The vast area of exposure of these formations in the cliffs and canyons of Zion provides an important resource for ongoing investigations of the paleontology of the St. Dozens of new dinosaur tracksites have been discovered in the Whitmore Point Member of the Moenave Formation, the Kayenta Formation, and the Navajo Sandstone. Terrestrial vertebrate body fossils, including the remains of phytosaurs, aetosaurs, and metoposaurs have been found in the Shinarump and Petrified Forest Members of the Chinle Formation. We have identified over 100 new sites as a result of this project. In cooperation with the Utah Geological Survey, several National Park Service interns have recently completed a comprehensive inventory of paleontological resources within the park. The spectacular rocks exposed in Zion National Park in southwestern Utah include fossiliferous units of Late Triassic and Early Jurassic age. Hurricane fault zone, and represents the Western margin of Pangea. The Moenkopi Formation is exposed in fault-bounded blocks along the The Kolob Canyons lie 35 miles north of St. The Moenkopi Formation is Early Triassic in age (248 my-Ģ42 my) and is exposed in several areas of Zion National Park including the Kolob Canyons District, which lies in Range physiographic provinces in the Western U.S. Western margin of the Colorado Plateau, near the transition zone between the Colorado Plateau and the Basin and Regionally, Zion National Park lies at the The earliest Mesozoic vertebrate footprint locality in North America. The extensive exposures of thisįormation in the cliffs of the Kolob Canyons provide important information about the early Triassic and contain Utah include fossiliferous units of the Early Triassic Moenkopi Formation. The spectacular rocks exposed in the Kolob Canyons District of Zion National Park in southwestern Recent uplift to its present high-desert elevation has caused aggressive incision by the Colorado and Green Rivers and their many tributaries, forming a unique combination of beauty, isolation, and geologic history.
The recreation area has literally had its “ups and downs.” The tectonic history of the area is recorded in the stratigraphy and consists of several episodes of subsidence and deposition alternating with periods of uplift and erosion. Active surficial processes continue to shape the recreation area, such as large landslides and rock falls involving the Triassic Chinle Formation and Triassic-Jurassic Wingate Sandstone. Glen Canyon National Recreation Area also contains a surprising variety of unconsolidated surficial deposits that provide clues to the age of the canyons. The bedrock units range in age from Late Pennsylvanian (300 million years ago) to Late Cretaceous (about 85 million years ago), and record a fascinating history of deposition in shallow seas, tidal flats, sabkhas, vast alluvial plains, and enormous sand dune-covered deserts dotted with oases. The recreation area is dominated by sparsely vegetated, spectacularly exposed layers of classic Colorado Plateau rocks. The canyons in the recreation area formed within the past 5 million years (much within the last one million years) by vigorous downcutting of the Colorado River and its tributaries to expose more than 10,000 feet of bedrock that spans about 300 million years. It includes the shores of Lake Powell-the reservoir behind Glen Canyon Dam-and parts of other main drainages of the Colorado River including the Green, Dirty Devil, Escalante, and San Juan Rivers. The recreation area is located in southeastern Utah and in a small part of northern Arizona. Glen Canyon National Recreation Area contains some of the best examples of the spectacular and unique geology that the Colorado Plateau has to offer.
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