An east-west cross-section through the Kaibab Plateau describes before and after scenarios for the evolution of the Kaibab Upwarp; (A) shows that Paleozoic and Mesozoic sedimentary rocks accumulated on the Great Unconformity prior to 80 million years ago, and (B) indicates that reactivation of the Butte Fault by compression during the Laramide Orogeny as a reverse fault produced the East Kaibab monoclinal fold and accompanying uplift.