JOIN USProfessor Alan Levander, of Rice University, has discovered a giant structure deep beneath the Colorado Plateau which could explain how the Grand Canyon was created.
He said magma in a layer of the earth's crust is forcing the top layer and surging up to take its place, pushing up the land around the valley which forms the canyon,
'The Daily Mail' reported.
"Anyone who goes to the Grand Canyon and looks down should think,"What is it that made it this way?" Levander told LiveScience
"The most immediate answer is water, that a river cut this canyon, but what is it that made the rock it lies in, the earth, move up?"
Scientists have long been puzzled as to how the tectonically-stable plateau could be rising while parts of its lower crust are falling, a phenomenon more usually seen in mountain belts.
Levander and a team of geologists analysed new data from the mobile seismic stations known as the Earthscope Transportable Array
The observatory-quality seismographs were first set up in the West in 2004, and are moving across America in a ten-year project.
Images taken from the stations revealed that an unusually cold, dense region more than 120 miles deep stretching into the second layer of the earth's crust.
In a paper published in Nature, Levander described how he believes that the anomalous structure is caused by an upsurge in magma from a lower layer, which causes the crust itself to peel off.
He believes the hotter, weaker athenosphere surged upwards and invaded the stronger lithosphere above it, which includes both the uppermost crust and the top layer of the mantle.
The partially-molten material expanded, cooled and solidified after it flowed upwards, putting more weight on the mantle-section of the lithosphere.
This became so heavy it then peeled away and dripped down, creating a space
above it.
The more buoyant asthenosphere filled the gap, expanded again and caused the entire plateau to uplift, according to LiveScience.
Levander's believes this 'mantle drip' happened in the last six million years, making it the most recent anomaly in the Colorado Plateau, a finding which could help pinpoint the age of the Grand Canyon.
He told Amazing Planet, "There are generally two schools of thought on the age of the Grand Canyon - one is that it formed in the last six million or seven million years, and the other is that it has a much longer history as a canyon.
Our results suggest it's the younger date that's more accurate."
Grand Canyon is a steep-sided canyon carved by the Colorado River in USA's Arizona state.