Glossary

Glossary

This glossary more specifically relates to oil and gas exploration and production terms.

Deck (of a platform):
Horizontal surface placed on a jacket, supporting the facilities necessary for producing oil.
Delta:
Alluvial deposits at a river mouth.
Density:
Ratio of the mass of a given volume of a substance to the mass of an equivalent volume of water.
Derrick:
Metal tower erected vertically above a well for the purpose of lifting and lowering tubes and tools into the well.
Derrick-man:
Member of the drilling crew who works at the top of the derrick.
Desalting:
Removal of salt from crude oil. Desalting is preferably performed prior to commercialization of the crude, and must be performed prior to refining.
Development:
All operations and measures undertaken to bring a reservoir into production.
Diamond-tipped (tools):
Drill-bit or other tool whose cutting-edge has been hardened with manmade diamonds.
Directional drilling:
The most common drilling direction is vertical, but there may be various reasons for drilling obliquely.
Discharge (of oil):
Action of routing oil from the wells to the discharge flanges.
Discovery well:
A well in which an oil field is discovered during exploration.
Distillation:
This consists in converting a liquid into vapor, then condensing the resulting vapor back to into liquid in order to separate liquids from nonvolatile solids. Separation takes place according to the boiling range of each of the liquid's constituents.
Drill:
Making a hole by means of whatever mechanism.
Drill string:
Set of drilling tools, comprising pipes connected to each other, the bit, and the different tools. In drilling, the drill string is rotated by the rotary table.
Drilling foreman:
An experienced worker who operates the well derrick and oversees the drilling crew.
Drilling mud:
Mixture of water and special additives circulating within the well for the purpose of:
- cooling the drill-bit
- removing rock cuttings and transporting them back up to the surface
- preventing the well wall from caving in
- maintaining sufficient pressure at the well bottom to avoid hydrocarbon blowout.
Drilling superintendent:
Responsible for the proper execution of well-drilling operations.
Dynamic positioning:
Set of means for automatically keeping a ship constantly at a determined position, with neither chains nor cables, but using its own propulsion system only.
Dynamically-positioned ship:
A drilling ship equipped with several computer-activated propellers to keep the ship on station.