A trip out to Red Rock Canyon can be thoroughly interesting and educational as well. Students will learn first hand about geology and earth science as they witness the magnificent rock and land transformations.
From Ancient Seabed to Arid Desert:
For most of its 600-million-year geologic history, the presently arid desert of Red Rock Canyon National Conservation Area lay beneath a warm, shallow sea that was home to a rich variety of marine life. When small sea creatures died and settled to the bottom, the calcium in their bodies, together with the carbonate minerals from the sea, formed thick deposits which resulted in the limestone and dolomites we see today.
About 180 million years ago, Red Rock became increasingly arid, buried not by water but by windblown sand. Massive Sahara-like dunes stretched for hundreds of miles, sometimes several thousand feet deep. Most sediments at Red Rock Canyon are deposited horizontally. Sand piled high in dunes, however, forms inclined layers that change direction according to the vagaries of the shifting winds. Red Rock’s Calico Hills are a stunning example of such cross-bedded sandstone.
Cemented into rock by the interaction of iron oxide and calcium carbonate with water, evidence of similar dunes can be found in the brightly colored red and white cliffs and rounded hummocks of Nevada’s Valley of Fire State Park and Zion National Park in Utah.
Red Rock Canyon’s Aztec Sandstone is the westernmost extension of the Navajo Sandstone of the Colorado Plateau. It forms a bold and conspicuous cliff along part of the eastern flank of the Spring Mountains – an escarpment 20 miles long and nearly 3,000 feet high. These “fossil” sand dunes typically weather into abstract forms. As with the Chinle, true fossils are scarce to non-existent.
The alternating hues of red, yellow, and white displayed by the Aztec are believed to result from groundwater percolating through the sand and leaching out oxidized iron. Distinct color shifts may be caused by abrupt changes in porosity and permeability, though scientific debate continues.
Littering the base of many sandstone rocks are “Indian marbles.” These intriguing spheres form rather like pearls in oysters: an iron grain or other point becomes surrounded by concentric layered deposits. The balls, cemented by the iron resist erosion but eventually fall to the ground as the softer surrounding rock material is weathered away.
The Mesozoic Era was also marked by volcanic activity. Ash spewed out of volcanoes or cinder cones occurs within some of the sandstones in Red Rock. The forces of erosion through the centuries, acting on rock laid down in different epochs, have created a variety of shapes and features to amaze visitors.
Students can observe the strata and sandstone creations from a car window on the drive around Red Rock Canyon. However, hiking, bike riding, or walking along the various park paths will allow students, parents, and visitors to observe the natural beauty of the canyon in a much more personal way.
Enjoy this fascinating day trip to Red Rock Canyon National Conservation Area!
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See also CJ Hatcher’s National Lesson Plans column!