Dakshina Marlier
Geology 111
Professor Yuengling
May 3, 2017
The Kayenta Formation
Rock Unit Description - (Part A) Copyright 2017 Salem State College
Above, the Kayenta layer is the significantly more stratified, slightly darker, and knobby layer seen second from the top, directly beneath the slick and sheer Navajo sandstone cliffs which, seen here, are forming fins on the Courthouse Towers in Arches National Park, Utah.
The Kayenta rock formation is a part of the Glen Canyon group found on the Colorado Plateau in northern Arizona, northwest Colorado, eastern Nevada, and Southern Utah, in the Southwestern United States. The
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When found together, these three formations can bring about gigantic vertical cliffs often greater than 2,000 feet (610 m). The Kayenta layer is generally pink, red, or dark brown, and often forms unstable benches.
When seen alongside the entire Glen Canyon Group, the Kayenta layer appears as a darker red, maroon, or light purple band of thin-bedded material between two thick, massive, cross-bedded layers of light brown, tan, or light-red color, which are the Wingate and Navajo Sandstones. Its weak layers often form a bench or platform by eroding the Navajo sandstone away from the face of the Wingate cliffs. The Kayenta is made up of layers of sandstone, shale, and limestone, uneven at their tops, and it does not generally extend over long distances because of its easily eroded
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The sedimentation usually visibly changes in going from the Wingate Sandstone formation to the Kayenta, and from the Kayenta to the Navajo sandstone, though in a few areas, the transition from Wingate to Kayenta is gradual, because the material in the Kayenta beds seems to have come from the Wingate immediately below it and re-deposited with the characteristics of fluvial sediments. Though the contact between the Kayenta and the Navajo in places is gradual in a few places, it far more often shows up as a thin, jumbled mass of sandstone and shales, chunks of shale and limestone, mud balls, and concretions of lime and iron, all lying at the base of the fine-grained, cross-bedded Navajo Sandstone.
Mud cracks, a few ripple marks, and drainage channels can be found in the topmost section of the Kayenta found on Red Rock Plateau in San Juan County, Utah at an elevation of around 4,163 ft. above sea level, as well as in Grand Canyon West where wide sand-filled cracks appear in it. These features may show that, in places at least, the Wingate and Kayenta eroded before the geologic formations above were deposited, and this may explain why there can be a wide range of thicknesses in the Kayenta Formation. The small, black arrow in