Grand Canyon Narrative

Some of the students in Mr. McGregor’s science class were giving reports on where they had been during summer vacation. Alice brought a book about the Grand Canyon and some pictures she had taken of the canyon. She said the layers of rocks seen in the canyon had taken millions of years to form. Then it had taken millions of more years for the Colorado River to erode the Grand Canyon down to the oldest kind of rocks on earth. She pointed to a layer of sandstone and said these rocks used to be part of a large desert.

Joey wanted to know how Alice was so sure about how old these places were.

“It says so right here,” she replied, holding up her book. “They wouldn’t put it in here if it wasn’t true.”

“How do they know the sandstone rocks used to be a desert?” Joey asked.

“Because it says so right here,” Alice repeated firmly.

Joey couldn’t wait to talk with his father after school. Dr. Houston taught chemistry at the University, but he knew a lot about geology and methods of dating rocks.

“Hey, Dad, did there used to be a desert in the middle of the Grand Canyon and how old is the Grand Canyon?”

Joey got right to the point before he told his dad about Alice and her book.

“Although most geologists believe it took millions of years for the Grand Canyon to form, trying to reconstruct what happened in the past can be tricky.”

“Why is that?” Joey asked.

“OK, pay attention or you’ll get lost in some big words and the math,” his dad smiled. “You have to look at the age of the canyon in two ways--how long it took for the layers of rock to form and how long it took for the canyon to be eroded. First of all, the geologists who wrote Alice’s book assumed that most of the horizontal layers of rocks in the Grand Canyon were deposited from an ancient ocean that may have dried up from time to time. They also assume the rate at which sedimentation occurs in the oceans today is the same as the rate that occurred in the past. Are you with me?” Dr. Houston asked.

“So far,” Joey said.

“The present rate of sediment formation in the deep oceans is estimated to be between 1 and 10 cm every 1000 years. The rate is so small it is difficult to measure. Even though there is a lot of sediment deposited at the mouth of rivers and along the continental shelf, not much new sediment is being deposited in the deep ocean plains today. Now think. Geologist might make a rough estimation of the age of the sedimentary layers of rocks from the thickness of the layers in the canyon by assuming that the sedimentation rate has always stayed about the same. The layers of rock in places are 1200 meters thick, which is 120,000 cm. If it took 1000 years for just a few centimeters to form, it would have taken many millions of years for the sedimentary layers of rock to form.”

“I guess so.” 

“But if the rate of sedimentation had been many times faster in the past than it is now, how accurate would the estimated ages be?”

“That would mean the real age for the canyon would be different from what is in Alice’s book,” Joey smiled confidently this time.

“You’re exactly right. Now, suppose there was not an ocean over the canyon area. Instead, there was a gigantic flood that covered the whole area. The force of the moving water would have loosened and moved large amounts of the land. Some of this material would have been suspended in the water for a time, but it would have quickly settled out as the water became calmer. How fast the sediment settled out of the water would be much greater than the slow rate of sedimentation in the deep oceans today. The hardening of the rock would also be rapid because there would have been chemicals in the water that caused the sediment particles to be cemented together.”

“That much makes sense, but what about the desert in the middle of the Grand Canyon,” Joey asked. “How could there be a giant flood and a desert in the same place at the same time?”

That’s easy,” Dr. Houston replied. “At first, the cross beds in the sandstone looked like they had formed from desert sand dunes to some of the researchers. Further research showed that underwater currents could cause the sand to form shapes that resemble desert sand dunes. There are also hundreds of fossilized amphibian or lizard footprints in the sandstone rocks that provide good clues. One researcher studied footprints of newts and salamanders that are able to walk either on land or under water. He found the footprints made by newts walking under water looked much more like the fossil footprints than the footprints made in desert sand.”

“Do scientists believe all the other rock layers in the canyon were laid down by water?” Joey asked.

“Yes, most do. Deposits from a large body of water is the most logical explanation for why flat level sedimentary layers are so widespread. The Canyon is 277 miles long and the same layers can be seen for most of this distance. Some of the layers are also found in other canyons hundreds of miles away. The long flat layers might have been deposited by deltas, rivers, flood plains, or beaches, but they probably wouldn’t have produced flat layers over such a large area.”   

“Are there sedimentary layers of rock under the ground all over the world?” Joey asked.

“Yes, they are found in practically every country on earth, but the ones that are below ground are not always visible. One of the amazing things about Grand Canyon is that we can see what’s below the ground for a very long distance. The horizontal layers are visible all the way down to something called the Great Unconformity, where widespread erosion occurred between the rocks above and below it. Below that are some tilted layers of rock and a very hard crystalline basement rock. There is an abundance of fossils above the Great Unconformity, but fossils are rare below it. The rocks below the Great Unconformity are called Precambrian. Let me show you a book I have about the Grand Canyon.

Here’s a diagram of what you see at the Grand Canyon.

Grand Canyon Grand Canyon
I. Diagram of rock layers that can be seen in the Canyon.
The distance from the Canyon rim to the bottom of the
Canyon is over a mile in many places.
Click to enlarge Image

The writers of Alice’s book believe the layers formed slowly over millions and millions of years. However, I find it logical to conclude that all the horizontal sedimentary layers of rock above the Great Unconformity were deposited from a large body of water containing a large amount of sediment. I also think the layers could have been deposited in a short period of time.”

“That makes sense to me too,” Joey added, “but Alice would probably throw her book at me if I told her that.”

“You may be right,” Dr. Houston laughed. She seems to put a lot of faith in her book. But here’s something else to think about. Some geologists believe that millions of years passed in between some of the layers. During that time, there would have been a great deal of erosion. If that is true, I don’t think the canyon would look like it does now. It would probably look more like this.” Dr. Houston turned to another page to show Joey what he was talking about. 

Grand Canyon

II. Diagram of rock layers showing a proposed gap between two existing
flat layers. The lack of gullies, canyons, and valleys in the landscape over
such a long period is doubtful. Rather, the layers appear to have been
laid down before erosion could have occured between them.

“Erosion doesn’t wear the ground down evenly. Gullies are bound to form during long periods of time, along with faults, folding of layers, and other geologic changes. Even though all of these features are seen in a few places in the Canyon, the most striking features are the long continuous flat layers. It seems as if each new layer of sediment was added to the one below it before gullies and other kinds of erosion had a chance to form.”

“But what about dating of the canyon layers with radioactive elements?” Joey asked.

“It is difficult to do radiometric dating on sedimentary rocks, but there are a few places in the canyon where there have been lava flows that hardened into rocks. Theoretically, radiometric dating can be used to date volcanic rocks. But there are problems. (1) Scientists have obtained widely different results as they tested the same kind of rocks with different tests. (2) Some lava flows have a known age of less than a few hundred years. When dated by radiometric dating, they gave ages of millions of years. I find this evidence very inconclusive.”

“Some geologists accept the explanations in Alice’s book that the sedimentary layers formed over millions of years. But, other geologists believe the Canyon’s rock layers formed rapidly as a result of a massive flood. Are you ready to hear some explanations for how the Canyon was eroded?”

“Sure.” Joey found this conversation with his dad completely fascinating.

“We know the sedimentary layers on the eastern end of the Canyon were pushed up by underground forces at some time. One theory is that part of the raised up land blocked the normal drainage of water from the east. The raised up land would have been a boundary wall for one or more very large lakes that formed sometime after a period of flooding. They may have been like the Great Salt Lake in Utah with no way for the water to drain into the ocean. This is how the lakes may have looked,” Dr. Houston continued as he found another page in his book.

Grand Canyon
III. Diagram of locations of three former lakes that may have breached their dams and emptied their waters into the present Grand Canyon.

“The amount of water in the lakes has been estimated to be about three times as much as the water found in Lake Michigan. All of this water may have broken through weak places in the wall, one lake at a time. Once little openings in the wall formed, they quickly became large openings, allowing tons of water to push out of each of the lakes with great force. All the water would have eventually rushed through the same area, making the canyon deeper and wider as long as the water continued to flow. This is known as the Breached Dam Theory. Most geologists today think this is probably what happened.”

“Did it take a long time for the canyon to get so deep and wide?”

“It’s hard for us to imagine how quickly a large amount of rushing water or mud can erode even through hard ground. Did you know there were a group of canyons over 100 feet deep that formed north of Mount St. Helens beginning on March 19, 1982, with a huge mudflow? Some of the canyons formed through piles of recent debris and some formed in hard ground. Much of the Grand Canyon could also have been eroded within a very short period of time from similar processes.”

“I think the thick sedimentary layers in the Canyon and the water that got trapped in the lakes are a result of the flood we read about in Genesis. Right, Dad?” Joey asked. Then he paused and added, “Alice isn’t going to agree with this.”

“I think the Grand Canyon gives us a small picture of the how a worldwide flood shaped much of the earth’s geology,” Dr. Houston replied. “What I‘ve told you is logical, and you don’t have to apologize to Alice or anyone else for believing in a real Genesis Flood that covered the whole world. However, I expect you to be nice to Alice if you have another discussion about the Grand Canyon, even if she never agrees with you. Why don’t you and I talk about Flood Theory again later? I have some very interesting things to tell you about how a worldwide flood produced billions and billions of fossils and resulted in a long ice age, dramatic changes in the ocean levels, and other major changes in the world’s geology.”

“Thanks, Dad. I’d like to know more about the Flood. I promise to be nice to Alice, but I still want to show her MY book about the Grand Canyon.”

Explanations about both Darwinian evolution and the formation of geological formations are based on Hutton’s assumption that the present is the key to the past. Why are scientists like Dr. Houston not so sure this is a good assumption? What is an unconformity? Is there evidence of erosion between some of the sedimentary layers that are supposed to be millions of years apart? Read the following article and discuss it:




Creation Studies
Creation Studies Institute