Anticline: An anticline is a fold structure in which the sides of the fold slope apart. Its shape is concave downward. Deep underground, anticlines are highly desired by petroleum prospectors. The rock beds trap rising hydrocarbon fluids, allowing oil and gas to build up in the pore space of the anticline rocks. The largest oilfields occur in large, gentle anticlines in thick sedimentary rock sequences. http://geology.about.com/library/bl/images/blanticline.htm

API gravity: The gravity (weight per unit of volume) of crude oil expressed in degrees according to an American Petroleum Institute recommended system. The higher the API gravity, the higher the crude. High-gravity crudes are generally considered more valuable.
http://www.maverickenergy.com/lexicon.htm

BOP (blowout preventer): An assembly of heavy-duty valves attached to the top of a well casing to control pressure. http://www.maverickenergy.com/lexicon.htm

Casing Pipe: Used in oil wells to reinforce the borehole. Sometimes several casings are used, one inside the other. The outer casing, called the "surface pipe,' shuts out water and serves as a foundation for subsequent drilling.
http://www.maverickenergy.com/lexicon2.htm

Christmas tree: An assembly of valves, gauges, and chokes mounted on a well casinghead to control production and the flow of oil to the pipelines. http://www.maverickenergy.com/lexicon.htm

Core Sample: Cylindrical sample of rock taken from the ground by drilling for research and exploration purposes. http://www.nrcan.gc.ca/mms/scho-ecol/glos_e.htm

Crude oil: Liquid petroleum as it comes out of the ground. Crude oils range from very light (high in gasoline) to very heavy (high in residual oils). Sour crude is high in sulfur content. Sweet crude is low in sulfur and therefore often more valuable. http://www.maverickenergy.com/lexicon.htm#Cs

Derrick Tower: The centerpiece of the drill rig used for lifting and positioning the drilling bit and piping above the well head, and containing the machinery for turning the drilling bit around in hole. http://en.wikipedia.org/wiki/Derrick

Drill Rig: A structure housing equipment used to drill into underground reservoirs for water, oil, or natural gas. http://en.wikipedia.org/wiki/Drilling_rig

Gypsum: Gypsum is the more common name for a mineral compound called calcium sulphate dihydroxide, or sulphate of lime. Gypsum is generally found underground near deposits of limestone or other minerals formed by evaporation. http://www.wisegeek.com/what-is-gypsum.htm

Natural gas: A mixture of hydrocarbon compounds and small amounts of various nonhydrocarbons (such as carbon dioxide, helium, hydrogen sulfide, and nitrogen) existing in the gaseous phase or in solution with crude oil in natural underground reservoirs. http://www.maverickenergy.com/lexicon4.htm

Pipeline: A tube or system of tubes used for the transportation of oil or gas. http://www.maverickenergy.com/lexicon4.htm

Production: A term commonly used to describe taking natural resources out of the ground.
http://www.maverickenergy.com/lexicon4.htm

Pump Jack: Used to mechanically lift oil out of the well if there is not enough bottom hole pressure for the liquid to flow all the way to the surface. Also known as a Nodding Donkey or Horsehead Pump. http://en.wikipedia.org/wiki/Pumpjack

Raw Crude Oil: Crude oil direct from the wellbore, before it is treated in a gas separation plant. It usually contains nonhydrocarbon contaminants. http://www.glossary.oilfield.slb.com/Display.cfm?Term=raw%20crude%20oil

Seismic Source: A seismic source generates controlled seismic energy that is used in seismic surveys. The Digipulse Truck provides a pulse of energy that generates seismic waves, which travel through layers of rocks. The waves then reflect and refract to geophones. http://en.wikipedia.org/wiki/Seismic_source

Sour Crude or Gas: Oil or natural gas containing sulfur compounds, notably hydrogen sulfide a poisonous gas. http://www.maverickenergy.com/lexicon5.htm

Sweet crude: Crude oil with low sulfur content which is less corrosive, burns cleaner, and requires less processing to yield valuable products. http://www.maverickenergy.com/lexicon5.htm

Tank Battery: A group of tanks that are connected to receive crude oil production from a well. http://www.glossary.oilfield.slb.com/Display.cfm?Term=tank%20battery