EARTHQUAKES |
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An earthquake is a sudden and sometimes catastrophic movement of a part of the Earth's surface. Earthquakes result from the dynamic release of elastic strain energy that radiates seismic waves. Earthquakes typically result from the movement of faults, planar zones of deformation within the Earth's upper crust. The word earthquake is also widely used to indicate the source region itself. The Earth's lithosphere is a patch work of plates in slow but constant motion (see plate tectonics). Earthquakes occur where the stress resulting from the differential motion of these plates exceeds the strength of the crust. The highest stress (and possible weakest zones) are most often found at the boundaries of the tectonic plates and hence these locations are where the majority of earthquakes occur. Events located at plate boundaries are called interplate earthquakes; the less frequent events that occur in the interior of the lithospheric plates are called intraplate earthquakes (see, for example, New Madrid Seismic Zone). Earthquakes related to plate tectonics are called tectonic earthquakes. Most earthquakes are tectonic, but they also occur in volcanic regions and as the result of a number of anthropogenic sources, such as reservoir induced seismicity, mining and the removal or injection of fluids into the crust. Seismic waves including some strong enough to be felt by humans can also be caused by explosions (chemical or nuclear), landslides, and collapse of old mine shafts, though these sources are not strictly earthquakes. These sources will also show a different seismogram than earthquakes
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METALLURGY |
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Metallurgy is a domain of materials science and of materials engineering that studies the physical and chemical behavior of metallic elements, their intermetallic compounds and their mixtures, which are called alloys.
Extractive metallurgy is the practice of separating metals from their ore, and refining them into a pure metal. In order to convert a metal oxide or sulfide to a metal, the metal oxide must be reduced either chemically or electrolytically.
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MINING (ORES, PROCESSING) |
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Mining is the extraction of valuable minerals or other geological materials from the earth, usually (but not always) from an ore body, vein, or (coal) seam. Materials recovered by mining include bauxite, coal, diamonds, iron, precious metals, lead, limestone, nickel, phosphate, rock salt, tin,uranium, and molybdenum. Any material that cannot be grown from agricultural processes must be mined. Mining in a wider sense can also include extraction of petroleum, natural gas, and even water.
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POLLUTION |
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Pollution is the release of environmental contaminants. Carbon monoxide, sulfur dioxide, chlorofluorocarbons (CFCs), and nitrogen oxides produced by industry and motor vehicles are common air pollutants. Sunlight converts nitrogen oxides and hydrocarbons to ozone or smog. Water pollutants may consist of a wide range of organic and inorganic chemicals such as heavy metals, petrochemicals, chloroform, and bacteria. Water pollution may also occur in the form of thermal pollution and dissolved oxygen depletion. Soil contamination is an important aspect of environmental pollution; this phenomenon occurs when chemicals are released by spill or underground storage tank leakage. Among the most significant soil contaminants are hydrocarbons, heavy metals, MTBE, herbicides, pesticides and chlorinated hydrocarbons. The U.S., Russia, China and Japan are the world leaders in air pollution emissions; however, Canada is the number two country on a per capita basis.
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POWER PLANTS |
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A fossil fuel power plant is an energy conversion center that combusts fossil fuels to produce electricity, designed on a large scale for continuous operation.
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PULMONARY MEDICINE |
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Pulmonary Medicine - In medicine, pulmonology (aka pneumology) is the specialty that deals with diseases of the lungs and the respiratory tract. It is called chest medicine and respiratory medicine in some countries and areas.
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TECHNOLOGY |
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Technology is a word with origins in the Greek "technologia" ("τεχνολογία") "techne", "τέχνη" ("craft") and "logia", "λογία" ("saying")." "Technology" is a broad term dealing with the use and knowledge of humanity's tools and crafts.
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