How Old Is The Grand Canyon? Younger Than We Thought, New Research Suggests

By Josh Lieberman on January 27, 2014 11:24 AM EST

The Grand Canyon is 6 million years old, study suggests
The Grand Canyon is only about six million years old, according to new research. Those in the "older canyon" camp believe that the Grand Canyon was formed as much as 70 million years ago. (Photo: Reuters)

The Grand Canyon is six million years old, scientists say. The Grand Canyon is 70 million years old, other scientists say. Who's right, and why is it so hard to tell?

In a study published journal Nature Geoscience, a team led by Karl Karlstrom of the University of New Mexico says that the Grand Canyon is both very old and a little less old. They suggest that about six million years ago, the Colorado River began flowing through the two-billion-year-old rocks that make up the canyon walls. The team does believe that sections of the Grand Canyon may be tens of millions years old, but not the entire thing, as those in the "old canyon" camp believe.

Like Us on Facebook

"I think we've resolved the 140-year-long debate about the age of the Grand Canyon," Karlstrom told Nature. "We're making a major leap from thinking of a canyon that has a simple history...to a more sophisticated understanding of how landscapes actually evolve through time," he told NPR.

The difficulty in determining the Grand Canyon's age stems from the fact that rivers, by their very nature, carry evidence away from geologists. Erosion makes the rock record disappear, so geologists are left looking at a lack of something--not exactly ideal when you're trying to gather evidence, says Karlstrom.

Karlstrom and his team used thermochronology to analyze how the canyon walls' temperature varies layer by layer. The temperature of rocks increases the further down into the earth's crust it goes, so determining the temperature of each rock layer over time of rock can tell scientists when the layers were formed and when they eroded. 

Karlstrom and co. took samples of rocks from four of the Grand Canyon's major sections, both at river level and at the mile-high canyon rim, and looked at apatite in the samples. In this mineral, the radioactive breakdown of uranium creates helium, which arrays itself in a specific way according to the temperature of the rock. By looking at this helium distribution in various sections of the Grand Canyon, the team could determine the rocks' ages. They found that two segments in the middle of the canyon were 15 to 25 million years old, while a section further downriver was 50 to 70 million years old. 

"Different segments of the canyon have different histories and different ages, but they didn't get linked together to form the Grand Canyon with the Colorado River running through it until five to six million years ago," said Karlstrom.

The study won't be settling the old canyon vs. young debate anytime soon, though. Rebecca Flowers, author a 2012 study estimating that the Grand Canyon is 70 million years old, said: "It will take a bit more time to understand fully why their interpretations are so different from ours." Brian Wernicke, a Caltetch geologist and member of the old canyon camp, was more blunt: "That just hit me like a ton of bricks," he said of Karlstrom's conclusions. "They're not thinking this through."

READ MORE:

One-Quarter Of The World's Sharks And Rays Are At Risk Of Extinction, IUCN Study Finds

Fungi Explain Rainforest Diversity, "Police" The Growth And Spread Of Dominant Species

River Dolphin Discovered In Brazil Marks The First New River Species Since 1918; Sadly, It's Already Endangered

© 2012 iScience Times All rights reserved. Do not reproduce without permission.

Join the Conversation

Sponsored From Around the Web

    ZergNet
Follow iScience Times
us on facebook RSS
 
us on google
 
Most Popular
INSIDE iScience Times
Do Dolphins Get High? BBC Cameras Catch Dolphins Chewing On Pufferfish Toxins
Do Dolphins Get High? BBC Cameras Catch Dolphins Chewing On Pufferfish Toxins
How Many Ways Can You Tie A Tie?
How Many Ways Can You Tie A Tie?
Ribbon Of Charged Particles At Solar System's Edge Acts Like A Wind Sock For Interstellar Magnetism
Ribbon Of Charged Particles At Solar System's Edge Acts Like A Wind Sock For Interstellar Magnetism
How to Turn Your Tap Water Faucet  Into a Coffee Spout [VIDEO]
How to Turn Your Tap Water Faucet Into a Coffee Spout [VIDEO]
Coolest Science Photos Of 2013: From Blobfish To Two-Headed Shark, Comet ISON To Mars Selfie
Coolest Science Photos Of 2013: From Blobfish To Two-Headed Shark, Comet ISON To Mars Selfie
This Is A Scientifically-Proven Rock-Paper-Scissors Winning Strategy (But If Your Opponent Uses It Too, It's A Draw)
This Is A Scientifically-Proven Rock-Paper-Scissors Winning Strategy (But If Your Opponent Uses It Too, It's A Draw)