1.
Coal mining
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Coal mining is the process of extracting coal from the ground. Coal is valued for its 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, in the United Kingdom and South Africa a coal mine and its structures are a colliery, a coal mine a pit, the above-ground structures the pit head. In Australia, colliery generally refers to a coal mine. In the United States colliery has been used to describe a coal mine operation, Coal mining has had many developments over the recent years, from the early days of men tunnelling, digging and manually extracting the coal on carts, to large open cut and long wall mines. Mining at this scale requires the use of draglines, trucks, conveyors, hydraulic jacks, small-scale mining of surface deposits dates back thousands of years. For example, in Roman Britain, the Romans were exploiting most of the major coalfields by the late 2nd century AD. The Industrial Revolution, which began in Britain in the 18th century and later spread to continental Europe, international trade expanded rapidly when coal-fed steam engines were built for the railways and steamships. Until the late nineteenth century coal was mined using a pick and shovel. Coal-cutting machines were introduced in the 1880s, by 1912, surface mining was conducted with steam shovels designed for coal mining. The most economical method of extraction from coal seams depends on the depth and quality of the seams. Coal mining processes are differentiated by whether they operate on the surface or underground, many coals extracted from both surface and underground mines require washing in a coal preparation plant. Surface mining and deep underground mining are the two methods of mining. Coal that occurs at depths of 180 to 300 ft are usually deep mined, for example, some western U. S. coal that occur at depths in excess of 200 ft are mined by the open pit methods, due to thickness of the seam 60–90 feet. Coals occurring below 300 ft are usually deep mined, However, there are open pit mining operations working on coal seams up to 1000–1500 feet below ground level, for instance Tagebau Hambach in Germany. When coal seams are near the surface, it may be economical to extract the coal using open cut mining methods, open cast coal mining recovers a greater proportion of the coal deposit than underground methods, as more of the coal seams in the strata may be exploited. In this mining method, explosives are first used in order to break through the surface or overburden, the overburden is then removed by draglines or by shovel and truck. Once the coal seam is exposed, it is drilled, fractured, the coal is then loaded onto large trucks or conveyors for transport to either the coal preparation plant or directly to where it will be used
2.
Wyoming
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Wyoming /waɪˈoʊmɪŋ/ is a state in the mountain region of the western United States. The state is the tenth largest by area, the least populous, Wyoming is bordered on the north by Montana, on the east by South Dakota and Nebraska, on the south by Colorado, on the southwest by Utah, and on the west by Idaho. Cheyenne is the capital and the most populous city in Wyoming, the state population was estimated at 586,107 in 2015, which is less than the population of 31 of the largest U. S. cities. The Crow, Arapaho, Lakota, and Shoshone were some of the inhabitants of the region. Southwestern Wyoming was included in the Spanish Empire and then Mexican territory until it was ceded to the United States in 1848 at the end of the Mexican–American War. The region acquired the name Wyoming when a bill was introduced to Congress in 1865 to provide a government for the territory of Wyoming. The territory was named after the Wyoming Valley in Pennsylvania, with the name ultimately being derived from the Munsee word xwé, wamənk, the mineral extraction industry—especially coal, oil, natural gas, and trona—along with the travel and tourism sector are the main drivers behind Wyomings economy. Agriculture has historically been an important component of the economy with the main commodities being livestock, hay, sugar beets, grain. The climate is generally semi-arid and continental, being drier and windier in comparison to the rest of the United States, except for the 1964 election, Wyoming has been a politically conservative state since the 1950s, with the Republican party winning every presidential election. Wyoming is one of three states to have borders along only straight latitudinal and longitudinal lines, rather than being defined by natural landmarks. Wyoming is bordered on the north by Montana, on the east by South Dakota and Nebraska, on the south by Colorado, on the southwest by Utah, and on the west by Idaho. It is the tenth largest state in the United States in total area, from the north border to the south border it is 276 miles, and from the east to the west border is 365 miles at its south end and 342 miles at the north end. The Great Plains meet the Rocky Mountains in Wyoming, the state is a great plateau broken by many mountain ranges. Surface elevations range from the summit of Gannett Peak in the Wind River Mountain Range, at 13,804 feet, to the Belle Fourche River valley in the states northeast corner, at 3,125 feet. In the northwest are the Absaroka, Owl Creek, Gros Ventre, Wind River, in the north central are the Big Horn Mountains, in the northeast, the Black Hills, and in the southern region the Laramie, Snowy and Sierra Madre ranges. The Snowy Range in the central part of the state is an extension of the Colorado Rockies in both geology and appearance. The Wind River Range in the west central part of the state is remote and includes more than 40 mountain peaks in excess of 13,000 ft tall in addition to Gannett Peak, the highest peak in the state. The Big Horn Mountains in the central portion are somewhat isolated from the bulk of the Rocky Mountains
3.
United States
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Forty-eight of the fifty states and the federal district are contiguous and located in North America between Canada and Mexico. The state of Alaska is in the northwest corner of North America, bordered by Canada to the east, the state of Hawaii is an archipelago in the mid-Pacific Ocean. The U. S. territories are scattered about the Pacific Ocean, the geography, climate and wildlife of the country are extremely diverse. At 3.8 million square miles and with over 324 million people, the United States is the worlds third- or fourth-largest country by area, third-largest by land area. It is one of the worlds most ethnically diverse and multicultural nations, paleo-Indians migrated from Asia to the North American mainland at least 15,000 years ago. European colonization began in the 16th century, the United States emerged from 13 British colonies along the East Coast. Numerous disputes between Great Britain and the following the Seven Years War led to the American Revolution. On July 4,1776, during the course of the American Revolutionary War, the war ended in 1783 with recognition of the independence of the United States by Great Britain, representing the first successful war of independence against a European power. The current constitution was adopted in 1788, after the Articles of Confederation, the first ten amendments, collectively named the Bill of Rights, were ratified in 1791 and designed to guarantee many fundamental civil liberties. During the second half of the 19th century, the American Civil War led to the end of slavery in the country. By the end of century, the United States extended into the Pacific Ocean. The Spanish–American War and World War I confirmed the status as a global military power. The end of the Cold War and the dissolution of the Soviet Union in 1991 left the United States as the sole superpower. The U. S. is a member of the United Nations, World Bank, International Monetary Fund, Organization of American States. The United States is a developed country, with the worlds largest economy by nominal GDP. It ranks highly in several measures of performance, including average wage, human development, per capita GDP. While the U. S. economy is considered post-industrial, characterized by the dominance of services and knowledge economy, the United States is a prominent political and cultural force internationally, and a leader in scientific research and technological innovations. In 1507, the German cartographer Martin Waldseemüller produced a map on which he named the lands of the Western Hemisphere America after the Italian explorer and cartographer Amerigo Vespucci
4.
Coal
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Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure. Coal is composed primarily of carbon, along with quantities of other elements, chiefly hydrogen, sulfur, oxygen. A fossil fuel, coal forms when plant matter is converted into peat, which in turn is converted into lignite, then sub-bituminous coal, after that bituminous coal. This involves biological and geological processes that take place over time, throughout history, coal has been used as an energy resource, primarily burned for the production of electricity and heat, and is also used for industrial purposes, such as refining metals. Coal is the largest source of energy for the generation of electricity worldwide, the extraction of coal, its use in energy production and its byproducts are all associated with environmental and health effects including climate change. Coal is extracted from the ground by coal mining, since 1983, the worlds top coal producer has been China. In 2015 China produced 3,747 million tonnes of coal –47. 7% of 7,861 million tonnes world coal production, in 2015 other large producers were United States, India, European Union and Australia. The word originally took the col in Old English, from Proto-Germanic *kula. In Old Turkic languages, kül is ash, cinders, öčür is quench, the compound charcoal in Turkic is öčür kül, literally quenched ashes, cinders, coals with elided anlaut ö- and inflection affixes -ülmüş. At various times in the geologic past, the Earth had dense forests in low-lying wetland areas, due to natural processes such as flooding, these forests were buried underneath soil. As more and more soil deposited over them, they were compressed, the temperature also rose as they sank deeper and deeper. As the process continued the plant matter was protected from biodegradation and oxidation and this trapped the carbon in immense peat bogs that were eventually covered and deeply buried by sediments. Under high pressure and high temperature, dead vegetation was slowly converted to coal, as coal contains mainly carbon, the conversion of dead vegetation into coal is called carbonization. The wide, shallow seas of the Carboniferous Period provided ideal conditions for coal formation, the exception is the coal gap in the Permian–Triassic extinction event, where coal is rare. Coal is known from Precambrian strata, which predate land plants — this coal is presumed to have originated from residues of algae, in its dehydrated form, peat is a highly effective absorbent for fuel and oil spills on land and water. It is also used as a conditioner for soil to make it able to retain. Lignite, or brown coal, is the lowest rank of coal, jet, a compact form of lignite, is sometimes polished and has been used as an ornamental stone since the Upper Palaeolithic
5.
Earth
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Earth, otherwise known as the World, or the Globe, is the third planet from the Sun and the only object in the Universe known to harbor life. It is the densest planet in the Solar System and the largest of the four terrestrial planets, according to radiometric dating and other sources of evidence, Earth formed about 4.54 billion years ago. Earths gravity interacts with objects in space, especially the Sun. During one orbit around the Sun, Earth rotates about its axis over 365 times, thus, Earths axis of rotation is tilted, producing seasonal variations on the planets surface. The gravitational interaction between the Earth and Moon causes ocean tides, stabilizes the Earths orientation on its axis, Earths lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earths surface is covered with water, mostly by its oceans, the remaining 29% is land consisting of continents and islands that together have many lakes, rivers and other sources of water that contribute to the hydrosphere. The majority of Earths polar regions are covered in ice, including the Antarctic ice sheet, Earths interior remains active with a solid iron inner core, a liquid outer core that generates the Earths magnetic field, and a convecting mantle that drives plate tectonics. Within the first billion years of Earths history, life appeared in the oceans and began to affect the Earths atmosphere and surface, some geological evidence indicates that life may have arisen as much as 4.1 billion years ago. Since then, the combination of Earths distance from the Sun, physical properties, in the history of the Earth, biodiversity has gone through long periods of expansion, occasionally punctuated by mass extinction events. Over 99% of all species that lived on Earth are extinct. Estimates of the number of species on Earth today vary widely, over 7.4 billion humans live on Earth and depend on its biosphere and minerals for their survival. Humans have developed diverse societies and cultures, politically, the world has about 200 sovereign states, the modern English word Earth developed from a wide variety of Middle English forms, which derived from an Old English noun most often spelled eorðe. It has cognates in every Germanic language, and their proto-Germanic root has been reconstructed as *erþō, originally, earth was written in lowercase, and from early Middle English, its definite sense as the globe was expressed as the earth. By early Modern English, many nouns were capitalized, and the became the Earth. More recently, the name is simply given as Earth. House styles now vary, Oxford spelling recognizes the lowercase form as the most common, another convention capitalizes Earth when appearing as a name but writes it in lowercase when preceded by the. It almost always appears in lowercase in colloquial expressions such as what on earth are you doing, the oldest material found in the Solar System is dated to 4. 5672±0.0006 billion years ago. By 4. 54±0.04 Gya the primordial Earth had formed, the formation and evolution of Solar System bodies occurred along with the Sun
6.
Mineral
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A mineral is a naturally occurring chemical compound, usually of crystalline form and abiogenic in origin. A mineral has one specific chemical composition, whereas a rock can be an aggregate of different minerals or mineraloids, the study of minerals is called mineralogy. There are over 5,300 known mineral species, over 5,070 of these have been approved by the International Mineralogical Association, the silicate minerals compose over 90% of the Earths crust. The diversity and abundance of species is controlled by the Earths chemistry. Silicon and oxygen constitute approximately 75% of the Earths crust, which translates directly into the predominance of silicate minerals, minerals are distinguished by various chemical and physical properties. Differences in chemical composition and crystal structure distinguish the various species, changes in the temperature, pressure, or bulk composition of a rock mass cause changes in its minerals. Minerals can be described by their various properties, which are related to their chemical structure. Common distinguishing characteristics include crystal structure and habit, hardness, lustre, diaphaneity, colour, streak, tenacity, cleavage, fracture, parting, more specific tests for describing minerals include magnetism, taste or smell, radioactivity and reaction to acid. Minerals are classified by key chemical constituents, the two dominant systems are the Dana classification and the Strunz classification, the silicate class of minerals is subdivided into six subclasses by the degree of polymerization in the chemical structure. All silicate minerals have a unit of a 4− silica tetrahedron—that is, a silicon cation coordinated by four oxygen anions. These tetrahedra can be polymerized to give the subclasses, orthosilicates, disilicates, cyclosilicates, inosilicates, phyllosilicates, other important mineral groups include the native elements, sulfides, oxides, halides, carbonates, sulfates, and phosphates. The first criterion means that a mineral has to form by a natural process, stability at room temperature, in the simplest sense, is synonymous to the mineral being solid. More specifically, a compound has to be stable or metastable at 25 °C, modern advances have included extensive study of liquid crystals, which also extensively involve mineralogy. Minerals are chemical compounds, and as such they can be described by fixed or a variable formula, many mineral groups and species are composed of a solid solution, pure substances are not usually found because of contamination or chemical substitution. Finally, the requirement of an ordered atomic arrangement is usually synonymous with crystallinity, however, crystals are also periodic, an ordered atomic arrangement gives rise to a variety of macroscopic physical properties, such as crystal form, hardness, and cleavage. There have been recent proposals to amend the definition to consider biogenic or amorphous substances as minerals. The formal definition of an approved by the IMA in 1995, A mineral is an element or chemical compound that is normally crystalline. However, if geological processes were involved in the genesis of the compound, Mineral classification schemes and their definitions are evolving to match recent advances in mineral science
7.
Metal
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A metal is a material that is typically hard, opaque, shiny, and has good electrical and thermal conductivity. Metals are generally malleable—that is, they can be hammered or pressed permanently out of shape without breaking or cracking—as well as fusible and ductile, about 91 of the 118 elements in the periodic table are metals, the others are nonmetals or metalloids. Some elements appear in both metallic and non-metallic forms, astrophysicists use the term metal to collectively describe all elements other than hydrogen and helium, the simplest two, in a star. The star fuses smaller atoms, mostly hydrogen and helium, to larger ones over its lifetime. In that sense, the metallicity of an object is the proportion of its matter made up of all chemical elements. Many elements and compounds that are not normally classified as metals become metallic under high pressures, the atoms of metallic substances are typically arranged in one of three common crystal structures, namely body-centered cubic, face-centered cubic, and hexagonal close-packed. In bcc, each atom is positioned at the center of a cube of eight others, in fcc and hcp, each atom is surrounded by twelve others, but the stacking of the layers differs. Some metals adopt different structures depending on the temperature, atoms of metals readily lose their outer shell electrons, resulting in a free flowing cloud of electrons within their otherwise solid arrangement. This provides the ability of metallic substances to easily transmit heat, while this flow of electrons occurs, the solid characteristic of the metal is produced by electrostatic interactions between each atom and the electron cloud. This type of bond is called a metallic bond, Metals are usually inclined to form cations through electron loss, reacting with oxygen in the air to form oxides over various timescales. Examples,4 Na + O2 →2 Na2O2 Ca + O2 →2 CaO4 Al +3 O2 →2 Al2O3, the transition metals are slower to oxidize because they form a passivating layer of oxide that protects the interior. Others, like palladium, platinum and gold, do not react with the atmosphere at all, some metals form a barrier layer of oxide on their surface which cannot be penetrated by further oxygen molecules and thus retain their shiny appearance and good conductivity for many decades. The oxides of metals are generally basic, as opposed to those of nonmetals, exceptions are largely oxides with very high oxidation states such as CrO3, Mn2O7, and OsO4, which have strictly acidic reactions. Painting, anodizing or plating metals are good ways to prevent their corrosion, however, a more reactive metal in the electrochemical series must be chosen for coating, especially when chipping of the coating is expected. Water and the two form an electrochemical cell, and if the coating is less reactive than the coatee. Metals in general have high conductivity, high thermal conductivity. Typically they are malleable and ductile, deforming under stress without cleaving, in terms of optical properties, metals are shiny and lustrous. Sheets of metal beyond a few micrometres in thickness appear opaque, although most metals have higher densities than most nonmetals, there is wide variation in their densities, lithium being the least dense solid element and osmium the densest
8.
Ore
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An ore is a type of rock that contains sufficient minerals with important elements including metals that can be economically extracted from the rock. The ores are extracted from the earth through mining, they are refined to extract the valuable element. The grade or concentration of an ore mineral, or metal, as well as its form of occurrence, will directly affect the costs associated with mining the ore. The cost of extraction must thus be weighed against the value contained in the rock to determine what ore can be processed. Metal ores are generally oxides, sulfides, silicates, or native metals that are not commonly concentrated in the Earths crust, the ores must be processed to extract the metals of interest from the waste rock and from the ore minerals. Ore bodies are formed by a variety of geological processes, the process of ore formation is called ore genesis. An ore deposit is an accumulation of ore and this is distinct from a mineral resource as defined by the mineral resource classification criteria. An ore deposit is one occurrence of a particular ore type, Ore deposits are classified according to various criteria developed via the study of economic geology, or ore genesis. Stratiform arkose-hosted and shale-hosted copper, typified by the Zambian copperbelt and this identifies, early on, whether further investment in estimation and engineering studies is warranted and identifies key risks and areas for further work. This is because the distribution of ores is unequal and dislocated from locations of peak demand. Other, lesser, commodities do not have international clearing houses and benchmark prices and this generally makes determining the price of ores of this nature opaque and difficult. Such metals include lithium, niobium-tantalum, bismuth, antimony and rare earths, most of these commodities are also dominated by one or two major suppliers with >60% of the worlds reserves. The London Metal Exchange aims to add uranium to its list of metals on warrant, the World Bank reports that China was the top importer of ores and metals in 2005 followed by the USA and Japan. Economic geology Mineral resource classification Ore genesis Petrology Froth Flotation Extractive metallurgy DILL, the “chessboard” classification scheme of mineral deposits, Mineralogy and geology from aluminum to zirconium, Earth-Science Reviews, Volume 100, Issue 1-4, June 2010, Pages 1-420
9.
Fossil fuel
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Fossil fuels are fuels formed by natural processes such as anaerobic decomposition of buried dead organisms, containing energy originating in ancient photosynthesis. The age of the organisms and their resulting fossil fuels is typically millions of years, Fossil fuels contain high percentages of carbon and include petroleum, coal, and natural gas. Other commonly used derivatives include kerosene and propane, Fossil fuels range from volatile materials with low carbon, hydrogen ratios like methane, to liquids like petroleum, to nonvolatile materials composed of almost pure carbon, like anthracite coal. Methane can be found in hydrocarbon fields either alone, associated with oil, non-fossil sources in 2006 included nuclear 8. 5%, hydroelectric 6. 3%, and others amounting to 0. 9%. World energy consumption was growing about 2. 3% per year, the use of fossil fuels raises serious environmental concerns. The burning of fossil fuels produces around 21.3 billion tonnes of carbon dioxide per year and it is estimated that natural processes can only absorb about half of that amount, so there is a net increase of 10.65 billion tonnes of atmospheric carbon dioxide per year. Carbon dioxide is a gas that increases radiative forcing and contributes to global warming. A global movement towards the generation of energy is underway to help reduce global greenhouse gas emissions. Over geological time, this matter, mixed with mud. Despite these heat driven transformations, the energy is still photosynthetic in origin. There is a range of organic, or hydrocarbon, compounds in any given fuel mixture. The specific mixture of hydrocarbons gives a fuel its characteristic properties, such as boiling point, melting point, density, viscosity, some fuels like natural gas, for instance, contain only very low boiling, gaseous components. Others such as gasoline or diesel contain much higher boiling components, terrestrial plants, on the other hand, tend to form coal and methane. Many of the coal fields date to the Carboniferous period of Earths history, terrestrial plants also form type III kerogen, a source of natural gas. Fossil fuels are of importance because they can be burned. The use of coal as a fuel predates recorded history, coal was used to run furnaces for the melting of metal ore. Semi-solid hydrocarbons from seeps were also burned in ancient times, commercial exploitation of petroleum, largely as a replacement for oils from animal sources, for use in oil lamps began in the 19th century. Natural gas, once flared-off as an byproduct of petroleum production, is now considered a very valuable resource
10.
Petroleum
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Petroleum is a naturally occurring, yellow-to-black liquid found in geological formations beneath the Earths surface, which is commonly refined into various types of fuels. Components of petroleum are separated using a technique called fractional distillation and it consists of hydrocarbons of various molecular weights and other organic compounds. The name petroleum covers both naturally occurring unprocessed crude oil and petroleum products that are made up of refined crude oil. A fossil fuel, petroleum is formed when large quantities of dead organisms, usually zooplankton and algae, are buried underneath sedimentary rock, Petroleum has mostly been recovered by oil drilling. Drilling is carried out studies of structural geology, sedimentary basin analysis. Petroleum is used in manufacturing a variety of materials. Concern over the depletion of the earths finite reserves of oil, the burning of fossil fuels plays the major role in the current episode of global warming. The word petroleum comes from Greek, πέτρα for rocks and Greek, the term was found in 10th-century Old English sources. It was used in the treatise De Natura Fossilium, published in 1546 by the German mineralogist Georg Bauer, Petroleum, in one form or another, has been used since ancient times, and is now important across society, including in economy, politics and technology. Great quantities of it were found on the banks of the river Issus, ancient Persian tablets indicate the medicinal and lighting uses of petroleum in the upper levels of their society. By 347 AD, oil was produced from bamboo-drilled wells in China, early British explorers to Myanmar documented a flourishing oil extraction industry based in Yenangyaung that, in 1795, had hundreds of hand-dug wells under production. The mythological origins of the oil fields at Yenangyaung, and its hereditary monopoly control by 24 families, Pechelbronn is said to be the first European site where petroleum has been explored and used. The still active Erdpechquelle, a spring where petroleum appears mixed with water has been used since 1498, Oil sands have been mined since the 18th century. In Wietze in lower Saxony, natural asphalt/bitumen has been explored since the 18th century, both in Pechelbronn as in Wietze, the coal industry dominated the petroleum technologies. In 1848 Young set up a small business refining the crude oil, Young eventually succeeded, by distilling cannel coal at a low heat, in creating a fluid resembling petroleum, which when treated in the same way as the seep oil gave similar products. The production of oils and solid paraffin wax from coal formed the subject of his patent dated 17 October 1850. In 1850 Young & Meldrum and Edward William Binney entered into partnership under the title of E. W. Binney & Co. at Bathgate in West Lothian, the worlds first oil refinery was built in 1856 by Ignacy Łukasiewicz. The demand for petroleum as a fuel for lighting in North America, edwin Drakes 1859 well near Titusville, Pennsylvania, is popularly considered the first modern well
11.
Natural gas
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It is formed when layers of decomposing plant and animal matter are exposed to intense heat and pressure under the surface of the Earth over millions of years. The energy that the plants originally obtained from the sun is stored in the form of bonds in the gas. Natural gas is a fuel used as a source of energy for heating, cooking. It is also used as fuel for vehicles and as a feedstock in the manufacture of plastics. Natural gas is found in underground rock formations or associated with other hydrocarbon reservoirs in coal beds. Petroleum is another resource and fossil fuel found in proximity to. Most natural gas was created over time by two mechanisms, biogenic and thermogenic, biogenic gas is created by methanogenic organisms in marshes, bogs, landfills, and shallow sediments. Deeper in the earth, at temperature and pressure, thermogenic gas is created from buried organic material. In petroleum production gas is burnt as flare gas. The World Bank estimates that over 150 cubic kilometers of gas are flared or vented annually. Before natural gas can be used as a fuel, most, Natural gas is often informally referred to simply as gas, especially when compared to other energy sources such as oil or coal. However, it is not to be confused with gasoline, especially in North America, Natural gas was used by the Chinese in about 500 BCE. They discovered a way to transport gas seeping from the ground in crude pipelines of bamboo to where it was used to salt water to extract the salt. The worlds first industrial extraction of gas started at Fredonia, New York. By 2009,66000 km³ had been used out of the total 850000 km³ of estimated remaining reserves of natural gas. An annual increase in usage of 2–3% could result in currently recoverable reserves lasting significantly less, unwanted natural gas was a disposal problem in the active oil fields. If there was not a market for natural gas near the wellhead it was expensive to pipe to the end user. In the 19th century and early 20th century, unwanted gas was burned off at oil fields
12.
Groundwater
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Groundwater is the water present beneath Earths surface in soil pore spaces and in the fractures of rock formations. A unit of rock or a deposit is called an aquifer when it can yield a usable quantity of water. The depth at which pore spaces or fractures and voids in rock become completely saturated with water is called the water table. Groundwater is recharged from, and eventually flows to, the naturally, natural discharge often occurs at springs and seeps. Groundwater is also withdrawn for agricultural, municipal, and industrial use by constructing and operating extraction wells. The study of the distribution and movement of groundwater is hydrogeology, Groundwater is hypothesized to provide lubrication that can possibly influence the movement of faults. It is likely that much of Earths subsurface contains some water, Groundwater may not be confined only to Earth. The formation of some of the landforms observed on Mars may have influenced by groundwater. There is also evidence that water may also exist in the subsurface of Jupiters moon Europa. Groundwater is often cheaper, more convenient and less vulnerable to pollution than surface water, therefore, it is commonly used for public water supplies. For example, groundwater provides the largest source of water storage in the United States. Underground reservoirs contain far more water than the capacity of all surface reservoirs and lakes in the US, many municipal water supplies are derived solely from groundwater. Polluted groundwater is less visible, but more difficult to clean up, than pollution in rivers, Groundwater pollution most often results from improper disposal of wastes on land. An aquifer is a layer of substrate that contains and transmits groundwater. When water can flow directly between the surface and the zone of an aquifer, the aquifer is unconfined. The deeper parts of unconfined aquifers are more saturated since gravity causes water to flow downward. The upper level of this layer of an unconfined aquifer is called the water table or phreatic surface. Below the water table, where in general all pore spaces are saturated with water, is the phreatic zone, substrate with low porosity that permits limited transmission of groundwater is known as an aquitard
13.
Aquifer
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An aquifer is an underground layer of water-bearing permeable rock, rock fractures or unconsolidated materials from which groundwater can be extracted using a water well. The study of flow in aquifers and the characterization of aquifers is called hydrogeology. Related terms include aquitard, which is a bed of low permeability along an aquifer, and aquiclude, if the impermeable area overlies the aquifer, pressure could cause it to become a confined aquifer. Aquifers may occur at various depths and those closer to the surface are not only more likely to be used for water supply and irrigation, but are also more likely to be topped up by the local rainfall. Many desert areas have limestone hills or mountains within them or close to them that can be exploited as groundwater resources, overexploitation can lead to the exceeding of the practical sustained yield, i. e. more water is taken out than can be replenished. The beach provides a model to help visualize an aquifer, if a hole is dug into the sand, very wet or saturated sand will be located at a shallow depth. This hole is a well, the wet sand represents an aquifer. In 2013 large freshwater aquifers were discovered under continental shelves off Australia, China, North America and they contain an estimated half a million cubic kilometers of “low salinity” water that could be economically processed into potable water. The reserves formed when ocean levels were lower and rainwater made its way into the ground in areas that were not submerged until the ice age ended 20,000 years ago. The volume is estimated to be 100x the amount of extracted from other aquifers since 1900. The above diagram indicates typical flow directions in a view of a simple confined or unconfined aquifer system. The system shows two aquifers with one aquitard between them, surrounded by the bedrock aquiclude, which is in contact with a gaining stream, the water table and unsaturated zone are also illustrated. An aquitard is a zone within the earth that restricts the flow of groundwater from one aquifer to another, an aquitard can sometimes, if completely impermeable, be called an aquiclude or aquifuge. Aquitards are composed of layers of clay or non-porous rock with low hydraulic conductivity. Groundwater can be found at every point in the Earths shallow subsurface to some degree. Saturated means the head of the water is greater than atmospheric pressure. The definition of the table is the surface where the pressure head is equal to atmospheric pressure. Unsaturated conditions occur above the table where the pressure head is negative
14.
Chemical element
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A chemical element or element is a species of atoms having the same number of protons in their atomic nuclei. There are 118 elements that have identified, of which the first 94 occur naturally on Earth with the remaining 24 being synthetic elements. There are 80 elements that have at least one stable isotope and 38 that have exclusively radioactive isotopes, iron is the most abundant element making up Earth, while oxygen is the most common element in the Earths crust. Chemical elements constitute all of the matter of the universe. The two lightest elements, hydrogen and helium, were formed in the Big Bang and are the most common elements in the universe. The next three elements were formed mostly by cosmic ray spallation, and are rarer than those that follow. Formation of elements with from 6 to 26 protons occurred and continues to occur in main sequence stars via stellar nucleosynthesis, the high abundance of oxygen, silicon, and iron on Earth reflects their common production in such stars. The term element is used for atoms with a number of protons as well as for a pure chemical substance consisting of a single element. A single element can form multiple substances differing in their structure, when different elements are chemically combined, with the atoms held together by chemical bonds, they form chemical compounds. Only a minority of elements are found uncombined as relatively pure minerals, among the more common of such native elements are copper, silver, gold, carbon, and sulfur. All but a few of the most inert elements, such as gases and noble metals, are usually found on Earth in chemically combined form. While about 32 of the elements occur on Earth in native uncombined forms. For example, atmospheric air is primarily a mixture of nitrogen, oxygen, and argon, the history of the discovery and use of the elements began with primitive human societies that found native elements like carbon, sulfur, copper and gold. Later civilizations extracted elemental copper, tin, lead and iron from their ores by smelting, using charcoal, alchemists and chemists subsequently identified many more, almost all of the naturally occurring elements were known by 1900. Save for unstable radioactive elements with short half-lives, all of the elements are available industrially, almost all other elements found in nature were made by various natural methods of nucleosynthesis. On Earth, small amounts of new atoms are produced in nucleogenic reactions, or in cosmogenic processes. Of the 94 naturally occurring elements, those with atomic numbers 1 through 82 each have at least one stable isotope, Isotopes considered stable are those for which no radioactive decay has yet been observed. Elements with atomic numbers 83 through 94 are unstable to the point that radioactive decay of all isotopes can be detected, the very heaviest elements undergo radioactive decay with half-lives so short that they are not found in nature and must be synthesized
15.
Lumber
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Lumber, or timber is wood that has been processed into beams and planks, a stage in the process of wood production. Lumber may also refer to currently un-needed furniture, as in Lumber room, or an awkward gait, ultimately derived from the look of unfashionable, Lumber may be supplied either rough-sawn, or surfaced on one or more of its faces. Besides pulpwood, rough lumber is the raw material for furniture-making and it is available in many species, usually hardwoods, but it is also readily available in softwoods, such as white pine and red pine, because of their low cost. Lumber is mainly used for structural purposes but has other uses as well. It is classified more commonly as a softwood than as a hardwood, in Australia, Ireland, New Zealand and Britain, the term timber describes sawn wood products, such as floor boards. In the United States and Canada, generally timber describes standing or felled trees, before they are milled into boards, Timber there also describes sawn lumber not less than 5 inches in its smallest dimension. The latter includes the often partly finished lumber used in timber-frame construction, remanufactured lumber is the result of secondary or tertiary processing/cutting of previously milled lumber. Specifically, it is cut for industrial or wood-packaging use. Lumber is cut by ripsaw or resaw to create dimensions that are not usually processed by a primary sawmill, resawing is the splitting of 1-inch through 12-inch hardwood or softwood lumber into two or more thinner pieces of full-length boards. For example, splitting a ten-foot 2×4 into two ten-foot 1×4s is considered resawing, structural lumber may also be produced from recycled plastic and new plastic stock. Its introduction has been opposed by the forestry industry. Blending fiberglass in plastic lumber enhances its strength, durability, logs are converted into timber by being sawn, hewn, or split. Sawing with a rip saw is the most common method, because sawing allows logs of lower quality, with grain and large knots. There are various types of sawing, Plain sawn —A log sawn through without adjusting the position of the log, quarter sawn and rift sawn—These terms have been confused in history but generally mean lumber sawn so the annual rings are reasonably perpendicular to the sides of the lumber. Boxed heart—The pith remains within the piece with some allowance for exposure, heart center—the center core of a log. Free of heart center —A side-cut timber without any pith, free of knots —No knots are present. Dimensional lumber is lumber that is cut to standardized width and depth, carpenters extensively use dimensional lumber in framing wooden buildings. Common sizes include 2×4, 2×6, and 4×4, the length of a board is usually specified separately from the width and depth
16.
Sustainable forest management
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Sustainable forest management is the management of forests according to the principles of sustainable development. Sustainable forest management has to keep the balance between three pillars, ecological, economic and socio-cultural. A number of sets of criteria and indicators have since developed to evaluate the achievement of SFM at the global, regional, country. These were all attempts to codify and provide for independent assessment of the degree to which the objectives of sustainable forest management are being achieved in practice. In 2007, the United Nations General Assembly adopted the Non-Legally Binding Instrument on All Types of Forests, a definition of SFM was developed by the Ministerial Conference on the Protection of Forests in Europe, and has since been adopted by the Food and Agriculture Organization. This balance is critical to the survival of forests, and to the prosperity of forest-dependent communities. For forest managers, sustainably managing a particular forest tract means determining, in a way, how to use it today to ensure similar benefits, health. In most cases, forest managers develop their forest plans in consultation with citizens, businesses, organizations and other interested parties in, the tools and visualization have been recently evolving for better management practices. Because forests and societies are in constant flux, the outcome of sustainable forest management is not a fixed one. What constitutes a sustainably managed forest will change over time as values held by the public change, Criteria and indicators are tools which can be used to conceptualise, evaluate and implement sustainable forest management. Criteria define and characterize the essential elements, as well as a set of conditions or processes, periodically measured indicators reveal the direction of change with respect to each criterion. Criteria and indicators of sustainable forest management are used and many countries produce national reports that assess their progress toward sustainable forest management. There are nine international and regional criteria and indicators initiatives, which involve more than 150 countries. Countries who are members of the same initiative usually agree to produce reports at the same time, within countries, at the management unit level, efforts have also been directed at developing local level criteria and indicators of sustainable forest management. There appears to be growing international consensus on the key elements of sustainable forest management, seven common thematic areas of sustainable forest management have emerged based on the criteria of the nine ongoing regional and international criteria and indicators initiatives. This consensus on common thematic areas effectively provides a common, implicit definition of sustainable forest management, the seven thematic areas were acknowledged by the international forest community at the fourth session of the United Nations Forum on Forests and the 16th session of the Committee on Forestry. The Ecosystem Approach has been prominent on the agenda of the Convention on Biological Diversity since 1995, the CBD definition of the Ecosystem Approach and a set of principles for its application were developed at an expert meeting in Malawi in 1995, known as the Malawi Principles. The definition,12 principles and 5 points of operational guidance were adopted by the fifth Conference of Parties in 2000, application of the ecosystem approach will help to reach a balance of the three objectives of the Convention
17.
Renewable resource
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Renewable resources are a part of Earths natural environment and the largest components of its ecosphere. A positive life cycle assessment is a key indicator of a resources sustainability, definitions of renewable resources may also include agricultural production, as in sustainable agriculture and to an extent water resources. In 1962 Paul Alfred Weiss defined Renewable Resources as, The total range of living organisms providing man with food, fibres, drugs, another type of renewable resources is renewable energy resources. Common sources of energy include solar, geothermal and wind power. Water can be considered a material when carefully controlled usage, treatment. If not, it would become a resource at that location. For example, groundwater is removed from an aquifer at a rate much greater than its very slow natural recharge. Removal of water from the spaces may cause permanent compaction that cannot be renewed. 97. 5% of the water on the Earth is salt water, the remaining unfrozen freshwater is found mainly as groundwater, with only a small fraction present above ground or in the air. Water pollution is one of the concerns regarding water resources. It is estimated that 22% of worldwide water is used in industry, major industrial users include hydroelectric dams, thermoelectric power plants, ore and oil refineries and manufacturing plants. Food is any substance consumed to provide support for the body. Most food has its origin in renewable resources, Food is obtained directly from plants and animals. Wild berries and other fruits, mushrooms, plants, seeds and naturally growing edible resources, still represent a source of nutrition in many countries. In fact many wild animals are dependent on plants and fruits as a source of food. Hunting may not be the first source of meat in the modernised world and it is also the sole source of feeding for wild carnivores. The phrase sustainable agriculture was coined by Australian agricultural scientist Gordon McClymont and it has been defined as an integrated system of plant and animal production practices having a site-specific application that will last over the long term. Expansion of agricultural land reduces biodiversity and contributes to deforestation, although air and sunlight are available everywhere on Earth, crops also depend on soil nutrients and the availability of water
18.
Mining
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Mining is extraction of valuable minerals or other geological materials from the earth usually from an orebody, lode, vein, seam, reef or placer deposits. These deposits form a mineralized package that is of economic interest to the miner, 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 any material that cannot be grown through agricultural processes, Mining in a wider sense includes extraction of any non-renewable resource such as petroleum, natural gas, or even water. Mining of stones and metal has been a human activity since pre-historic times, Mining operations usually create a negative environmental impact, both during the mining activity and after the mine has closed. Hence, most of the nations have passed regulations to decrease the impact. Work safety has long been a concern as well, and modern practices have significantly improved safety in mines, levels of metals recycling are generally low. Unless future end-of-life recycling rates are stepped up, some rare metals may become unavailable for use in a variety of consumer products, due to the low recycling rates, some landfills now contain higher concentrations of metal than mines themselves. Since the beginning of civilization, people have used stone, ceramics and, later and these were used to make early tools and weapons, for example, high quality flint found in northern France, southern England and Poland was used to create flint tools. Flint mines have been found in areas where seams of the stone were followed underground by shafts. The mines at Grimes Graves and Krzemionki are especially famous, other hard rocks mined or collected for axes included the greenstone of the Langdale axe industry based in the English Lake District. The oldest-known mine on archaeological record is the Lion Cave in Swaziland, at this site Paleolithic humans mined hematite to make the red pigment ochre. Mines of an age in Hungary are believed to be sites where Neanderthals may have mined flint for weapons. Ancient Egyptians mined malachite at Maadi, at first, Egyptians used the bright green malachite stones for ornamentations and pottery. Later, between 2613 and 2494 BC, large building projects required expeditions abroad to the area of Wadi Maghareh in order to secure minerals and other resources not available in Egypt itself. Quarries for turquoise and copper were found at Wadi Hammamat, Tura, Aswan and various other Nubian sites on the Sinai Peninsula. Mining in Egypt occurred in the earliest dynasties, the gold mines of Nubia were among the largest and most extensive of any in Ancient Egypt. These mines are described by the Greek author Diodorus Siculus, who mentions fire-setting as one used to break down the hard rock holding the gold. One of the complexes is shown in one of the earliest known maps, the miners crushed the ore and ground it to a fine powder before washing the powder for the gold dust
19.
Crust (geology)
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In geology, the crust is the outermost solid shell of a rocky planet or natural satellite, which is chemically distinct from the underlying mantle. The crust of the Earth is composed of a variety of igneous, metamorphic. The crust is underlain by the mantle, the upper part of the mantle is composed mostly of peridotite, a rock denser than rocks common in the overlying crust. The boundary between the crust and mantle is conventionally placed at the Mohorovičić discontinuity, a boundary defined by a contrast in seismic velocity, the crust occupies less than 1% of Earths volume. The crust of the Earth is of two types, oceanic and continental. The oceanic crust is 5 km to 10 km thick and is composed primarily of basalt, diabase, the continental crust is typically from 30 km to 50 km thick and is mostly composed of slightly less dense rocks than those of the oceanic crust. Some of these less dense rocks, such as granite, are common in the continental crust, both the continental and oceanic crust float on the mantle. Because the continental crust is thicker, it both to greater elevations and greater depth than the oceanic crust. The slightly lower density of continental rock compared to basaltic oceanic rock contributes to the higher relative elevation of the top of the continental crust. As the top of the continental crust reaches elevations higher than that of the oceanic, the temperature of the crust increases with depth, reaching values typically in the range from about 200 °C to 400 °C at the boundary with the underlying mantle. The crust and underlying relatively rigid uppermost mantle make up the lithosphere, because of convection in the underlying plastic upper mantle and asthenosphere, the lithosphere is broken into tectonic plates that move. The temperature increases by as much as 30 °C for every kilometer locally in the part of the crust. Earth has probably always had some form of basaltic crust, in contrast, the bulk of the continental crust is much older. The oldest continental crustal rocks on Earth have ages in the range from about 3.7 to 4, some zircon with age as great as 4.3 billion years has been found in the Narryer Gneiss Terrane. The average age of the current Earths continental crust has been estimated to be about 2.0 billion years, most crustal rocks formed before 2.5 billion years ago are located in cratons. Such old continental crust and the underlying mantle asthenosphere are less dense than elsewhere in Earth, formation of new continental crust is linked to periods of intense orogeny, these periods coincide with the formation of the supercontinents such as Rodinia, Pangaea and Gondwana. The continental crust has a composition similar to that of andesite. The most abundant minerals in Earths continental crust are feldspars, which make up about 41% of the crust by weight, followed by quartz at 12%, Continental crust is enriched in incompatible elements compared to the basaltic ocean crust and much enriched compared to the underlying mantle
20.
Ore genesis
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Various theories of ore genesis explain how the various types of mineral deposits form within the Earths crust. Ore-genesis theories vary depending on the mineral or commodity examined, ore-genesis theories generally involve three components, source, transport or conduit, and trap. Source is required because metal must come from somewhere, and be liberated by some process, trapping is required to concentrate the metal via some physical, chemical, or geological mechanism into a concentration which forms mineable ore. The biggest deposits form when the source is large, the mechanism is efficient. Fractional crystallization, separates ore and non-ore minerals according to their crystallization temperature, as early crystallizing minerals form from magma, they incorporate certain elements, some of which are metals. These crystals may settle onto the bottom of the intrusion, concentrating ore minerals there, chromite and magnetite are ore minerals that form in this way. Liquid immiscibility, sulfide ores containing copper, nickel, or platinum may form from this process, as a magma changes, parts of it may separate from the main body of magma. Two liquids that will not mix are called immiscible, oil, in magmas, sulfides may separate and sink below the silicate-rich part of the intrusion or be injected into the rock surrounding it. These deposits are found in mafic and ultramafic rocks and these processes are the physicochemical phenomena and reactions caused by movement of hydrothermal water within the crust, often as a consequence of magmatic intrusion or tectonic upheavals. The foundations of hydrothermal processes are the source-transport-trap mechanism, metal sources may include a plethora of rocks. However most metals of economic importance are carried as trace elements within rock-forming minerals and this happens because of, incompatibility of the metal with its host mineral, for example zinc in calcite, which favours aqueous fluids in contact with the host mineral during diagenesis. These metal-bearing complexes facilitate transport of metals within aqueous solutions, generally as hydroxides and this process is especially well understood in gold metallogeny where various thiosulfate, chloride, and other gold-carrying chemical complexes. The majority of deposits formed by hydrothermal processes include sulfide minerals. This may occur without much hydrothermal fluid flow, and this is typical of podiform chromite deposits, metamorphic processes also control many physical processes which form the source of hydrothermal fluids, outlined above. Surficial processes are the physical and chemical phenomena which cause concentration of ore material within the regolith and this includes placer deposits, laterite deposits, and residual or eluvial deposits. Ore deposits rarely fit neatly into the categories in which geologists wish to place them, many may be formed by one or more of the basic genesis processes above, creating ambiguous classifications and much argument and conjecture. Often ore deposits are classified after examples of their type, for instance Broken Hill type lead-zinc-silver deposits or Carlin–type gold deposits and this scheme, proposed by Waldemar Lindgren classified hydrothermal deposits as hypothermal, mesothermal, epithermal, and telethermal. Epithermal deposits are hydrothermal ore deposits formed at low temperatures near the Earth´s surface, that fill veins, breccias, the age of formation of epithermal deposits in México is currently being investigated
21.
Plate tectonics
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The theoretical model builds on the concept of continental drift developed during the first few decades of the 20th century. The geoscientific community accepted plate-tectonic theory after seafloor spreading was validated in the late 1950s, the lithosphere, which is the rigid outermost shell of a planet, is broken up into tectonic plates. The Earths lithosphere is composed of seven or eight major plates, where the plates meet, their relative motion determines the type of boundary, convergent, divergent, or transform. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation occur along plate boundaries. The relative movement of the plates typically ranges from zero to 100 mm annually, tectonic plates are composed of oceanic lithosphere and thicker continental lithosphere, each topped by its own kind of crust. Along convergent boundaries, subduction carries plates into the mantle, the material lost is balanced by the formation of new crust along divergent margins by seafloor spreading. In this way, the surface of the lithosphere remains the same. This prediction of plate tectonics is also referred to as the conveyor belt principle, earlier theories, since disproven, proposed gradual shrinking or gradual expansion of the globe. Tectonic plates are able to move because the Earths lithosphere has greater strength than the underlying asthenosphere. Lateral density variations in the result in convection. Plate movement is thought to be driven by a combination of the motion of the seafloor away from the ridge and drag, with downward suction. Another explanation lies in the different forces generated by forces of the Sun. The relative importance of each of these factors and their relationship to other is unclear. The outer layers of the Earth are divided into the lithosphere and asthenosphere and this is based on differences in mechanical properties and in the method for the transfer of heat. Mechanically, the lithosphere is cooler and more rigid, while the asthenosphere is hotter, in terms of heat transfer, the lithosphere loses heat by conduction, whereas the asthenosphere also transfers heat by convection and has a nearly adiabatic temperature gradient. The key principle of plate tectonics is that the lithosphere exists as separate and distinct tectonic plates, Plate motions range up to a typical 10–40 mm/year, to about 160 mm/year. The driving mechanism behind this movement is described below, tectonic lithosphere plates consist of lithospheric mantle overlain by either or both of two types of crustal material, oceanic crust and continental crust. Average oceanic lithosphere is typically 100 km thick, its thickness is a function of its age, as passes, it conductively cools
22.
Tectonic subsidence
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Tectonic subsidence is the sinking of the Earths crust on a large scale, relative to crustal-scale features or the geoid. Three mechanisms are common in the environments in which subsidence occurs, extension. These fault systems allow the region to stretch, while decreasing its thickness. A thinner crust subsides relative to thicker, undeformed crust, lithospheric stretching/thinning during rifting results in regional necking of the lithosphere. The underlying asthenosphere passively rises to replace the thinned mantle lithosphere, subsequently, after the rifting/stretching period ends, this shallow asthenosphere gradually cools back into mantle lithosphere over a period of many tens of millions of years. Because mantle lithosphere is denser than asthenospheric mantle, this cooling causes subsidence and this gradual subsidence due to cooling is known as thermal subsidence. The adding of weight by sedimentation from erosion or orogenic processes, or loading, causes crustal depression, sediments accumulate at the lowest elevation possible, in accommodation spaces. The rate and magnitude of sedimentation controls the rate at which subsidence occurs, by contrast, in orogenic processes, mountain building creates a large load on the Earths crust, causing flexural depressions in adjacent lithospheric crust. These settings are not tectonically active, but still experience large-scale subsidence because of features of the crust. Intracontinental basins are large areal depressions that are inactive and not near any plate boundaries. Tectonic subsidence can occur in these environments as the crust pulls apart, successful rifting creates a spreading center like a mid-ocean ridge, which moves progressively further from coastlines as oceanic lithosphere is produced. Due to this phase of rifting, the crust in a passive margin is thinner than adjacent crust. Accumulation of non-marine sediment forms alluvial fans in the accommodation space, as rifting proceeds, listric fault systems form and further subsidence occurs, resulting in the creation of an ocean basin. After the cessation of rifting, cooling causes the crust to further subside, aulacogens occur at failed rifts, where continental crust does not completely split. Similar to the heating that occurs during the formation of passive margins. Once tensional forces cease, subsidence continues due to cooling, tectonic subsidence can occur in these settings as the plates collide against or under each other. Pull-apart basins have short-lived subsidence that forms from transtensional strike-slip faults, moderate strike-slip faults create extensional releasing bends and opposing walls pull apart from each other. Normal faults occur, inducing small scale subsidence in the area, cooling occurs after the fault fails to propagate further following the crustal thinning via normal faulting
23.
Crustal recycling
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Crustal recycling is a tectonic process by which surface material from the lithosphere is recycled into the mantle by subduction erosion or delamination. The subducting slabs carry volatile compounds and water into the mantle, identification of this crustal signature in mantle-derived rocks is proof of crustal recycling. Between 1906 and 1936 seismological data were used by R. D. Oldham, A. Mohorovičić, lehmann to show that the earth consisted of a solid crust and mantle, a fluid outer core and a solid innermost core. Whole-mantle convection proponents hold that the observed density differences do not restrict convective motion. If slabs are stalled out at the 660-km boundary, as the layered-mantle hypothesis suggests, they cannot be incorporated into hot spot plumes, if slabs end up in a slab graveyard at the core-mantle boundary, they cannot be involved in flat slab subduction geometry. Mantle dynamics is likely a mix of the two hypotheses, resulting in a partially layered mantle convection system. Seismology in particular is heavily relied upon for information about the deep mantle near the core-mantle boundary, showing a seismic tomography image that may be cold, folded slab material at the core-mantle boundary. However, the phase transitions may still play a role in the behavior of slabs at depth, schellart et al. showed that the 660-km phase transition may serve to deflect downgoing slabs. The shape of the zone was also key in whether the geometry of the slab could overcome the phase transition boundary. Additional work completed by Spasojevic et al. showed that local minima in the geoid could be accounted for by the processes that occur in and around slab graveyards, as indicated in their models. After a rock has moved to the surface of the earth from beneath the crust, one group of researchers was able to estimate that between 5 and 10% of the upper mantle is composed of recycled crustal material. The work done on carbonatites by Walter et al. and others further develops the magmas at depth as being derived from dewatering slab material
24.
Rare-earth mineral
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A rare earth mineral is a mineral that contains one or more rare earth elements as major metal constituents. Rare earth minerals are found in association with alkaline to peralkaline igneous complexes, in pegmatites associated with alkaline magmas. Perovskite mineral phases are common hosts to rare earth elements within the alkaline complexes, mantle-derived carbonate melts are also carriers of the rare earths. Hydrothermal deposits associated with alkaline magmatism contain a variety of rare earth minerals, Rare Earth Minerals, Chemistry, Origin and Ore Deposits, The Mineralogy Society Series #7,372 pp. ISBN 978-0-412-61030-1 China New Policy Affect Rare Earth Price
25.
Rare-earth element
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Scandium and yttrium are considered rare earth elements because they tend to occur in the same ore deposits as the lanthanides and exhibit similar chemical properties. They are not especially rare, but they tend to occur together in nature and are difficult to separate from one another, however, because of their geochemical properties, rare earth elements are typically dispersed and not often found concentrated as rare earth minerals in economically exploitable ore deposits. The first such mineral discovered was gadolinite, a composed of cerium, yttrium, iron, silicon. This mineral was extracted from a mine in the village of Ytterby in Sweden, a table listing the seventeen rare earth elements, their atomic number and symbol, the etymology of their names, and their main usages is provided here. The distinction between the groups is more to do with atomic volume and geological behavior, Rare earth elements became known to the world with the discovery of the black mineral Ytterbite by Lieutenant Carl Axel Arrhenius in 1787, at a quarry in the village of Ytterby, Sweden. Arrheniuss ytterbite reached Johan Gadolin, a Royal Academy of Turku professor, anders Gustav Ekeberg isolated beryllium from the gadolinite but failed to recognize other elements that the ore contained. After this discovery in 1794 a mineral from Bastnäs near Riddarhyttan, Sweden, in 1803 they obtained a white oxide and called it ceria. Martin Heinrich Klaproth independently discovered the same oxide and called it ochroia, in 1839 Carl Gustav Mosander, an assistant of Berzelius, separated ceria by heating the nitrate and dissolving the product in nitric acid. He called the oxide of the soluble salt lanthana and it took him three more years to separate the lanthana further into didymia and pure lanthana. Didymia, although not further separable by Mosanders techniques, was a mixture of oxides, in 1842 Mosander also separated the yttria into three oxides, pure yttria, terbia and erbia. The earth giving pink salts he called terbium, the one that yielded yellow peroxide he called erbium, so in 1842 the number of known rare earth elements had reached six, yttrium, cerium, lanthanum, didymium, erbium and terbium. This confusion led to false claims of new elements, such as the mosandrium of J. Lawrence Smith. There were no further discoveries for 30 years, and the element didymium was listed in the table of elements with a molecular mass of 138. In 1879 Delafontaine used the new process of optical-flame spectroscopy. Also in 1879, the new element samarium was isolated by Paul Émile Lecoq de Boisbaudran from the mineral samarskite, the samaria earth was further separated by Lecoq de Boisbaudran in 1886 and a similar result was obtained by Jean Charles Galissard de Marignac by direct isolation from samarskite. They named the element gadolinium after Johan Gadolin, and its oxide was named gadolinia, the fractional crystallization of the oxides then yielded europium in 1901. In 1839 the third source for rare earths became available and this is a mineral similar to gadolinite, uranotantalum. This mineral from Miass in the southern Ural Mountains was documented by Gustave Rose, the exact number of rare earth elements that existed was highly unclear, and a maximum number of 25 was estimated
26.
Manufacturing
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Manufacturing is the value added to production of merchandise for use or sale using labour and machines, tools, chemical and biological processing, or formulation. Manufacturing engineering or manufacturing process are the steps through which raw materials are transformed into a final product, the manufacturing process begins with the product design, and materials specification from which the product is made. These materials are modified through manufacturing processes to become the required part. Manufacturing takes turns under all types of economic systems, in a free market economy, manufacturing is usually directed toward the mass production of products for sale to consumers at a profit. In a collectivist economy, manufacturing is more directed by the state to supply a centrally planned economy. In mixed market economies, manufacturing occurs under some degree of government regulation, modern manufacturing includes all intermediate processes required the production and integration of a products components. Some industries, such as semiconductor and steel manufacturers use the term fabrication instead, the manufacturing sector is closely connected with engineering and industrial design. Examples of major manufacturers in North America include General Motors Corporation, General Electric, Procter & Gamble, General Dynamics, Boeing, Pfizer, examples in Europe include Volkswagen Group, Siemens, and Michelin. Examples in Asia include Sony, Huawei, Lenovo, Toyota, Samsung, in its earliest form, manufacturing was usually carried out by a single skilled artisan with assistants. In much of the world, the guild system protected the privileges. Before the Industrial Revolution, most manufacturing occurred in rural areas, entrepreneurs organized a number of manufacturing households into a single enterprise through the putting-out system. Toll manufacturing is an arrangement whereby a first firm with specialized equipment processes raw materials or semi-finished goods for a second firm, manufacturing provides important material support for national infrastructure and for national defense. On the other hand, most manufacturing may involve significant social and environmental costs, the clean-up costs of hazardous waste, for example, may outweigh the benefits of a product that creates it. Hazardous materials may expose workers to health risks and these costs are now well known and there is effort to address them by improving efficiency, reducing waste, using industrial symbiosis, and eliminating harmful chemicals. The negative costs of manufacturing can also be addressed legally, developed countries regulate manufacturing activity with labor laws and environmental laws. Across the globe, manufacturers can be subject to regulations and pollution taxes to offset the costs of manufacturing activities. Labor unions and craft guilds have played a role in the negotiation of worker rights. Environment laws and labor protections that are available in developed nations may not be available in the third world, tort law and product liability impose additional costs on manufacturing
27.
Oil depletion
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Oil depletion is the decline in oil production of a well, oil field, or geographic area. The Hubbert peak theory makes predictions of production based on prior discovery rates. Hubbert curves predict that the curves of non-renewing resources approximate a bell curve. Thus, according to theory, when the peak of production is passed. The United States Energy Information Administration predicted in 2006 that world consumption of oil will increase to 98.3 million barrels per day in 2015 and 118 million barrels per day in 2030. With 2009 world oil consumption at 84.4 mbd, reaching the projected 2015 level of consumption would represent an annual increase between 2009 and 2015 of 2. 7% per year. The Worlds natural oil supply is fixed because petroleum is naturally formed far too slowly to be replaced at the rate at which it is being extracted. Over many millions of years, plankton, bacteria, and other plant, when capped by impermeable rocks such as shale, salt, or igneous intrusions, they formed the petroleum reservoirs which are exploited today. For the short and medium-term, oil production occurs in a predictable manner based on geological circumstances, governmental policies. The shape of the curve varies depending upon whether one considers a well. In the longer term, technological developments have defied some of the predictions, an individual oil well usually produces at its maximum rate at the start of its life, the production rate eventually declines to a point at which it no longer produces profitable amounts. The shape of the curve depends on the oil reservoir. Wells in water-drive and gas-cap drive reservoirs often produce at a constant rate until the encroaching water or expanding gas cap reaches the well. Wells in gas solution drive and oil expansion drive reservoirs have exponential or hyperbolic declines, rapid declines at first, then leveling off. The shape of production curve of an oil well can also be affected by a number of nongeologic factors and this decreases the rate of decline, but will not change the wells total production significantly. Hydraulic fracturing or acidizing may be used to cause a spike in production. The field may undergo a secondary or tertiary recovery project, discussed in the next section, individual oil wells are typically within multi-well oil fields. As with individual wells, the curves for oil fields vary depending on geology
28.
Renewable energy
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Renewable energy is energy that is collected from renewable resources, which are naturally replenished on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat. Renewable energy often provides energy in four important areas, electricity generation, air and water heating/cooling, transportation, based on REN21s 2016 report, renewables contributed 19. 2% to humans global energy consumption and 23. 7% to their generation of electricity in 2014 and 2015, respectively. This energy consumption is divided as 8. 9% coming from biomass,4. 2% as heat energy,3. 9% hydro electricity and 2. 2% is electricity from wind, solar, geothermal. Worldwide investments in renewable technologies amounted to more than US$286 billion in 2015, with countries like China, globally, there are an estimated 7.7 million jobs associated with the renewable energy industries, with solar photovoltaics being the largest renewable employer. As of 2015 worldwide, more than half of all new electricity capacity installed was renewable, Renewable energy resources exist over wide geographical areas, in contrast to other energy sources, which are concentrated in a limited number of countries. Rapid deployment of energy and energy efficiency is resulting in significant energy security, climate change mitigation. In international public opinion there is strong support for promoting renewable sources such as solar power. At the national level, at least 30 nations around the already have renewable energy contributing more than 20 percent of energy supply. National renewable energy markets are projected to continue to grow strongly in the coming decade, for example, in Denmark the government decided to switch the total energy supply to 100% renewable energy by 2050. While many renewable energy projects are large-scale, renewable technologies are also suited to rural and remote areas and developing countries, United Nations Secretary-General Ban Ki-moon has said that renewable energy has the ability to lift the poorest nations to new levels of prosperity. Renewable energy systems are becoming more efficient and cheaper. Their share of energy consumption is increasing. Growth in consumption of coal and oil could end by 2020 due to increased uptake of renewables, in its various forms, it derives directly from the sun, or from heat generated deep within the earth. Included in the definition is electricity and heat generated from solar, wind, ocean, hydropower, biomass, geothermal resources, rapid deployment of renewable energy and energy efficiency, and technological diversification of energy sources, would result in significant energy security and economic benefits. New government spending, regulation and policies helped the industry weather the financial crisis better than many other sectors. As of 2011, small solar PV systems provide electricity to a few million households, United Nations Secretary-General Ban Ki-moon has said that renewable energy has the ability to lift the poorest nations to new levels of prosperity. At the national level, at least 30 nations around the already have renewable energy contributing more than 20% of energy supply. Some countries have much higher long-term policy targets of up to 100% renewables, outside Europe, a diverse group of 20 or more other countries target renewable energy shares in the 2020–2030 time frame that range from 10% to 50%
29.
Internal combustion engine
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An internal combustion engine is a heat engine where the combustion of a fuel occurs with an oxidizer in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal combustion engine the expansion of the high-temperature and high-pressure gases produced by combustion applies direct force to some component of the engine, the force is applied typically to pistons, turbine blades, rotor or a nozzle. This force moves the component over a distance, transforming chemical energy into mechanical energy. The first commercially successful internal combustion engine was created by Étienne Lenoir around 1859, firearms are also a form of internal combustion engine. Working fluids can be air, hot water, pressurized water or even liquid sodium, ICEs are usually powered by energy-dense fuels such as gasoline or diesel, liquids derived from fossil fuels. While there are many applications, most ICEs are used in mobile applications and are the dominant power supply for vehicles such as cars, aircraft. Typically an ICE is fed with fossil fuels like natural gas or petroleum products such as gasoline, there is a growing usage of renewable fuels like biodiesel for compression ignition engines and bioethanol or methanol for spark ignition engines. Hydrogen is sometimes used, and can be made from fossil fuels or renewable energy. Various scientists and engineers contributed to the development of internal combustion engines, in 1791, John Barber developed a turbine. In 1794 Thomas Mead patented a gas engine, also in 1794 Robert Street patented an internal combustion engine, which was also the first to use liquid fuel, and built an engine around that time. In 1798, John Stevens built the first American internal combustion engine, in 1807, Swiss engineer François Isaac de Rivaz built an internal combustion engine ignited by electric spark. In 1823, Samuel Brown patented the first internal combustion engine to be applied industrially, in 1860, Belgian Jean Joseph Etienne Lenoir produced a gas-fired internal combustion engine. In 1864, Nikolaus Otto patented the first atmospheric gas engine, in 1872, American George Brayton invented the first commercial liquid-fuelled internal combustion engine. In 1876, Nikolaus Otto, working with Gottlieb Daimler and Wilhelm Maybach, patented the compressed charge, in 1879, Karl Benz patented a reliable two-stroke gas engine. In 1892, Rudolf Diesel developed the first compressed charge, compression ignition engine, in 1926, Robert Goddard launched the first liquid-fueled rocket. In 1939, the Heinkel He 178 became the worlds first jet aircraft, at one time, the word engine meant any piece of machinery — a sense that persists in expressions such as siege engine. A motor is any machine that produces mechanical power, traditionally, electric motors are not referred to as Engines, however, combustion engines are often referred to as motors. In boating an internal combustion engine that is installed in the hull is referred to as an engine, reciprocating piston engines are by far the most common power source for land and water vehicles, including automobiles, motorcycles, ships and to a lesser extent, locomotives
30.
Infrastructure
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Infrastructure refers to the fundamental facilities and systems serving a country, city, or area, including the services and facilities necessary for its economy to function. The word was imported from French, where it means subgrade, the word is a combination of the Latin prefix infra, meaning below, and structure. The military use of the term achieved currency in the United States after the formation of NATO in the 1940s and this crisis discussion contributed to an increase in infrastructure asset management and maintenance planning in the US. Public-policy discussions have been hampered by lack of a definition for infrastructure. A1987 US National Research Council panel adopted the public works infrastructure. The OECD also classifies communications as a part of infrastructure, the American Society of Civil Engineers has not defined the term, though issuing a US Infrastructure Report Card every 2-4 years. Hard infrastructure refers to the physical networks necessary for the functioning of an industrial nation. The term critical infrastructure distinguishes those infrastructure elements that, if damaged or destroyed. Similarly, a booking system might be critical infrastructure for an airline. These elements of infrastructure are the focus of efforts in the aftermath of natural disasters. The term infrastructure may be confused with the following overlapping or related concepts, service connections to municipal service and public utility networks would also be considered land improvements, not infrastructure. The term public works includes government-owned and operated infrastructure as well as buildings, such as schools. Public works generally refers to physical assets needed to deliver public services, public services include both infrastructure and services generally provided by government. Infrastructure may be owned and managed by governments or by private companies, generally, most roads, major ports and airports, water distribution systems and sewage networks are publicly owned, whereas most energy and telecommunications networks are privately owned. Publicly owned infrastructure may be paid for taxes, tolls, or metered user fees. Major investment projects are financed by the issuance of long-term bonds. Government owned and operated infrastructure may be developed and operated in the sector or in public-private partnerships. As of 2008 in the United States for example, public spending on infrastructure has varied between 2. 3% and 3. 6% of GDP since 1950, many financial institutions invest in infrastructure
31.
Transport
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Transport or transportation is the movement of people, animals and goods from one location to another. Modes of transport include air, rail, road, water, cable, pipeline, the field can be divided into infrastructure, vehicles and operations. Transport is important because it enables trade between people, which is essential for the development of civilizations, terminals may be used both for interchange of passengers and cargo and for maintenance. Vehicles traveling on these networks may include automobiles, bicycles, buses, trains, trucks, people, helicopters, operations deal with the way the vehicles are operated, and the procedures set for this purpose including financing, legalities and policies. In the transport industry, operations and ownership of infrastructure can be public or private, depending on the country. Passenger transport may be public, where operators provide scheduled services, freight transport has become focused on containerization, although bulk transport is used for large volumes of durable items. Transport plays an important part in growth and globalization, but most types cause air pollution. While it is subsidized by governments, good planning of transport is essential to make traffic flow. A mode of transport is a solution that makes use of a type of vehicle, infrastructure. The transport of a person or of cargo may involve one mode or several of the modes, each mode has its own advantages and disadvantages, and will be chosen for a trip on the basis of cost, capability, and route. Human powered transport, a form of transportation, is the transport of people and/or goods using human muscle-power. Modern technology has allowed machines to enhance human power, human-powered vehicles have also been developed for difficult environments, such as snow and water, by watercraft rowing and skiing, even the air can be entered with human-powered aircraft. Animal-powered transport is the use of working animals for the movement of people, humans may ride some of the animals directly, use them as pack animals for carrying goods, or harness them, alone or in teams, to pull sleds or wheeled vehicles. A fixed-wing aircraft, commonly called airplane, is a craft where movement of the air in relation to the wings is used to generate lift. The term is used to distinguish this from rotary-wing aircraft, where the movement of the lift surfaces relative to the air generates lift, a gyroplane is both fixed-wing and rotary-wing. Fixed-wing aircraft range from small trainers and recreational aircraft to large airliners, two things necessary for aircraft are air flow over the wings for lift and an area for landing. The majority of aircraft also need an airport with the infrastructure to receive maintenance, restocking, refueling and for the loading and unloading of crew, cargo and passengers. While the vast majority of land and take off on land, some are capable of take off and landing on ice, snow
32.
Global warming
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Global warming and climate change are terms for the observed century-scale rise in the average temperature of the Earths climate system and its related effects. Multiple lines of evidence show that the climate system is warming. The largest human influence has been emission of gases such as carbon dioxide, methane. These findings have been recognized by the science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing. Future climate change and associated impacts will differ from region to region around the globe, anticipated effects include warming global temperature, rising sea levels, changing precipitation, and expansion of deserts in the subtropics. Warming is expected to be greater over land than over the oceans and greatest in the Arctic, with the retreat of glaciers, permafrost. Effects significant to humans include the threat to security from decreasing crop yields. Possible societal responses to global warming include mitigation by emissions reduction, adaptation to its effects, building systems resilient to its effects, most countries are parties to the United Nations Framework Convention on Climate Change, whose ultimate objective is to prevent dangerous anthropogenic climate change. Public reactions to global warming and concern about its effects are also increasing, a global 2015 Pew Research Center report showed a median of 54% consider it a very serious problem. There are significant regional differences, with Americans and Chinese among the least concerned, the global average surface temperature shows a warming of 0.85 °C in the period 1880 to 2012, based on multiple independently produced datasets. Earths average surface temperature rose by 0. 74±0.18 °C over the period 1906–2005, the rate of warming almost doubled for the last half of that period. The rest has melted ice and warmed the continents and atmosphere, the average temperature of the lower troposphere has increased between 0.12 and 0.135 °C per decade since 1979, according to satellite temperature measurements. The warming that is evident in the temperature record is consistent with a wide range of observations. The probability that these changes could have occurred by chance is virtually zero, temperature changes vary over the globe. Since 1979, land temperatures have increased about twice as fast as ocean temperatures, ocean temperatures increase more slowly than land temperatures because of the larger effective heat capacity of the oceans and because the ocean loses more heat by evaporation. Since the beginning of industrialisation the temperature difference between the hemispheres has increased due to melting of sea ice and snow in the North. Average arctic temperatures have been increasing at almost twice the rate of the rest of the world in the past 100 years, the thermal inertia of the oceans and slow responses of other indirect effects mean that climate can take centuries or longer to adjust to changes in forcing. Some of this warming will be driven by past natural forcings which are still seeking equilibrium in the climate system
33.
Climate change
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Climate change is a change in the statistical distribution of weather patterns when that change lasts for an extended period of time. Climate change may refer to a change in weather conditions. Climate change is caused by such as biotic processes, variations in solar radiation received by Earth, plate tectonics. Certain human activities have also identified as significant causes of recent climate change. Scientists actively work to understand past and future climate by using observations, more recent data are provided by the instrumental record. The most general definition of change is a change in the statistical properties of the climate system when considered over long periods of time. Accordingly, fluctuations over periods shorter than a few decades, such as El Niño, the term climate change is often used to refer specifically to anthropogenic climate change. Anthropogenic climate change is caused by activity, as opposed to changes in climate that may have resulted as part of Earths natural processes. In this sense, especially in the context of environmental policy, within scientific journals, global warming refers to surface temperature increases while climate change includes global warming and everything else that increasing greenhouse gas levels affect. A related term is climatic change, in 1966, the World Meteorological Organization proposed the term climatic change to encompass all forms of climatic variability on time-scales longer than 10 years, regardless of cause. Change was a given and climatic was used as an adjective to describe this kind of change, when it was realized that human activities had a potential to drastically alter the climate, the term climate change replaced climatic change as the dominant term to reflect an anthropogenic cause. Climate change was incorporated in the title of the Intergovernmental Panel on Climate Change, Climate change, used as a noun, became an issue rather than the technical description of changing weather. On the broadest scale, the rate at which energy is received from the Sun and this energy is distributed around the globe by winds, ocean currents, and other mechanisms to affect the climates of different regions. Factors that can shape climate are called climate forcings or forcing mechanisms, there are a variety of climate change feedbacks that can either amplify or diminish the initial forcing. Some parts of the system, such as the oceans and ice caps, respond more slowly in reaction to climate forcings. There are also key factors which when exceeded can produce rapid change. Forcing mechanisms can be internal or external. Internal forcing mechanisms are natural processes within the system itself
34.
Open-pit mining
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Open-pit, open-cast or open cut mining is a surface mining technique of extracting rock or minerals from the earth by their removal from an open pit or borrow. This form of mining differs from extractive methods that require tunneling into the earth, for minerals that occur deep below the surface—where the overburden is thick or the mineral occurs as veins in hard rock—underground mining methods are used to extract the valued material. Open-pit mines that produce building materials and dimension stone are commonly referred to as quarries, open-pit mines are typically enlarged until either the mineral resource is exhausted, or an increasing ratio of overburden to ore makes further mining uneconomic. When this occurs, the mines are sometimes converted to landfills for disposal of solid wastes. Open-cast mines are dug on benches, which describe vertical levels of the hole and these benches are usually on four to sixty meter intervals, depending on the size of the machinery that is being used. Many quarries do not use benches, as they are usually shallow, most walls of the pit are generally blast mined on an angle less than vertical, to prevent and minimize damage and danger from rock falls. This depends on how weathered the rocks are, and the type of rock, the inclined section of the wall is known as the batter, and the flat part of the step is known as the bench or berm. The steps in the walls help prevent rock falls continuing down the face of the wall. In some instances additional ground support is required and rock bolts, cable bolts, de-watering bores may be used to relieve water pressure by drilling horizontally into the wall, which is often enough to cause failures in the wall by itself. A haul road is situated at the side of the pit, forming a ramp up which trucks can drive, carrying ore. Waste rock is piled up at the surface, near the edge of the open pit and this is known as the waste dump. The waste dump is also tiered and stepped, to minimize degradation, ore which has been processed is known as tailings, and is generally a slurry. This is pumped to a dam or settling pond, where the water evaporates. This toxicity can harm the surrounding environment, after mining finishes, the mine area may undergo land rehabilitation. Waste dumps are contoured to flatten out, to further stabilise them. This is then covered with soil, and vegetation is planted to help consolidate the material. There are no long term studies on the success of these due to the relatively short time in which large scale open pit mining has existed. It may take hundreds to thousands of years for some waste dumps to become acid neutral, the dumps are usually fenced off to prevent livestock denuding them of vegetation
35.
McArthur River uranium mine
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The McArthur River Uranium Mine, in northern Saskatchewan, Canada, is the worlds largest high-grade uranium deposit. The McArthur River deposit was discovered in 1988, the property is located 620 air kilometres north of Saskatoon, Saskatchewan and 80 kilometres northeast of the Key Lake mill in the uranium rich Athabasca Basin. Mine construction began in 1997, with production commencing in 1999, the mine achieved full commercial production in November 2000. Production is regulated at 18.7 million pounds of yellowcake a year with the ore being processed through the Key Lake mill, between 2000 and 2013, the McArthur River/Key Lake operation has produced 250.6 million pounds U3O8. Note that this figure includes production from the former Key Lake mine as well as that derived from the McArthur River mine. The link also needs to be updated, in 2012, McArthur River was the worlds largest producing uranium mine, accounting for 13% of world mine production. As of December 31,2013, the mine has proven, during the most hazardous mining operations, remote controlled underground mining systems in this mine are used to reduce personnel exposure to rock particulates, radon gas, and other hazards. A video detailing the operations at the mine is provided by CAMECO, the McArthur River mine has been awarded the Canadian Institute of Mining, Metallurgy and Petroleums John T. Ryan Trophy for the best safety record for metal mines several times. This award is given to the mine with the best safety record for the previous year. National Trophy 200020102014 Regional Trophy - Prairies and Northwest Territories 2011 The mine is owned by Cameco and Areva Resources Canada, the mine is serviced by the McArthur River Airport to the northeast. It is also connected to the south by a restricted access haulage road, unconformity uranium deposits Uranium mining Uranium mining in Canada McArthur River
36.
Olympic Dam mine
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The Olympic Dam mine is a large poly-metallic underground mine located in South Australia,550 km NNW of Adelaide. It is the fourth largest copper deposit and the largest known deposit of uranium in the world. Approximately 70% of the revenue comes from copper, 25% from uranium. BHP Billiton has owned and operated the mine since 2005, the mine was previously owned by Western Mining Corporation. Since it opened in 1988, an underground mine, an integrated metallurgical processing plant. The adjacent Olympic Dam mining centre and the township of Roxby Downs service the mine. Daily flights to and from Adelaide are provided via the Olympic Dam Airport, BHP Billiton planned to expand the mine by establishing a new open cut pit and building extensive supporting infrastructure. In 2012 the expansion was postponed indefinitely pending investigation of a new, as of 2013, Olympic Dam is the second largest uranium-producing mine in the world, having produced 4,100 tonnes in the financial year ending June 2013. The only larger producer is the MacArthur River uranium mine in Canada, in 1979 a joint venture partnership was established between WMC Resources and BP Minerals with the intention of establishing the mine. Three years later, the Roxby Downs Act 1982 was signed, the first shaft was constructed that year, and named the Whenan Shaft after Ted Whenan, one of the exploration drillers who discovered the ore body. The new municipality of Roxby Downs was also created in 1982, as a service centre and community hub for the mine workers. In 1983, the mines first Environmental Impact Statement was approved, over a decade would pass before this production target was achieved. In 1987, an entrance to the mine was created. The mine was opened the following year, and the first shipments of copper cathodes. Roxby Downs township was opened, and the towns newspaper. In 1989, the Olympic Dam refinery produced its first gold, in 1993, Western Mining Corporation bought BPs 49% shareholding and assumed total control of the project. Several stages of expansion occurred around this time and production increased, in 1986, the mines target production had been set at 45,000 tonnes of copper per annum. In 1992, output reached 66,000 tonnes, then 84,000 in 1995, the mines first major expansion was announced in 1996 with the objective of producing 200,000 tonnes per annum once complete
37.
Uranium
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Uranium is a chemical element with symbol U and atomic number 92. It is a metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons, Uranium is weakly radioactive because all its isotopes are unstable. The most common isotopes in natural uranium are uranium-238 and uranium-235, Uranium has the highest atomic weight of the primordially occurring elements. Its density is about 70% higher than that of lead, and it occurs naturally in low concentrations of a few parts per million in soil, rock and water, and is commercially extracted from uranium-bearing minerals such as uraninite. In nature, uranium is found as uranium-238, uranium-235, Uranium decays slowly by emitting an alpha particle. The half-life of uranium-238 is about 4.47 billion years, many contemporary uses of uranium exploit its unique nuclear properties. Uranium-235 is the naturally occurring fissile isotope, which makes it widely used in nuclear power plants. However, because of the amounts found in nature, uranium needs to undergo enrichment so that enough uranium-235 is present. Uranium-238 is fissionable by fast neutrons, and is fertile, meaning it can be transmuted to fissile plutonium-239 in a nuclear reactor, another fissile isotope, uranium-233, can be produced from natural thorium and is also important in nuclear technology. In sufficient concentration, these maintain a sustained nuclear chain reaction. This generates the heat in nuclear reactors, and produces the fissile material for nuclear weapons. Depleted uranium is used in kinetic energy penetrators and armor plating, Uranium is used as a colorant in uranium glass, producing lemon yellow to green colors. Uranium glass fluoresces green in ultraviolet light and it was also used for tinting and shading in early photography. The 1789 discovery of uranium in the mineral pitchblende is credited to Martin Heinrich Klaproth, eugène-Melchior Péligot was the first person to isolate the metal and its radioactive properties were discovered in 1896 by Henri Becquerel. An ensuing arms race during the Cold War between the United States and the Soviet Union produced tens of thousands of weapons that used uranium metal. The security of those weapons and their fissile material following the breakup of the Soviet Union in 1991 is a concern for public health. When refined, uranium is a white, weakly radioactive metal
38.
Thorium
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Thorium is a chemical element with symbol Th and atomic number 90. A radioactive actinide metal, thorium is one of only two significantly radioactive elements that occur naturally in large quantities as a primordial element. It was discovered in 1829 by the Norwegian amateur mineralogist Morten Thrane Esmark and identified by the Swedish chemist Jöns Jacob Berzelius, who named it after Thor, a thorium atom has 90 protons and therefore 90 electrons, of which four are valence electrons. Thorium metal is silvery and tarnishes black when exposed to air, Thorium is weakly radioactive, all of its known isotopes are unstable. Thorium-232, which has 142 neutrons, is the most stable isotope of thorium and accounts for all natural thorium. Thorium is estimated to be three to four times more abundant than uranium in the Earths crust, and is chiefly refined from monazite sands as a by-product of extracting rare earth metals. Thorium was once used as the light source in gas mantles and as an alloying material. Thorium is still used as an alloying element in TIG welding electrodes. Thorium is predicted to be able to replace uranium as fuel in nuclear reactors. Thorium is a soft, paramagnetic, bright silvery radioactive actinide metal, in the periodic table, it is located to the right of the actinide actinium, to the left of the actinide protactinium, and below the lanthanide cerium. Pure thorium is very ductile and, as normal for metals, can be cold-rolled, swaged, at room temperature, thorium metal has a face-centred cubic crystal structure, additionally, it has two other forms at exotic conditions, one at high temperature and one at high pressure. The properties of thorium vary widely depending on the amount of impurities in the sample, the purest thorium specimens usually contain about a tenth of a percent of the dioxide. These values lie intermediate between those of its neighbours actinium and protactinium, showing the continuity of trends across the early actinides, thoriums melting point of 1750 °C is above both that of actinium and that of protactinium. After thorium, there is a new smooth trend downward in the points of the early actinides from thorium to plutonium where the number of f electrons increases from about 0. Thorium has a modulus of 54 GPa, comparable to those of tin. The hardness of thorium is similar to that of steel, so heated pure thorium can be rolled in sheets. Nevertheless, while thorium is nearly half as dense as uranium and plutonium, Thorium becomes superconductive below 1.4 K. Thorium can also form alloys with many other metals. With chromium and uranium, it forms eutectic mixtures, and thorium is completely miscible in both solid and liquid states with its lighter congener cerium, as such, 232Th still occurs naturally today, four-fifths of the thorium present at Earths formation has survived to the present
39.
Radionuclide
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A radionuclide is an atom that has excess nuclear energy, making it unstable. During those processes, the radionuclide is said to undergo radioactive decay, the unstable nucleus is more stable following the emission, but will sometimes undergo further decay. Radioactive decay is a process at the level of single atoms. However, for a collection of atoms of an element the decay rate. The range of the half-lives of radioactive atoms have no known limits, Radionuclides occur naturally and are artificially produced in nuclear reactors, cyclotrons, particle accelerators or radionuclide generators. There are about 730 radionuclides with half-lives longer than 60 minutes, with the longest half lives are the 32 primordial radionuclides that have survived from the creation of the Solar System. Over 60 further radionuclides are detectable in nature, either as daughters of these, more than 2400 radionuclides have half-lives less than 60 minutes. Most of those are produced artificially, and have very short half-lives. For comparison, there are about 254 stable nuclides, even the lightest element, hydrogen, has a well-known radionuclide, tritium. Elements heavier than lead, and the elements technetium and promethium, unplanned exposure to radionuclides generally has a harmful effect on living organisms including humans, although low levels of exposure occur naturally without harm. However, radionuclides with suitable properties are used in medicine for both diagnosis and treatment. An imaging tracer made with radionuclides is called a radioactive tracer, a pharmaceutical drug made with radionuclides is called a radiopharmaceutical. On Earth, naturally occurring radionuclides fall into three categories, primordial radionuclides, secondary radionuclides, and cosmogenic radionuclides, Radionuclides are produced in stellar nucleosynthesis and supernova explosions along with stable nuclides. Most decay quickly but can still be observed astronomically and can play a part in understanding astronomic processes, primordial radionuclides, such as uranium and thorium, exist in the present time because their half-lives are so long they have not yet completely decayed. It is possible decay may be observed in other nuclides adding to this list of primordial radionuclides, secondary radionuclides are radiogenic isotopes derived from the decay of primordial radionuclides. They have shorter half-lives than primordial radionuclides and they arise in the decay chain of the primordial isotopes thorium-232, uranium-238 and uranium-235. Examples include the natural isotopes of polonium and radium, cosmogenic isotopes, such as carbon-14, are present because they are continually being formed in the atmosphere due to cosmic rays. Many of these radionuclides exist only in trace amounts in nature, secondary radionuclides will occur in proportion to their half-lives, so short-lived ones will be very rare
40.
Fly ash
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Fly ash, also known as pulverised fuel ash in the United Kingdom, is one of the coal combustion products, composed of the fine particles that are driven out of the boiler with the flue gases. Ash that falls in the bottom of the boiler is called bottom ash, in modern coal-fired power plants, fly ash is generally captured by electrostatic precipitators or other particle filtration equipment before the flue gases reach the chimneys. Together with bottom ash removed from the bottom of the boiler, in the past, fly ash was generally released into the atmosphere, but air pollution control standards now require that it be captured prior to release by fitting pollution control equipment. In the US, fly ash is stored at coal power plants or placed in landfills. About 43% is recycled, often used as a pozzolan to produce hydraulic cement or hydraulic plaster, pozzolans ensure the setting of concrete and plaster and provide concrete with more protection from wet conditions and chemical attack. Coal Combustion Residuals are listed in the subtitle D, in that case the ash produced is often classified as hazardous waste. Fly ash material solidifies while suspended in the exhaust gases and is collected by electrostatic precipitators or filter bags. Since the particles solidify rapidly while suspended in the exhaust gases, fly ash particles are spherical in shape. The major consequence of the cooling is that few minerals have time to crystallize. Nevertheless, some refractory phases in the coal do not melt. In consequence, fly ash is a heterogeneous material, siO2, Al2O3, Fe2O3 and occasionally CaO are the main chemical components present in fly ashes. The mineralogy of fly ashes is very diverse, the main phases encountered are a glass phase, together with quartz, mullite and the iron oxides hematite, magnetite and/or maghemite. Other phases often identified are cristobalite, anhydrite, free lime, periclase, calcite, sylvite, halite, portlandite, rutile and anatase. The Ca-bearing minerals anorthite, gehlenite, akermanite and various calcium silicates, the mercury content can reach 1 ppm, but is generally included in the range 0.01 -1 ppm for bituminous coal. The concentrations of trace elements vary as well according to the kind of coal combusted to form it. In fact, in the case of coal, with the notable exception of boron. Two classes of fly ash are defined by ASTM C618, Class F fly ash, the chief difference between these classes is the amount of calcium, silica, alumina, and iron content in the ash. The chemical properties of the fly ash are largely influenced by the content of the coal burned
41.
Oak Ridge National Laboratory
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Oak Ridge National Laboratory is an American multiprogram science and technology national laboratory managed for the United States Department of Energy by UT-Battelle. ORNL is the largest science and energy national laboratory in the Department of Energy system by surface, ORNL is located in Oak Ridge, Tennessee, near Knoxville. ORNLs scientific programs focus on materials, neutron science, energy, high-performance computing, systems biology, ORNL partners with the state of Tennessee, universities and industries to solve challenges in energy, advanced materials, manufacturing, security and physics. ORNL hosts the Center for Nanophase Materials Sciences, the BioEnergy Science Center, Oak Ridge National Laboratory is managed by UT-Battelle, a limited liability partnership between the University of Tennessee and the Battelle Memorial Institute, formed in 2000 for that purpose. The annual budget is US$1.65 billion, 80% of which is from the Department of Energy, as of 2012 there are 4,400 staff working at ORNL,1,600 of whom are directly conducting research, and an additional 3,000 guest researchers annually. The total area of the reservation 150 square kilometres of which the lab takes up 18 square kilometres, the town of Oak Ridge was established by the Army Corps of Engineers as part of the Clinton Engineer Works in 1942 on isolated farm land as part of the Manhattan Project. During the war, advanced research for the government was managed at the site by the University of Chicago, in 1943, construction of the Clinton Laboratories was completed, later renamed to Oak Ridge National Laboratory. The site was chosen for the X-10 Graphite Reactor, used to show that plutonium can be extracted from enriched uranium, enrico Fermi and his colleagues developed the worlds second self-sustaining nuclear reactor after Fermis previous experiment, the Chicago Pile-1. The X-10 was the first reactor designed for continuous operation, in 1946 the first medical isotopes were produced in the X-10 reactor, by 1950 almost 20,000 samples had been shipped to various hospitals. As the demand for military science had fallen dramatically the future of the lab was uncertain, management of the lab was contracted by the US government to Monsanto, however, they withdrew in 1947. In 1950 the Oak Ridge School of Reactor Technology was established with two courses in operation and safety, almost 1000 students graduated. Another project was the worlds first light water reactor, with its principles of neutron moderation and fuel cooling by ordinary water it is the direct ancestor of most modern nuclear power stations. The US Military funded much of its development, for nuclear-powered submarines, the US Army contracted portable nuclear reactors in 1953 for heat and electricity generation in remote military bases. The reactors were designed at ORNL, produced by American Locomotive Company and used in Greenland, the United States Air Force also contributed funding to three reactors, the labs first computers, and its first particle accelerators. ORNL designed and tested an aircraft in 1954 as a proof-of-concept for a proposed USAF fleet of long-range bombers. The provision of radionuclides by X-10 for medicine grew steadily in the 1950s with more isotopes available, ORNL scientists lowered the immune systems of mice and performed the worlds first successful bone marrow transplant. In the early 1960s there was a push at ORNL to develop nuclear-powered desalination plants where deserts met the sea to provide water. The Health Physics Research Reactor built in 1962 was used for exposure experiments leading to more accurate dosage limits, dosimeters
42.
Actinide
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The actinide /ˈæktᵻnaɪd/ or actinoid /ˈæktᵻnɔɪd/ series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium through lawrencium. The actinide series derives its name from the first element in the series, the informal chemical symbol An is used in general discussions of actinide chemistry to refer to any actinide. All but one of the actinides are f-block elements, corresponding to the filling of the 5f electron shell, lawrencium, in comparison with the lanthanides, also mostly f-block elements, the actinides show much more variable valence. They all have very large atomic and ionic radii and exhibit a large range of physical properties. While actinium and the late actinides behave similarly to the lanthanides, all actinides are radioactive and release energy upon radioactive decay, naturally occurring uranium and thorium, and synthetically produced plutonium are the most abundant actinides on Earth. These are used in nuclear reactors and nuclear weapons, uranium and thorium also have diverse current or historical uses, and americium is used in the ionization chambers of most modern smoke detectors. Of the actinides, primordial thorium and uranium occur naturally in substantial quantities, the radioactive decay of uranium produces transient amounts of actinium and protactinium, and atoms of neptunium and plutonium are occasionally produced from transmutation reactions in uranium ores. The other actinides are purely synthetic elements, like the lanthanides, the actinides form a family of elements with similar properties. Within the actinides, there are two overlapping groups, transuranium elements, which follow uranium in the periodic table—and transplutonium elements, compared to the lanthanides, which are found in nature in appreciable quantities, most actinides are rare. The most abundant, or easily synthesized actinides are uranium and thorium, the existence of transuranium elements was suggested by Enrico Fermi based on his experiments in 1934. However, even though four actinides were known by that time, synthesis of transuranics gradually undermined this point of view. By 1944 an observation that curium failed to exhibit oxidation states above 4 prompted Glenn Seaborg to formulate a so-called actinide hypothesis, at present, there are two major methods of producing isotopes of transplutonium elements, irradiation of the lighter elements with either neutrons or accelerated charged particles. The advantage of the method is that elements heavier than plutonium, as well as neutron-deficient isotopes, can be obtained. In 1962–1966, there were attempts in the United States to produce transplutonium isotopes using a series of six underground nuclear explosions and this inobservation was attributed to spontaneous fission owing to the large speed of the products and to other decay channels, such as neutron emission and nuclear fission. Uranium and thorium were the first actinides discovered, uranium was identified in 1789 by the German chemist Martin Heinrich Klaproth in pitchblende ore. He named it after the planet Uranus, which had been discovered eight years earlier. Klaproth was able to precipitate a yellow compound by dissolving pitchblende in nitric acid and he then reduced the obtained yellow powder with charcoal, and extracted a black substance that he mistook for metal. Only 60 years later, the French scientist Eugène-Melchior Péligot identified it with uranium oxide and he also isolated the first sample of uranium metal by heating uranium tetrachloride with potassium
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Nuclear fuel
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Nuclear fuel is a substance that is used in nuclear power stations to produce heat to power turbines. Heat is created when nuclear fuel undergoes nuclear fission, most nuclear fuels contain heavy fissile elements that are capable of nuclear fission, such as uranium-235 or plutonium-239. When the unstable nuclei of atoms are hit by a slow-moving neutron, they split. These neutrons then go on to split more nuclei and this creates a self-sustaining chain reaction that is controlled in a nuclear reactor, or uncontrolled in a nuclear weapon. The processes involved in mining, refining, purifying, using, Nuclear fuel has the highest energy density of all practical fuel sources. Uranium dioxide is a black semiconducting solid and it can be made by reacting uranyl nitrate with a base to form a solid. It is heated to form U3O8 that can then be converted by heating in an argon / hydrogen mixture to form UO2, the UO2 is then mixed with an organic binder and pressed into pellets, these pellets are then fired at a much higher temperature to sinter the solid. The aim is to form a solid which has few pores. The thermal conductivity of uranium dioxide is low compared with that of zirconium metal. It is important to note that the corrosion of uranium dioxide in an environment is controlled by similar electrochemical processes to the galvanic corrosion of a metal surface. Mixed oxide, or MOX fuel, is a blend of plutonium, MOX fuel is an alternative to low enriched uranium fuel used in the light water reactors which predominate nuclear power generation. Some concern has been expressed that used MOX cores will introduce new disposal challenges, reprocessing of commercial nuclear fuel to make MOX was done in the Sellafield MOX Plant. As of 2015, MOX fuel is made in France, and to an extent in Russia, India. China plans to develop fast breeder reactors and reprocessing, reprocessing of spent commercial-reactor nuclear fuel has not been permitted in the United States due to nonproliferation considerations. It behaves like U-235 and its fission releases a similar amount of energy, the higher the burn-up, the more plutonium in the spent fuel, but the lower the fraction of fissile plutonium. Typically about one percent of the used fuel discharged from a reactor is plutonium, worldwide, some 70 tonnes of plutonium contained in used fuel is removed when refueling reactors each year. Metal fuels have the advantage of a higher heat conductivity than oxide fuels. Metal fuels have a history of use, stretching from the Clementine reactor in 1946 to many test
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Nuclear power proposed as renewable energy
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Although nuclear power is considered a form of low-carbon power, its legal inclusion with renewable energy power sources has been a subject of debate and classification. Similarly, the National Renewable Energy Laboratory does not mention nuclear power in its energy basics definition, the monitoring and storage of radioactive waste products is also required upon the use of other renewable energy sources, such as geothermal energy. In its various forms, it directly from the sun. Included in the definition is electricity and heat generated from sunlight, wind, oceans, hydropower, biomass, geothermal resources, Renewable energy resources exist over wide geographical areas, in contrast to other energy sources, which are concentrated in a limited number of countries. It ran for a few hundred years, averaging 100 kW of thermal power during that time. Conventional, human manufactured, nuclear power stations largely use uranium, a common metal found in seawater. Uranium-235 burnt in conventional reactors, without fuel recycling, is a non-renewable resource, as too will the Sun, and be exhausted. Fertile materials are also nonrenewable, but their supply on Earth is extremely large, in a closed nuclear fuel cycle utilizing breeder reactors, nuclear fuel could therefore be considered renewable. In 2016 the global effort in the field of research was the subject of an issue in the journal of Industrial & Engineering Chemistry Research. Presently, as of 2014, only 2 breeder reactors are producing industrial quantities of electricity, the retired French Phénix reactor also demonstrated a greater than one breeding ratio and operated for ~30 years, producing power when Our Common Future was published in 1987. The worlds measured resources of uranium-235 in 2014 was estimated to be enough to last over 135 years at 2014 consumption rates. Alternatively this is about 6,500 years with a nuclear reactor fleet of 3,000 GW. Thorium, an often overlooked alternative to fertile U-238 in breeder reactors, is several times more abundant in the earth crust than natural uranium-238, inclusion under the renewable energy classification as well as the low-carbon classification could render nuclear power projects eligible for development aid under more jurisdictions. Thus a key issue regarding this classification of nuclear power is inclusion in Renewable portfolio standard, a bill proposed in the South Carolina Legislature in 2007-2008 aimed to classify nuclear power as renewable energy. In 2009 the Utah state passed the bill ECONOMIC DEVELOPMENT INCENTIVES FOR ALTERNATIVE ENERGY PROJECTS including incentives for energy projects. It includes a reference to nuclear power, Renewable energy means the energy generation as defined in Subsection 10-19-102. The bill passed the house with 72 yeas,0 nays, and 3 absent, passed the senate with 24 yeas,1 nay, in 2010 the Arizona Legislature included nuclear power in a proposed bill for electric utility renewable energy standards. The bill defined renewable energy as energy that is renewable and non-carbon emitting and it listed solar, wind, geothermal, biomass, hydroelectric, agricultural waste, landfill gas and nuclear sources
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Peak uranium
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Peak uranium is the point in time that the maximum global uranium production rate is reached. After that peak, according to Hubbert peak theory, the rate of production enters a terminal decline, while uranium is used in nuclear weapons, its primary use is for energy generation via nuclear fission of the uranium-235 isotope in a nuclear power reactor. Uranium-235 is a finite non-renewable resource, however, the current reserves of uranium have the potential to provide power for humanity for billions of years, until the death of our sun, so nuclear power can be considered sustainable energy. M. King Hubbert created his theory in 1956 for a variety of finite resources such as coal, oil. He and others since have argued that if the fuel cycle can be closed. Breeding and nuclear reprocessing potentially would allow the extraction of the largest amount of energy from natural uranium, however, only a small amount of uranium is currently being bred into plutonium and only a small amount of fissile uranium and plutonium is being recovered from nuclear waste worldwide. Furthermore, the technologies to eliminate the waste in the nuclear fuel cycle do not yet exist. Since the nuclear fuel cycle is not closed, Hubbert peak theory may be applicable. Pessimistic predictions of future high-grade uranium production operate on the thesis that either the peak has occurred in the 1980s or that a second peak may occur sometime around 2035. At the start of 2015, identified uranium reserves recoverable at US$130/kg were 5.7 million tons, at the rate of consumption in 2014, these reserves are sufficient for 135 years of supply. The identified reserves as of 2015 recoverable at US$260/kg are 7.64 million tons.3 million tons, theoretically 4.5 billion tons of uranium are available from sea water at about 10 times the current price of uranium. Currently no practical methods for high volume extraction exist, Thorium can be used when supplies of uranium are depleted. If these predictions became reality it has the potential to increase the supply of nuclear fuel significantly, optimistic predictions claim that the supply is far more than demand and do not predict peak uranium. Uranium-235, the isotope of uranium used in nuclear reactors. It is the naturally occurring isotope capable of directly generating nuclear power. It is believed that its availability follows M. King Hubberts peak theory, if these and other more costly technologies such as seawater extraction are used, any possible peak would occur in the very distant future. After a Hubberts peak, the rate of supply of a no longer fulfills the previous demand rate. As a result of the law of supply and demand, at point the market shifts from a buyers market to a sellers market
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United Nations
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The United Nations is an intergovernmental organization to promote international co-operation. A replacement for the ineffective League of Nations, the organization was established on 24 October 1945 after World War II in order to prevent another such conflict, at its founding, the UN had 51 member states, there are now 193. The headquarters of the UN is in Manhattan, New York City, further main offices are situated in Geneva, Nairobi, and Vienna. The organization is financed by assessed and voluntary contributions from its member states, the UNs mission to preserve world peace was complicated in its early decades by the Cold War between the US and Soviet Union and their respective allies. The organization participated in actions in Korea and the Congo. After the end of the Cold War, the UN took on major military, the UN has six principal organs, the General Assembly, the Security Council, the Economic and Social Council, the Secretariat, the International Court of Justice, and the UN Trusteeship Council. UN System agencies include the World Bank Group, the World Health Organization, the World Food Programme, UNESCO, the UNs most prominent officer is the Secretary-General, an office held by Portuguese António Guterres since 2017. Non-governmental organizations may be granted consultative status with ECOSOC and other agencies to participate in the UNs work, the organization won the Nobel Peace Prize in 2001, and a number of its officers and agencies have also been awarded the prize. Other evaluations of the UNs effectiveness have been mixed, some commentators believe the organization to be an important force for peace and human development, while others have called the organization ineffective, corrupt, or biased. Following the catastrophic loss of life in the First World War, the earliest concrete plan for a new world organization began under the aegis of the US State Department in 1939. It incorporated Soviet suggestions, but left no role for France, four Policemen was coined to refer to four major Allied countries, United States, United Kingdom, Soviet Union, and China, which emerged in the Declaration by United Nations. Roosevelt first coined the term United Nations to describe the Allied countries, the term United Nations was first officially used when 26 governments signed this Declaration. One major change from the Atlantic Charter was the addition of a provision for religious freedom, by 1 March 1945,21 additional states had signed. Each Government pledges itself to cooperate with the Governments signatory hereto, the foregoing declaration may be adhered to by other nations which are, or which may be, rendering material assistance and contributions in the struggle for victory over Hitlerism. During the war, the United Nations became the term for the Allies. To join, countries had to sign the Declaration and declare war on the Axis, at the later meetings, Lord Halifax deputized for Mr. Eden, Wellington Koo for T. V. Soong, and Mr Gromyko for Mr. Molotov. The first meetings of the General Assembly, with 51 nations represented, the General Assembly selected New York City as the site for the headquarters of the UN, and the facility was completed in 1952. Its site—like UN headquarters buildings in Geneva, Vienna, and Nairobi—is designated as international territory, the Norwegian Foreign Minister, Trygve Lie, was elected as the first UN Secretary-General
