We finally know how a fault that gave rise to Denali, North America's highest mountain, first formed. According to new research, the Denali Fault is actually an ancient suture mark where two land masses once joined together. Between 72 million and 56 million years ago, an oceanic plate called the Wrangellia Composite Terrane bumped into the western edge of North America and stuck there.
"Our understanding of lithospheric growth, or plate growth, along the western margin in North America is becoming clearer," Sean Regan , a geoscientist at the University of Alaska, Fairbanks and the lead author of a paper published in October in the journal Geology detailing the fault's history, said in a statement . Massive fault The Denali Fault is a strike-slip fault, a place where two chunks of continental crust slide past each other. On Nov.
3, 2002, the fault jolted, creating a magnitude 7.9 earthquake that knocked houseboats off their moorings more than 1,500 miles (2,414 kilometers) away in Seattle, according to an article in NASA's Earth Observatory blog. Regan studied three sections of the fault: The Clearwater Mountains of southeastern Alaska, Kluane Lake in Canada's Yukon Territory, and the Coast Mountains near Juneau.
These sites are hundreds of miles apart along the faultline. The sites are spread across about 620 miles (998 kilometers). Research in the 1990s had suggested that despite this distance, these three fault sections were formed at the same time and place, only to be to.