in geology and helped him measure the angle and orientation of the Coconino's many cross-beds. McKee seemed to touch many residents with his passion for rocks.
His 1938 paper, "The Environment and History of the Toroweap and Kaibab Formations in Northern Arizona and Southern Utah," was among the first studies to document the subtle changes in texture and composition that a rock layer sometimes exhibits when examined at separate locations.
These observations helped define the concept of "facies change" in sedimentary rocks, whereby obscure lateral changes in rock composition and texture record the subtle environmental changes that occurred in the ancient past.
In this study, McKee showed that the Toroweap and Kaibab seas originated in a setting with deeper ocean water to the west, which, over time, slowly transgressed (spread) to the east.
Emboldened by his stratigraphic studies near the rim of the canyon, McKee turned his attention to the Tonto Group near the river, research published in the paper "Cambrian History of the Grand Canyon Region" (1945). He discovered that this tripartite group of rocks had a more complex assemblage of strata than was apparent at first glance. Close examination of the fossils and strata revealed that the age of a particular rock formation in one part of the canyon was noticeably different elsewhere in the canyon.
He determined that the Tonto Group was "time-transgressive," that is, at any one time three different environments existed across the Grand Canyon region. From west to east, the environments were deeper water (Muav Limestone), shallow water (Bright Angel Shale) and shoreline settings (Tapeats Sandstone).
McKee also determined that these ancient environments migrated in lock step toward the east through time. Each environment left a specific sediment type, such that when the Muav was being deposited near today's Grand Wash Cliffs, the Bright Angel Shale was being deposited near the area of Supai Village and the Tapeats in the vicinity of Grand Canyon Village.
These observations had implications for the science of geology far beyond the realm of Grand Canyon.Also in 1945, McKee became the first person to apply formation names to rocks near Sedona, Ariz.
He used his knowledge of Grand Canyon stratigraphy to determine an almost identical sequence of rocks there. In 1964 McKee convened the first symposium on the origin of the Colorado River, and he published a paper from the symposium, "Evolution of the Colorado River in Arizona," three years later. His passion for eolian sand deposits, which began with his studies of the Coconino Sandstone in Grand Canyon, led him to field research in the Sahara, Namib and Gobi deserts, research he later published as "A Study of Global Sand Seas" (1979).
His last major project at Grand Canyon integrated his interest in sandstones with his affection for the Havasupai people, research he published as "The Supai Group of Grand Canyon" (1983). In this paper, McKee detailed the depositional history of these delta and river deposits, and he named three new formations within the Supai Group after Havasupai family names.
McKee's work remains influential among geologists, but his personal relationship to the Grand Canyon is sometimes overlooked.
John C. Merriam directed the construction of the museum on Yavapai Point in the 1920s, and Eddie McKee inspired many park visitors with geology talks he presented there.
Editor's note: Wayne Ranney is an instructor of geology at Yavapai College and Coconino Community College. He is the author of "Carving Grand Canyon: Evidence, Theories, Mystery" (2005), published by the Grand Canyon Association.