Most of the sand, made of 98% translucent, rounded-grain quartz, was transported from coastal sand dunes to the west, in what is now central Nevada. For perhaps 10В million years sometime around 175В million years ago sand dunes accumulated, reaching their greatest thickness in the Zion Canyon area about 2,200В feet (670В m) at the Temple of Sinawava in Zion Canyon. WeatheringВ and erosion along north-trending faultsВ and fractures influence the formation of landscape features, such as canyons, in this region.ДЄpproximately 190 to 136В million years ago in the JurassicВ the Colorado Plateau areaвЂ™s climateВ increasingly became aridВ until 150,000В square miles (388,000В kmВІ) of western North AmericaВ became a huge desert, not unlike the modern Sahara. The plateau is bounded on the east by the Sevier Fault Zone, and on the west by the Hurricane Fault Zone. This means that the oldest strataВ are exposed along the Virgin River in the Zion Canyon part of the park, and the youngest are exposed in the Kolob Canyons section and moreso on the Makagunt Plateau to the north (Cedar Mountain). Zion National Park includes an elevated plateau that consists of sedimentaryВ formations that dip very gently to the east.

LavaВ flows and cinder conesВ covered parts of the area during the later part of this process. Zion Canyon was cut predominately by the North Fork of the Virgin River and its tributaries. The faster-moving streams took advantage of uplift-created joints in the rocks to cut gorges into the plateau. This steepened the stream gradientВ of the ancestral rivers and other streams on the plateau. Subsequent uplift of the Colorado Plateau slowly raised these formations much higher than where they were deposited (near & at sea-level).

The Navajo is part of a super-sequence of rock units called the Grand Staircase, the time exposed in the Zion and Kolob area were deposited in several different environments that range from the warm shallow seas of the Kaibab and Moenkopi formations, streamsВ and lakesВ of the Chinle, Moenave, and Kayenta formations to the large desertsВ of the Navajo and Temple Cap formations and dry near shore environments of the Carmel Formation. ZionвЂ™s formations represent about 150 million years of mostly Mesozoic-aged sedimentation in a large ancient Jurassic basin. View from Observation Point Trail of Zion National Park, UtahДЄlthough the geology of the Zion National ParkВ includes nine known exposed formations, Zion is predominately the result of one spectacular unit, the Navajo Sandstone.

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