Block: Refers to a contiguous leashold position.

Development well: A well drilled within the area of an oil or gas resevoir known to be productive.

Directional drilling: (sometimes known as slant drilling outside the oil industry) is best described in plain English as follows, the directional driller will drill down to a certain feet and then they drill at an angle to reach a certain distance.

Dry Hole: A well found to be incapable of producing oil or gas in sufficient quantities to justify completion.

Exploration: Various methods of optimizing oil and gas production or establishing additional reserves from producing properties through additional drilling or the application of new technology.

Exploratory well: A well drilled in an unproved area, either to find a new oil and gas reservoir or to extend a known reservoir.

Field: A geographical area under which one or more oil or gas reservoirs lie.

Formation: An identifiable layer of rock named after its geographical location and dominant rock type.

Gross acres: The total number of acres in which one owns a working interest.

Lease: A legal contract that specifies the terms of the business relationship between an energy company and a landowner or mineral rights holder on a particular tract.

Permeable: Having pores or opening that permit liquid or gases to pass through.

Porous: A formation that possesses or is full of pores, permeable to fluids.

Production: Natural resources, such as oil or gas, taken out of the ground. --Gross production: Total production before deducting royalties. --Net production: Gross production, minus royalties, multiplied by one's fractional working interest.

Prospect: An area designated for the potential drilling of development or exploratory wells.

Resevoir: A rock formation or trap containing oil and/or gas.

Royalty: The owner's share of the value of minerals (oil and gas) produced on the property.

Undeveloped acreage: Lease acreage on which wells have not been drilled or completed to a point that would permit the production of commercial quantities of oil or gas.

Unit: A continuous parcel of land deemed to cover one or more common reservoirs, as determined by state or federal regulations.  Unit interest owners generally share proportionally in cost and revenues.