OIL AND GAS TERMINOLOGY

• Treatment of oil-bearing limestone pr carbonate formations with a solution of hydrochloric acid and other chemicals to increase production. The acid is forced under pressure into the formation where it enlarges the flow channels by dissolving the limestone.

• Drilling using air as the circulation medium

• The angle, in degrees, at which a well is deflected from the vertical by means of a whipstock or other deflecting tool

• Arched stratified rock structure with layers dipping downward in opposite directions from the crest

• The cutting or boring element used in drilling oil and gas wells

• Uncontrolled flow of gas, oil, or other well fluids from a well during drilling due to formation pressure exceeding the pressure exerted by the column of drilling mud

• Hydraulically or mechanically actuated high-pressure valve installed at the wellhead to control pressure within the well

• Barrels of Oil Per Day

• Act of unscrewing one section of pipe from another section, particularly when drill pipe is being withdrawn for the well bore

• Act of completing and bringing a well into production

• Percussion method of drilling whereby the repeated pounding of a heavy bit makes the hole. Largely replaced by the rotary rig.

• Impermeable rock overlaying an oil or gas reservoir that tends to prevent migration of the reservoir fluids from the reservoir

• A well capable of production but lacking wellhead installations and a pipeline connection

• Steel pipe threaded together and cemented into a well as drilling progresses to prevent the wall of the hole from caving in during drilling and to provide a means of extracting oil/gas if the well is productive

• Heavy steel fitting that connects the first string of casing and provides housing for the slips and packing assemblies by which subsequent strings of casings are suspended and the annulus sealed off

• Gas dissolved in crude oil which emerges at the casing head when pressure is lowered

• Total feet of casing run in a well

• Cubic Feet of Gas

• Valves, pipes, and fittings assembled at the top of a completed well used to control the flow of oil and gas

• Cycling of the drilling fluid through the drill string and wellbore while drilling is temporarily suspended. This is done to condition the drilling fluid and wellbore before drilling proceeds

• To shut in (temporarily) a well that is capable of production

• Mixture of pentanes and heavier hydrocarbons that may be contaminated with sulfur compounds and is recovered or recoverable from and underground reservoir. It is gaseous in its virgin state but is liquid under the conditions at which its volume is measured.

• Depth that well must be drilled to fulfill the contract

• Cylindrical sample taken from a formation for the purpose of examination or analysis

• When the walls of a hole cave in

• Wellbore that has deviated from the vertical inadvertently

• Fragments of a rock dislodged by the bit and brought to the surface in the drilling mud

• Load-bearing tower like framework over an oil/gas well which holds the hoisting and lowering equipment

• Well drilled for oil and gas within a proven field or area for the purpose of completing the desired pattern of production

• Controlled drilling at a specified angle from the vertical

• Exploratory well which discovers a new oil/gas field

• Small house located on the rig floor or nearby that is used as an office for the driller and as a storage place for small tools

• When rig operations are temporarily suspended because of repairs or maintenance

• Hoisting mechanism on a drilling rig which spools off or takes in the drilling line and thus raises or lowers the drill string and bit

• Steel pipe, in approximately 30-foot (9-meter) lengths, screwed together to form a continuous pipe extending from the drilling rig to the drilling bit at the bottom of the hole. Rotation of the drill pipe and bit causes the bit to bore through the rock

• String of individual joints of pipe that extends from the bit to the kelly and carries the mud down to, and rotates, the bit

• Employee directly in charge of a particular crew, as opposed to a tool pusher, who is in charge of all the crews on a rig. Operation of drilling and hoisting equipment constitutes the driller’s main duties

• Generally refers to any well that does not produce oil or gas in commercial quantities

• Well drilled in unproven territory

• Geological term denoting a break in the subsurface strata

• Pressure registered at the wellhead of a flowing well

• Sedimentary bed or deposit composed substantially of the same minerals throughout and distinctive enough to be a unit

• Free gas, separate from, but overlaying an oil zone that occurs within the same producing formation as oil. Since gas is lighter, it occupies the upper part of the reservoir.

• Scientist whose duties consist of obtaining and interpreting data dealing with the earth’s history and its life, especially as recorded in rocks

• Patented apparatus that automatically records the rate of penetration and depth during drilling operations

• Lowering the drill pipe into the wellbore

• Common term for wellbore

• Distinct layer of group of layers of rock

• Organic chemical compounds of hydrogen and carbon whose densities, boiling points, and freezing points increase as their molecular weights increase. The molecular structure of the most common petroleum hydrocarbon compounds varies from the simplest – methane, a constituent of natural gas – to the very heavy and complex.

• Drilling of wells according to a planned pattern and spacing to achieve full production from a new field

• One length of drill pipe of casing

• Point at which a well is to be drilled. Commonly termed “well site.”

• Systematic recording of data

•  = 000 Example – 1 MCFG is 1,000 units of gas

• Act of screwing a single joint of drill pipe into the wellbore. The additions of this joint of pipe permits deepening of hole the length of the joint added or about 30 feet (9 meters.)

• Refers to progress being made at a given time when the bit is rotating and the wellbore is being deepened. In other words, drilling.

• Hoisting of the drill string out of, and returning it into, the wellbore. This is done for the purpose of changing bits, preparing to take a core, etc.

• Act of screwing a joint into another section of pipe

• Natural movement of oil or gas within or out of a formation

• Completion of a well in such a way that production is obtained from several different formations

• Well location adjoining another well site

• Loosely defined term referring to an area where oil is found. May also include the oil reservoir, the surface and wells, and production equipment.

• Uncased part of a well

• Person, whether proprietor or lessee, who actually operates the well. Generally, the oil company by whom the drilling contractor is engaged.

• A piece of downhole equipment that consists of a sealing device, a holding or setting device, and an inside passage for fluids

• Producing formation, or that formation which represents the objective of drilling

• To pierce holes through well casing within an oil or gas-bearing formation by means of a perforating gun lowered down the hole and fired electrically from the surface. The perforations permit production from a formation that has been cased off.

• Capacity of a porous rock formation to allow fluid to flow within the interconnecting pore network

• Oilfield tubular goods such as casing, drill pipe, tubing, or pipeline

• Object or device that serves to block a hole or passageway such as a cement plug in a borehole

• Act of placing cement plugs in a hole to prevent unwanted vertical migration in an abandoned well

• Volume of pore spaces between mineral grains expressed as a percentage of the total rock volume. Thus porosity measures the capacity of the rock to hold oil, gas, or water.

• Actual or maximum volume of oil and/or gas that a well is capable of producing

• The operation of bringing the well fluids to the surface and separating them, and storing, gauging, and otherwise preparing product for the pipeline. Also refers to the amount of oil or gas produced over a given period

• Porous, permeable sedimentary rock structure or trap containing oil and/or gas. A reservoir can contain more than one pool.

• The derrick, drawworks, and attendant surface equipment of a drilling or work over unit. (Several types of rigs should be included such as deep, shallow, stratigraphic, etc.)

• Act of getting a rig assembled and ready to start drilling

• Method of fracturing subsurface rock formations by injection of fluid and sand under high pressure to increase permeability. Fractures induced in the rock by the hydraulic pressure are kept open by the grains of sand.

• Apparatus used to measure and record vibrations in the earth. It is used to detect possible oil-bearing structures.

• Installation of steel pipe or casing in a wellbore, normally cemented in place by surrounding it with a wall of cement

• Commencement of actual drilling of well

• Well drilled adjacent or near to proven well to ascertain the limits of the reservoir

• Subsurface formation created by sedimentation that might trap an accumulation of oil and/or gas

• The entire length of casing, tubing, or drill pipe

• Subsurface geological feature capable of acting as a reservoir for oil and/or gas

• First set of casing set in well

• Operation using a swab to bring well fluids to the surface when the well does not flow naturally

• Making a trip; operation of hoisting pipe out of, and returning it to, the wellbore

• Contract under which contractor carries out and completes his assignment for a fixed fee, as opposed to working on a per diem basis

• Finish the work on a well and bring it to a productive state

• Recording information about subsurface geologic formations; methods include records kept by the driller, mud and cutting analysis, drill stem tests, electric and radioactivity procedures

• The hole made by a drilling bit

• Well drilled in unproven territory

• Time period that drilling is suspended while the cement used to hold casing in the wellbore hardens

• To carry out remedial operations on a producing well with the intention of restoring or increasing production