Lesson Plan - Get It!
At over 277 miles long, 6,000 feet deep, and 18 miles from rim to rim, there is no question the Grand Canyon is indeed very grand! However, the source of its origin continues to plague geologists, despite the vast collection of recent scientific data.
The question remains: Just how did the Grand Canyon become so grand?
It is important to know and understand that there are differing views on the age of the Grand Canyon and its origins.
Some scientists claim the Grand Canyon is millions of years old; others, who believe the earth to be much younger, contend the canyon is only thousands of years old.
Rather than give you the answer to the question, this lesson is designed to challenge you to compare and contrast the differing viewpoints, and think critically about them. In the process, you may find that you still have some unanswered questions, and that's okay! One thing all of the geologists agree on is there is much more to learn about the Grand Canyon!
Before moving on, if you overlooked or would like to review the previous Related Lessons on trees and radioactive dating in our Mysteries of Geology series, find them in the right-hand sidebar.
First, let's take a look at what old-Earth geologists have to say about the origins of the Grand Canyon.
One of the earliest scientists to attempt to explain how the Grand Canyon formed was John Wesley Powell. His theory was known as the antecedent river theory. This theory purported that geologic processes were creating an uplift in the Colorado Plateau at the same time and same rate as the Colorado River was eroding down into it. He arrived at his theory based upon his up-close and personal exploration of the Grand Canyon.
Read about John Wesley Powell's Grand Canyon Adventure, by Grand Canyon Adventures, Adventure Southwest LLC. Be sure to read the information detailing his expedition along the Colorado River in 1869.
While his observations were groundbreaking at the time, subsequent years of study and investigation would eventually rule out his theory about how the Grand Canyon was formed. Radioisotope dating (also called radiometric dating, The Free Dictionary) of the rocks along the rim of the canyon was one critical problem with Powell's idea.
Continue on to the Got It? section to further examine the evidence!