Coconino Sandstone
Encyclopedia
Coconino Sandstone is a geologic formation named after its exposure in Coconino County, Arizona
Coconino County, Arizona
-2010:Whereas according to the 2010 U.S. Census Bureau:*61.7% White*1.2% Black*27.3% Native American*1.4% Asian*0.1% Native Hawaiian or Pacific Islander*3.1% Two or more races*5.2% Other races*13.5% Hispanic or Latino -2000:...

. This formation spreads across the Colorado Plateau
Colorado Plateau
The Colorado Plateau, also called the Colorado Plateau Province, is a physiographic region of the Intermontane Plateaus, roughly centered on the Four Corners region of the southwestern United States. The province covers an area of 337,000 km2 within western Colorado, northwestern New Mexico,...

 province of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

, including northern Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...

, northwest Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...

, Nevada
Nevada
Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...

, and Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...

.

This rock formation is particularly prominent in southeastern Utah, where it can be seen in a number of national parks and monuments, including Zion National Park
Zion National Park
Zion National Park is located in the Southwestern United States, near Springdale, Utah. A prominent feature of the park is Zion Canyon, which is 15 miles long and up to half a mile deep, cut through the reddish and tan-colored Navajo Sandstone by the North Fork of the Virgin River...

, Capitol Reef National Park
Capitol Reef National Park
Capitol Reef National Park is a United States National Park, in south-central Utah. It is 100 miles long but fairly narrow. The park, established in 1971, preserves 378 mi² and is open all year, although May through September are the most popular months.Called "Wayne Wonderland" in the 1920s...

, the San Rafael Swell
San Rafael Swell
The San Rafael Swell is a large geologic feature located in south-central Utah, USA about 30 miles west of Green River, Utah. The San Rafael Swell, approximately by , consists of a giant dome-shaped anticline of sandstone, shale, and limestone that was pushed up during the Paleocene Laramide...

, and Canyonlands National Park
Canyonlands National Park
Canyonlands National Park is a U.S. National Park located in southeastern Utah near the town of Moab and preserves a colorful landscape eroded into countless canyons, mesas and buttes by the Colorado River, the Green River, and their respective tributaries. The park is divided into four districts:...

. It is also present in the Grand Canyon
Grand Canyon
The Grand Canyon is a steep-sided canyon carved by the Colorado River in the United States in the state of Arizona. It is largely contained within the Grand Canyon National Park, the 15th national park in the United States...

, where it is visible as a prominent white cliff forming layer. The thickness of the formation varies due to regional structural features, in the Grand Canyon area it is only 65 ft thick in the west, thickens to over 600 ft in the middle and then thins to 57 ft in the east. Either the Kaibab Limestone
Kaibab Limestone
The Kaibab is a geologic formation that is spread across the U.S. states of northern Arizona, southern Utah, east central Nevada and southeast California. This geologic unit is part of the Park City Group in Nevada and Utah and is sometimes locally classified as a geologic group in Utah...

 or Toroweap Formation overlies the Coconino Sandstone. The Coconino Sandstone is typically buff to white in color. It consists primarily of fine well sorted quartz grains, with minor amounts of potassium feldspar grains deposited by eolian processes
Eolian processes
Aeolian processes pertain to the activity of the winds and more specifically, to the winds' ability to shape the surface of the Earth and other planets. Winds may erode, transport, and deposit materials, and are effective agents in regions with sparse vegetation and a large supply of...

 (wind-deposited) approximately 260 million years ago. Several structural features such as ripple marks
Ripple marks
In geology, ripple marks are sedimentary structures and indicate agitation by water or wind.- Defining ripple cross-laminae and asymmetric ripples :...

, sand dune deposits, rain patches, slump marks, and fossil tracks are not only well preserved within the formation but, they also contribute evidence of its eolian origin.

Lechatelierite
Lechatelierite
Lechatelierite is silica glass, amorphous SiO2. One common way in which lechatelierite forms naturally is by very high temperature melting of quartz sand during a lightning strike...

 was formed during the impact of a meteorite
Meteorite
A meteorite is a natural object originating in outer space that survives impact with the Earth's surface. Meteorites can be big or small. Most meteorites derive from small astronomical objects called meteoroids, but they are also sometimes produced by impacts of asteroids...

 into a layer of Coconino Sandstone at Meteor Crater
Meteor Crater
Meteor Crater is a meteorite impact crater located approximately east of Flagstaff, near Winslow in the northern Arizona desert of the United States. Because the US Department of the Interior Division of Names commonly recognizes names of natural features derived from the nearest post office, the...

 in Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...

.

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