Terminology Series P

​The Oil and Gas industry is home to a host of industry-specific vocabulary and new terminology. To help get you clued up, we’ve put together our “Oil and Gas terminology series”.

Here, we look at the letter "P", and some words associated with the Oil and Gas sector.


Typically refers to liquid crude oil - a complex mixture of naturally occurring hydrocarbon compounds which are found in rock. The colour, odour, sulphur content, gravity and viscosity varies considerably in petroleum found in different areas.


The capability of a rock to allow passage of fluids through it, usually measured in “millidarcies” or “darcies”.


An offshore structure that is permanently fixed to the seabed. In the context of Oil, this structure is part of the system used to extract oil from the ground.

Proven field

An oil and/or gas field whose physical extent and estimated reserves have been effectively determined.

Proven reserves

Reserves which on the available evidence are judged to be technically and economically producible (i.e. having a better than 90% chance of being produced).

Primary recovery

Recovery of oil or gas from a reservoir purely by using the natural pressure in the reservoir to force the oil or gas out of the wells and up to the surface.

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