The Waterpocket Fold: Two Hundred Million Years in One Drive

Capitol Reef National Park is organized around a single geological event that happened sixty-five million years ago. When the Colorado Plateau uplifted unevenly during the Laramide orogeny, the rock layers here flexed into a step-shaped fold called a monocline rather than breaking cleanly. That fold is one hundred miles long. You are driving through it now.

The Waterpocket Fold earned its name from the potholes in its surface: shallow depressions in the sandstone that collect and hold rainwater for weeks or months after a storm. In a desert where permanent water sources are separated by days of walking, these potholes made the landscape habitable. Fremont people farmed the Fremont River valley using them eight centuries before Mormon settlers arrived. The pockets are still there; you can see them in the rock faces along the scenic drive.

The fold is a cross-section of time made visible from your car window. At its base, Triassic mudstones laid down roughly two hundred twenty million years ago. At its top, Jurassic Navajo sandstone, the same deep-orange formation that makes the canyon walls of Zion, deposited approximately one hundred ninety-five million years ago. Nine distinct rock formations in between, each one a chapter in the plateau's long submersion under ancient seas, emergence, and re-burial.

Geologists call Capitol Reef the most complete and accessible display of Colorado Plateau stratigraphy anywhere on the surface. For everyone else, it is a hundred miles of canyon country where the roadcut itself is the exhibit.