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Mining
Mining is the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein, seam, reef, or placer deposit. The exploitation of these deposits for raw material is based on the economic viability of investing in the equipment, labor, and energy required to extract, refine and transport the materials found at the mine to manufacturers who can use the material. Ores recovered by mining include metals, coal, oil shale, gemstones, limestone, chalk, dimension stone, rock salt, potash, gravel, and clay. Mining is required to obtain most materials that cannot be grown through agricultural processes, or feasibly created artificially in a laboratory or factory. Mining in a wider sense includes extraction of any non-renewable resource such as petroleum, natural gas, or even water. Modern mining processes involve prospecting for ore bodies, analysis of the profit potential of a proposed mine, extraction of the desire ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal Mining
Coal mining is the process of extracting coal from the ground. Coal is valued for its energy content and since the 1880s has been widely used to generate electricity. Steel and cement industries use coal as a fuel for extraction of iron from iron ore and for cement production. In the United Kingdom and South Africa, a coal mine and its structures are a colliery, a coal mine is called a 'pit', and the above-ground structures are a ' pit head'. In Australia, "colliery" generally refers to an underground coal mine. Coal mining has had many developments in recent years, from the early days of men tunneling, digging and manually extracting the coal on carts to large open-cut and longwall mines. Mining at this scale requires the use of draglines, trucks, conveyors, hydraulic jacks and shearers. The coal mining industry has a long history of significant negative environmental impacts on local ecosystems, health impacts on local communities and workers, and contributes heavily ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal
Coal is a combustible black or brownish-black sedimentary rock, formed as stratum, rock strata called coal seams. Coal is mostly carbon with variable amounts of other Chemical element, elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal is formed when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal originate in former wetlands called coal forests that covered much of the Earth's tropical land areas during the late Carboniferous (Pennsylvanian (geology), Pennsylvanian) and Permian times. Many significant coal deposits are younger than this and originate from the Mesozoic and Cenozoic eras. Coal is used primarily as a fuel. While coal has been known and used for thousands of years, its usage was limited until the Industrial Revolution. With the invention of the steam engine, coal consumption increased. In 2020, coal supplied about a quarter of the world's primary energ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lode
In geology, a lode is a deposit of metalliferous ore that fills or is embedded in a fissure (or crack) in a rock formation or a vein of ore that is deposited or embedded between layers of rock. The current meaning (ore vein) dates from the 17th century, being an expansion of an earlier sense of a "channel, watercourse" in late Middle English, which in turn is from the 11th-century meaning of ''lode'' as a ‘course, way’. The generally accepted hydrothermal model of lode deposition posits that metals dissolved in hydrothermal solutions (hot spring fluids) deposit the gold or other metallic minerals inside the fissures in the pre-existing rocks. Lode deposits are distinguished primarily from placer deposits, where the ore has been eroded out from its original depositional environment and redeposited by sedimentation. A third process for ore deposition is as an evaporite. A stringer lode is one in which the rock is so permeated by small veinlets that rather than mining t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartz Reef Mining
Quartz reef mining is a type of gold mining in "reefs" (veins) of quartz. Quartz is one of the most common minerals in the earth's crust, and most quartz veins do not carry gold, but those that have gold are avidly hunted by prospectors. In the shallow, oxidized zones of quartz reef deposits, the gold occurs in its metallic state, and is easily recovered with simple equipment. Quartz reef mining played an important role in 19th century gold-mining districts such as Bendigo, Victoria, Central Otago in New Zealand, and the California mother lode. Mining Mining the ore usually required mine shafts sunk to mine quartz from the reefs, sometimes deep underground. Horizontal tunnels called drifts were dug out from the shaft at different levels to find the gold-bearing rock. All the ore was hoisted to the surface for processing. Water had to be removed by pumping. Big hoisting engines were installed to hoist lifts and buckets up the shafts. On the surface above the shaft stands a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extractivism
Extractivism is the process of extracting natural resources from the Earth to sell on the world market. It exists in an economy that depends primarily on the extraction or removal of natural resources that are considered valuable for exportation worldwide. Some examples of resources that are obtained through extraction include gold, diamonds, lumber and oil. This economic model has become popular in many Latin American countries but is becoming increasingly prominent in other regions as well. Many factors are involved in the process of extractivism. These include but are not limited to community members, transnational corporations (TNCs) and the government. Trends have demonstrated that countries do not often extract their own resources; extraction is often led from abroad. These interactions have contributed to extractivism being rooted in the hegemonic order of global capitalism. Extractivism is controversial because it exists at the intersection where economic growth and environ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placer Deposit
In geology, a placer deposit or placer is an accumulation of valuable minerals formed by gravity separation from a specific source rock during sedimentary processes. The name is from the Spanish language, Spanish word ''placer'', meaning "alluvium, alluvial sand". Placer mining is an important source of gold, and was the main technique used in the early years of many gold rushes, including the California Gold Rush. Types of placer deposits include alluvium, eluvium, beach placers, aeolian placers and paleo-placers. Placer materials must be both dense and resistant to weathering processes. To accumulate in placers, mineral particles must have a specific gravity above 2.58. Placer environments typically contain black sand, a conspicuous shiny black mixture of iron oxides, mostly magnetite with variable amounts of ilmenite and hematite. Valuable mineral components often occurring with black sands are monazite, rutile, zircon, chromite, wolframite, and cassiterite. Early mining oper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oil Shale
Oil shale is an organic-rich fine-grained sedimentary rock containing kerogen (a solid mixture of organic chemical compounds) from which liquid hydrocarbons can be produced. In addition to kerogen, general composition of oil shales constitutes inorganic substance and bitumens. Based on their deposition environment, oil shales are classified as marine, lacustrine and terrestrial oil shales. Oil shales differ from oil-''bearing'' shales, shale deposits that contain petroleum ( tight oil) that is sometimes produced from drilled wells. Examples of oil-''bearing'' shales are the Bakken Formation, Pierre Shale, Niobrara Formation, and Eagle Ford Formation. Accordingly, shale oil produced from oil shale should not be confused with tight oil, which is also frequently called shale oil. Deposits of oil shale occur around the world, including major deposits in the United States. A 2016 estimate of global deposits set the total world resources of oil shale equivalent of of oil in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prospecting
Prospecting is the first stage of the geological analysis (followed by exploration) of a territory. It is the search for minerals, fossils, precious metals, or mineral specimens. It is also known as fossicking. Traditionally prospecting relied on direct observation of mineralization in rock outcrops or in sediments. Modern prospecting also includes the use of geologic, geophysical, and geochemical tools to search for anomalies which can narrow the search area. Once an anomaly has been identified and interpreted to be a potential prospect direct observation can then be focused on this area. In some areas a prospector must also make claims, meaning they must erect posts with the appropriate placards on all four corners of a desired land they wish to prospect and register this claim before they may take samples. In other areas publicly held lands are open to prospecting without staking a mining claim. Historical methods The traditional methods of prospecting involved comb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite, a closely related rock, which contains a high percentage of the mineral dolomite, . ''Magnesian limestone'' is an obsolete and poorly-defined term used variously for dolomite, for lime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-renewable Resource
A non-renewable resource (also called a finite resource) is a natural resource that cannot be readily replaced by natural means at a pace quick enough to keep up with consumption. An example is carbon-based fossil fuels. The original organic matter, with the aid of heat and pressure, becomes a fuel such as oil or gas. Earth minerals and metal ores, fossil fuels (coal, petroleum, natural gas) and groundwater in certain aquifers are all considered non-renewable resources, though individual elements are always conserved (except in nuclear reactions, nuclear decay or atmospheric escape). Conversely, resources such as timber (when harvested sustainably) and wind (used to power energy conversion systems) are considered renewable resources, largely because their localized replenishment can occur within time frames meaningful to humans as well. Earth minerals and metal ores Earth minerals and metal ores are examples of non-renewable resources. The metals themselves are pres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potash
Potash () includes various mined and manufactured salts that contain potassium in water- soluble form.Potash USGS 2008 Minerals Yearbook The name derives from ''pot ash'', plant ashes or wood ash soaked in water in a pot, the primary means of manufacturing potash before the Industrial Era. The word '''' is derived from ''potash''. Potash is produced worldwide in amounts exceeding 90 million s (40 mil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulphur Mining At Kawah Ijen 3
Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula S8. Elemental sulfur is a bright yellow, crystalline solid at room temperature. Sulfur is the tenth most abundant element by mass in the universe and the fifth most on Earth. Though sometimes found in pure, native form, sulfur on Earth usually occurs as sulfide and sulfate minerals. Being abundant in native form, sulfur was known in ancient times, being mentioned for its uses in ancient India, ancient Greece, China, and ancient Egypt. Historically and in literature sulfur is also called brimstone, which means "burning stone". Today, almost all elemental sulfur is produced as a byproduct of removing sulfur-containing contaminants from natural gas and petroleum.. Downloahere The greatest commercial use of the element is the production of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
