New Mexico is a state in the Southwestern region of the United States of America. It is one of the Mountain States and shares the Four Corners region with Utah and Arizona. With a population around two million, New Mexico is the 36th state by population. With a total area of 121,592 sq mi, it is the fifth-largest and sixth-least densely populated of the 50 states. Due to their geographic locations and eastern New Mexico exhibit a colder, alpine climate, while western and southern New Mexico exhibit a warmer, arid climate; the economy of New Mexico is dependent on oil drilling, mineral extraction, dryland farming, cattle ranching, lumber milling, retail trade. As of 2016–2017, its total gross domestic product was $95 billion with a GDP per capita of $45,465. New Mexico's status as a tax haven yields low to moderate personal income taxes on residents and military personnel, gives tax credits and exemptions to favorable industries; because of this, its film industry contributed $1.23 billion to its overall economy.
Due to its large area and economic climate, New Mexico has a large U. S. military presence marked notably with the White Sands Missile Range. Various U. S. national security agencies base their research and testing arms in New Mexico such as the Sandia and Los Alamos National Laboratories. During the 1940s, Project Y of the Manhattan Project developed and built the country's first atomic bomb and nuclear test, Trinity. Inhabited by Native Americans for many thousands of years before European exploration, it was colonized by the Spanish in 1598 as part of the Imperial Spanish viceroyalty of New Spain. In 1563, it was named Nuevo México after the Aztec Valley of Mexico by Spanish settlers, more than 250 years before the establishment and naming of the present-day country of Mexico. After Mexican independence in 1824, New Mexico became a Mexican territory with considerable autonomy; this autonomy was threatened, however, by the centralizing tendencies of the Mexican government from the 1830s onward, with rising tensions leading to the Revolt of 1837.
At the same time, the region became more economically dependent on the United States. At the conclusion of the Mexican–American War in 1848, the United States annexed New Mexico as the U. S. New Mexico Territory, it was admitted to the Union as the 47th state on January 6, 1912. Its history has given New Mexico the highest percentage of Hispanic and Latino Americans, the second-highest percentage of Native Americans as a population proportion. New Mexico is home to part of the Navajo Nation, 19 federally recognized Pueblo communities of Puebloan peoples, three different federally recognized Apache tribes. In prehistoric times, the area was home to Ancestral Puebloans and the modern extant Comanche and Utes inhabited the state; the largest Hispanic and Latino groups represented include the Hispanos of New Mexico and Mexican Americans. The flag of New Mexico features the state's Spanish origins with the same scarlet and gold coloration as Spain's Cross of Burgundy, along with the ancient sun symbol of the Zia, a Puebloan tribe.
These indigenous, Mexican and American frontier roots are reflected in the eponymous New Mexican cuisine and the New Mexico music genre. New Mexico received its name long before the present-day nation of Mexico won independence from Spain and adopted that name in 1821. Though the name “Mexico” itself derives from Nahuatl, in that language it referred to the heartland of the Empire of the Mexicas in the Valley of Mexico far from the area of New Mexico, Spanish explorers used the term “Mexico” to name the region of New Mexico in 1563. In 1581, the Chamuscado and Rodríguez Expedition named the region north of the Rio Grande "San Felipe del Nuevo México"; the Spaniards had hoped to find wealthy indigenous Mexica cultures there similar to those of the Aztec Empire of the Valley of Mexico. The indigenous cultures of New Mexico, proved to be unrelated to the Mexicas, they were not wealthy, but the name persisted. Before statehood, the name "New Mexico" was applied to various configurations of the U.
S. territory, to a Mexican state, to a province of New Spain, all in the same general area, but of varying extensions. With a total area of 121,699 square miles, the state is the fifth-largest state of the US, larger than British Isles. New Mexico's eastern border lies along 103°W longitude with the state of Oklahoma, 2.2 miles west of 103°W longitude with Texas. On the southern border, Texas makes up the eastern two-thirds, while the Mexican states of Chihuahua and Sonora make up the western third, with Chihuahua making up about 90% of that; the western border with Arizona runs along the 109° 03'W longitude. The southwestern corner of the state is known as the Bootheel; the 37°N parallel forms the northern boundary with Colorado. The states of New Mexico, Colorado and Utah come together at the Four Corners in New Mexico's northwestern corner. New Mexico has no natural water sources
Central Corridor (Union Pacific Railroad)
The Central Corridor is a rail line operated by the Union Pacific Railroad from near Winnemucca, Nevada to Denver, Colorado in the western United States. The line was created after the merger with the Southern Pacific Transportation Company by combining portions of lines built by former competitors. No portion of the line was built by the Union Pacific; the line is known for significant feats of engineering while crossing the Wasatch Mountains of Utah and the Rocky Mountains of Colorado. The line features numerous tunnels, the longest and highest of these is the Moffat Tunnel; the line is used for freight by the Union Pacific. The BNSF Railway has trackage rights on the entire line. However, parts of the line host significant passenger rail traffic. Amtrak's California Zephyr uses the entire length of the Central Corridor, as part of its San Francisco – Chicago route. In addition, the portion from Salt Lake City to Provo, Utah hosts a separate, dedicated track built by the Utah Transit Authority for the southern half of the FrontRunner commuter rail service.
Proceeding east out of Winnemucca, the route follows the Humboldt River, in a directional running setup with the Overland Route until Wells, Nevada. From Wells to Salt Lake, the route, known as the Shafter Subdivision, loosely follows the historical route of the Hastings Cutoff, tunneling underneath the Pequop Mountains and crossing the Toano Range via Silver Zone Pass; the eastern approach to Silver Zone Pass features a near 360 degree horseshoe curve known as the Arnold loop. After crossing these mountain ranges the route proceeds southwest towards the Great Salt Lake Desert. In Nevada, Interstate 80 follows the Central Corridor, though the two routes are several miles apart in places; the route enters Utah at Wendover and crosses the Great Salt Lake Desert and the Bonneville Salt Flats, parallel to Interstate 80 and the Wendover Cut-off, en route to the southern shore of the Great Salt Lake and Salt Lake City. Upon reaching Salt Lake City, the line turns south and follows the Jordan River through Point of the Mountain towards Spanish Fork.
After Spanish Fork, the rail line joins the U. S. Route 6 corridor, the two follow each other towards Denver. Both routes follow the Spanish Fork River up a grade in the Wasatch Plateau, cresting at Soldier Summit; the western approach to Soldier Summit is known for the Gilluly loops, a series of horseshoe curves that allow the railroad to crest the mountains while maintaining grade that never exceeds 2.4%, unlike the highway, built using an older railroad grade, that features grades in excess of 5%. The railroad descends from Soldier Summit following the Price River until reaching the town of Helper, so named because in the era of steam locomotives, the railroad added or removed helper engines here for trains crossing Soldier Summit. Upon exiting the Wasatch Mountains, the train follows the southern rim of the Book Cliffs, in route serving the towns of Woodside, Green River, Thompson Springs and Cisco. Near Cisco is where the rail line for the first time meets the Colorado River, which provides the path up the Rocky Mountains in Colorado.
The rail line crosses the river numerous times in Colorado while ascending the Rockies. Ruby Canyon is. Grand Valley Debeque Canyon Glenwood Canyon Gore Canyon Fraser River Moffat Tunnel Tunnel District Front RangeThe highest point on the line is the Moffat Tunnel. Aside from the now dormant line over Tennessee Pass, this is the highest point on the Union Pacific System. All of the Central Corridor was built by former competitors to the Union Pacific; the portion from Winnemucca to Salt Lake City, Utah was part of the Feather River Route, built by the Western Pacific Railroad, acquired by the Union Pacific in 1983. The portion from Salt Lake City to Grand Junction, Colorado is the former Utah Division of the Denver and Rio Grande Western. From Grand Junction to Dotsero, Colorado was part of the Tennessee Pass Line built by the D&RGW. From Dotsero to Bond, Colorado is the former Dotsero Cutoff, built by the D&RGW as a connection between their main line with the main of the unfinished Denver and Salt Lake Railroad, which provided the connection from Bond to Denver, Colorado.
The portion east of Salt Lake City came under the Union Pacific's control from the 1996 acquisition of the Southern Pacific Transportation Company. The Western Pacific and D&RGW portions of the line were part of the Gould transcontinental system
Denver and Rio Grande Western Railroad
The Denver & Rio Grande Western Railroad shortened to Rio Grande, D&RG or D&RGW the Denver & Rio Grande Railroad, was an American Class I railroad company. The railroad started as a 3 ft narrow-gauge line running south from Denver, Colorado in 1870, it served as a transcontinental bridge line between Denver, Salt Lake City, Utah. The Rio Grande was a major origin of coal and mineral traffic; the Rio Grande was the epitome of mountain railroading, with a motto of Through the Rockies, not around them and Main line through the Rockies, both referring to the Rocky Mountains. The D&RGW operated the highest mainline rail line in the United States, over the 10,240 feet Tennessee Pass in Colorado, the famed routes through the Moffat Tunnel and the Royal Gorge. At its height in the mid-1880s, the D&RG had the largest narrow-gauge railroad network in North America with 2,783 miles of track interconnecting the states of Colorado, New Mexico, Utah. Known for its independence, the D&RGW operated the Rio Grande Zephyr until its discontinuation in 1983.
This was the last private intercity passenger train in the United States until Brightline began service in Florida in 2018. In 1988, the Rio Grande's parent corporation, Rio Grande Industries, purchased Southern Pacific Transportation Company, as the result of a merger, the larger Southern Pacific Railroad name was chosen for identity; the Rio Grande operated as a separate division of the Southern Pacific, until that company was acquired by the Union Pacific Railroad. Today, most former D&RGW main lines are owned and operated by the Union Pacific while several branch lines are now operated as heritage railways by various companies; the Denver & Rio Grande Railway was incorporated on October 27, 1870 by General William Jackson Palmer, a board of four directors. It was announced that the new 3 ft railroad would proceed south from Denver and travel an estimated 875 miles south to El Paso via Pueblo, westward along the Arkansas River, continue southward through the San Luis Valley of Colorado toward the Rio Grande.
Assisted by his friend and new business partner Dr. William Bell, Palmer's new "Baby Road" laid the first rails out of Denver on July 28, 1871 and reached the location of the new town of Colorado Springs by October 21. Narrow gauge was chosen in part because construction and equipment costs would be more affordable when weighed against that of the prevailing standard gauge. Palmer's first hand impressions of the Ffestiniog Railway in Wales buoyed his interest in the narrow-gauge concept which would prove to be advantageous while conquering the mountainous regions of the Southwest; the route of the D&RG would be amended and added to as new opportunities and competition challenged the railroad's expanding goals. Feverish, competitive construction plans provoked the 1877–1880 war over right of way with the Atchison and Santa Fe Railway. Both rivals hired gunslingers and bought politicians while courts intervened to bring settlement to the disagreements. One anecdote of the conflict recounts June 1879 when the Santa Fe defended its roundhouse in Pueblo with Dodge City toughs led by Bat Masterson.
In March 1880, a Boston Court granted the AT&SF the rights to Raton Pass, while the D&RG paid an exorbitant $1.4 million for the trackage extending through the Arkansas River's Royal Gorge. The D&RG's possession of this route allowed quick access to the booming mining district of Leadville, Colorado. While this "Treaty of Boston" did not favor the purist of original D&RG intentions, the conquering of new mining settlements to the west and the future opportunity to expand into Utah was realized from this settlement. By late 1880 William Bell had begun to organize railway construction in Utah that would become the Palmer controlled Denver & Rio Grande Western Railway in mid-1881; the intention of the D&RGW was to work eastward from Provo to an eventual link with westward bound D&RG in Colorado. This physical connection was realized near Green River, Utah on March 30, 1883, by May of that year the D&RG formally leased its Utah subsidiary as planned. By mid-1883, financial difficulties due to aggressive growth and expenditures led to a shake up among the D&RG board of directors, General Palmer resigned as president of the D&RG in August 1883, while retaining that position with the Western.
Frederick Lovejoy would soon fill Palmer's vacated seat on the D&RG, the first in a succession of post Palmer presidents that would attempt to direct the railroad through future struggles and successes. Following bitter conflict with the Rio Grande Western during lease disagreements and continued financial struggles, the D&RG went into receivership in July 1884 with court appointed receiver William S. Jackson in control. Eventual foreclosure and sale of the original Denver & Rio Grande Railway resulted within two years and the new Denver & Rio Grande Railroad took formal control of the property and holdings on July 14, 1886 with Jackson appointed as president. General Palmer would continue as president of the Utah line until retirement in 1901; the D&RG built west from Pueblo reaching Cañon City in 1874. The line through the Royal Gorge reached Salida on May 20, 1880 and was pushed to Leadville that same year. From Salida, the D&RG pushed west over the Continental Divide at the 10,845 feet Marshall Pass and reached Gunnison on August 6, 1881.
From Gunnison the line entered the Black Canyon of the
Utah is a state in the western United States. It became the 45th state admitted to the U. S. on January 4, 1896. Utah is the 13th-largest by area, 31st-most-populous, 10th-least-densely populated of the 50 United States. Utah has a population of more than 3 million according to the Census estimate for July 1, 2016. Urban development is concentrated in two areas: the Wasatch Front in the north-central part of the state, which contains 2.5 million people. Utah is bordered by Colorado to the east, Wyoming to the northeast, Idaho to the north, Arizona to the south, Nevada to the west, it touches a corner of New Mexico in the southeast. 62% of Utahns are reported to be members of The Church of Jesus Christ of Latter-day Saints, making Utah the only state with a majority population belonging to a single church. This influences Utahn culture and daily life; the LDS Church's world headquarters is located in Salt Lake City. The state is a center of transportation, information technology and research, government services, a major tourist destination for outdoor recreation.
In 2013, the U. S. Census Bureau estimated. St. George was the fastest-growing metropolitan area in the United States from 2000 to 2005. Utah has the 14th highest median average income and the least income inequality of any U. S. state. A 2012 Gallup national survey found Utah overall to be the "best state to live in" based on 13 forward-looking measurements including various economic and health-related outlook metrics. A common folk etymology is that the name "Utah" is derived from the name of the Ute tribe, purported to mean "people of the mountains" in the Ute language. However, the word for people in Ute is'núuchiu' while the word for mountain is'káav', offering no linguistic connection to the words'Ute' or'Utah'. According to other sources "Utah" is derived from the Apache name "yuttahih" which means "One, Higher up" or "Those that are higher up". In the Spanish language it was said as "Yuta", subsequently the English-speaking people adapted the word "Utah". Thousands of years before the arrival of European explorers, the Ancestral Puebloans and the Fremont people lived in what is now known as Utah, some of which spoke languages of the Uto-Aztecan group.
Ancestral Pueblo peoples built their homes through excavations in mountains, the Fremont people built houses of straw before disappearing from the region around the 15th century. Another group of Native Americans, the Navajo, settled in the region around the 18th century. In the mid-18th century, other Uto-Aztecan tribes, including the Goshute, the Paiute, the Shoshone, the Ute people settled in the region; these five groups were present. The southern Utah region was explored by the Spanish in 1540, led by Francisco Vásquez de Coronado, while looking for the legendary Cíbola. A group led by two Catholic priests—sometimes called the Dominguez-Escalante Expedition—left Santa Fe in 1776, hoping to find a route to the coast of California; the expedition encountered the native residents. The Spanish made further explorations in the region, but were not interested in colonizing the area because of its desert nature. In 1821, the year Mexico achieved its independence from Spain, the region became known as part of its territory of Alta California.
European trappers and fur traders explored some areas of Utah in the early 19th century from Canada and the United States. The city of Provo, Utah was named for one, Étienne Provost, who visited the area in 1825; the city of Ogden, Utah was named after Peter Skene Ogden, a Canadian explorer who traded furs in the Weber Valley. In late 1824, Jim Bridger became the first known English-speaking person to sight the Great Salt Lake. Due to the high salinity of its waters, He thought. After the discovery of the lake, hundreds of American and Canadian traders and trappers established trading posts in the region. In the 1830s, thousands of migrants traveling from the Eastern United States to the American West began to make stops in the region of the Great Salt Lake known as Lake Youta. Following the death of Joseph Smith in 1844, Brigham Young, as president of the Quorum of the Twelve, became the effective leader of the LDS Church in Nauvoo, Illinois. To address the growing conflicts between his people and their neighbors, Young agreed with Illinois Governor Thomas Ford in October 1845 that the Mormons would leave by the following year.
Young and the first band of Mormon pioneers reached the Salt Lake Valley on July 24, 1847. Over the next 22 years, more than 70,000 pioneers settled in Utah. For the first few years, Brigham Young and the thousands of early settlers of Salt Lake City struggled to survive; the arid desert land was deemed by the Mormons as desirable as a place where they could practice their religion without harassment. The Mormon settlements provided pioneers for other settlements in the West. Salt Lake City became the hub of a "far-flung commonwealth" of Mormon settlements. With new church converts coming from the East and around the world, Church leaders assigned groups of church members as missionaries to establish other settlements throughout the West, they developed irrigation to support large pioneer populations along Utah's Wasatch front. Throughout the remainder of the 19th century, Mormon pioneers established hundreds of other settlements in Utah, Id
Denver the City and County of Denver, is the capital and most populous municipality of the U. S. state of Colorado. Denver is located in the South Platte River Valley on the western edge of the High Plains just east of the Front Range of the Rocky Mountains; the Denver downtown district is east of the confluence of Cherry Creek with the South Platte River 12 mi east of the foothills of the Rocky Mountains. Denver is named after James W. Denver, a governor of the Kansas Territory, it is nicknamed the Mile High City because its official elevation is one mile above sea level; the 105th meridian west of Greenwich, the longitudinal reference for the Mountain Time Zone, passes directly through Denver Union Station. Denver is ranked as a Beta world city by World Cities Research Network. With an estimated population of 704,621 in 2017, Denver is the 19th-most populous U. S. city, with a 17.41% increase since the 2010 United States Census, it has been one of the fastest-growing major cities in the United States.
The 10-county Denver-Aurora-Lakewood, CO Metropolitan Statistical Area had an estimated 2017 population of 2,888,227 and is the 19th most populous U. S. metropolitan statistical area. The 12-city Denver-Aurora, CO Combined Statistical Area had an estimated 2017 population of 3,515,374 and is the 15th most populous U. S. metropolitan area. Denver is the most populous city of the 18-county Front Range Urban Corridor, an oblong urban region stretching across two states with an estimated 2017 population of 4,895,589. Denver is the most populous city within a 500-mile radius and the second-most populous city in the Mountain West after Phoenix, Arizona. In 2016, Denver was named the best place to live in the United States by U. S. News & World Report. In the summer of 1858, during the Pike's Peak Gold Rush, a group of gold prospectors from Lawrence, Kansas established Montana City as a mining town on the banks of the South Platte River in what was western Kansas Territory; this was the first historical settlement in what was to become the city of Denver.
The site faded however, by the summer of 1859 it was abandoned in favor of Auraria and St. Charles City. On November 22, 1858, General William Larimer and Captain Jonathan Cox, both land speculators from eastern Kansas Territory, placed cottonwood logs to stake a claim on the bluff overlooking the confluence of the South Platte River and Cherry Creek, across the creek from the existing mining settlement of Auraria, on the site of the existing townsite of St. Charles. Larimer named the townsite Denver City to curry favor with Kansas Territorial Governor James W. Denver. Larimer hoped the town's name would help make it the county seat of Arapaho County but, unbeknownst to him, Governor Denver had resigned from office; the location was accessible to existing trails and was across the South Platte River from the site of seasonal encampments of the Cheyenne and Arapaho. The site of these first towns is now the site of Confluence Park near downtown Denver. Larimer, along with associates in the St. Charles City Land Company, sold parcels in the town to merchants and miners, with the intention of creating a major city that would cater to new immigrants.
Denver City was a frontier town, with an economy based on servicing local miners with gambling, saloons and goods trading. In the early years, land parcels were traded for grubstakes or gambled away by miners in Auraria. In May 1859, Denver City residents donated 53 lots to the Leavenworth & Pike's Peak Express in order to secure the region's first overland wagon route. Offering daily service for "passengers, mail and gold", the Express reached Denver on a trail that trimmed westward travel time from twelve days to six. In 1863, Western Union furthered Denver's dominance of the region by choosing the city for its regional terminus; the Colorado Territory was created on February 28, 1861, Arapahoe County was formed on November 1, 1861, Denver City was incorporated on November 7, 1861. Denver City served as the Arapahoe County Seat from 1861 until consolidation in 1902. In 1867, Denver City became the acting territorial capital, in 1881 was chosen as the permanent state capital in a statewide ballot.
With its newfound importance, Denver City shortened its name to Denver. On August 1, 1876, Colorado was admitted to the Union. Although by the close of the 1860s, Denver residents could look with pride at their success establishing a vibrant supply and service center, the decision to route the nation's first transcontinental railroad through Cheyenne, rather than Denver, threatened the prosperity of the young town. A daunting 100 miles away, citizens mobilized to build a railroad to connect Denver to the transcontinental railroad. Spearheaded by visionary leaders including Territorial Governor John Evans, David Moffat, Walter Cheesman, fundraising began. Within three days, $300,000 had been raised, citizens were optimistic. Fundraising stalled before enough was raised, forcing these visionary leaders to take control of the debt-ridden railroad. Despite challenges, on June 24, 1870, citizens cheered as the Denver Pacific completed the link to the transcontinental railroad, ushering in a new age of prosperity for Denver.
Linked to the rest of the nation by rail, Denver prospered as a service and supply center. The young city grew during these years, attracting millionaires with their mansions, as well as the poverty and crime of a growing city. Denver citizens were proud when the rich chose Denver and were thrilled when Horace Tabor, the Leadville mining millionaire, built an impressive business block at 16th and Larimer as well as the el
Sedimentary rocks are types of rock that are formed by the accumulation or deposition of small particules and subsequent cementation of mineral or organic particles on the floor of oceans or other bodies of water at the Earth's surface. Sedimentation is the collective name for processes; the particles that form a sedimentary rock are called sediment, may be composed of geological detritus or biological detritus. Before being deposited, the geological detritus was formed by weathering and erosion from the source area, transported to the place of deposition by water, ice, mass movement or glaciers, which are called agents of denudation. Biological detritus was formed by bodies and parts of dead aquatic organisms, as well as their fecal mass, suspended in water and piling up on the floor of water bodies. Sedimentation may occur as dissolved minerals precipitate from water solution; the sedimentary rock cover of the continents of the Earth's crust is extensive, but the total contribution of sedimentary rocks is estimated to be only 8% of the total volume of the crust.
Sedimentary rocks are only a thin veneer over a crust consisting of igneous and metamorphic rocks. Sedimentary rocks are deposited in layers as strata; the study of sedimentary rocks and rock strata provides information about the subsurface, useful for civil engineering, for example in the construction of roads, tunnels, canals or other structures. Sedimentary rocks are important sources of natural resources like coal, fossil fuels, drinking water or ores; the study of the sequence of sedimentary rock strata is the main source for an understanding of the Earth's history, including palaeogeography and the history of life. The scientific discipline that studies the properties and origin of sedimentary rocks is called sedimentology. Sedimentology is part of both geology and physical geography and overlaps with other disciplines in the Earth sciences, such as pedology, geomorphology and structural geology. Sedimentary rocks have been found on Mars. Sedimentary rocks can be subdivided into four groups based on the processes responsible for their formation: clastic sedimentary rocks, biochemical sedimentary rocks, chemical sedimentary rocks, a fourth category for "other" sedimentary rocks formed by impacts and other minor processes.
Clastic sedimentary rocks are composed of other rock fragments that were cemented by silicate minerals. Clastic rocks are composed of quartz, rock fragments, clay minerals, mica. Clastic sedimentary rocks, are subdivided according to the dominant particle size. Most geologists use the Udden-Wentworth grain size scale and divide unconsolidated sediment into three fractions: gravel and mud; the classification of clastic sedimentary rocks parallels this scheme. This tripartite subdivision is mirrored by the broad categories of rudites and lutites in older literature; the subdivision of these three broad categories is based on differences in clast shape, grain size or texture. Conglomerates are dominantly composed of rounded gravel, while breccias are composed of dominantly angular gravel. Sandstone classification schemes vary but most geologists have adopted the Dott scheme, which uses the relative abundance of quartz and lithic framework grains and the abundance of a muddy matrix between the larger grains.
Composition of framework grains The relative abundance of sand-sized framework grains determines the first word in a sandstone name. Naming depends on the dominance of the three most abundant components quartz, feldspar, or the lithic fragments that originated from other rocks. All other minerals are considered accessories and not used in the naming of the rock, regardless of abundance. Quartz sandstones have >90% quartz grains Feldspathic sandstones have <90% quartz grains and more feldspar grains than lithic grains Lithic sandstones have <90% quartz grains and more lithic grains than feldspar grainsAbundance of muddy matrix material between sand grains When sand-sized particles are deposited, the space between the grains either remains open or is filled with mud. "Clean" sandstones with open pore space are called arenites. Muddy sandstones with abundant muddy matrix are called wackes. Six sandstone names are possible using the descriptors for grain composition and the amount of matrix. For example, a quartz arenite would be composed of quartz grains and have little or no clayey matrix between the grains, a lithic wacke would have abundant lithic grains and abundant muddy matrix, etc.
Although the Dott classification scheme is used by sedimentologists, common names like greywacke and quartz sandstone are still used by non-specialists and in popular literature. Mudrocks are sedimentary rocks composed of at least 50% silt- and clay-sized particles; these fine-grained particles are transported by turbulent flow in water or air, deposited as the flow calms and the particles settle out of suspension. Most authors presently
OCLC Online Computer Library Center, Incorporated d/b/a OCLC is an American nonprofit cooperative organization "dedicated to the public purposes of furthering access to the world's information and reducing information costs". It was founded in 1967 as the Ohio College Library Center. OCLC and its member libraries cooperatively produce and maintain WorldCat, the largest online public access catalog in the world. OCLC is funded by the fees that libraries have to pay for its services. OCLC maintains the Dewey Decimal Classification system. OCLC began in 1967, as the Ohio College Library Center, through a collaboration of university presidents, vice presidents, library directors who wanted to create a cooperative computerized network for libraries in the state of Ohio; the group first met on July 5, 1967 on the campus of the Ohio State University to sign the articles of incorporation for the nonprofit organization, hired Frederick G. Kilgour, a former Yale University medical school librarian, to design the shared cataloging system.
Kilgour wished to merge the latest information storage and retrieval system of the time, the computer, with the oldest, the library. The plan was to merge the catalogs of Ohio libraries electronically through a computer network and database to streamline operations, control costs, increase efficiency in library management, bringing libraries together to cooperatively keep track of the world's information in order to best serve researchers and scholars; the first library to do online cataloging through OCLC was the Alden Library at Ohio University on August 26, 1971. This was the first online cataloging by any library worldwide. Membership in OCLC is based on use of services and contribution of data. Between 1967 and 1977, OCLC membership was limited to institutions in Ohio, but in 1978, a new governance structure was established that allowed institutions from other states to join. In 2002, the governance structure was again modified to accommodate participation from outside the United States.
As OCLC expanded services in the United States outside Ohio, it relied on establishing strategic partnerships with "networks", organizations that provided training and marketing services. By 2008, there were 15 independent United States regional service providers. OCLC networks played a key role in OCLC governance, with networks electing delegates to serve on the OCLC Members Council. During 2008, OCLC commissioned two studies to look at distribution channels. In early 2009, OCLC negotiated new contracts with the former networks and opened a centralized support center. OCLC provides bibliographic and full-text information to anyone. OCLC and its member libraries cooperatively produce and maintain WorldCat—the OCLC Online Union Catalog, the largest online public access catalog in the world. WorldCat has holding records from private libraries worldwide; the Open WorldCat program, launched in late 2003, exposed a subset of WorldCat records to Web users via popular Internet search and bookselling sites.
In October 2005, the OCLC technical staff began a wiki project, WikiD, allowing readers to add commentary and structured-field information associated with any WorldCat record. WikiD was phased out; the Online Computer Library Center acquired the trademark and copyrights associated with the Dewey Decimal Classification System when it bought Forest Press in 1988. A browser for books with their Dewey Decimal Classifications was available until July 2013; until August 2009, when it was sold to Backstage Library Works, OCLC owned a preservation microfilm and digitization operation called the OCLC Preservation Service Center, with its principal office in Bethlehem, Pennsylvania. The reference management service QuestionPoint provides libraries with tools to communicate with users; this around-the-clock reference service is provided by a cooperative of participating global libraries. Starting in 1971, OCLC produced catalog cards for members alongside its shared online catalog. OCLC commercially sells software, such as CONTENTdm for managing digital collections.
It offers the bibliographic discovery system WorldCat Discovery, which allows for library patrons to use a single search interface to access an institution's catalog, database subscriptions and more. OCLC has been conducting research for the library community for more than 30 years. In accordance with its mission, OCLC makes its research outcomes known through various publications; these publications, including journal articles, reports and presentations, are available through the organization's website. OCLC Publications – Research articles from various journals including Code4Lib Journal, OCLC Research, Reference & User Services Quarterly, College & Research Libraries News, Art Libraries Journal, National Education Association Newsletter; the most recent publications are displayed first, all archived resources, starting in 1970, are available. Membership Reports – A number of significant reports on topics ranging from virtual reference in libraries to perceptions about library funding. Newsletters – Current and archived newsletters for the library and archive community.
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