Geology of Grand Canyon National Park
Grand Canyon National Park’s most impressive geological structure is quite obvious; the name says it all. But the Grand Canyon is not the only geology within the park. ... Located on the Colorado Plateau in northwestern Arizona, this amazing place was officially declared a National Park in 1919. But the geology of the 1,218,375-acre park has a much longer history. The peacefulness of the National Park does not hint at the massive amount of geological history that has taken place or the constant enlargement of the Grand Canyon. The first record of human discovery of the Grand Canyon dates back approximately 10,000 years to the Paleoindians. ... The age of the oldest layers of rock inside the Grand Canyon, which are comprised of Vishnu Schist and Zoroaster Granite, is somewhere between 1. ... As we have learned throughout our Physical Geology course, rock can be moved from one part of the Earth to another. ... Once the Colorado River was formed as the major drainage system for the Rockies, it probably traveled through Colorado beginning at Marble Canyon, which is in the northernmost portion of the Grand Canyon. ... The sediments deposited by the river laid the ground for the Grand Canyon. The “Grand Staircase” is a great way to understand how immense Grand Canyon National Park truly is. Although it extends hundreds of miles north of the Grand Canyon, it reaches a height of 11,311 feet. ... The layers of the canyon’s rim that have been eroded away can be found in the northern parts of the Grand Staircase, which will be explained further during the later discussion of The Great Unconformity. Erosion can be credited with a majority of the formation of the Grand Canyon itself. ... The Sun’s heat bakes the soil of Grand Canyon National Park, thus making it very hard and unable to absorb water. ... If pushed long enough or hard enough, pieces of the rock will eventually break off and cascade down the canyon, breaking off other pieces and piling up at the bottom. ... When the snow atop the Colorado Rockies melts, it floods the canyon and sweeps away the sediment deposited during flash floods. ... But this is no longer the case, due to the construction of the Glen Canyon Dam. Glen Canyon Dam was constructed “for the primary purpose of water storage to ensure delivery of water to the Lower Basin” (Glen Canyon Institute, 2003). ... The Colorado River and the Grand Canyon have been greatly affected since the Glen Canyon Dam was completed in 1963.