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Drift Mine
Drift mining is either the mining of an ore deposit by Underground mining (hard rock), underground methods, or the working of coal seams accessed by adits driven into the surface outcrop of the coal bed. A drift mine is an underground mine in which the entry or access is above water level and generally on the slope of a hill, driven horizontally into the ore seam. Drift is a more general mining term, meaning a near-horizontal passageway in a mine, following the bed (of coal, for instance) or vein of ore. A drift may or may not intersect the ground surface. A drift follows the vein, as distinguished from a crosscut that intersects it, or a level or gallery, which may do either. All horizontal or subhorizontal development openings made in a mine have the generic name of drift. These are simply tunnels made in the rock, with a size and shape depending on their use—for example, haulage, ventilation, or exploration. Historical US drift mining (coal) Colorado The Boulder-Weld ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mining
Mining is the Resource extraction, extraction of valuable geological materials and minerals from the surface of the Earth. Mining is required to obtain most materials that cannot be grown through agriculture, agricultural processes, or feasibly created Chemical synthesis, artificially in a laboratory or factory. Ores recovered by mining include Metal#Extraction, metals, coal, oil shale, gemstones, limestone, chalk mining, chalk, dimension stone, rock salt, potash, gravel, and clay. The ore must be a rock or mineral that contains valuable constituent, can be extracted or mined and sold for profit. Mining in a wider sense includes extraction of any non-renewable resource such as petroleum, natural gas, or even fossil water, water. Modern mining processes involve prospecting for ore bodies, analysis of the profit potential of a proposed mine, extraction of the desired materials, and final mine reclamation, reclamation or restoration of the land after the mine is closed. Mining ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nome, Alaska
Nome (; , , also ''Sitŋazuaq'', ''Siqnazuaq'') is a city in the Nome Census Area, Alaska, Nome Census Area in the Unorganized Borough, Alaska, Unorganized Borough of the US state of Alaska. The city is located on the southern Seward Peninsula coast on Norton Sound of the Bering Sea. It had a population of 3,699 in 2020, up from 3,598 in 2010. Nome was incorporation (municipal government), incorporated on April 9, 1901. It was once the most-populous city in Alaska. Nome lies within the region of the Bering Straits Native Corporation, which is headquartered in Nome. Prior to being settled by non-indigenous people, the area around Nome was home to Iñupiat natives. The area came to world attention in 1898, when three Nordic-Americans discovered gold on the ocean shores of Nome, prompting the Nome Gold Rush. Within a year, the area became popular among miners of European descent, who built and incorporated the city. Nome quickly reached a population of 10,000 or greater. Gold mining ... [...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 mining 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overburden
In mining, overburden (also called waste or spoil) is the material that lies above an area that lends itself to economical exploitation, such as the rock, soil, and ecosystem that lies above a coal seam or ore body. Overburden is distinct from tailings, the material that remains after economically valuable components have been extracted from the generally finely milled ore. Overburden is removed during surface mining, but is typically not contaminated with toxic components. Overburden may also be used to restore an exhausted mining site during reclamation. Interburden is material that lies between two areas of economic interest, such as the material separating coal seams within strata.Peng, Syd S. (1986) ''Coal Mine Ground Control'' (2nd edition), Wiley, New York, page 303, Analogous uses Overburden is also used for all soil and ancillary material above the bedrock horizon in a given area. By analogy, overburden is also used to describe the soil and other material that lies a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oroville, California
Oroville (''Oro'', Spanish for "Gold" and ''Ville'', French for "town") is a city in and the county seat of Butte County, California, United States. Its population was 15,506 at the 2010 census, up from 13,004 in the 2000 census. After the 2018 Camp Fire that destroyed much of the town of Paradise In religion and folklore, paradise is a place of everlasting happiness, delight, and bliss. Paradisiacal notions are often laden with pastoral imagery, and may be cosmogonical, eschatological, or both, often contrasted with the miseries of human ..., Oroville's population increased as many people who lost their homes moved there. The 2020 United States census, 2020 census recorded Oroville's population as 20,042. Oroville is considered the gateway to Lake Oroville and Feather River recreational areas. The Berry Creek Rancheria of Maidu Indians of California is headquartered in Oroville. Oroville is adjacent to California State Route 70, State Route 70 and in close proximity to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feather River
The Feather River is the principal tributary of the Sacramento River, in the Sacramento Valley of Northern California. The river's main stem is about long. Its length to its most distant headwater tributary is just over . The main stem Feather River begins in Lake Oroville, where its four long tributary forks join—the South Fork, Middle Fork, North Fork, and West Branch Feather Rivers. These and other tributaries drain part of the northern Sierra Nevada, and the extreme southern Cascades, as well as a small portion of the Sacramento Valley. The total drainage basin is about , with approximately above Lake Oroville. The Feather River and its forks were a center of gold mining during the 19th century. Since the 1960s, the river has provided water to central and southern California, as the main source of water for the California State Water Project. Its water is also used for hydroelectricity generation. The average annual flow of the Feather River is more than . The Feath ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sacramento River
The Sacramento River () is the principal river of Northern California in the United States and is the largest river in California. Rising in the Klamath Mountains, the river flows south for before reaching the Sacramento–San Joaquin River Delta and San Francisco Bay. The river drains about in 19 California County (United States), counties, mostly within the fertile agricultural region bounded by the California Coast Ranges, Coast Ranges and Sierra Nevada known as the Sacramento Valley, but also extending as far as the volcanic plateaus of Northeastern California. Historically, its watershed has reached as far north as south-central Oregon where the now, primarily, endorheic basin, endorheic (closed) Goose Lake (Oregon-California), Goose Lake rarely experiences southerly outflow into the Pit River, the most northerly tributary of the Sacramento. The Sacramento and its wide natural floodplain were once abundant in fish and other aquatic creatures, notably one of the southernm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lorenzo Sawyer
Lorenzo Sawyer (May 23, 1820 – September 7, 1891) was an American lawyer and judge who was appointed to the Supreme Court of California in 1860 and served as the ninth Chief Justice of California from 1868 to 1870. He served as a United States circuit judge of the United States Circuit Courts for the Ninth Circuit and of the United States Court of Appeals for the Ninth Circuit. He is best known for handing down the verdict in the case of ''Woodruff v. North Bloomfield Gravel Mining Company;'' his verdict is frequently referred to as the "Sawyer Decision." Early years Sawyer was born on a farm in Le Roy, New York, Le Roy, New York (state), New York the eldest of six children. He worked on the farm during the summer and attended the district school in winter. At the age of fifteen he attended, for a short time, a high school at Watertown, New York, Watertown, New York, called the Black River Institute, where he became interested in the law. In 1837, having reached the age of seve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placer Mining
Placer mining () is the mining of stream bed deposits for minerals. This may be done by open-pit mining or by various surface excavating equipment or tunneling equipment. Placer mining is frequently used for precious metal deposits (particularly gold) and gemstones, both of which are often found in alluvial deposits—deposits of sand and gravel in modern or ancient stream beds, or occasionally glacial deposits. The metal or gemstones, having been moved by stream flow from an original source such as a vein, are typically only a minuscule portion of the total deposit. Since gems and heavy metals like gold are considerably denser than sand, they tend to accumulate at the base of placer deposits. Placer deposits can be as young as a few years old, such as the Canadian Queen Charlotte beach gold placer deposits, or billions of years old like the Elliot Lake uranium paleoplacer within the Huronian Supergroup in Canada. The containing material in an alluvial placer mine may be too lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bell Pit
A bell pit is a primitive method of mining coal, iron ore, or other minerals lying near the surface. Operation A shaft is sunk to reach the mineral which is excavated by miners, transported to the surface by a winch, and removed by means of a bucket, much like a well. The bottom of the shaft is enlarged and a sloping roof is created as the desired mineral and surrounding rock is removed – giving its name because the pit in cross section resembles a bell. Typically, no supports were used, and mining continued outwards until the cavity became too dangerous or collapsed at which point another mine was started, often in close proximity. Example and illustrated description This type of mine was in use in prehistoric times, the Middle Ages, and a few continued in use until the early 20th century in the region around Ford, Northumberland. Such pits are common at prehistoric flint working sites such as Grime's Graves in Norfolk and also in the coal mining areas of Yorkshire, the For ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wales
Wales ( ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by the Irish Sea to the north and west, England to the England–Wales border, east, the Bristol Channel to the south, and the Celtic Sea to the south-west. , it had a population of 3.2 million. It has a total area of and over of Coastline of Wales, coastline. It is largely mountainous with its higher peaks in the north and central areas, including Snowdon (), its highest summit. The country lies within the Temperate climate, north temperate zone and has a changeable, Oceanic climate, maritime climate. Its capital and largest city is Cardiff. A distinct Culture of Wales, Welsh culture emerged among the Celtic Britons after the End of Roman rule in Britain, Roman withdrawal from Britain in the 5th century, and Wales was briefly united under Gruffudd ap Llywelyn in 1055. After over 200 years of war, the Conquest of Wales by Edward I, conquest of Wales by King Edward I o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
