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The resulting Grand Canyon Supergroup of sedimentary units is composed of nine varied geologic formations that were laid down from 1.2 billion and 740 million years ago in this sea. [11] Good exposures of the supergroup can be seen in eastern Grand Canyon in the Inner Gorge and from Desert View, Lipan Point and Moran point. [12] [note 1]
The Grand Canyon [a] is a steep-sided canyon carved by the Colorado River in Arizona, United States.The Grand Canyon is 277 miles (446 km) long, up to 18 miles (29 km) wide and attains a depth of over a mile (6,093 feet or 1,857 meters).
In the Grand Canyon, the Tapeats Sandstone is a medium- to coarse-grained, thin-bedded, cliff-forming conglomeratic sandstone that weathers to a tan or reddish-brown. Its thickness varies from very thin or absent where deposited over prominent paleotopographic highs, as much as to 90 m (300 ft) high.
Geologic stratigraphic column of strata exposed in and near the Grand Canyon. The term Great Unconformity is frequently applied to the unconformity observed by John Wesley Powell in the Grand Canyon in 1869. [1] It is an exceptional example of relatively young sedimentary rock strata overlying much older sedimentary or crystalline strata.
The Mesoproterozoic formations in the Grand Canyon are overlain by the 850 million year old, Neoproterozoic Chuar Group and Sixtymile Formation sedimentary rocks. The Great Unconformity is a famous gap in the stratigraphic record of the Grand Canyon of 900 million years between Proterozoic granitic rocks and Cambrian marine sediments. For the ...
The Grand Canyon, Arizona, at the confluence of the Colorado River and Little Colorado River.. A canyon (from Spanish: cañón; archaic British English spelling: cañon), [1] gorge or chasm, is a deep cleft between escarpments or cliffs resulting from weathering and the erosive activity of a river over geologic time scales. [2]
The thickest known section of Surprise Canyon Formation is exposed in Quartermaster Canyon in western Grand Canyon, where the formation is about 122 m (400 ft) thick. In the central Grand Canyon outcrops of the Surprise Canyon Formation are up to 45 m (148 ft) thick, whereas in eastern Grand Canyon and Marble Canyon region such outcrops are 18 ...
The Grand Canyon Supergroup is a Mesoproterozoic to a Neoproterozoic sequence of sedimentary strata, partially exposed in the eastern Grand Canyon of Arizona. This group comprises the Unkar Group , Nankoweap Formation , Chuar Group and the Sixtymile Formation , which overlie Vishnu Basement Rocks .