Ranger Minute - Rockarena Dance (mov)
Ranger Minutes are short audiocasts or videocasts in which a park ranger shares interesting stories and information about Grand Canyon National Park.
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cut and paste this link into your media player: (7.02MB MOV File)http://www.nps.gov/grca/photosmultimedia/upload/Rmin00804gc-dance.mov
Download the transcript (11kb PDF File)
The Grand Canyon Dance
First of all we’re going to start off with the oldest rocks down at the bottom, that hard metamorphic rock. So let’s get squished under heat and pressure. We’re getting metamorphosed, and as we’re getting squished, we’re getting cracked and faulted, and cracked and faulted. And through those cracks we’re getting magma oozing, and it’s flowing then it freezes.
On top of all that we get limestone, sandstone, shale; ancient oceans, ancient deserts, ancient beaches, ancient swamps; limestone, sandstone, shale; ancient oceans, ancient deserts, ancient beaches, ancient swamps.
And then look out, the North American plate is going to collide with the Pacific plate. Collision…the two plates colliding and we get uplift. One thousand, two thousand, three thousand, four thousand, five thousand, six thousand, seven thousand feet into the sky. We have the Colorado Plateau.
But then look out, the next powerful force, the Colorado River, and the river cuts down, the walls fall in, the river cuts down, the walls fall in, the river cuts down, the walls fall in, and we end up with … Grand Canyon!
How Old Is the Grand Canyon?
Did You Know?
From Yavapai Point on the South Rim of the Grand Canyon, the drop to the Colorado River below is 4,600 feet (1,400 m). The elevation at river level is 2,450 feet (750 m) above sea level. Without the Colorado River, a perennial river in a desert environment, the Grand Canyon would not exist.