The Canadian Association of Petroleum Producers (CAPP) is the voice of the upstream oil and natural gas industry in Canada.



Converting a drilled well to a condition that can be left indefinitely without further attention and will not damage freshwater supplies, potential petroleum reservoirs or the environment.



Equipment to process or store crude oil from one or more wells.


A light aromatic hydrocarbon, which occurs naturally as a part of oil and natural gas activity. It's considered to be a non-threshold carcinogen and is an occupational and public health concern.


Petroleum in semi-solid or solid forms.

Benchmarking measures

Data and information used as a point of reference against which industry performance is measured.


Centrifugal pump

A rotating pump, commonly used for large-volume oil and natural gas pipelines, that takes in fluids near the centre and accelerates them as they move to the outlet on the outer rim.

Coalbed methane (CBM)

Natural gas generated and trapped in coal seams.


Hydrocarbons, usually produced with natural gas, which are liquid at normal pressure and temperature.

Conventional crude oil

Petroleum found in liquid form, flowing naturally or capable of being pumped without further processing or dilution.

Criteria air contaminants (CAC)

Emissions of various air pollutants that affect our health and contribute to air pollution problems such as smog. CACs are tracked by Environment Canada.

Cumulative effects

Changes to the environment caused by an activity in combination with other past, present and reasonably foreseeable human activities.

Cumulative production

Production of oil or gas to date.



The heaviness of crude oil, indicating the proportion of large, carbon-rich molecules, generally measured in kilograms per cubic metre (kg/m3) or degrees on the American Petroleum Institute (API) gravity scale; in Western Canada oil up to 900 kg/m3 is considered light to medium crude — oil above this density is deemed as heavy oil or bitumen. scale.

Development well

A well drilled in or adjacent to a proven part of a pool to optimize petroleum production.

Directional (deviated) well

A well drilled at an angle from the vertical by using a slanted drilling rig or by deflecting the drill bit; directional wells are used to drill multiple wells from a common drilling pad or to reach a subsurface location beneath land where drilling cannot be done.

Discovery well

An exploratory well that encounters a previously untapped oil or gas deposit.

Downstream sector

The refining and marketing sector of the petroleum industry.


Enhanced oil recovery (EOR)

Any method that increases oil production by using techniques or materials that are not part of normal pressure maintenance or water flooding operations. For example, natural gas can be injected into a reservoir to "enhance" or increase oil production.

Established reserves

The portion of the discovered resource base that is estimated to be recoverable using known technology under present and anticipated economic conditions. Includes proved plus a portion of probable (usually 50 per cent).

Exploratory well

A well into an area where petroleum has not been previously found or one targeted for formations above or below known reservoirs.



The surface area above one or more underground petroleum pools sharing the same or related infrastructure.


The controlled burning (flare) or release (vent) of natural gas that can't be processed for sale or use because of technical or economic reasons.

Flow line

Pipe, usually buried, through which oil or gas travels from the well to a processing facility.


Glycol Dehydrator

Field equipment used to remove water from natural gas by using triethylene glycol or diethylene glycol.


Heavy crude oil

Oil with a gravity below 28 degrees API.

Horizontal drilling

Drilling a well that deviates from the vertical and travels horizontally through a producing layer.

Hot water process

A method for separating bitumen from oil sand using hot water and caustic soda, developed by Karl Clark of the Alberta Research Council.


Infill drilling

Wells drilled between established producing wells on a lease in order to increase production from the reservoir.

Initial established

Established reserves before production.

Injection well

A well used for injecting fluids (air, steam, water, natural gas, gas liquids, surfactants, alkalines, polymers, etc.) into an underground formation for the purpose of increasing recovery efficiency.

In situ

In its original place; in position; in situ recovery refers to various methods used to recover deeply buried bitumen deposits, including steam injection, solvent injection and firefloods.





Legal document giving an operator the right to drill for or produce oil or gas; also, the land on which a lease has been obtained.

Light crude oil

Liquid petroleum that has a low density and flows freely at room temperature.


Calcium carbonate-rich sedimentary rocks in which oil or gas reservoirs are often found.


Medium crude oil

Liquid petroleum with a density between that of light and heavy crude oil.


The principal constituent of natural gas; the simplest hydrocarbon molecule, containing one carbon atom and four hydrogen atoms.

Middle distillates

Medium-density refined petroleum products, including kerosene, stove oil, jet fuel and light fuel oil.


The processing, storage and transportation sector of the petroleum industry.

Miscible flooding

An oil recovery process in which a fluid, capable of mixing completely with the oil it contacts, is injected into an oil reservoir to increase recovery.

Mud (also drilling mud)

Fluid circulated down the drill pipe and up the annulus during drilling to remove cuttings, cool and lubricate the bit, and maintain desired pressure in the well.


Natural gas liquids

Liquids obtained during natural gas production, including ethane, propane, butanes and condensate.


Oil sands

A deposit of sand saturated with bitumen.


The company or individual responsible for managing an exploration, development or production operation.


Ground-level ozone is a colourless gas that forms just above the earth's surface.


Particulate matter

Refers to microscopic solid or liquid particles that remain suspended in the air for some time.


The capacity of a reservoir rock to transmit fluids; how easily fluids can pass through rock.


A naturally occurring mixture composed predominantly of hydrocarbons in the gaseous, liquid or solid phase.

Pinnacle reef

A conical formation, higher than it is wide, usually composed of limestone, in which hydrocarbons might be trapped.


A natural underground reservoir containing an accumulation of petroleum.


The volume of spaces within rock that might contain oil and gas (like the amount of water a sponge can hold); the open or void space within rock ・usually expressed as a percentage of the total rock volume. Thus porosity measures the capacity of the rock to hold natural gas, crude oil or water.

Primary recovery

The production of oil and gas from reservoirs using the natural energy available in the reservoirs and pumping techniques.


Government allocation of demand among pools and wells; pipeline allocation of demand among shippers.



Remaining established

Initial established minus cumulative production.

Reformulated fuels

Gasoline, diesel or other fuels which have been modified to reflect environmental concerns, performance standards, government regulations, customer preferences or new technologies.


A rupture is an instantaneous tearing or fracturing of the pipeline material that immediately impairs the operation of the pipeline. Leaks can be an opening, crack or hole in a pipeline causing some product to be released, but not immediately impairing the operation of the pipeline.


The owner's share of production or revenues retained by government or freehold mineral rights holders. In natural gas operations, the royalty is usually based on a percentage of the total production.



A compacted sedimentary rock composed mainly of quartz or feldspar; a common rock in which oil, natural gas and/or water accumulate.

Secondary recovery

The extraction of additional crude oil, natural gas and related substances from reservoirs through pressure maintenance techniques such as waterflooding and gas injection.

Sedimentary basin

A geographical area, such as the Western Canada Sedimentary Basin, in which much of the rock is sedimentary (as opposed to igneous or metamorphic) and therefore likely to contain hydrocarbons.

Seismic Studies

Refers to studies done to gather and record patterns of induced shock wave reflections from underground layers of rock, which are used to create detailed models of the underlying geological structure.


Rock formed from clay.

Solution gas

Natural gas that is found with crude oil in underground reservoirs. When the oil comes to the surface, the gas expands and comes out of the solution.

Sour gas

Natural gas at the wellhead may contain hydrogen sulphide (H2S), a toxic compound. Natural gas that contains more than one per cent of H2S is called sour gas. About 30 per cent of Canada's total natural gas production is sour, most of it found in Alberta and northeast British Columbia.


Spills include accidental release of crude oil, produced water or other hydrocarbon products from well sites, batteries or storage tanks. These spills can affect land, vegetation, water bodies and groundwater.


Industry activities often affect surrounding areas and populations. People with an interest in these activities are considered stakeholders. They may include nearby landowners, municipalities, Aboriginal communities, recreational land users, other industries, environmental groups, governments and regulators.

Steam-assisted gravity drainage (SAGD)

A recovery technique for extraction of heavy oil or bitumen that involves drilling a pair of horizontal wells one above the other; one well is used for steam injection and the other for production.

Steam injection

An improved recovery technique in which steam is injected into a reservoir to reduce the viscosity of the crude oil.


A yellow mineral extracted from petroleum for making fertilizers, pharmaceuticals and other products.

Sulphur dioxide

A major component of a group of airborne contaminants termed "acidifying emissions."

Sulphur recovery

Sour gas is processed at recovery plants to extract sulphur for sale to fertilizer manufacturers and other industries in Canada and overseas. The average rate of sulphur recovery at Alberta's sulphur recovery plants has improved from 97.5 per cent in 1980 to 98.8 per cent in 2000.

Sweet oil and gas

Petroleum containing little or no hydrogen sulphide.

Synthetic crude oil

A mixture of hydrocarbons, similar to crude oil, derived by upgrading bitumen from oil sands.


Tar sands

Another name for oil sands. A deposit of sand saturated with bitumen.

"Oil Sands or Tar Sands

The hydrocarbon mixtures found in northern Alberta have historically been referred to as tar, pitch or asphalt. However, 'oil sands' is now used most often to describe the naturally occurring bitumen deposits. This helps distinguish it from the other terms, which are associated with distilled or man-made products, such as the mixtures used to pave roads.

Oil sands is an accurate term because bitumen, a heavy petroleum product is mixed with the sand. It makes sense to describe the resource as oil sands because oil is what is finally derived from the bitumen."

Tertiary recovery

The third major phase of crude oil recovery that involves using more sophisticated techniques, such as steam flooding or injection of chemicals, to increase recovery.

Tight gas

Gas with very low flow rates. Found in sedimentary layers of rock that are cemented together so tightly that it "greatly hinders" the extraction. Getting tight gas out usually requires enhanced technology like "hydraulic fracturing" where fluid is pumped into the ground to make it more permeable. The National Energy Board estimates Canada has 300 trillion cubic feet (tcf) of tight gas in place.


A mass of porous, permeable rock – sealed on top and both sides by non-porous, impermeable rock – that halts the migration of oil and gas, causing them to accumulate.


Ultimate potential

An estimate of recoverable reserves that will have been produced by the time all exploration and development activity is completed; includes production-to-date, remaining reserves, development of existing pools and new discoveries.

Undiscovered recoverable resources

Those resources estimated to be recoverable from accumulations believed to exist based on geological and geophysical evidence but not yet verified by drilling, testing or production.


The process of converting heavy oil or bitumen into synthetic crude oil.


The companies that explore for, develop and produce Canada's petroleum resources are known as the upstream sector of the petroleum industry.



The process of producing seismic shock waves with "thumpers" or vibrator vehicles.


The resistance to flow, or "stickiness" of a fluid.

Volatile organic compounds (VOCs)

Gases and vapours, such as benzene, released by petroleum refineries, petrochemical plants, plastics manufacturing and the distribution and use of gasoline; VOCs include carcinogens and chemicals that react with sunlight and nitrogen oxides to form ground-level ozone, a component of smog.



A hole drilled or bored into the earth, usually cased with metal pipe, for the production of gas or oil.


A well drilled in an area where no oil or gas production exists.