Scientists have long been debating about the actual age of the Grand Canyon. The canyon is part of the Colorado River basin, which is believed to have developed over 40 million years ago. While some experts believe that the beginnings of the Grand Canyon lie in a period of time around 17 million years ago, making accurate estimates about geological formations can be difficult due to the sheer number of forces that shape and mold the world we live in.
Older estimates place the number at around 70 million years ago. However, a recent study indicates that the canyon may have formed as late as 5 to 6 million years ago. While the theories are numerous and the estimates differ, a number of scientists now believe that the answer could lie somewhere in between. The recent study shows that different parts of the Grand Canyon may have in fact formed at different times throughout the Earth's long history.
The debate regarding the age of the Grand Canyon has been ongoing for the past century and a half. The new study, which was published in the online journal Nature Geoscience, involved researchers taking rock samples from different region of the 277-mile canyon. The researchers then dated the samples they took and analyzed the results. While analysis of the samples indicate that the Eastern Grand Canyon section and the Hurricane section, two of the central sections of the Grand Canyon, are much older, the two outer sections were formed more recently.
"The timing of formation of the Grand Canyon, USA, is vigorously debated. In one view, most of the canyon was carved by the Colorado River relatively recently, in the past 5-6 million years," says the research team in the published study. "Alternatively, the Grand Canyon could have been cut by precursor rivers in the same location and to within about 200 m of its modern depth as early as 70-55 million years ago."
Researchers have found that the Eastern Grand Canyon section is around 50 to 70 million years old. On the other hand, the Hurricane section has been found to be around 15 to 25 million years old. The date also hints that the newer sections of the Grand Canyon are around 5 to 7 million years old.
"Thus, although parts of the canyon are old, we conclude that the integration of the Colorado River through older palaeocanyons carved the Grand Canyon, beginning 5-6 million years ago," says the research team.
In what appears to be a compromise between two schools of thought, both "old" and "new" Grand Canyon theories may actually be correct.