Beneath America's tallest mountain lies a secret: it stretches for 998 kilometers.

Scientists have finally uncovered how the fault that gave rise to North America's highest peak, Denali, was formed, reports LiveScience.

The latest research indicates that the Denali fault is an ancient seam where two land masses once joined together. Between 72 and 56 million years ago, an oceanic plate known as the Wrangellia terrain collided with the western edge of North America and became lodged there.

"We now have a better understanding of the growth of the lithosphere along the western edge of North America," says geologist Sean Regan from the University of Alaska Fairbanks and the lead author of the study.

He explains that the Denali fault is classified as a strike-slip fault, where two sections of the continental crust slide past one another. Back in 2002, this fault experienced a significant shake, resulting in a magnitude 7.9 earthquake.

In his research, Regan examined three locations along the fault: the Clearwater Mountains in southeast Alaska, Kluane Lake in Canada's Yukon Territory, and the Coast Mountains near Juneau. All three sites are located hundreds of kilometers apart along the entire fault line, stretching over an area of approximately 998 km.

Analysis revealed that despite the distance, all three segments of the fault formed at the same time and in the same location. They were later separated when the two sides of the fault slid against one another. However, until recently, this theory could not be confirmed.

To finally put an end to this story, Regan studied the mineral monazite at all three locations along the fault. This mineral contains rare earth elements that change as the rock surrounding it is altered by pressure or high temperatures. This is what allows geologists to decipher the history of the rock being studied.

The results indicate that these three regions were formed in the same place and at the same time. This location was the ultimate zone of the seam between the North American Plate and the Wrangell subplate, a mini-tectonic plate that is part of the complex puzzle of the northern Pacific coast.

As a reminder, scientists state that mountains on the planet form in various ways, with even erosion capable of lifting mountain peaks upward.