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Summerville Formation
The Summerville Formation is a geological formation in New Mexico, Colorado, and Utah of the Southwestern United States. It dates back to the Oxfordian stage of the Late Jurassic.Wilcox 2007 Description The formation consists of up to of red mudstone, with thin interbeds of green and red sandstone. The lower portion of the formation shows polygonal desiccation cracks and localized salt-hopper casts while the upper portion contains considerable gypsum, consistent with deposition in a sabkha on the margin of the Sundance Sea.It is exposed in the San Rafael Reef, the Waterpocket Fold, in the Henry Mountains, with additional exposures scattered across the region from the San Rafael Reef to the Paradox Basin, and in north-central New Mexico. The thin bedding is characteristic throughout the formation, but gypsum is not found in the San Juan Basin and some conglomerate is found on the south and southwestern margins of the formation.Lucas and Anderson 1992, p.81 The correlation of late ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Formation
A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of a geologic formation goes back to the beginnings of modern scientific geology. The term was used by Abraham Gottlob Wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colorado
Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains. Colorado is the eighth most extensive and 21st most populous U.S. state. The 2020 United States census enumerated the population of Colorado at 5,773,714, an increase of 14.80% since the 2010 United States census. The region has been inhabited by Native Americans and their ancestors for at least 13,500 years and possibly much longer. The eastern edge of the Rocky Mountains was a major migration route for early peoples who spread throughout the Americas. "''Colorado''" is the Spanish adjective meaning "ruddy", the color of the Fountain Formation outcroppings found up and down the Front Range of the Rocky Mountains. The Territory of Colorado was organized on February 28, 1861, and on August 1, 1876, U.S. President Ulyss ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moab, Utah
Moab () is the largest city and county seat of Grand County in eastern Utah in the western United States, known for its dramatic scenery. The population was 5,366 at the 2020 census. Moab attracts many tourists annually, mostly visitors to the nearby Arches and Canyonlands National Parks. The town is a popular base for mountain bikers who ride the extensive network of trails including the Slickrock Trail, and for off-roaders who come for the annual Moab Jeep Safari. History Early years The Biblical name Moab refers to an area of land located on the eastern side of the Jordan River. Some historians believe the city in Utah came to use this name because of William Andrew Peirce, the first postmaster, believing that the biblical Moab and this part of Utah were both "the far country". However, others believe the name has Paiute origins, referring to the word ''moapa'', meaning "mosquito". Some of the area's early residents attempted to change the city's name, because in the Chr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unconformity
An unconformity is a buried erosional or non-depositional surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the older layer was exposed to erosion for an interval of time before deposition of the younger layer, but the term is used to describe any break in the sedimentary geologic record. The significance of angular unconformity (see below) was shown by James Hutton, who found examples of Hutton's Unconformity at Jedburgh in 1787 and at Siccar Point in 1788. The rocks above an unconformity are younger than the rocks beneath (unless the sequence has been overturned). An unconformity represents time during which no sediments were preserved in a region or were subsequently eroded before the next deposition. The local record for that time interval is missing and geologists must use other clues to discover that part of the geologic history of that area. The interval of geologic time not represented is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beclabito Formation
The Beclabito Formation is a late Jurassic sedimentary geologic formation, found in northwestern New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe , LargestCity = Albuquerque , LargestMetro = Tiguex , OfficialLang = None , Languages = English, Spanish ( New Mexican), Navajo, Ker ... and northeastern Arizona. Description The formation is composed mostly of thinly bedded sandstone, siltstone, and mudstone which is reddish-orange to reddish-brown in color. The sandstone is very fine to medium grained and displays ripple crossbedding, trough crossbedding, and horizontal Lamination (geology), laminations. The siltstones are reddish-brown and show wavy laminations. The formation is thick. The formation Contact (geology)#Conformable, conformably overlies the Todilto Formation and conformably underlies the Bluff Formation. The formation is interpreted as having been deposited in a marginal marine or coastal s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
San Juan Basin
The San Juan Basin is a geologic structural basin located near the Four Corners region of the Southwestern United States. The basin covers 7,500 square miles and resides in northwestern New Mexico, southwestern Colorado, and parts of Utah and Arizona. Specifically, the basin occupies space in the San Juan, Rio Arriba, Sandoval, and McKinley counties in New Mexico, and La Plata and Archuleta counties in Colorado. The basin extends roughly N-S and E-W. The San Juan Basin is an asymmetric structural depression in the Colorado Plateau province, with varying elevation and nearly in topographic relief. Its most striking features include Chaco Canyon (northwestern New Mexico, between Farmington and Santa Fe) and Chacra Mesa. The basin lies west of the Continental Divide, and its main drainage is the southwest- to west-flowing San Juan River, which eventually joins the Colorado River in Utah. Climate of the basin is arid to semiarid, with an annual precipitation of and an a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waterpocket Fold
The Waterpocket Fold is a geologic landform that extends from southern Wayne through Garfield and ending in northern Kane counties of southern Utah, United States.''Utah Atlas & Gazeteer,'' DeLorme, 9th ed., 2014, pp. 44, 52, 60-1 The geologic structure, formed during the Laramide orogeny, is a south-southeast trending fold in which the east side is dropped relative to the west side. This monoclinal fold extends for nearly in the semi-arid plateau of the central part of the state. The structure defines the Capitol Reef National Park in southern Utah. The feature can be observed in three scenic routes in the park. The park's Scenic Drive leads to a famous landmark known as the Golden Throne. The northern portion of the Waterpocket Fold lies north and east of the town of Fruita, west and just southeast of the Middle Desert. Utah State Route 24 crosses the fold east of Fruita. Notom Road runs south through Notom and runs parallel to the east (downdropped) side of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
San Rafael Reef
The San Rafael Reef is a geologic feature located in Emery County in central Utah, part of the Colorado Plateau. Approximately 75 miles (120 km) long, it is the name given to the distinctive eastern edge of the San Rafael Swell. Composed primarily of steeply tilted layers of Navajo and Wingate Sandstone, it has been eroded into tall fins, domes, cliffs, and deep canyons. The San Rafael River, Interstate 70, and Muddy Creek all cut through the San Rafael Reef. There are also numerous slot canyons that twist their way through the flanks of the San Rafael Reef, among them Crack Canyon, Chute Canyon and Straight Wash. These spectacularly beautiful canyons are often just a few feet wide and can be hundreds of feet deep. Wilderness The eastern edge of the San Rafael Swell Recreation area is protected as the San Rafael Reef Wilderness, designated in 2019 by the U.S. Congress. The 60,442 acre wilderness area is managed by the U.S. Bureau of Land Management The Bureau of Land ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sundance Sea
The Sundance Sea was an epeiric sea that existed in North America during the mid-to-late Jurassic Period of the Mesozoic Era. It was an arm of what is now the Arctic Ocean, and extended through what is now western Canada into the central western United States. The sea receded when highlands to the west began to rise. Stratigraphy The Sundance Sea did not occur at a single time; geological evidence suggests that the Sea was actually a series of five successive marine transgressions—each separated by an erosional hiatus—which advanced and receded from the middle Jurassic onward. The terrestrial sediments of the Morrison Formation—eroded from rising highlands to the west—were deposited on top of the marine Sundance sediments as the sea regressed for the last time late in the Jurassic. Fauna The Sundance Sea was rich in many types of animals. ''Gryphaea'' was extremely common, and shark teeth have been found. In addition to fish, belemnites and to an extent ammonites ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sabkha
A sabkha ( ar, سبخة) is a coastal, supratidal mudflat or sandflat in which evaporite-saline minerals accumulate as the result of semiarid to arid climate. Sabkhas are gradational between land and intertidal zone within restricted coastal plains just above normal high-tide level. Within a sabkha, evaporite-saline minerals sediments typically accumulate below the surface of mudflats or sandflats. Evaporite-saline minerals, tidal-flood, and aeolian deposits characterize many sabkhas found along modern coastlines. The accepted type locality for a sabkha is at the southern coast of the Persian Gulf, in the United Arab Emirates.Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, eds. (2005) ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. Tucker, M.E. and Wright, V.P., 2009. ''Carbonate sedimentology.'' John Wiley & Sons. and Warren, J.K., 2006. Evaporites: sediments, resources and hydrocarbons. Springer Science & Business Media.Wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gypsum
Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard or sidewalk chalk, and drywall. Alabaster, a fine-grained white or lightly tinted variety of gypsum, has been used for sculpture by many cultures including Ancient Egypt, Mesopotamia, Ancient Rome, the Byzantine Empire, and the Nottingham alabasters of Medieval England. Gypsum also crystallizes as translucent crystals of selenite. It forms as an evaporite mineral and as a hydration product of anhydrite. The Mohs scale of mineral hardness defines gypsum as hardness value 2 based on scratch hardness comparison. Etymology and history The word ''gypsum'' is derived from the Greek word (), "plaster". Because the quarries of the Montmartre district of Paris have long furnished burnt gypsum (calcined gypsum) used for various purposes, this dehydrated gypsum became known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mudstone
Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Mudstone is distinguished from '' shale'' by its lack of fissility (parallel layering).Blatt, H., and R.J. Tracy, 1996, ''Petrology.'' New York, New York, W. H. Freeman, 2nd ed, 529 pp. The term ''mudstone'' is also used to describe carbonate rocks (limestone or dolomite) that are composed predominantly of carbonate mud. However, in most contexts, the term refers to siliciclastic mudstone, composed mostly of silicate minerals. The NASA Curiosity rover has found deposits of mudstone on Mars that contain organic substances such as propane, benzene and toluene. Definition There is not a single definition of mudstone that has gained general acceptance,Boggs 2006, p.143 though there is wide agreement that mudstones are fine-grained sedimentary rocks, composed mostly of silicate grains with a grain size less than . Individual grains this size are too small to be disting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
