Britannica Sources used in this answer

How did faulting help form the Tetons of Wyoming?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

A car drives along the Trans-Canada Highway with Mount Sir Donald's sharp, snow-capped peak rising above forested slopes in the Selkirk Mountains, British Columbia. — mountain Mount Sir Donald in the Selkirk Mountains, British Columbia, looms above a segment of the Trans-Canada Highway.

The Teton Range was formed through a process of crustal movement known as block-faulting. Beginning approximately six million years ago, a massive block of the Earth's crust was uplifted to create the mountains, while a corresponding adjacent block subsided to form the valley known as Jackson Hole.1

This geological activity created a distinct fault line along the eastern base of the range, causing the mountains to rise abruptly in the east while sloping more gradually toward the west. As a result of this tectonic displacement, the peaks of the Teton Range now tower more than 7,000 feet (2,130 meters) above the valley floor. Over subsequent millennia, the rugged topography created by this uplift was further sculpted by glaciers, which carved deep, U-shaped canyons into the mountains and deposited rock debris in the valley below.12