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Geologists study and analyze rocks and the features and processes of the earth’s interior and surface.
Ore that contains a fairly large amount of the desired mineral.
Rock formed when molten rock material (magma) wells up from the earth’s interior, cools, and solidifies into rock masses. Compare metamorphic rock, sedimentary rock.
Outer shell of the earth, composed of the crust and the rigid, outermost part of the mantle outside the asthenosphere; material found in earth’s plates.
Ore that contains a smaller amount of the desired mineral.
Molten rock below the earth’s surface.
Zone of the earth’s interior between its core and its crust.
Compare core, crust.
Rock produced when a preexisting rock is subjected to high temperatures (which may cause it to melt partially), high pressures, chemically active fluids, or a combination of these agents.
Any naturally occurring inorganic substance found in the earth’s crust as a crystalline solid.
Type of surface mining that uses explosives, massive shovels, and even larger machinery called draglines to remove the top of a mountain to expose seams of coal underneath a mountain.
Removing minerals such as gravel, sand, and metal ores by digging them out of the earth’s surface and leaving an open pit.
Part of a metal-yielding material that can be economically and legally extracted at a given time.
An ore typically contains two parts: the ore mineral, which contains the desired metal, and waste mineral material (gangue).
Layer of soil and rock overlying a mineral deposit. Surface mining removes this layer.
Theory of geophysical processes that explains the movements of lithospheric plates and the processes that occur at their boundaries.
Rock that forms from the accumulated products of erosion and in some cases from the compacted shells, skeletons, and other remains of dead organisms.
Process in which a desired metal is separated from the other elements in an ore mineral.
Unwanted rock and other waste materials produced when a material is removed from the earth’s surface or subsurface by mining, dredging, quarrying, and excavation.
Form of surface mining in which bulldozers, power shovels, or stripping wheels remove large chunks of the earth’s surface in strips.
Area in which oceanic lithosphere is carried downward (subducted) under the island arc or continent at a convergent plate boundary.
A trench ordinarily forms at the boundary between the two converging plates.
Extraction of a metal ore or fuel resource such as coal from a deep underground deposit.
Removing soil, subsoil, and other strata and then extracting a mineral deposit found fairly close to the earth’s surface.
Various-sized areas of the earth’s lithosphere that move slowly around with the mantle’s flowing asthenosphere.
Most earthquakes and volcanoes occur around the boundaries of these plates.
Area where the earth’s lithospheric plates move in opposite but parallel directions along a fracture (fault) in the lithosphere.
Series of large waves generated when part of the ocean floor suddenly rises or drops, usually because of an earthquake.
Vent or fissure in the earth’s surface through which magma, liquid lava, and gases are released into the environment.
Physical and chemical processes in which solid rock exposed at earth’s surface is changed to separate solid particles and dissolved material, which can then be moved to another place as sediment. See erosion.
Gooey, black, high-sulfur, heavy oil extracted from tar sand and then upgraded to synthetic fuel oil.
Solid, combustible mixture of organic compounds with 30[[endash]]98% carbon by weight, mixed with various amounts of water and small amounts of sulfur and nitrogen compounds. It forms in several stages as the remains of plants are subjected to heat and pressure over millions of years.
Conversion of solid coal to synthetic natural gas (SNG).
Conversion of solid coal to a liquid hydrocarbon fuel such as synthetic gasoline or methanol.
Gooey liquid consisting mostly of hydrocarbon compounds and small amounts of compounds containing oxygen, sulfur, and nitrogen.
Extracted from underground accumulations, it is sent to oil refineries, where it is converted to heating oil, diesel fuel, gasoline, tar, and other materials.
Solid, waxy mixture of hydrocarbons found in oil shale rock. Heating the rock to high temperatures causes the kerogen to vaporize. The vapor is condensed, purified, and then sent to a refinery to produce gasoline, heating oil, and other products.
liquefied natural gas (LNG)
Natural gas converted to liquid form by cooling to a very low temperature.
liquefied petroleum gas (LPG)
Mixture of liquefied propane (C3H8) and butane (C4H10) gas removed from natural gas and used as a fuel.
Underground deposits of gases consisting of 50[[endash]]90% by weight methane gas (CH4) and small amounts of heavier gaseous hydrocarbon compounds such as propane (C3H8) and butane (C4H10).
Total amount of useful energy available from an energy resource or energy system over its lifetime, minus the amount of energy used (the first energy law), automatically wasted (the second energy law), and unnecessarily wasted in finding, processing, concentrating, and transporting it to users.
Deposit of a mixture of clay, sand, water, and varying amounts of a tar-like heavy oil known as bitumen. Bitumen can be extracted from tar sand by heating. It is then purified and upgraded to synthetic crude oil.
Fine-grained rock containing various amounts of kerogen, a solid, waxy mixture of hydrocarbon compounds. Heating the rock to high temperatures converts the kerogen into a vapor that can be condensed to form a slow-flowing heavy oil called shale oil.
Chemicals obtained by refining (distilling) crude oil. They are used as raw materials in manufacturing most industrial chemicals, fertilizers, pesticides, plastics, synthetic fibers, paints, medicines, and many other products.
Slow-flowing, dark brown, heavy oil obtained when kerogen in oil shale is vaporized at high temperatures and then condensed. Shale oil can be refined to yield gasoline, heating oil, and other petroleum products.
Synthetic gaseous and liquid fuels produced from solid coal or sources other than natural gas or crude oil.
synthetic natural gas (SNG)
Gaseous fuel containing mostly methane produced from solid coal.
Rock and other waste materials removed as impurities when waste mineral material is separated from the metal in an ore.