The Physical Geography of the Grand Canyon
The Grand Canyon is a very steep-sided gorge that consists of four plateaus carved by the Colorado River. This geologic incline creates a diversity of biotic communities and it experiences an arid climate which has been instrumental in preserving many prehistoric fossils deep within caves in the Grand Canyon's geologic formations. The springs, seeps and short-living pools provide oases to the existing wildlife in this semi-arid southwest desert area.