Gas or liquid fuel made from plant material (biomass). Examples of biofuel include alcohol (from fermented sugar), biodiesel from vegetable oil, and wood.
Mineral material that precipitates from water and fills the spaces between grains, holding the grains together.
A measurement of the carbon content of coal; higher-rank coal forms at higher temperatures.
Something that can be used to produce work; in a geologic context, a material (such as oil, coal, wind, flowing water) that can be used to produce energy.
An energy resource such as oil or coal that comes from organisms that lived long ago, and thus stores solar energy that reached the Earth then.
The trapping of heat in the Earth's atmosphere by carbon dioxide and other greenhouse gases, which absorb infrared radiation; somewhat analogous to the effect of glass in a greenhouse.
A chain-like or ring-like molecule made of hydrogen and carbon atoms; petroleum and natural gas are hydrocarbons.
The waxy molecules into which the organic material in shale transforms on reaching about 100 ยกC. At higher temperatures, kerogen transforms into oil.
meltdown (of nuclear reactor)
The melting of the fuel rods in a nuclear reactor that occurs if the rate of fission becomes too fast and the fuel rods become too hot.
A solid composed almost entirely of atoms of metallic elements; it is generally opaque, shiny, smooth, and malleable, and can conduct electricity.
The period of human history, including our own, so named because the economy depends on oil.
The degree to which a material allows fluids to pass through it via an interconnected network of pores and cracks.
The process during which chlorophyll-containing plants remove carbon dioxide from the atmosphere, form tissues, and expel oxygen back to the atmosphere.
The total volume of empty space (pore space) in a material, usually expressed as a percentage.
Rock with high porosity and permeability, so it can contain an abundant amount of easily accessible oil.
Sandstone reservoir rock in which less viscous oil and gas molecules have either escaped or been eaten by microbes, so that only tar remains.