コロラド高原
The entire Colorado Plateau then started to uplift from near sea level to several thousand feet (over a kilometer) in elevation. An alternate theory is that the Laramide orogeny uplifted what is today the Basin and Range and the Colorado Plateau and that the tensional forces that formed the Basin and Range caused that region to subside relative to the Colorado Plateau. Whatever the order of events were, the High Plateaus region of the Colorado Plateau were by now nearly complete.