Abandoned Well

Converting a drilled well to a condition that can be left indefinitely without further attention and which will
not damage fresh water supplies or potential petroleum reservoirs.

Accord Implementation Acts

The Canada-Newfoundland Atlantic Accord Implementation Act, S.C. 1987, c.3 and the Canada-Newfoundland Atlantic Accord Implementation (Newfoundland) Act, R.S.N. 1986, c. 37. The federal and
provincial “mirror” legislation implements the provisions of the 1986 Canada-Newfoundland Atlantic
Accord and governs all petroleum activities that take place in the offshore area.

Certificate of Fitness

A certificate issued by a certifying authority stating that a design, plan or facility complies with the
relevant regulations or requirements, is fit for purpose, and can be operated safely and without posing a
threat to the environment.

Certifying Authorities

Organizations designated under the Newfoundland Offshore Certificate of Fitness Regulations to conduct
examinations of designs, plans and facilities and to issue Certificates of Fitness.

Commingled Production

Production of petroleum from more than one pool through a common wellbore or flowline without
separate measurement of the petroleum.

Common Mid-Point Kilometre

A seismic vessel towing multiple streamers (3D) will simultaneously collect a number of seismic profiles
in the direction of the ship’s track. Thus for each sail kilometre of the vessel, several kilometres of data
are acquired.


The activities necessary to prepare a well for the production of oil or gas.


A mixture of substances, most of which are pentanes and heavier hydrocarbon components, that is
recovered or is recoverable at a well from an underground reservoir and that may be gaseous in its virgin
reservoir state but is liquid in the conditions under which its volume is measured or estimated.

Conversion Factors

1 cubic metre = 6.2898 barrels (US)
1 kilometre (km) = 0.62137 miles
1 hectare = 2.471 acres
1 kPa (Kilopascal) = 0.145 psi


A cylindrical sample taken from a formation for geological analysis. Usually a conventional core barrel is
substituted for the bit and procures a sample as it penetrates the formation.


Chips and small fragments of rock produced by drilling that are circulated up from the drill bit to the
surface by drilling mud.

Delineation Well

Well drilled after a discovery well to determine the areal extent of a reservoir.

Development Well

A well drilled for natural gas or crude oil within a proven field or area for the purpose of completing the
desired pattern of production or a well into which fluids and/or gas is injected to increase or maintain
reservoir pressure.

Exploratory Well

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


A general surface area underlain or appearing to be underlain by one or more pools, including the
subsurface regions vertically beneath.


The term for the primary unit in stratigraphy consisting of a succession of strata useful for mapping or
description which possesses certain distinctive lithologic and other features, i.e. the Hibernia Formation.


Floating Production, Storage and Offloading vessel.

Gas Cap

A free-gas phase overlying an oil zone and occurring within the same reservoir as the oil.


Gravity Based Structure


Gas to Oil Ratio; a measure of the volume of gas produced with oil.


The gravity of crude oil, indicating the proportion of large, carbon-rich molecules, generally measured in
kilograms per cubic metre or degrees on the American Petroleum Institute (API) gravity scale.

Geophysical Survey

Searching and mapping the subsurface structure of the earth’s crust using geophysical methods (e.g.
seismic) to locate probable reservoir structures capable of producing commercial quantities of natural
gas and/or crude oil.

Hazardous Occurrences

A high-potential near miss (i.e., an incident that did not result in a reportable injury).


Any preventable, unplanned, work-related event or exposure or series of events or exposures that result
in or have the potential to result in harm to personnel and/or significant damage to equipment or


The process of pumping gas or water into an oil-producing reservoir to provide a driving mechanism for
increased oil production.


A diving installation, a drilling installation, a production installation or an accommodation installation.


This symbol is used in petrophysical and reserves calculations to represent the maximum permeability of
a rock formation.

Natural Gas Liquids

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


The holder of an authorization to conduct petroleum activities in the offshore area.


The science of measuring rock properties and establishing relationships between these properties based
on data obtained from various logging tools and methods, and from drill cores.


A natural underground reservoir containing or appearing to contain an accumulation of petroleum that is
separated or appears to be separated from any other such accumulation.


The volume of the pore space expressed as a percent of the total volume of the rock mass.

Produced Water

Water associated with oil and gas reservoirs that is produced along with the oil and gas.


The amount of oil and gas produced in a given period.

Productivity Index

The ratio of the rate of production to the pressure drawdown (the difference between static and flowing
bottom-hole pressures) at the midpoint of the producing interval.

Reportable Injury

Any employment injury or an occupational disease that prevents an employee from reporting for work or
from effectively performing all the duties connected with the employee’s regular work on the following
day, whether or not that day is a working day for that employee; results in a loss by an employee of a
body member or part thereof or in a complete loss of its usefulness, or results in the permanent
impairment of a body function of an employee.

Reportable Injury Rate

Rate of injuries per million person hours worked.

Recovery Factor

The percentage of total hydrocarbons expected to be produced from a reservoir, well or field over its
entire production lifespan.


The volumes of hydrocarbons proven by drilling, testing and interpretation of geological, geophysical and
engineering data, that are considered to be recoverable using current technology and under present and
anticipated economic conditions. Hibernia and Terra Nova are classified as reserves.


A porous, permeable rock formation in which hydrocarbons have accumulated.


The volumes of hydrocarbons, expressed at 50% probability of occurrence, assessed to be technically
recoverable that have not been delineated and have unknown economic viability.

Solution Gas

Lighter hydrocarbons that exist as a liquid under reservoir conditions, but become a gas when pressure
is reduced as the reservoir is produced.


To start the drilling of a well.

Suspended Well

A well in which drilling or producing operations have temporarily ceased.

Synthetic Based Mud

Drilling mud in which the continuous phase is a synthetic fluid that should have a total polycyclic aromatic hydrocarbon concentration of less than 10 mg/kg, be relatively nontoxic in marine environments and have the potential to biodegrade under aerobic conditions.

Test Rate

Rate of gas, oil and/or water flow during a drill-stem test.


Operations on a producing well to restore or increase production.