BIOGAS: gas derived from the anaerobic decomposition of organic matter.
BIOMASS: plant material used to make natural gas.
BTU: British Thermal Unit; the amount of energy needed to raise the temperature of one pound of water one degree Fahrenheit.
BUTANE: a valuable by-product gas found in natural gas.
CARBON: one of the elements, along with hydrogen, which make up natural gas.
CARBON DIOXIDE: colorless, odorless, nontoxic, incombustible gas, CO2; present in the atmosphere and formed during respiration and burning any fuel.
CARBON MONOXIDE:  a toxic gas, CO; formed as a product of the incomplete combustion of carbon.
CITY GATE:  distribution point where the natural gas is measured and sold to local natural gas companies.
COAL: a black, solid fossil fuel that is burned to make heat.
COAL GASIFICATION: process in which coal is heated and changed into a vapor to be burned as a fuel.
COAL SEAM:  a bed of coal.
COGENERATION: process by which electricity and useful heat are produced from a single source.
COMBUSTION: or burning, the sequence of chemical reactions between a fuel and an oxidant producing heat and light.
COMPRESSOR: large machines used to force natural gas through long transmission pipelines.
CONSERVATION: using something, like energy or water, wisely instead of wasting it.
CONSUMPTION: the using up of goods or services, either by consumers or in the production of other goods.
CUBIC FOOT: unit used to measure the volume of natural gas.
DEMAND: the quantity of a commodity wanted at a specific price and time.
DEPOSIT: body of natural gas trapped under- ground.
DERRICK: a tall tower over a gas well to sup- port the drill and for lowering pipe into the well.
DISTRIBUTION PIPELINE:  small pipeline used by gas companies to move natural gas around towns and cities to customers.
ECONOMY: relating to the production, distribution and consumption of goods and services.
ENERGY: the ability to do work.
ENVIRONMENT: all external conditions and influences affecting the life, development, and the survival of an organism.
ETHANE: a colorless, odorless, flammable gas, C2H6, present in natural gas.
FLAMMABLE: capable of being ignited.
FOSSIL FUEL: any combustible organic material, as oil, coal or natural gas, formed by the decomposition of prehistoric organisms.
FRACKING: hydraulic fracturing, using pressurized water to create fractures in rock allowing contained oil and natural gas to escape and flow out of a well.
FUEL CELL: a device in which fuel and oxygen are combined to produce chemical energy that is converted directly into electricity.
GAS: fluid form of matter that expands to fill its container.
GEOLOGIST:  scientist who studies origin, history, structure and composition of the earth, key in locating underground energy deposits.
GRAVITY MAPPING: process used in locating natural gas which determines thickness of rock layers and identifies base rock topography.
HYDROGEN: one of the elements, along with carbon, that make up natural gas; the lightest element.
IMPERMEABLE: relating to a material (or rock layer) through which substances such as liquids or gases cannot pass.
LIQUEFIED NATURAL GAS: (LNG) natural gas cooled to a very low temperature so that it becomes a liquid, which requires much less storage room.
LIQUID: matter that flows.
MAGNETIC: having the property of attracting like material.
MAGNETIC MEASUREMENT: method used in locating natural gas that measures the magnetic field of base rock to determine how much sediment is lying above it.
MERCAPTAN: an odorant added to natural gas to warn of leaks.
METER: device used for measuring flowing gas in units of cubic feet.
METHANE: major compound in natural gas: one atom of carbon, four atoms of hydrogen.
NATURAL GAS:  fossil fuel which comes from the ground, is thin like air and burns; used to produce heat for furnaces, water heaters, ranges and other natural gas appliances.
NATURAL PROCESSES:  produced or existing in nature, not artificial or man-made; natural forces: wind, water, etc.
NITROGEN: colorless, odorless, gaseous element that is a component of natural gas.
NONPOROUS ROCK: hard, solid rock that acts as a cap over sedimentary rock to prevent gas from rising to the earth’s surface and escaping.
NONRENEWABLE: any natural resource that requires ages of natural processes to produce and cannot, therefore, be replaced.
OFFSHORE DRILLING: drilling in the ocean off the coast for natural gas or other resources.
ORGANIC: plant and animal material.
PERMEABLE: having pores that permit liquid or gases to pass through.
PILOT LIGHT: a small permanent flame used to ignite gas at a burner.
PIPELINE: a line of pipe with pumps, valves, and control devices for conveying natural gas.
POLLUTION: waste material discarded or discharged into the earth, air, or water that is harmful to the environment.
POROUS ROCK: rock that has tiny holes that hold natural gas much as a sponge holds water; gas can flow through porous rock until stopped by a layer of nonporous rock.
PROCESSING: removing impurities and useful products from the raw gas that comes from the ground so it can be burned cleanly in homes and businesses.
PROPANE: a valuable by-product gas found in natural gas.
PROVED RESERVES: deposits of natural gas that have been discovered but not removed from the ground.
REGULATIONS: laws, rules, or other orders prescribed by authority to regulate conduct; implementing best practices to minimize environmental and social impacts.
RENEWABLE: capable of being replaced or replenished, able to use again.
RESERVOIR: underground area where gas can be stored for future use.
ROTARY DRILL: equipment that cuts through rock to reach deep underground deposits of natural gas.
SEISMIC SOUND WAVE REFLECTION: measures the time it takes sound waves to reach various rock units that reflect acoustic energy, creating a “slice of earth” view; used in locating natural gas deposits.
SOLID: compact matter that keeps its form.
SOURCE ROCK:  rock from which oil or natural gas is generated from organic materials.
SUPPLY: the availability of a desired commodity.
SYNTHETIC: artificial, such as synthetic products made from fossil fuels.
THERM: unit used to measure the heating value of natural gas.
TRANSMISSION PIPELINE: large pipelines used to move natural gas from wells to cities and towns.
UNCONVENTIONAL NATURAL GAS: natural gas derived from sources other than conventional petroleum formation.
VALVE: a device that regulates the flow of natural gas.
VAPOR:  normal state of natural gas, rather than solid or liquid.
VENTILATE: to expose to fresh air.
WELL: hole drilled in the ground to remove natural gas.
WILDCAT DRILLING: drilling for natural gas in new areas where no one has ever found fossil fuels before.