Grand Canyon Geology
The Grand Canyon has been a constant presence in my work and thought for 45 years. This has provided the opportunity to become well acquainted with the geology of this extraordinary place. Much of the effort was devoted to the origin of the Canyon: when was it cut, how fast, and through what mechanisms? The most recent work, however, was done as part of a program designed to understand the effects of Glen Canyon Dam downstream in Grand Canyon National Park. My team's task was to study the Quaternary geology as a means of providing a background against which the effects of the dam could be evaluated. The resulting insights are useful in a variety of contexts having to do with the Grand Canyon and its Colorado River. One of the more interesting is the effect of changing geologic environments on the prehistoric puebloan farmers that once inhabited the area.