How Old Is the Grand Canyon?

Redwall Caverns, eastern Grand Canyon i i

New research suggests that the formation of the Grand Canyon — when the first cuts began to form in the rock — began at least 17 million years ago. Victor Polyak hide caption

itoggle caption Victor Polyak
Redwall Caverns, eastern Grand Canyon

New research suggests that the formation of the Grand Canyon — when the first cuts began to form in the rock — began at least 17 million years ago.

Victor Polyak
Caves in the Redwall Limestone in Marble Canyon, eastern Grand Canyon. i i

Scientists used features found in caves in the canyon's walls to try to determine the age of the Grand Canyon. Some geologists argue that the findings are unsound. Victor Polyak hide caption

itoggle caption Victor Polyak
Caves in the Redwall Limestone in Marble Canyon, eastern Grand Canyon.

Scientists used features found in caves in the canyon's walls to try to determine the age of the Grand Canyon. Some geologists argue that the findings are unsound.

Victor Polyak

Scientists know the age of the rocks at the Grand Canyon, but not the age of the canyon itself. Now, controversial new research suggests that the formation of the Grand Canyon began at least 17 million years ago, making the canyon significantly older than previously thought. The canyon channel is thought to have been completely cut through by 5 or 6 million years ago.

A group of scientists used features found in caves in the canyon's walls to try to put a date on the natural wonder. The researchers studied structures known as mammillaries or "cave clouds" — deposits that form at or near the water table level, and dated the features using uranium-lead isotope dating techniques.

The new study is controversial, with several geologists speaking out vocally about the study's methods and its findings. Victor Polyak, one of the scientists behind the new dating study, talks about the team's work and findings.

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