How Old?The rocks exposed within Grand Canyon range from the fairly young to old. Kaibab limestone, the cap-rock on the rims formed 270 million years ago. The oldest rocks within the Inner Gorge at the bottom of GC date to 1,840 million years ago. For comparison, geologists currently set the age of Earth at 4,550 million years.
How New?
While the rocks are ancient, the canyon is young. Geologists generally agree that canyon carving occurred over the last 5-6 million years - a geologic blink of the eye!
The photograph is the river level view of the canyon.
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