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Leyden, Colorado
Leyden, Colorado, elevation is a small unincorporated community in Jefferson County, Colorado west of Arvada at the junction of West 82nd Avenue and Quaker Street. It is a historic company town established by the Leyden Coal Company in 1902 to house the miners of the Leyden Coal Mine nearby to the west. History The town of Leyden consists of a collection of square frame homes with pyramidal roofs that were originally red trimmed in white. It was named for pioneer miner brothers Michael, Martin and John Leyden, who discovered the original Leyden mine in the hogback ridge to the west, where Michael and Martin died in 1866 and 1870, respectively. At its height, the town of Leyden included these homes as well as the company store, school, boarding house, saloon, and Presbyterian chapel. The store still stands at the southeast corner of 82nd and Quaker, while the school is the easternmost house on the hillside to the north, and the foreman's house stands next door to its west. The to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jefferson County, Colorado
Jefferson County is a county located in the U.S. state of Colorado. As of the 2020 census, the population was 582,910, making it the fourth-most populous county in Colorado. The county seat is Golden, and the most populous city is Lakewood. Jefferson County is included in the Denver-Aurora-Lakewood, CO Metropolitan Statistical Area. Located along the Front Range of the Rocky Mountains, Jefferson County is adjacent to the state capital of Denver. In 2010, the center of population of Colorado was located in Jefferson County. The county's slogan is the "Gateway to the Rocky Mountains", and it is commonly nicknamed Jeffco. The name Jeffco is incorporated in the name of the Jeffco School District, the Jeffco Business Center Metropolitan District No. 1, and several businesses located in Jefferson County. Jeffco is also incorporated in the unofficial monikers of many Jefferson County agencies. The Rocky Mountain Metropolitan Airport operated by Jefferson County was previously know ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arvada, Colorado
Arvada () is a home rule municipality located in Jefferson and Adams counties, Colorado, United States. The city population was 124,402 at the 2020 United States Census, with 121,510 residing in Jefferson County and 2,892 residing in Adams County. Arvada is the seventh most populous city in Colorado. The city is a part of the Denver–Aurora–Lakewood, CO Metropolitan Statistical Area and the Front Range Urban Corridor. The Olde Town Arvada historic district is 7 miles (11 km) northwest of the Colorado State Capitol in Denver. History The first documented discovery of gold in the Rocky Mountain region occurred on June 22, 1850, when Lewis Ralston, a Georgia prospector headed for the California gold fields, dipped his sluice pan into a small stream near its mouth at Clear Creek. Ralston found about 1/4 ounce (6 g) of gold, then worth about five dollars. Ralston's companions named the stream Ralston's Creek in his honor, but they all left the next morning, drawn by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sub-bituminous Coal
Sub-bituminous coal is a lower grade of coal that contains 35–45% carbon. The properties of this type are between those of lignite, the lowest grade of coal, and those of bituminous coal, the second-highest grade of coal. Sub-bituminous coal is primarily used as a fuel for steam-electric power generation. Properties Sub-bituminous coals may be dull, dark brown to black, soft and crumbly at the lower end of the range, to bright jet-black, hard, and relatively strong at the upper end. They contain 15-30% inherent moisture by weight and are non-coking (undergo little swelling upon heating). The heat content of sub-bituminous coals range from 8300 to 11,500 BTu/ lb or 19.3 to 26.7 M J/ kg. Their relatively low density and high water content renders some types of sub-bituminous coals susceptible to spontaneous combustion if not packed densely during storage in order to exclude free air flow. Reserves A major source of sub-bituminous coal in the United States is the Powder R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shaft Mining
Shaft mining or shaft sinking is the action of excavating a mine shaft from the top down, where there is initially no access to the bottom. Shaft (civil engineering), Shallow shafts, typically sunk for civil engineering projects, differ greatly in execution method from deep shafts, typically sunk for mining projects. Shaft sinking is one of the most difficult of all mine development methods: restricted space, gravity, groundwater and specialized procedures make the task quite formidable. Shafts may be sunk by conventional drill and blast or mechanised means. Historically, mine shaft sinking has been among the most dangerous of all the mining occupations and the preserve of mining contractors called sinker (mining), sinkers. Today shaft sinking contractors are concentrated in Canada, Germany, China and South Africa. The modern shaft sinking industry is gradually shifting further towards greater mechanisation. Recent innovations in the form of full-face shaft boring (akin to a v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Australia and Ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laramie Formation
The Laramie Formation is a geologic formation of Late Cretaceous (Maastrichtian) age, named by Clarence King in 1876 for exposures in northeastern Colorado, in the United States.King, C. 1876. Report of the Geological Exploration of the Fortieth Parallel. U.S.Geographical and Geological Survey. It was deposited on a coastal plain and in coastal swamps that flanked the Western Interior Seaway. It contains coal, clay and uranium deposits, as well as plant and animal fossils, including dinosaur remains. Stratigraphy and Lithology The Laramie Formation is exposed around the edges of the Denver Basin and ranges from 400–500 feet (120–150 m) on the western side of the basin, and 200–300 feet (60–90 m) thick on the eastern side. It rests conformably on the Fox Hills Sandstone and unconformably underlies the Arapahoe Conglomerate. The formation can be divided into an unnamed lower member containing bedded sandstone, clay and coal; and an unnamed upper member composed predominatel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Room And Pillar
Room and pillar or pillar and stall is a variant of breast stoping. It is a mining system in which the mined material is extracted across a horizontal plane, creating horizontal arrays of rooms and pillars. To do this, "rooms" of ore are dug out while "pillars" of untouched material are left to support the roof overburden. Calculating the size, shape, and position of pillars is a complicated procedure, and is an area of active research. The technique is usually used for relatively flat-lying deposits, such as those that follow a particular stratum. Room and pillar mining can be advantageous because it reduces the risk of surface subsidence compared to other underground mining techniques. It is also advantageous because it can be mechanized, and is relatively simple. However, because significant portions of ore may have to be left behind, recovery and profits can be low. Room and pillar mining was one of the earliest methods used, although with significantly more man-power. The room ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denver
Denver () is a consolidated city and county, the capital, and most populous city of the U.S. state of Colorado. Its population was 715,522 at the 2020 census, a 19.22% increase since 2010. It is the 19th-most populous city in the United States and the fifth most populous state capital. It is the principal city of the Denver–Aurora–Lakewood, CO Metropolitan Statistical Area and the first city of the Front Range Urban Corridor. Denver is located in the Western United States, in the South Platte River Valley on the western edge of the High Plains just east of the Front Range of the Rocky Mountains. Its downtown district is immediately east of the confluence of Cherry Creek and the South Platte River, approximately east of the foothills of the Rocky Mountains. It is named after James W. Denver, a governor of the Kansas Territory. It is nicknamed the ''Mile High City'' because its official elevation is exactly one mile () above sea level. The 105th meridian we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
David Moffat
David Halliday Moffat (July 22, 1839 – March 18, 1911) was an American financier and industrialist. Moffat was one of Denver's most important financiers and industrialists in late 19th and early 20th century Colorado, and he was responsible for the development of the Middle Park area. He served as president, treasurer and as a board member of railroads, banks and city government posts. Over the years he had claims to over one hundred Colorado mines and nine railroads. Moffat died on March 18, 1911 in New York City at the age of seventy-three. Some had said that he had vainly spent fourteen million dollars on the dream of a railroad directly west from Denver. The Denver, Northwestern & Pacific Railway had cost him $75,000 a mile, and Rollins Pass had cost him the rest of his fortune. He was in New York city trying to raise more money, and was stopped by what would later be learned was the doing of E. H. Harriman and George Jay Gould I. He was one of the greatest threats they h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xcel Energy
Xcel Energy Inc. is an American utility holding company based in Minneapolis, Minnesota, serving more than 3.7 million electric customers and 2.1 million natural gas customers in Colorado, Texas, and New Mexico in 2019. It consists of four operating subsidiaries: Northern States Power-Minnesota, Northern States Power-Wisconsin, Public Service Company of Colorado, and Southwestern Public Service Co. In December 2018, Xcel Energy announced it would deliver 100 percent clean, carbon-free electricity by 2050, with an 80 percent carbon reduction by 2035 (from 2005 levels). This makes Xcel the first major US utility to set such a goal. History Xcel Energy was built on three companies: Minneapolis-based Northern States Power Company (NSP), Denver-based Public Service Company of Colorado (PSCo), and Amarillo-based Southwestern Public Service (SPS). Southwestern Public Service Co. (SPS) dates its origins to 1904 and the Pecos Valley in New Mexico when Maynard Gunsell received an elec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unincorporated Communities In Jefferson County, Colorado
Unincorporated may refer to: * Unincorporated area, land not governed by a local municipality * Unincorporated entity, a type of organization * Unincorporated territories of the United States, territories under U.S. jurisdiction, to which Congress has determined that only select parts of the U.S. Constitution apply * Unincorporated association Unincorporated associations are one vehicle for people to cooperate towards a common goal. The range of possible unincorporated associations is nearly limitless, but typical examples are: :* An amateur football team who agree to hire a pitch onc ..., also known as voluntary association, groups organized to accomplish a purpose * ''Unincorporated'' (album), a 2001 album by Earl Harvin Trio {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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