It may be modified by other conditions, so that it would not always be the case.
The basin of the Colorado, excepting that part below the mouth of the Virgen and a portion among the "parks" of the western slope of the Rocky Mountain range, is almost entirely a plateau region.

Some of the plateaus are very dry; others rise above the arid zone and are well watered.

The latter are called the "High Plateaus." They reach an altitude of eleven thousand feet above the sea.

They are east of the Great Basin, and with the other plateaus form an area called by Powell "The Plateau Province." Eastward still the plateaus merge into the "parks." The High Plateaus, as a topographical feature, are a southern continuation of the Wasatch Mountains.

They terminate on the south in the Markagunt, the Paunsagunt, and the Aquarius Plateaus.