Technical
Thesaurus oil & gas
E
E.I.S.
An environmental impact
statement which is required by many environ- mental authorities before a
project can proceed.
Easting
The distance a craft makes
good to the east. The opposite is westing. In a cartesian reference system the
value of one coordinate, usually ex- pressed in metres used, measured from the
central meridian in east-west direction; e.g. in the UTM system.
EBCDIC
Extended Binary Coded
Decimal Interchange Code. The data format is used in the seismic industry for
data acquisition and storage.
ECDIS
Electronic Chart Display
and Information System.
Echo sounder
An acoustic water depth
measurement instrument, hull mounted or tracked to the hull of a vessel; raw
data is corrected for water velocity, ship draft and tidal variations, and
often digitised for automated bathymetric chart production. Recent development
of multibeam or swathe sounders are not in common use.
Echo sounding
Determination of the depth
of water by measuring the time interval between emission of a sonic or
ultrasonic signal and return of its echo from the bottom. Also called acoustic
sounding. See echo sounder.
Economic limit
The minimum rate to which
the production of a well may decline and still be profitable.
Economic project
A project that appears
likely to yield an acceptable net income after paying all costs, royalties,
taxes, etc.
Edge water
Water underlying and/or
marginal to an oil or gas reservoir.
Effective permeability
A measure of the ability of
a single fluid to flow through a rock when the pore spaces of the rock are not
completely filled or saturated with fluid. Compare absolute permeability and
relative permeability.
Effluent
Waste liquid, gas or vapour
from processes.
Elastomer
The basic building block
from which an elastic polymer is made.
Elastomer (synthetic)
An elastomer manufactured
from petrochemicals.
Electric logging
Technique, originally
devised by the Schlumberger brothers, in which electrical measurements are made
and recorded to the surface, while a series of electrodes or coils is caused to
traverse a bore hole. The resulting curves of response versus depth can be used
for purposes of geological correlation, for the recognition of some rock
properties, and for assessing the nature and amount of the fluids in the pores
of the rock.
Electrical drilling
A drilling method, used to
a certain extent in the former U.S.S.R., whereby the bit is rotated by a
down-the-hole electric motor attached to the drill pipe or hanging from a cable
in the borehole.
Electrodynamic brake
A device mounted on the end
of the drawworks shaft of a drilling rig. The electrodynamic brake (sometimes
called a magnetic brake) serves as an auxiliary to the mechanical brake when
the pipe is lowered into a well. The braking effect in the electrodynamic brake
is achieved by means of an interaction of electric currents with magnets, with
other currents, or with themselves.
Electromagnetic distance
measurement (EDM)
Any process or technique of
distance measurement which depends on a comparison of signals by
electromagnetic means.
Electronic barrel
Phrase used by traders to
describe crude oil or products dealt in over the screen on a Futures or similar
market. If the contract is allowed to mature and require physical delivery it
is described as being 'wetted'
Electronic chart
An integrated, interactive,
navigation information system, with which the user can display the hydrographic
and positional information that is required to conduct the safe navigation of
his vessel. It comprises hydrographic and cartographic data bases containing
information useful for navigation.
Element
A substance which cannot be
broken down into a more simple form.
Elevation
The vertical distance of a
point or a level, on or affixed to the surface of the Earth, measured from mean
sea level. The term elevation is sometimes used synonymously with altitude
which in modern use refers particularly to the distance of points of objects
above the Earth's surface. An area higher than its surroundings, as a hill.
Elevators
The clamps on the
travelling block which are attached to the drill pipe in order to raise or
lower it.
Emulsion
An intimate mixture of two
liquids which are not miscible, e.g. oil and water.
Emulsoid
Colloidal particles which
take up water.
Endothermic process
A process accompanied by
the absorption of heat.
Engineering plastic resins
A class of petroleum-based
materials which can be moulded to form plastic artefacts or used as the basis
of adhesives.
Enhanced oil recovery
A process whereby oil is
recovered other than by the natural pressure in a reservoir. See secondary
recovery, tertiary recovery.
Entrained oil
Oil occurring as part of a
gas stream, but as a relatively small percentage of total flow.
Environment of deposition
The environment in which
basin sediments were originally deposited. The two principal environments are
marine (under the sea) and continental (inland from the sea). The paralic
environment refers to the marine borders. Glacial refers to sediments deposited
by ice action in either a marine or continental environment. Continental
includes lacustrine (pertaining to lakes) and deltaic (pertaining to river
deltas) and fluviatile (pertaining to rivers).
EPC
Name of commonly used
analogue paper recorder.
EPIRB
Emergency Position
Indicating Radio Beacon. An emergency electronic signaling device that can be
detected by a satellite and over-flying aircraft.
Epoxide resins
Resins used as the resin
components of surface coatings of various sorts. They are usually made by
condensation of epichlorohydrin with a polyvalent alcohol or phenol. Examples
are the epikote resins called epon in the
Equity capital
Capital raised by issuing
shares to investors.
Error
The difference between an
observed or computed value of a quantity and the ideal or true value of that
quantity.
Error (gross)
The result of carelessness
or a mistake; may be detected through repetition of the measurement. Also
called blunder.
Error (standard)
The square root of the
arithmetic mean of squared deviations from the mean. Also called standard
deviations, when the deviations do not represent errors, or root mean square
error.
Error (systematic)
An error whose magnitude
changes in proportion to known changes in observational conditions. Also called
regular error.
Escape capsule:
A smaller completely
enclosed vessel used as a lifeboat for offshore structures.
Escape line
An inclined wireline
running from a point above the monkey or fourble board of the derrick down to a
ground anchor.
Escarpment
A cliff or relatively steep
slope that separates level or gently sloping areas of land.
Ethane
The saturated hydrocarbon
(alkane) with two carbon atoms in its molecule (C2H6); the second member of the
paraffin series -a gas under normal conditions.
Ethanol (ethyl alcohol)
A chemical produced by
fermentation or synthesised from ethane (C2H5OH); used as a raw material in a
wide range of industrial and chemical processes, e.g. the production of
acetaldehyde (CH3CHO).
Ethene (ethylene)
The simplest member of the
alkene series, containing two carbon atoms connected by a double (unsaturated)
bond (C2H4); an important raw material in the chemical and plastics industries.
Ethyl (radical, group)
The organic radical (or
group) formed by the removal of a single hydrogen atom from ethane (C2H5).
Ethylthioethanol
One of a class of
sulphur-containing compounds used widely in the synthesis of pesticides.
Evaporation
Conversion of a liquid to
vapour, without necessarily reaching the boiling point.
Evening tour
The shift of duty on a
drilling rig that starts in the afternoon and runs through the evening. Compare
daylight tour and graveyard tour.
Events
Data is recorded during the
inspection of a Structure through Events. Each Event has it's own template
through which data may be recorded. Each template ensures that data is recorded
quickly, accurately and using a consistent terminology. There are 29 Events,
which come preconfigured with Inspection Manager Eventing Module. You may
create your own customised Events to supplement this. e.g. Some of the Events
provided with Inspection Manager Eventing Module are: Anode, Burial, CP
Reading, Debris, Flooded Member, Marine Growth, Weld and Concrete.
Exothermic process
A process in which energy
in the form of heat is released.
Expansion factor
The radio location, factor
representing the degree to which the hyperbolae belonging to a given group of
hyperbolic lines of position move apart as the distance from the base line
increases.
Expansion joint
A section of piping
constructed in such a way as to allow for expansion and contraction of the pipe
connections without damaging the joints. Specially fabricated accordion-like
fittings are used as expansion joints in certain in-plant hook-ups where there
are severe temperature changes.
Expansion loop
A circular loop (omega
shaped) put in a pipeline to absorb expansion and contraction caused by heating
and cooling, without exerting a strain on pipe or valve connections.
Exploitation well
A well drilled to permit
more effective extraction of oil from a reservoir. It is sometimes called a
development well. See development well.
Exploration drilling
Drilling carried out to
determine whether hydrocarbons are present in a particular area or structure.
Exploration licence
A licence to explore for
oil or gas in a particular area issued to a company by the governing State.
Exploration phase
The phase of operations in
which a company searches for oil or gas by carrying out detailed geological and
geophysical surveys followed up where appropriate by exploratory drilling in
the most promising places.
Exploration rig
A structure used to carry
the equipment needed for exploratory drilling. See jack-up drilling rig,
semi-submersible rig and drillship.
Exploration well
See wildcat.
Explosion
A violent, uncontrolled
release of pressure causing noise and possibly accompanied by fire or evolution
of gases.
Exposed location single-buoy mooring (ELSBM)
A floating chamber anchored
near a production platform in order to serve as a flexible connection to a
tanker taking on oil from the platform; such a system has no storage capacity.
Also known as a single-buoy mooring (SBM) and single-point mooring (SPM).
Extender oil
An oil used to alter the
physical characteristics of synthetic rubber.
Extraction
The removal of a substance
from a mixture by the use of a selective solvent.
Extrapolation