By Dennis Schatz - Vice President of Strategic Development
The question in this edition is:
How old is the Grand
Canyon?
The Answer - 2 Bil Years
Scroll down to see the solution to our
puzzle.
The answer to the question depends on whether you want to
know when the erosion started that produced the Grand
Canyon or how old are the rocks found in the Grand Canyon.
Until recently it was thought the Colorado River started
creating the canyon about 6 million years ago. But a
→study released earlier this year
provided evidence that the
erosion that formed the canyon began 17 million years
ago. But the rocks exposed by the river are much older,
from two billion years old at the bottom to 230 million
years old near the rim. For more information regarding
how the Grand Canyon formed check →kaibab.org.
The Grand Canyon is 277 miles long, varies in width from 4
to 18 miles and is more than a mile deep in places. A big
challenge today is the way humans have changed the flow of
the Colorado River. Ten dams and 80 other diversions
generate electricity, provide drinking water to cities and
irrigate land to grow crops. Sometimes so much water is
taken out of the Colorado River that the river dries up
before reaching the Gulf of California. These changes have
endangered many native species that live along the river.
The Colorado River and the Grand Canyon are a perfect
example of the challenge humans face to supply the useable
water needed by a growing human -- and non-human --
population. Learn more about this dilemma by seeing
Grand
Canyon Adventure 3D: River At Risk, now showing at our Boeing IMAX Theater.
Check our →schedule for show times.
Here is the solution:
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