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Capitol Reef National Park

National Park Service U.S. Department of the Interior “Geology knows no such word as forever.” —Wallace Stegner Capitol Reef National Park’s geologic story reveals a nearly complete set of Mesozoic-era sedimentary layers. For 200 million , layers formed at or near sea level. About 75-35 million years ago tectonic forces uplifted them, forming the Waterpocket . Forces of have been sculpting this spectacular landscape ever since.

Deposition If you could travel in time and visit Capitol Visiting Capitol Reef 180 million years ago, Reef 245 million years ago, you would not when the Navajo was deposited, recognize the landscape. Imagine a coastal you would have been surrounded by a giant park, with beaches and tidal flats; the water sand sea, the largest in Earth’s history. In this moves in and out gently, shaping hot, dry climate, wind blew over sand dunes, in the wet sand. This is the environment creating large, sweeping crossbeds now in which the of the Moenkopi preserved in the sandstone of Capitol Formation were deposited. and Fern’s Nipple.

Now jump ahead 20 million years, to 225 All the layers were laid million years ago. The tidal flats are gone and down at or near sea level. Younger layers were the climate supports a tropical jungle, filled deposited on top of older layers. The Moenkopi with swamps, primitive trees, and giant ferns. is the oldest layer visible from the visitor center, The water is stagnant and a humid breeze with the younger above it. brushes your face. Oxygen-rich river water is ; the Kayenta oxidized the iron in the sediments, giving the Formation that formerly capped it has eroded Chinle Formation its lavender and red colors, away, but is still visible atop the red cliffs behind while the reducing environment of stagnant it. White domes of comprise bogs gave it the greens and grays. the highest and youngest layer seen from the visitor center.

Uplift The movement of, and the interaction area of otherwise nearly horizontal layers. between, Earth’s tectonic plates created the The layers on the west side of the Fold have different environments in which Capitol been lifted more than 7,000 feet (2134 m) Reef’s nineteen rock layers were formed. Few higher than corresponding layers on the east. of these sedimentary layers would be visible, The is the longest exposed however, if not for the Laramide , a monocline in and is nearly 90 massive building event that likely miles in length. It is the main reason Capitol reactivated an ancient buried between Reef National Monument was established in 75 and 35 million years ago. The compression 1937. associated with the Laramide Orogeny gave rise to a one-sided fold, or monocline, in the The folding and tilting of the rock layers allow earth’s crust within the . you to travel through 280 million years of Capitol Reef’s geologic history in just fifteen The Waterpocket Fold is a classic monocline: miles by driving through the park on State an enlongated fold with one steep side in an Route 24.

Erosion Capitol Reef’s spectacular scenery reflects role. Flash floods are the most dramatic not only the underlying structure of the display of erosion in action. Floodwaters Waterpocket Fold, but also the differing propel debris, , cobbles, and degrees of resistance to and boulders, increasing water’s carving power. erosion seen in each rock layer. Deposition and uplift in Capitol Reef have Water is the dominant erosional force in created a unique into Earth’s history, Capitol Reef, with wind playing only a minor revealed through the power of erosion.

Cenozoic andesite

Navajo Sandstone and Wingate Sandstone

Sandstone Deeply-buried fault publications on Capitol natural and Reef’s cultural history. to Capitol links the also which Natural Reef History Association, anon-pro t cooperating association that sells Additional information of on Capitol geology the National Reef Park is available on our website (www.nps.gov/care) Paleo- Thickness Rock Type Location / Remarks Landforms Age Capitol Reef Column environment 65 MYA Tarantula Mesa Sandstone 1200-1450 feet Floodplains, coastal areas, West side of Henry Mtns., interlayered with sandstone Masuk Formation (combined) and marine east of Strike Muley Canyon Sandstone

Mostly dark gray shale interlayered Shallow sea that bisected Factory and near 2000-3000 feet with sandstone North America Caineville 0-50 feet Tan sandstone, oyster shell Coastal Oyster Shell Reef; locally absent DakotaDakota Sandstone Sandstone

EXPERIENCE YOUR AMERICA™ North and east of the Hartnet Road 0-100 feet and mudstone layers Rivers and Floodplains Cedar river ford 144 MYA White crossbedded sandstone (Salt Vast river systems; Brushy Basin Member Bentonite Hills; along Notom-Bullfrog Morrison 180-700 feet Wash) & candy-striped mudstone bentonite clays from Road north of Burr Trail Formation Salt Wash Member (Brushy Basin) altered volcanic ash Thinly-bedded, reddish ; 150-300 feet Tidal fl ats Cliffs at east park entrance thick, wavy gypsum on top

0-80 feet Grayish-green sandstone & siltstone Marine Caps cathedrals of Cathedral Valley

Earthy, red, very fi ne-grained Transition between tidal 450-750 feet Cathedrals of Cathedral Valley sandstone & gypsum fl ats and dune fi elds

Interlayered red sandstone, Shallow marine, tidal fl ats, Forms red V-shaped chevrons on 300-100 feet siltstone, & gypsum & (sandy salt fl ats) east side of Waterpocket Fold 50-100 feet Tan sandstone Sand dunes Cap of Page Sandstone

Capitol Dome, Navajo Dome, & Navajo Sandstone 800-1100 feet White crossbedded sandstone Vast region of sand dunes Grand Wash Narrows

Interlayered white sandstone & red Top, ledgy portion of Fruita Cliffs; 350 feet West-fl owing rivers Kayenta Formation siltstone Hickman Bridge

350 feet Sandstone, often stained dark red Sand dunes Fruita Cliffs & Circle Cliffs Wingate Sandstone

206 MYA Interlayered sandstone, siltstone, & Forested basin with rivers, Slopes below Fruita Cliffs; contains 350-550 feet Shinarump Chinle Formation bentonitic mudstone swamps, & petrifi ed wood & uranium Member www.nps.gov/care 0-90 feet White sandstone River channels Discontinuous; cap of Mostly dark red siltstone & Gently sloping coastal Miners Mountain, Egyptian Temple, 500-1000 feet mudstone; minor yellowish , fl uctuating sea level & base of Chimney Rock 248 MYA 70-100 feet Gray dolomitic limestone Marine Gorge

Fremont River Gorge & 400+ feet White crossbedded sandstone Beach & dune sands White Rim Sandstone Goosenecks of Sulphur Creek

11/15 290 MYA MYA = Million Years Ago