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62-433: The Navajo Sandstone is particularly prominent in southern Utah, where it forms the main attractions of a number of national parks and monuments including Red Rock Canyon National Conservation Area , Zion National Park , Capitol Reef National Park , Glen Canyon National Recreation Area , Grand Staircase–Escalante National Monument , and Canyonlands National Park . Navajo Sandstone frequently overlies and interfingers with

124-480: A thin section using a method like the Gazzi-Dickinson Method . This yields the relative percentages of quartz, feldspar, and lithic grains and the amount of clay matrix. The composition of a sandstone can provide important information on the genesis of the sediments when used with a triangular Q uartz, F eldspar, L ithic fragment ( QFL diagrams ). However, geologist have not been able to agree on

186-468: A broad range of length and difficulty. The long, easy routes had made the area a common climbing training ground, but the canyon also offers many difficult climbs as well. In recent decades, this broad appeal and the classic nature of many routes have made the area an international destination for rock climbers. Popular sport climbing areas include the Calico Hills and Sandstone Quarry. Red Rock has

248-525: A man's height. The Calico Tanks trail has a plaque about prehistoric agave roasting pits. Ponderosa pines may be found at the top of the valley, where it connects to the Spring Mountains . Wild burros are a familiar sight, as are rabbits and ground squirrels . Desert bighorn sheep are occasionally seen at higher elevations. During rare spring and summer rainstorms, tiny red-spotted toads can emerge from water pools. The Conservation Area

310-614: A mountain-building period called the Laramide orogeny around 66 million years ago, the Keystone Thrust Fault developed. The Keystone is part of a series of thrust faults that ran through much of western North America and the Red Rock Conservation Area. The movement of this fault forced the older gray sedimentary rock over the younger red rocks, forming the varicolored landscape that can be seen in

372-679: A multitude of traditional climbing areas, including single-pitch areas such as Brass Wall and Necromancer Wall, along with multi-pitch areas such as Eagle Wall, Aeolian Wall, Mescalito, and Solar Slab. Long free and big-wall aid routes are found on features such as the Rainbow Wall and Buffalo Wall. Bouldering is popular in Red Rock as well, primarily at the Kraft Boulders and Black Velvet Canyon. Red Rock has hiking trails and picnic areas. Trails are changed and diverted depending on

434-478: A sandstone goes through as the degree of kinetic processing of the sediments increases. Dott's (1964) sandstone classification scheme is one of many such schemes used by geologists for classifying sandstones. Dott's scheme is a modification of Gilbert's classification of silicate sandstones, and it incorporates R.L. Folk's dual textural and compositional maturity concepts into one classification system. The philosophy behind combining Gilbert's and R. L. Folk's schemes

496-462: A set of boundaries separating regions of the QFL triangle. Visual aids are diagrams that allow geologists to interpret different characteristics of a sandstone. For example, a QFL chart can be marked with a provenance model that shows the likely tectonic origin of sandstones with various compositions of framework grains. Likewise, the stage of textural maturity chart illustrates the different stages that

558-627: A side trail of the Old Spanish Trail. The Wilson Cliffs, a massive escarpment, can be seen to the west from SR 159. Toward the southern end of the National Conservation Area are Spring Mountain Ranch State Park ; the town of Blue Diamond ; and Bonnie Springs Ranch , which includes a replica of a western ghost town, but which in 2019 was sold and closed to the public. The first humans were attracted to

620-491: A small sandstone quarry near the northern area of the scenic loop. It proved to be uneconomical and was shut down. Evidence of the quarry's existence includes some of the huge sandstone blocks that have been left behind. The Red Rocks have been a film location for such movies as Roy Rogers and his horse Trigger in Bells of San Angelo (1947) and was a location for The Stalking Moon with Gregory Peck in 1968. In 1967,

682-445: A twofold classification: Cement is what binds the siliciclastic framework grains together. Cement is a secondary mineral that forms after deposition and during burial of the sandstone. These cementing materials may be either silicate minerals or non-silicate minerals, such as calcite. Sandstone that becomes depleted of its cement binder through weathering gradually becomes friable and unstable. This process can be somewhat reversed by

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744-502: Is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains, cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks . Most sandstone is composed of quartz or feldspar , because they are the most resistant minerals to the weathering processes at the Earth's surface. Like uncemented sand , sandstone may be imparted any color by impurities within

806-837: Is a distinction that can be recognized in the field . In turn, the distinction between an orthoquartzite and a metaquartzite is the onset of recrystallization of existing grains. The dividing line may be placed at the point where strained quartz grains begin to be replaced by new, unstrained, small quartz grains, producing a mortar texture that can be identified in thin sections under a polarizing microscope. With increasing grade of metamorphism, further recrystallization produces foam texture , characterized by polygonal grains meeting at triple junctions, and then porphyroblastic texture , characterized by coarse, irregular grains, including some larger grains ( porphyroblasts .) Sandstone has been used since prehistoric times for construction, decorative art works and tools. It has been widely employed around

868-584: Is a protected habitat for the desert tortoise . A habitat at the Visitor Center houses eight females and two males. The Red Rock area has a complex geological history, which over millions of years, helped create the region's dramatic landscape. The Red Rock area was under an ocean basin during the Paleozoic Era 600 million years ago. Up to 9,000 feet (2,700 m) of limey sediments were deposited and eventually lithified to limestone . During

930-748: Is adjacent to the Spring Mountains National Recreation Area on the west side. The conservation area is one of the easternmost parts of the Mojave Desert ; the lowest elevation of the area, from 3,600 to 4,500 feet (1,100 to 1,400 m), is in the Lower Sonoran Zone , while the area from 4,500 feet (1,400 m) up is in the Upper Sonoran Zone . The character of the sandstone layers is such that several year-round springs may be found in

992-847: Is also well known among rockhounds for its hundreds of thousands of iron oxide concretions . Informally, they are called "Moqui marbles" and are believed to represent an extension of Hopi Native American traditions regarding ancestor worship ("moqui" translates to "the dead" in the Hopi language). Thousands of these concretions weather out of outcrops of the Navajo Sandstone within south-central and southeastern Utah within an area extending from Zion National Park eastward to Arches and Canyonland national parks. They are quite abundant within Grand Staircase–Escalante National Monument. The iron oxide concretions found in

1054-493: Is an approximation, from the present to ancient pre-history: Numerous petroglyphs , as well as pottery fragments, remain today throughout the area. In addition, several roasting pits used by the early Native Americans at Red Rock provide further evidence of human activity in the past. In the early 20th century, around the time the first European Americans settled in nearby Las Vegas, the Excelsior Company operated

1116-477: Is an area managed by the Bureau of Land Management as part of its National Landscape Conservation System , and protected as a National Conservation Area . It is about 15 miles (24 km) west of Las Vegas . More than three million people visit the area each year. The conservation area showcases a set of large red rock formations : a set of sandstone peaks and walls that were formed by thrust faults including

1178-548: Is at the start of the loop road. The loop road is also popular for bicycle touring ; it begins with a moderate climb, then is mostly downhill or flat. The Rocky Gap Road in Red Rock Canyon NCA is a side canyon accessible only by an unmaintained primitive road from the scenic loop which mostly only off-road or high-clearance vehicles can access. State Route 159 cuts through the Cottonwood Valley, also

1240-523: Is likely formed during eogenesis. Deeper burial is accompanied by mesogenesis , during which most of the compaction and lithification takes place. Compaction takes place as the sand comes under increasing pressure from overlying sediments. Sediment grains move into more compact arrangements, ductile grains (such as mica grains) are deformed, and pore space is reduced. In addition to this physical compaction, chemical compaction may take place via pressure solution . Points of contact between grains are under

1302-431: Is redeposited in the unstrained pore spaces. Mechanical compaction takes place primarily at depths less than 1,000 meters (3,300 ft). Chemical compaction continues to depths of 2,000 meters (6,600 ft), and most cementation takes place at depths of 2,000–5,000 meters (6,600–16,400 ft). Unroofing of buried sandstone is accompanied by telogenesis , the third and final stage of diagenesis. As erosion reduces

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1364-443: Is that it is better able to "portray the continuous nature of textural variation from mudstone to arenite and from stable to unstable grain composition". Dott's classification scheme is based on the mineralogy of framework grains, and on the type of matrix present in between the framework grains. In this specific classification scheme, Dott has set the boundary between arenite and wackes at 15% matrix. In addition, Dott also breaks up

1426-703: The 'Navajo Country' of the southwestern United States . The two major subunits of the Navajo are the Lamb Point Tongue (Kanab area) and the Shurtz Sandstone Tongue (Cedar City area). The Navajo Sandstone was originally named as the uppermost formation of the La Plata Group by Gregory and Stone in 1917. Baker reassigned it as the upper formation of Glen Canyon Group in 1936. Its age was modified by Lewis and others in 1961. The name

1488-564: The Bureau of Land Management designated 10,000 acres (16 sq mi; 40 km ) as the Red Rock Recreation Lands. In 1973, the U.S. House of Representatives subcommittee on Federal Conservation Areas held a special hearing in the Foley Federal Office Building in downtown Las Vegas to review a legislative resolution sponsored by Nevada's lone Congressman, David Towell (R-NV) to establish

1550-720: The Kayenta Formation of the Glen Canyon Group. Together, these formations can result in immense vertical cliffs of up to 2,200 feet (670 m). Atop the cliffs, Navajo Sandstone often appears as massive rounded domes and bluffs that are generally white in color. Navajo Sandstone frequently occurs as spectacular cliffs, cuestas , domes, and bluffs rising from the desert floor. It can be distinguished from adjacent Jurassic sandstones by its white to light pink color, meter-scale cross-bedding , and distinctive rounded weathering. The wide range of colors exhibited by

1612-513: The Mesozoic Era 250 million years ago, the Earth's crust started to rise due to tectonic shifts, and marine shales and sandstones were deposited. As the basin became isolated evaporite formations of salt and gypsum were deposited. Oxidation of the iron minerals in the sediments resulted in the red colors of some of the rocks. Deposition by streams and in swamp environments resulted in

1674-498: The percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs . Quartz-bearing sandstone can be changed into quartzite through metamorphism , usually related to tectonic compression within orogenic belts . Sandstones are clastic in origin (as opposed to either organic , like chalk and coal , or chemical , like gypsum and jasper ). The silicate sand grains from which they form are

1736-420: The 13-mile scenic drive. ATV use is not permitted in the area. Aside from the dangers of climbing rock faces and cliffs, visitors are informed that temperatures can routinely exceed 105 °F (41 °C) in the summer, so they must bring plenty of water. Visitors hiking into the backcountry off established trails are advised against traveling alone and should inform other people of their plans. Risks include

1798-480: The Keystone Thrust. The walls are up to 3,000 feet (910 m) high, making them a popular hiking and rock climbing destination. The highest point is La Madre Mountain , at 8,154 feet (2,485 m). A one-way, loop road, 13 miles (21 km) long, provides vehicle access to many of the features in the area. Several side roads and parking areas allow access to many of the area trails. A visitor center

1860-480: The Navajo Sandstone a brilliant white. Reducing fluids transported the iron in solution until they mixed with oxidizing groundwater. Where the oxidizing and reducing fluids mixed, the iron precipitated within the Navajo Sandstone. Depending on local variations within the permeability, porosity, fracturing, and other inherent rock properties of the sandstone, varying mixtures of hematite, goethite, and limonite precipitated within spaces between quartz grains. Variations in

1922-466: The Navajo Sandstone exhibit a wide variety of sizes and shapes. Their shape ranges from spheres to discs; buttons; spiked balls; cylindrical hollow pipe-like forms; and other odd shapes. Although many of these concretions are fused together like soap bubbles, many more also occur as isolated concretions, which range in diameter from the size of peas to baseballs. The surface of these spherical concretions can range from being very rough to quite smooth. Some of

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1984-401: The Navajo Sandstone reflect a long history of alteration by groundwater and other subsurface fluids over the last 190 million years. The different colors, except for white, are caused by the presence of varying mixtures and amounts of hematite , goethite , and limonite filling the pore space within the quartz sand comprising the Navajo Sandstone. The iron in these strata originally arrived via

2046-439: The Navajo Sandstone while deeply buried, reducing fluids , likely hydrocarbons , dissolved these coatings. When the reducing fluids containing dissolved iron mixed with oxidizing groundwater , they and the dissolved iron were oxidized. This caused the iron to precipitate out as hematite and goethite to form the innumerable concretions found in the Navajo Sandstone. Evidence suggests that microbial metabolism may have contributed to

2108-651: The Red Rock Conservation Area by transferring Federal land to the State of Nevada. Testimony in favor of the bill was given by the Sierra Club and a high school student and environmental activist, Dennis Causey. The subcommittee unanimously approved the resolution, sending it to the full Committee on the Interior and subsequently to the full House, followed by favorable action by the U S. Senate and approval by President George H. W. Bush . Further legislation in 1990 changed

2170-426: The Red Rock area due to its resources of water, plant, and animal life that could not be easily found in the surrounding desert. Hunters and gatherers such as the historical Southern Paiute and the much older Archaic, or Desert Culture Native Americans, have successively occupied this area. As many as six different Native American cultures may have been present at Red Rock over the millennia. The following chronology

2232-957: The Western portion of the Supercontinent Pangaea . This region was affected by annual monsoons that came about each winter when cooler winds and wind reversal occurred. Navajo Sandstone outcrops are found in these geologic locations: The formation is also found in these parklands (incomplete list): Indeterminate theropod remains geographically located in Arizona, USA. Theropod tracks are geographically located in Arizona, Colorado, and Utah, USA. Ornithischian tracks located in Arizona, USA. Ammosaurus Ammosaurus cf. major Dilophosaurus D. wetherilli Attributed trackways at Red Fleet State Park . Pteraichnus Segisaurus S. halli "Partial postcranial skeleton." Seitaad S. ruessi The Navajo Sandstone

2294-410: The ability of the desert to heal itself over time, is visible from the loop road. Recent fires were in part fueled by the thick growth of invasive species red brome and cheat grasses . The Bureau of Land Management has not developed plans to control these species, because control methods, such as using herbicides , can be costly and damaging to native plants. Sandstone Sandstone

2356-491: The application of tetraethyl orthosilicate (Si(OC 2 H 5 ) 4 ) which will deposit amorphous silicon dioxide between the sand grains. The reaction is as follows. Pore space includes the open spaces within a rock or a soil. The pore space in a rock has a direct relationship to the porosity and permeability of the rock. The porosity and permeability are directly influenced by the way the sand grains are packed together. Sandstones are typically classified by point-counting

2418-473: The common minerals most resistant to weathering processes at the Earth's surface, as seen in the Goldich dissolution series . Framework grains can be classified into several different categories based on their mineral composition: Matrix is very fine material, which is present within interstitial pore space between the framework grains. The nature of the matrix within the interstitial pore space results in

2480-409: The concretions are grooved spheres with ridges around their circumference. The abundant concretions found in the Navajo Sandstone consist of sandstone cemented together by hematite (Fe 2 O 3 ), and goethite (FeOOH). The iron forming these concretions came from the breakdown of iron-bearing silicate minerals by weathering to form iron oxide coatings on other grains. During later diagenesis of

2542-456: The depositional environment, older sand is buried by younger sediments, and it undergoes diagenesis . This mostly consists of compaction and lithification of the sand. Early stages of diagenesis, described as eogenesis , take place at shallow depths (a few tens of meters) and are characterized by bioturbation and mineralogical changes in the sands, with only slight compaction. The red hematite that gives red bed sandstones their color

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2604-407: The depth of burial, renewed exposure to meteoric water produces additional changes to the sandstone, such as dissolution of some of the cement to produce secondary porosity . Framework grains are sand-sized (0.0625-to-2-millimeter (0.00246 to 0.07874 in) diameter) detrital fragments that make up the bulk of a sandstone. Most framework grains are composed of quartz or feldspar , which are

2666-446: The different types of framework grains that can be present in a sandstone into three major categories: quartz, feldspar, and lithic grains. When sandstone is subjected to the great heat and pressure associated with regional metamorphism , the individual quartz grains recrystallize, along with the former cementing material, to form the metamorphic rock called quartzite . Most or all of the original texture and sedimentary structures of

2728-418: The erosion of iron-bearing silicate minerals . Initially, this iron accumulated as iron-oxide coatings, which formed slowly after the sand had been deposited. Later, after having been deeply buried, reducing fluids composed of water and hydrocarbons flowed through the thick red sand which once comprised the Navajo Sandstone. The dissolution of the iron coatings by the reducing fluids bleached large volumes of

2790-400: The formation of petrified wood in the area. By 180 million years ago, the climate continued to change and the area became a desert with vast expanses of huge shifting sand dunes . These dunes accumulated over a broad area, up to 0.5 miles (0.80 km) thick, and were lithified , cemented with calcium carbonate and iron oxides. They developed as the colorful Aztec Sandstone . During

2852-545: The formation of some of these concretions. These concretions are regarded as terrestrial analogues of the hematite spherules, called alternately Martian "blueberries" or more technically Martian spherules , which the Opportunity rover found at Meridiani Planum on Mars . Red Rock Canyon National Conservation Area The Red Rock Canyon National Conservation Area in Clark County, Nevada , United States,

2914-433: The greatest strain, and the strained mineral is more soluble than the rest of the grain. As a result, the contact points are dissolved away, allowing the grains to come into closer contact. Lithification follows closely on compaction, as increased temperatures at depth hasten deposition of cement that binds the grains together. Pressure solution contributes to cementing, as the mineral dissolved from strained contact points

2976-442: The hardness of individual grains, uniformity of grain size and friability of their structure, some types of sandstone are excellent materials from which to make grindstones , for sharpening blades and other implements. Non-friable sandstone can be used to make grindstones for grinding grain, e.g., gritstone . A type of pure quartz sandstone, orthoquartzite, with more of 90–95 percent of quartz, has been proposed for nomination to

3038-540: The ironstone weathered out as ledges, walls, fins, "flags", towers, and other minor features, which stick out and above the local landscape in unusual shapes. The age of the Navajo Sandstone is somewhat controversial. It may originate from the Late Triassic but is at least as young as the Early Jurassic stages Pliensbachian and Toarcian . There is no type locality of the name. It was simply named for

3100-491: The minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Because sandstone beds can form highly visible cliffs and other topographic features, certain colors of sandstone have become strongly identified with certain regions, such as the red rock deserts of Arches National Park and other areas of the American Southwest . Rock formations composed of sandstone usually allow

3162-647: The mountain today. The thrust is exposed over a distance of 13 miles (21 km) along the Red Rock escarpment . The Lee Canyon thrust plate may contain over 4,000 ft (1,200 m) of terrigenous rocks at the base. The Wheeler Pass thrust may contain at least 11,000 ft (3,300 m) of these rocks as well. Red Rock provides a wide variety of recreational activities, the most popular being hiking , biking , rock scrambling , and rock climbing . Horseback riding and camping are also allowed on specific trails and in designated areas. Automobile (Flat4LV) and motorcycle (Roughriders) clubs often conduct group drives through

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3224-493: The much lower temperatures and pressures associated with diagenesis of sedimentary rock, but diagenesis has cemented the rock so thoroughly that microscopic examination is necessary to distinguish it from metamorphic quartzite. The term orthoquartzite is used to distinguish such sedimentary rock from metaquartzite produced by metamorphism. By extension, the term orthoquartzite has occasionally been more generally applied to any quartz-cemented quartz arenite . Orthoquartzite (in

3286-464: The narrow sense) is often 99% SiO 2 with only very minor amounts of iron oxide and trace resistant minerals such as zircon , rutile and magnetite . Although few fossils are normally present, the original texture and sedimentary structures are preserved. The typical distinction between a true orthoquartzite and an ordinary quartz sandstone is that an orthoquartzite is so highly cemented that it will fracture across grains, not around them. This

3348-630: The needs of the ecosystem. In early spring, depending upon the precipitation, waterfalls may be seen on the edge of the canyons. Popular trails within the vicinity of the scenic drive loop include the Moenkopi Loop, Calico Hills, Calico Tanks, Turtlehead Peak, Keystone Thrust, White Rock/La Madre Springs Loop, and the Ice Box Canyon trail. Several significant wildfires have burned within the Red Rock Canyon NCA in recent years, including: Damage caused by wildfires, as well as evidence of

3410-571: The presence of venomous rattlesnakes and flash flooding/lightning from thunderstorms . Although the Yosemite-size walls offer a host of challenging lines, technical climbing activity in Red Rock was not recorded before 1968. The first modern routes, climbed in the early 1970s, are described in several books. The rock is Aztec Sandstone , a relatively solid variety with hard surface varnish. Many climbs involve ascents of single crack systems hundreds of feet long. The climbs of Red Rock cover

3472-638: The product of physical and chemical weathering of bedrock. Weathering and erosion are most rapid in areas of high relief, such as volcanic arcs , areas of continental rifting , and orogenic belts . Eroded sand is transported by rivers or by the wind from its source areas to depositional environments where tectonics has created accommodation space for sediments to accumulate. Forearc basins tend to accumulate sand rich in lithic grains and plagioclase . Intracontinental basins and grabens along continental margins are also common environments for deposition of sand. As sediments continue to accumulate in

3534-514: The recesses of the side canyons. Some 600 species of plants are known in the area. Common types in the valley floor include the Joshua tree , Mojave yucca , banana yucca , creosote , and blackbrush . Higher up the Utah juniper and Sonoran scrub oak (also called scrub live oak) come to dominate. Agave is easy to spot in red rock niches, with its thick, low leaves and flowering stem reaching twice

3596-417: The sandstone are erased by the metamorphism. The grains are so tightly interlocked that when the rock is broken, it fractures through the grains to form an irregular or conchoidal fracture. Geologists had recognized by 1941 that some rocks show the macroscopic characteristics of quartzite, even though they have not undergone metamorphism at high pressure and temperature. These rocks have been subject only to

3658-496: The status of the Red Rock Recreation Lands to a National Conservation Area, a status that also provides funds to maintain and protect it. The Federal area was adjacent to the Red Rock State Park. The Howard Hughes Corporation , developer of Summerlin , has transferred land adjacent to the protected area, to provide a buffer between the development and the conservation area. Red Rock Canyon National Conservation Area

3720-402: The type and proportions of precipitated iron oxides resulted in the different black, brown, crimson, vermillion, orange, salmon, peach, pink, gold, and yellow colors of the Navajo Sandstone. The precipitation of iron oxides also formed laminae, corrugated layers, columns, and pipes of ironstone within the Navajo Sandstone. Being harder and more resistant to erosion than the surrounding sandstone,

3782-626: The world in constructing temples, churches, homes and other buildings, and in civil engineering . Although its resistance to weathering varies, sandstone is easy to work. That makes it a common building and paving material, including in asphalt concrete . However, some types that have been used in the past, such as the Collyhurst sandstone used in North West England , have had poor long-term weather resistance, necessitating repair and replacement in older buildings. Because of

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3844-523: Was originally not used in northwest Colorado and northeast Utah, where the name 'Glen Canyon Sandstone' was preferred. Its age was modified again by Padian in 1989. A 2019 radioisotopic analysis suggests that the Navajo Sandstone formation is entirely Jurassic, extending for about 5.5 million years from the Hettangian age to the Sinemurian age . The sandstone was deposited in an arid erg on

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