A process in which sulfide minerals in newly exposed rock surfaces react with oxygen and rainwater to produce sulfuric acid, which causes chemical runoff as it leaches metals from the rocks. Acid drainage is a natural phenomenon, but mining greatly accelerates it by exposing many new surfaces.
electricityA secondary form of energy that can be transferred over long distances and applied to a variety of uses.EROI (energy returned on investment)The ratio determined by dividing the quantity of energy returned from a process by the quantity of energy invested in the process. Higher EROI ratios mean that more energy is produced from each unit of energy invested.energy conservationThe practice of reducing energy use as a way of extending the lifetime of our fossil fuel supplies, of being less wasteful, and of reducing our impact on the environment. Conservation can result from behavioral decisions or from technologies that demonstrate energy efficiency.energy efficiencyThe ability to obtain a given result or amount of output while using less energy input. Technologies permitting greater energy efficiency are one main route to energy conservation.fossil fuelsA nonrenewable natural resource, such as crude oil, natural gas, or coal, produced by the decomposition and compression of organic matter from ancient life.Hubbert's PeakThe peak in production of crude oil in the US, which occurred in 1970 just as Shell Oil geologist M. King Hubbert had predicted in 1956.methane hydrateAn ice like solid consisting of molecules of methane embedded in a crystal lattice of water molecules. Methane hydrates are being investigated as a potential new source of energy from fossil fuels.natural gasA fossil fuel composed primarily of methane, produced as a by product when bacteria decompose organic material under anaerobic conditions.net energyThe quantitative difference between energy returned from a process and energy invested in the process positive net energy values mean that a process produces more energy than is invested.oilpetroleumoil sandsDeposits that can be mined from the ground, consisting of moist sand and clay containing 1-20% bitumen, that some envision as a replacement for crude oil as this resource is depleted. Oil sands represent crude oil deposits that have been degraded and chemically altered by water erosion and bacterial decompositionoil shaleSedimentary rock filled with kerogen that can be processed to produce liquid petroleum. Oil shale is formed by the same processes that form crude oil, but occurs when kerogen was not buried deeply enough or subjected to enough heat and pressure to form oil.peak oilTerm used to describe the point of maximum production of petroleum in the world (or for a given nation), after which oil production declines. This is also expected to be roughly the midway point of extraction of the world's oil supplies.petroleumCrude Oil. However the term is also used to refer to both oil and natural gas together.primary extractionThe initial drilling and pumping of the most easily accessible crude oil.proven recoverable reservethe amount of a given fossil fuel in a deposit that is technologically and economically feasible to remove under current conditionsrefiningProcess of separating the molecules of the various hydrocarbons in crude oil into different sized classes and transforming them into various fuels and other petrochemical products.reserves to production ratioThe total remaining reserves of a fossil fuel divided by the annual rate of production.secondary extractionthe extraction of crude oil remaining after primary extraction by using solvents or by flushing underground rocks with water or steam.tar sandsoil sands
