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Discover the IHRDC Energy Glossarybeta

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F

f-k domain

The frequency-wavenumber domain, obtained by Fourier transforming seismic data over both time and space.

F-K filters

Seismic data is typically in time and space domain. F-K filters convert the data to frequency and wave number domain.

f-k plot

A contoured display of seismic energy against frequency and wavenumber, separating events by their apparent velocity and direction.

fabric

The size, shape, arrangement and orientation of the components of a rock — grains, pores, cement and layering.

face alignment

Alignment judged by the angle between coupling faces.

face shield

A piece of protective equipment that protects the entire face from flying particles and liquids.

facepiece

The part of a respirator sealing to the face.

facial expression

The most closely read nonverbal channel, and largely involuntary.

facies

A rock unit with distinctive characteristics, formed under certain conditions of sedimentation reflecting a particular depositional environment or process.

facies analysis

Interpreting depositional environment from the character of the rock.

facies change

A lateral change in rock character, which can create a stratigraphic trap.

facies model

A conceptual arrangement of facies used to predict rock type between wells.

facies modeling

Building a reservoir model from facies bodies and the depositional environments they represent, rather than from property values alone.

facilitation

Guiding a group's process so it reaches a decision, without steering the content.

facilitator

The person running a workshop session, guiding the process rather than delivering content.

facility

(A) Any building, structure, installation, equipment, pipe or pipeline (including any pipe into a sewer or publicly owned treatment works), well, pit, pond, lagoon, ditch, storage container, motor vehicle, rolling stock, or aircraft, or

(B) Any site or area where a hazardous substance has been deposited, stored, disposed of, or placed, or otherwise come to be located; but does not include any consumer product in consumer use or any water-borne vessel.

facility piping

The pipework connecting process equipment within a facility.

factor

A number that is multiplied by another number.

factoring

An operation used to separate a common factor from terms in an expression.

factory bends

Short lengths of conduit that come bent in 90-degree and 45-degree angles.

Fahrenheit

A temperature scale with the freezing point of water at 32°F and the boiling point of water at 212°F.

failing fast

Testing cheaply and early so wrong ideas are abandoned before they are expensive.

failure envelope

The locus of stress states at which rock fails, from which safe mud weights are derived.

Fair Labor Standards Act (FLSA)

The United States statute setting minimum wage, overtime and child labor rules.

fair vs. unfair labour practice

Conduct permitted in labor relations against conduct the law prohibits.

fairway

The trend along which a particular geological feature — a sand body, a reservoir or a hydrocarbon accumulation — is expected to occur.

fall time

The time required for an output voltage step to change from 90% to 10% of its final value.

fallback

The alternative arrangement used if the primary one fails.

falloff

The pressure decline after injection stops, analyzed like a buildup test.

falloff test

A pressure test analyzing the decline recorded after an injection well is shut in.

false pressure

False pressure is the extrapolation of the pressure in a build-up test to a Horner time ratio of 1 for a well which has had some pressure depletion in its drainage area caused by the extended production of fluids. It is an intermediate step in estimating the average pressure in the drainage area of a development well.

Family and Medical Leave Act (FMLA)

The United States statute granting job-protected unpaid leave for family and medical reasons.

fan

A motor driven device used to increase the pressure of air so that it will flow through a ventilation system.

fan delta

A delta built where an alluvial fan enters standing water, coarse and steep.

fan shooting

A refraction technique with receivers arranged on an arc around a shotpoint, looking for early arrivals that betray a buried high-velocity body.

fan system

A system composed of a fan, any ducts connected to the fan, and other components that are associated with the fan.

fan wheel

The rotating part of a fan.

fanglomerate

Fanglomerate is a sedimentary rock that forms when sediments are deposited on alluvial fans and then cemented together over time. This is a type of conglomerate made up of particles ranging from gravel to silt and is characterized by a chaotic texture.

fann

The standard field viscometer, whose dial readings define mud rheology.

fann instrument

The standard field viscometer used to measure drilling fluid rheology.

Fann viscometer

A rotational viscometer that measures the viscosity and gel strength of drilling and completion fluids at fixed shear rates, read directly from a dial.

far offset

A long source-receiver separation, which carries the amplitude information that indicates fluid.

far water

Far water is the water which is not bound to the clays in the dual water model.

farad

The unit of capacitance, one coulomb stored per volt applied.

farm-in

The acquisition of part or all of an oil, natural gas or mineral interest from a third party.

farm-in / farm-out

An agreement under which the owner of a working interest in an oil and gas lease assigns a share of that interest to a third party in exchange for the third party's commitment to cover a portion of the capital expenditures. Generally, the assignee is required to perform seismic surveys or drill one or more wells in order to earn interest in the acreage. The assignee is said "to farm-in" while the assignor is said "to farm-out".

farm-out

The assignment of part or all of an oil, natural gas or mineral interest to a third party.

farmee

The party earning an interest in acreage by drilling a well or carrying costs on it under a farmout agreement.

farmor

The party that owns the leasehold and assigns part of it in return for the farmee's work commitment.

farmout agreement

A transfer of interest in return for the transferee funding drilling or other work.

FASB (Financial Accounting Standards Board)

The body that sets United States accounting standards.

fast diffusion

The regime in NMR where molecules cross the pore many times during the measurement, so relaxation depends on the pore's surface-to-volume ratio.

fast formation

A formation whose shear velocity exceeds the compressional velocity of the borehole fluid, so a shear headwave can be refracted along the wall.

fast Fourier transform

The algorithm computing a discrete Fourier transform in far fewer operations than the direct calculation, abbreviated FFT.

fast-formation arrival

Formation signal arriving at a cement bond log receiver before the casing signal, because the rock is faster than steel.

fast-neutron reaction

A neutron interaction at high energy in which the nucleus absorbs the neutron and emits particles or gamma rays.

fastener

A device used to attach one material to another (e.g., a screw, nut, or bolt).

fatigue management

Controlling working hours and rest so tiredness does not become a cause of error.

fatty acid

A long-chain organic acid derived from animal or vegetable fats and oils.

fatty-acid soap

The salt formed when a fatty acid reacts with lime or another metal base, the classic oil mud emulsifier.

fault

A planar fracture or discontinuity in a volume of rock, across which there has been significant displacement along the fractures as a result of earth movement.

fault circuit interrupter

A device opening the circuit when it detects current leaking to earth.

fault current

The current that exists when an unintended path is established between two or more conductors or between one or more conductors and ground.

fault drag

Fault drag refers to the deflection of curved markers adjacent to a fault.

fault heave

The heave of a fault is the horizontal component of the dip separation.

fault rollover and rollover anticlines

Fault rollovers and rollover anticlines form when the hanging wall slumps into the low pressure extensional zone associated with listric normal faulting.

fault throw

The throw of a fault is the vertical component of the dip separation.

fault trap

A structural trap whose closure depends on a fault sealing against the reservoir on the other side.

faulting

Fracturing with displacement, which can either trap hydrocarbons or let them escape.

faunal

Faunal refers to the study of animal fossils and their use in determining the age and history of rocks and the Earth.

faunal markers

Faunal markers are fossils or fossil fragments of plants or organisms that can be used to determine stratigraphy.

Faye correction

The free-air correction in gravity surveying, 0.3086 mGal per meter of elevation above the datum.

FD

Frequency domain — the representation of a signal as amplitude and phase against frequency rather than against time.

feasibility study

The assessment of whether a project is technically and commercially viable.

feathering

Lateral drift of a towed streamer under current, which displaces where the data was actually recorded.

federal banking agencies

The United States regulators supervising banks at federal level.

Federal Trade Commission (FTC)

The United States agency regulating competition and consumer protection.

fee-simple interest

Absolute ownership of a tract, surface and minerals together, with the right to use, lease or sell any part of it.

FEED

Front-end engineering and design – part of a project's life cycle.

feed (or feed material)

The initial material introduced to the reforming process (usually naphtha for high performance fuels).

feed gas chilling

Cooling incoming gas to drop out heavier components before it goes to sales.

feed preparation section

The section of an alkylation unit in which the feed is decontaminated.

feed tank

A tank that contains a feed stock used as a basic ingredient for products in one more process units; also called a charge tank.

feedback

A signal from a motor or monitoring device indicating the actual speed or operating condition. In amplifiers, the output signal fed back to the input, which is negative feedback if the output polarity is opposite to the input polarity.

feedback circuit

A circuit that provides a path for part of an amplifier's output to be returned to the input of the amplifier circuit.

feedback control

A basic form of closed loop process control in which the control action occurs after the process variable has deviated from set point, where the variable the system manipulates affects the controlled variable it monitors.

feedback loop

A circuit in which an output feeds back to affect the input, reinforcing or damping the behavior.

feedback resistor

The resistor returning part of an amplifier's output to its input, which sets its gain.

feeder circuit

The circuit supplying power to a distribution point or load.

feedforward

Control acting on a measured disturbance before it affects the process, rather than on the error afterward.

feedforward control

A type of control in which the system monitors conditions that would produce a process upset and compensates for them in advance to maintain stable controlled variables.

feedstock

The raw hydrocarbon input a process converts into a higher-value product.

feedstock cost

The cost of the input hydrocarbon, usually the largest element of a plant's operating cost.

feedwater

The water that is pumped into a boiler to replace the water that leaves as steam.

feedwater flow

The rate of water fed to a boiler, which must match steam production.

feedwater heater

An exchanger warming boiler feedwater with extraction steam, raising cycle efficiency.

feedwater regulating valves

Valves that control the flow of feedwater into the boiler to support normal boiler operation; also referred to as flow control valves.

feedwater system

The pumps, heaters and controls supplying a boiler with water.

feeler

A thin blade of known thickness used to measure a small gap.

feeler gauge

A precision measurement tool composed of a number of blades, each machined to an exact thickness and used alone or in combination to measure gaps and narrow spaces between surfaces. Also called a thickness gauge.

feldspar

A group of aluminum silicate minerals, abundant in igneous rocks and common as detrital grains in sandstone.

feldspar, feldspathic

Feldspars (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8) are a group of rock forming tectosilicate minerals.

felsic

Describing igneous rocks and minerals rich in quartz and feldspar, and therefore light in color and low in density.

fence diagram

A perspective display of several intersecting cross-sections, showing three-dimensional geological relationships on a flat page.

fence diagrams

Fence diagrams consist of a three-dimensional network of geological cross-sections drawn in two dimensions.

ferc

The United States regulator of interstate gas transport, LNG facilities and wholesale power.

Fermat's principle

The principle that a ray travels between two points along the path of stationary traveltime, which in practice is the minimum-time path.

ferric

Iron in its higher oxidation state, a corrosion product and scale component.

ferro-chrome lignosulfonate

Lignosulfonate treated with both iron and chromium compounds for greater thermal stability as a deflocculant, abbreviated FCL.

ferrous

Containing iron, and so subject to corrosion by acid gas.

ferrous sulfide

Iron sulfide, FeS, the black corrosion product formed where hydrogen sulfide attacks steel.

FFI

FFI (free fluid index) was the term used for the effective porosity in historical NMR log interpretation terminology.

FFT

Fast Fourier transform — the algorithm that computes a discrete Fourier transform in a fraction of the operations the direct calculation needs.

fiber LCM

Long, flexible fibrous lost circulation material that mats across a loss zone and holds finer particles behind it.

fiber lost-circulation material

Fibrous material added to mud to mat across and seal a loss zone.

fiber optic

A fiber optic cable uses thin flexible, fibers with glass cores through which signals can be sent with very little loss of strength.

fiber optic (adjective)

Fiber optic (as an adjective) is consisting of, or using, thin flexible, fibers with a glass core through which light signals can be sent with very little loss of strength.

fiber optic channel

A transfer trip communication channel in which a trip signal is converted to an optical signal and then reconverted to a trip signal by interface panels.

fiber rope

A type of rope that is made of natural or synthetic fibers that are twisted together into threads, which are then twisted together to form strands.

fibrous

Composed of fibers, as the lost circulation materials used to bridge fractures.

fiduciary responsibility

The duty to act in another's interest ahead of one's own.

field

An area consisting of a single reservoir or multiple geologically related reservoirs grouped on the same geological structural feature and/or stratigraphic condition. In electrical systems, the part of an AC generator that has DC power applied to create a magnetic field.

field coil

The coil producing the magnetic field in a machine.

field communicator

A hand-held device that communicates with 'smart' analog instruments over 4-to-20 milliamp loop wiring. Data can be downloaded into the communicator memory or entered on its keypad, and then downloaded to another field device.

field control rheostat

A variable resistor that is used in some systems of AC generator voltage control.

field development plan (FDP)

The document setting out how a discovery will be drilled, produced and eventually abandoned.

field development planning

The work of choosing well count, facilities and phasing to maximize value from a discovery.

field device

A physical input or output device connected to a PLC system, controller, or variable speed drive that provides information or receives signals required to regulate operation.

field effect transistor (FET)

A special class of transistor in which current flow is controlled by the effect of the voltage potential applied to the gate with respect to the source.

field offshore

A producing field located at sea rather than on land.

field print

A field print is an initial analog well log printout, or playback, of well log data versus depth in the well made at the wellsite.

field separation

Separating gas, oil and water at the wellsite rather than at a central plant.

field shoe

A slider placed between the rotor and a steel plate during the disassembly of an AC generator; the rotor slides on it as the rotor is pulled out of the stator.

field static

The static correction derived from field measurements of the weathered layer.

field tape

The recording medium carrying seismic data as acquired in the field, before any processing.

field termination

Where field wiring lands in a junction box or cabinet.

field weld

A weld made on location as the line is laid, joining pipe joints end to end.

field winding

The winding producing a machine's magnetic field.

field wiring

Wiring performed in the field to connect field devices to a PLC system.

fieldbus

A decentralized network that connects input and output smart field devices, controllers, and operator interfaces, in which control decisions can be placed in the field devices for more immediate and accurate control of industrial processes. Also called an I/O bus.

fill cement

A cement system used to isolate non-productive intervals above the zones of interest, where high strength is not required.

fill line

A pipe that is used to admit material into a tank.

fill sub

A ported sub that lets the string fill as it is run, so it does not have to be filled from surface.

fill valve

The valve admitting liquid to fill a vessel.

filler rod

Additional metal used to fill in the seam between two base metals in welding applications. Also called consumable rod.

film lubricant

The lubricant film separating two loaded surfaces.

film lubrication

Lubrication in which a full fluid film separates the surfaces.

film-forming amine

A cationic amine that adsorbs onto steel to leave a persistent protective film, used as a corrosion inhibitor.

filter

In electronics, a circuit that conditions an input signal to remove unwanted frequencies or enhance a specific frequency range. In processing, a separation device that uses a filter medium to remove solids from a liquid. In HVAC, an air cleaning device to prevent contaminants from entering conditioned areas.

filter cake

The solid residue deposited on a permeable formation (e.g., a borehole wall) when a slurry such as drilling mud is forced against it under pressure. The liquid that passes through the formation leaving the cake behind is called filtrate.

filter cake, mud cake

The residue deposited on the borehole wall when a drilling fluid is forced against it under pressure. Also termed mud cake.

filter cell

The pressurized cell of a filter press, holding the mud sample against a filter medium while filtrate is collected.

filter circuit

A circuit that smooths out a pulsating DC voltage. Also, a device in protective relaying that allows only a small amount of fault current to flow through a differential relay voltage coil.

filter loss

The volume of filtrate collected in 30 minutes under the standard API static filtration test.

filter media

The permeable materials in a filter through which liquid passes while solids are retained.

filter medium

The permeable material in a filter that does the separating, retaining solids on its surface or within itself.

filter press

The pressurized apparatus used to measure a drilling fluid's filtration behavior, static or stirred.

filter-cake quality

How thin, tough and impermeable the cake a mud deposits is — the properties that decide whether it protects the hole or sticks the pipe.

filter-cake thickness

The thickness of the cake left on the filter paper after the standard filtration test, reported in 32nds of an inch.

filtered brine

Completion brine passed through filters to remove particles that would otherwise plug the formation.

filtering

Hectically reducing a circuit's response to high frequencies or sudden changes.

filters

Devices used to separate solid impurities from process fluids.

filtrate

The liquid part of a slurry that passes through a rock formation, leaving the filter cake on the formation rock.

filtrate loss

The volume of liquid a drilling fluid loses into the formation.

filtrate slump

The gravity-driven downward movement of mud filtrate through the invaded zone in the time between drilling and logging.

filtrate tracer

A chemical or isotope added uniformly to a fluid so its filtrate can later be recognized and quantified in cores or samples.

filtrate volume

The volume of filtrate collected in 30 minutes in the standard API static filtration test.

filtration

The separation of solids from a slurry by passing the liquid through a medium that retains the solids as a cake.

filtration test cell

The pressurized, heated cell in which a mud's filtration behavior is measured against a filter medium.

filtration tester

Apparatus that measures a fluid's filtration behavior with the fluid circulating rather than at rest.

fin-fan condenser

A condenser that uses air to cool vapours.

final assessment results (FAR)

The Assessment scores after completion of the full assessment process.

final boiling point (FBP)

The temperature at which all of a fraction is vaporized; also called the end point.

final control element

The output field device that directly affects the manipulated variable.

final feedwater outlet temperature

The temperature of the feedwater coming out of the highest pressure feedwater heater on its way to the economizer.

final flow period

The last flowing sequence of a drillstem test, run long enough to establish stable conditions before the final shut-in.

final flow rate

The stabilized rate immediately before shut-in, used as the reference rate in analyzing the buildup.

final flowing pressure

The pressure at the formation face at the instant the well is shut in for the final buildup.

final inspection and test

The third step in a production process, which ensures that the final product meets the customer's requirements.

final investment decision (FID)

The board approval that commits the capital and starts construction.

final operating temperature

The sum of the internal heat produced when current flows through a conductor plus the amount of heat in the conductor before current starts to flow through it.

final separation

The last separation stage before product goes to storage or sale.

final shut-in period

The last buildup sequence of a drillstem test, following the final flow period.

financial acumen

Reading financial statements well enough to see what a decision will do to them.

financial audit

Review of the measurement and ticketing records behind a sale, as distinct from checking the meter itself.

financial close

The point at which all financing documents are signed and funds can be drawn.

financial crime

Fraud, money laundering and related offenses the financial system is required to detect.

financial institution

Any entity providing financial services, from banks to insurers to funds.

financial markets

The markets in which capital, debt, currency and derivatives are traded.

financial modelling

Building the spreadsheet that turns technical and fiscal assumptions into cash flow and returns.

financial ratio analysis

Reading relationships between accounting figures to judge performance, leverage and liquidity.

financial statement

A formal report of an entity's financial position or performance.

fine

In the strict API sense, a particle in the 44 to 74 micron size range.

fine particle

A small solid particle, which penetrates further into both filters and lungs.

fine print notes (FPN)

Explanatory material included in the NEC in smaller than normal type (fine print).

fine-grained sediment

Sediment of silt and clay size, which becomes seal or source rather than reservoir.

fines

Very small particles ranging in size from 44 to 74 microns, including small broken particles of catalyst.

fines migration

The movement of clay or fine quartz particles through the pore system under production drag forces, until they bridge and plug pore throats.

fingerboard

The rack on the derrick's monkeyboard in which stands of pipe are held upright during a trip.

fingering

The uneven advance of a displacing fluid, which pushes narrow tongues through the reservoir and bypasses the oil between them.

fining-upward

Grain size decreasing upward through a bed, the signature of a waning current.

finished products

Products that leave a refinery.

finite difference

Solving a differential equation by approximating derivatives on a grid, the usual reservoir simulation method.

finite-conductivity fracture

A hydraulic fracture along which pressure drops appreciably during production, because its conductivity is not effectively infinite.

finite-wellbore solution

The diffusion equation solved with the well treated as a cylinder of real radius rather than as a line source.

fire brigade

A group of workers in a facility with the responsibility for fighting fires.

fire diamond

A labelling system that uses color-coded sections to rate the flammability, reactivity, and health risks of a hazardous chemical and indicates special hazards. Officially called a National Fire Protection Association (NFPA) 704 label.

fire extinguisher

A portable device used to put out fires.

fire extinguishing equipment

The provided means of first-response firefighting, whose type must match the fuel present.

fire hazard

A condition able to start or feed a fire.

fire hose

Hose delivering water or foam to a fire.

fire monitor

A permanently mounted piece of fire fighting equipment that has a nozzle, but not a hose.

fire tube

A tube in a fire tube boiler through which combustion gases are routed.

fire tube boiler

A type of boiler in which tubes are used to route hot gases created by combustion through a water-filled shell.

fire watch

Personnel assigned to watch for a fire during an oxy-fuel gas welding job and be prepared to extinguish it.

firebox

The chamber in which fuel burns in a fired heater or boiler.

fired reboiler

A type of furnace that acts as a reboiler, using burning fuel as the heating medium.

firefighting

The activity of extinguishing fire.

fireflooding

In-situ combustion in which a fire is ignited at the sandface of an injection well and driven through the reservoir by injected air.

fireman

A control valve that regulates fuel flow to furnace burners.

firewall

A control filtering traffic between networks according to policy.

firing head

The device that initiates a perforating gun conveyed on tubing, drillpipe, coiled tubing or slickline.

firing level

The level of water that must be contained in a steam drum before startup of a boiler.

firing rate

The amount of fuel burned and the amount of steam generated by a boiler. Also called boiler demand.

firm pipeline

Pipeline capacity contracted so it cannot be curtailed.

first 30 days

The initial period in a role, where impressions form and priorities are set.

first arrival

The earliest energy to reach a receiver from a source, whatever path it took.

first break

The first arrival of energy on a seismic trace, picked as the onset rather than the peak.

first breaks

First breaks are the first signals that are recorded by the receivers.

first offer

The initial proposal, whose framing exerts more influence than most negotiators expect.

first reading

The shallowest depth at which a log curve gives a reliable value.

first tranche

Similar to a royalty, this is the initial payment made under a Production Sharing Contract (PSC). Unlike a royalty, it is typically distributed between the Government and the Operator according to their respective shares of Profit Oil.

first-contact miscibility

The condition in which two fluids mix in all proportions on first contact, forming a single phase without needing mass transfer between them.

fish

Any unwanted object left in a wellbore—such as junk metal, hand tools, drill pipe, drill collars, or an MWD package—which normally must be removed or bypassed before well operations can continue.

fish eye

A lump of partly hydrated polymer that forms when dry product is added faster than it can disperse.

fish tape

A very stiff steel. wire that has a hook on the end and can be pushed through conduit without bending or collapsing.

fish, fishing

A fish is any object in a borehole which normally needs to be removed by fishing before well operations can continue. It can be junk, part of the drill string, a tool or any other equipment preventing ongoing well activities.

fishbone wells

A horizontal well with short laterals branching off its main bore at intervals, like ribs from a spine.

fishing

The application of tools, equipment, and techniques for the removal of junk, debris, or fish from a wellbore. Key elements include understanding the dimensions and nature of the fish, wellbore conditions, tools and techniques employed, and the process for handling the recovered fish at surface.

fishing bell

A tapered guide run on the bottom of a fishing string to funnel the top of the fish into the tool.

fishing diagram

A dimensioned sketch of everything in the hole, showing each tool's outside diameter, bore and fishing neck profile.

fishing neck

The machined external profile at the top of a tool on which a fishing tool latches if the string has to be recovered.

fishing tool

Any of the specialized tools used to grab, latch, break up or otherwise engage something lost or stuck in the well.

fishtail

An early drag bit design, and the shape of a worn cutting structure.

fissility

Fissility refers to the tendency of a rock to split into thin, parallel layers or laminae along bedding planes--particularly fine-grained sedimentary rocks like shales. This property results from the alignment of clay minerals and other platy minerals within the rock fabric, which is often the result of compaction and diagenesis. Fissility can be influenced by factors such as the depositional environment, sediment composition, and burial history.

fitness for release

Whether an increment meets the standard required to go live.

fitted variogram

An experimental variogram to which a permissible mathematical model has been fitted, giving nugget, sill and range.

fitting

Any connecting component in a fluid line — elbow, tee, nipple, union or flange.

five basic approaches to negotiation

The main postures a negotiator can adopt, from competitive to collaborative.

five stages of the career life cycle

The course's division of a career from entry through establishment, mid-career, late career and exit.

five stages of the interview process

The course's sequence from screening through to offer.

five stages of the negotiation process

The course's sequence from preparation through opening, bargaining, closing and implementation.

five steps of problem solving

Define, analyze, generate options, select and implement, then review.

five styles of conflict management

Competing, collaborating, compromising, avoiding and accommodating.

five-spot

A flood pattern with four injectors at the corners of a square and one producer at its center.

five-step coaching process

IHRDC's sequence for a coaching conversation from opening through to agreed action.

five-step stage-gate process

IHRDC's rendering of the stage-gate model as applied to exploration and production projects.

fixed allowable

A fixed allowable rate is a production rate designated by a government regulatory agency.

fixed and overtime costs

Costs unaffected by duration against premium rates for hours beyond standard.

fixed bed sweetening system

A type of mercaptan conversion system in which the catalyst is deposited on a bed material.

fixed choke

A choke with an orifice of unchangeable size, which sets flow by geometry rather than by adjustment.

fixed refrigerant cycle heat pump

A refrigeration system in which air temperature is controlled by the direction of air flow.

fixed source method

A survey geometry in which the source stays in one place while receivers are moved.

fixed speed coupling

A coupling transmitting rotation at a single speed ratio.

fixed vs. variable costs

Costs that do not change with output against those that do.

fixed-bed carbon adsorber

A device that collects gas stream contaminants on a bed of activated carbon.

fixed-cutter bit

A bit whose cutting elements are set into the body and do not rotate independently, cutting by shear rather than by crushing.

fixture joint

A type of splice that is used for splicing a wire to a branch circuit, such as what might be done for a lighting fixture.

FK filter

An FK filter is a seismic processing filter that minimizes surface waves and coherent energy but strengthens the reflected waves.

flag joint

A short or otherwise distinctive joint placed at a known point in a string, so its passing can be detected as a depth reference.

flake LCM

Thin flat lost circulation material — mica, cellophane or shredded plastic — that lies across the formation face to seal it.

flake lost-circulation material

Flat, plate-like material added to mud to bridge and seal a loss zone by lying flat across it.

flame arrester

A device that helps prevent fires and explosions inside a storage tank by interrupting or preventing the passage of a flame.

flame arrestor

Element with passages too narrow to let a flame propagate, fitted where a vent could ignite.

flame ionization detector

A flame ionization detector (FID) is a scientific instrument that measures analytes in a gas stream.

flame screen

A safety feature used to prevent fires on a barge.

flameout

The unexpected loss of a burner flame during furnace operation, creating potentially explosive conditions.

flammability

How readily a substance ignites and sustains flame.

flammability hazard

A material that poses a risk of detonating and/or burning.

flammability range

The fuel-in-air band that will ignite, and for hydrogen it is unusually wide at 4 to 75 percent.

flammable

A chemical that falls into one of the following categories: •"Aerosol, flammable" means an aerosol that, when tested by the method described in 16 CFR 1500.45, yields a flame projection exceeding 18 inches at full valve opening, or a flashback (a flame extending back to the valve) at any degree of valve opening; •"Gas, flammable" means: •A gas that, at ambient temperature and pressure, forms a flammable mixture with air at a concentration of 13 percent by volume or less; or •A gas that, at ambient temperature and pressure, forms a range of flammable mixtures with air wider than 12 percent by volume, regardless of the lower limit. •"Liquid, flammable" means any liquid having a flashpoint below 100 deg. F (37.8 deg. C), except any mixture having components with flashpoints of 100 deg. C or higher, the total of which make up 99 percent or more of the total volume of the mixture. •"Solid, flammable" means a solid, other than a blasting agent or explosive as defined in 1910.109(a), that is liable to cause fire through friction, absorption of moisture, spontaneous chemical change, or retained heat from manufacturing or processing, or which can be ignited readily and when ignited burns so vigorously and persistently as to create a serious hazard. A chemical shall be considered to be a flammable solid if, when tested by the method described in 16 CFR 1500.44, it ignites and burns with a self-sustained flame at a rate greater than one-tenth of an inch per second along its major axis.

flammable gas

Gas able to ignite in air.

flammable liquid

A liquid giving off vapor that will ignite at ordinary temperatures.

flammable material

A material that can be ignited easily and will burn quickly.

flammable vapor

Vapor able to ignite in air.

flammables

Chemicals that are capable of being easily ignited and of burning rapidly. The exact conditions for this classification differ for solids, liquids and gases.

flange

A rib or rim used to attach objects such as the two halves of a pump casing.

flange bolt

A bolt clamping a flanged joint.

flange union

A bolted flanged joint allowing a spool or meter to be removed without cutting pipe.

flange up

To bolt flanged components together into a completed pressure-containing assembly.

flanged

Joined by bolted rims, the standard pressure connection at surface.

flanged connection

A bolted pressure joint between pipe or equipment.

flapper

The hinged closure element in a subsurface safety valve.

flapper valve

A check valve with a hinged plate that swings open to allow flow one way and closes against flow the other.

flaps

Flaps are attached to pads to improve borehole contact.

flare

The controlled burning of gas that cannot be used or safely vented, and the stack on which it is burned.

flare gas

The vapor or gas routed to a flare for burning.

flare gas recovery

Capturing and compressing gas that would otherwise be flared.

flare system

The headers, knockout and stack that burn relieved gas safely rather than venting it.

flaring

The burning of natural gas for safety reasons or when there is no way to transport the gas to market or use the gas for other beneficial purposes (such as EOR or reservoir pressure maintenance). The practice of flaring is being steadily reduced as pipelines are completed and in response to environmental concerns.

flaser bedding

Flaser bedding is a sedimentary structure characterized by alternating rippled sand and discontinuous mud layers created by the deposition of mud on previously existing sand ripples.

flaser-bedded

Flaser bedding is a sedimentary structure characterized by alternating rippled sandstone and discontinuous mud layers created by the deposition of mud on previously existing sand ripples.

flash

When vapors rise suddenly from a liquid, typically the result of lowering pressure on a liquid with or without heat.

flash drum

A piece of equipment used to separate the light ends from crude before the crude enters an atmospheric tower.

flash mixer

A vessel mixing a dosed chemical rapidly into a stream.

flash point

The lowest temperature at which a liquid gives off enough vapors to form a flammable or ignitable mixture with air when exposed to a source of ignition.

flash zone

The section of a distillation tower near the feed point where part of the feed vaporizes (flashes) as it enters the tower.

flashback arrestor

A regulator safety device that stops fire.

flashover

The current effect created when the voltage differential across a bearing exceeds the resistance. Also, a short circuit between the brushes of a motor that occurs when air is hot enough to act as a conductor.

flashpoint

The minimum temperature at which a liquid gives off a vapor in sufficient concentration to ignite when tested as follows: (i) Tagliabue Closed Tester (See American National Standard Method of Test for Flash Point by Tag Closed Tester, Z11.24 - 1979 (ASTM D 56-79)) - for liquids with a viscosity of less than 45 Saybolt Universal Seconds (SUS) at 100 deg. F (37.8 deg. C), that do not contain suspended solids and do not have a tendency to form a surface film under test; or (ii) Pensky-Martens Closed Tester (See American National Standard Method of Test for Flashpoint by Pensky-Martens Closed Tester,Z11.7 - 1979 (ASTM D 93-79)) - for liquids with a viscosity equal to or greater than 45 SUS at 100 deg. F (37.8 deg. C ), or that contain suspended solids, or that have a tendency to form a surface film under test; or (iii) Setaflash Closed Tester (see American National Standard Method of test for Flash Point by Setaflash Closed Tester (ASTM D 3278-78)). Organic peroxides, which undergo autoaccelerating thermal decomposition, are excluded from any of the flashpoint determination methods specified above.

flat gels

Gel strengths that barely change between the ten-second and ten-minute readings.

flatten

To align seismic traces on a chosen horizon so structure at that level is removed.

flattened section

A seismic section redisplayed with a chosen horizon made flat, so structure below and above is shown relative to it.

flexible coupling

A coupling transmitting torque while tolerating small misalignment.

flexible diaphragm

A flexible membrane transmitting pressure while separating two fluids.

flexible member pump

A rotary pump that uses components such as flexible vanes or a flexible tube to move fluid.

flexible riser

An unbonded flexible pipe connecting a seabed system to a floating facility.

flexible work arrangement

Any variation from standard hours or location agreed with the employer.

flextime

Choosing start and finish times within agreed limits.

flexural

Relating to bending, as in the crustal flexure that forms foreland basins.

flexural mode

A borehole acoustic mode in which the borehole flexes from side to side, excited by a dipole transmitter and polarized in the plane of that source.

flexure

Bending of the lithosphere under load, which creates and shapes basins.

flinger

A collar that is attached to a pump shaft between the gland follower and the bearing housing to prevent fluid from entering the bearing housing.

flip-flops

Is an electronic circuit or a bistable multivibrator that has two stable states and thereby is capable of serving as one bit of memory. Usually a flip-flop includes zero, one, or two input signals; a clock signal and an output signal that often includes the complement as well as the normal output.

Flipped Classroom

Learners take in content beforehand so contact time is spent applying it.

FLNG

A floating liquefied natural gas facility: a vessel that produces, liquefies, stores and offloads LNG at the field, with no onshore liquefaction terminal.

float

An object that rides near the surface of a liquid and changes vertical position with any change in level.

float collar

A casing component set a joint or two above the shoe, carrying a check valve and providing a landing seat for the cementing plugs.

float column

The chamber housing a level float, isolated from turbulence in the vessel it measures.

float joint

The joint or joints of casing between the float shoe and the float collar, which stay full of cement after the plug bumps.

float shoe

A rounded, valve-equipped component on the bottom of the casing string that guides it into the hole and prevents backflow.

float switch

A pilot device operated by the level of a liquid.

floating piston

A piston in the sample cylinder which maintains sample integrity by separating the sample from the displacement fluid.

floating production, storage and offloading (FPSO)

Provides alternative to pipeline to store oil production and load vessels for movement to markets.

floating roof tank

An atmospheric tank with an internal or external roof that floats on the surface of the stored liquid, moving upward as liquid enters and downward as liquid is withdrawn.

floating storage

Holding cargo on a chartered tanker when onshore tanks are full or the forward price justifies waiting.

floc

Fluffy clumps formed during flocculation as the sticky masses from coagulation come in contact with suspended solids in water.

flocculant

A chemical that creates ions in water that cause suspended particles to clump together. Lime and ferric chloride are two types of flocculants.

flocculate

To gather charged particles such as clays into loose, open aggregates called flocs, raising viscosity and gel strength.

flocculated

Clumped into aggregates, which changes a fluid's viscosity and filtration.

flocculation

The second step of clarification, in which the sticky masses formed during coagulation are gently stirred to form fluffy clumps called floc.

flood front

The advancing interface between injected fluid and the reservoir fluid it displaces.

flooding

An abnormal condition in a distillation tower caused by the buildup of liquid on trays due to too much liquid flow down the column or too much vapor flow up the column, preventing proper liquid flow.

flooding pattern

The geometric arrangement of injection and production wells in a flood.

flooding surface

A surface showing an abrupt increase in water depth across it, separating shallower strata below from deeper above.

floor-fired furnace

A furnace that has burners installed in the floor of the shell.

floppy disk

A 3 1/2" disk widely used for storage or transfer of computer information; still called floppy, although the thin, flexible sheet of acetate on which data is stored is now encased in hard plastic.

flow after flow

A gas well deliverability test in which the well is flowed at a series of rates one after another, each held until the pressure stabilizes.

flow after flow tests

Deliverability tests, often required by regulation, in which successive flow rates are held until each reaches stabilized flow.

flow assurance

The discipline of keeping hydrocarbons flowing from reservoir to sales point without blockage or interruption.

flow back

Producing fluids back from a well after a treatment, to recover the treating fluid before normal production begins.

flow characteristic

How a well or system behaves as rate and pressure change.

flow check

A short period with the pumps off, watching the well to confirm it is not flowing.

flow coefficient, C v

The number of US gallons of water per minute a valve passes at a 1 psi pressure drop, abbreviated Cv.

flow concentrating

Said of a flowmeter that forces all the flow through its spinner using a basket or packer.

flow control valve

A valve modulating flow to hold a measured rate.

flow controller

The instrument holding flow rate.

flow coupling

A short, heavy-walled tubing component installed where turbulence is expected, so erosion attacks the coupling rather than the tubing.

flow cross

A pressure-containing body with four or more flanged or studded outlets, used to split and direct flow at the wellhead.

flow diagram

A symbolic representation of pieces of equipment, piping, and direction of flow, in a fluid (piping) system; also referred to as a process flow diagram.

flow efficiency

The ratio of a well's actual productivity index to the productivity index it would have with no damage or stimulation.

flow energy

Energy related to the pressures associated with fluid flow.

flow equation

The relation between rate and pressure drop for a given geometry and fluid.

flow indicator

The device showing flow rate locally.

flow line

The pipe carrying produced fluid from the wellhead to the first processing facility.

flow loop

A closed circuit of pipe used to study flow behavior and to calibrate instruments under controlled conditions.

flow measurement

Determining flow rate, which for gas is meaningless until stated at a reference pressure and temperature.

flow model

A computational representation of fluid movement through a reservoir, solved in two or three dimensions.

flow period

A part of a well test during which the well is flowing, run long enough for conditions to stabilize.

flow profile

A record of how much fluid enters or leaves the wellbore at each depth, from a production or injection log.

flow rate

The amount of fluid passing a particular point in a certain unit of time, often expressed in gallons per minute, cubic feet per day, barrels per day, etc.

flow regime

The geometry of flow around a well at a given time in a pressure transient test, recognized from the shape of the derivative curve.

flow reversal

A condition in which the areas of higher and lower pressure in a cat cracking unit are reversed.

flow simulation

The numerical modeling of fluid movement through a reservoir model over time, to forecast performance.

flow structure

The geometry of fluid movement through a volume, described by its principal flow directions.

flow switch

A pilot device operated by changes in the flow of a liquid or gas.

flow test

A flow test is an operation on a well designed to demonstrate the existence of moveable petroleum in a reservoir by establishing flow to the surface.

flow transmitter

The instrument converting a flow measurement into a transmitted signal.

flow unit

A flow unit is a mappable portion of the total reservoir within which geological and petrophysical properties that affect the flow of fluids are consistent and predictably different from the properties of other reservoir rock volumes.

flow velocity

How fast fluid moves, as distinct from how much moves.

flowage

The plastic movement of salt or shale under load.

flower structure

The upward-splaying array of faults branching from a strike-slip fault at depth, seen in section.

flowing bottomhole pressure

The pressure at the bottom of the hole while the well produces, which sets drawdown.

flowing gas

Gas actually in motion, whose pressure and temperature differ from static conditions.

flowing neutron log

A neutron log recorded with the well flowing, to locate the gas-liquid interface inside the borehole rather than in the formation.

flowing pressure

The pressure at the formation face while the well is producing.

flowing well

A well whose reservoir pressure is sufficient to lift fluid to surface at a commercial rate without artificial lift.

flowing wellhead

The wellhead of a well producing under its own pressure.

flowline manifold

The header assembly where several wells' flowlines are gathered and routed to the production or test separator.

flowline mud sample

Mud caught at the flowline before it reaches the shakers, representing what has just come out of the hole.

flowline sample

A sample taken at the flowline, before any surface treatment or solids removal.

flowmeter

A flowmeter is a device for measuring in-situ the velocity of fluid flow in a well completed for production or injection. The most common device is the spinner flowmeter.

flowstream sample

A sample taken from the flowing wellstream at the wellhead, before separation.

flue gas

The combustion product gas from burning hydrocarbons in air, largely nitrogen and carbon dioxide.

fluid

A substance that flows and yields to any force tending to change its shape. Both liquids and gases are fluids.

fluid caliper

A borehole volume determined by timing a tracer or marker between two points and combining it with the measured flow rate.

fluid catalytic

Catalytic cracking using a fluidized catalyst bed.

fluid catalytic cracking

Cracking heavy gasoil over a fluidized catalyst to make gasoline, the workhorse conversion unit.

fluid catalytic cracking unit

See Cat cracker.

fluid compatibility test

A laboratory check that two fluids meeting downhole will not precipitate, emulsify or gel.

fluid compressibility

The fractional change in a fluid's volume per unit change in pressure applied to it.

fluid contact

Fluid contact is the interface that separates fluids of different densities in a reservoir. Horizontal contacts are usually assumed, although tilted contacts occur in some reservoirs.

fluid density

Fluid density is the density of the fluids enclosed in the pore spaces.

fluid displacement

A method of sampling in which the sampled product replaces a fluid in the sample cylinder.

fluid efficiency

The ratio of stored volume within the fracture to the total fluid injected.

fluid flow

The movement of a liquid or a gas from one point to another.

fluid interface log

A flow profile obtained by pumping two different fluids and logging the interface between them as it moves.

fluid invasion

Fluid invasion is a general term to describe the presence of a particular fluid in an undesirable area, such as the movement of drilling mud into a section of the reservoir formation.

fluid leakoff

Loss of fracturing fluid into the formation, which limits fracture growth.

fluid level

The static depth of fluid in a well that cannot flow naturally, measured from surface.

fluid loss

The leakage of the liquid phase of a mud, slurry or treatment fluid into the formation, leaving its solids behind as filter cake.

fluid pound

The shock felt when a sucker-rod pump's plunger strikes the liquid surface in a partly filled barrel, because the pump is outrunning the inflow.

fluid saturation

The measure of the fluid volume present in the pore volume of a porous medium, such as a hydrocarbon reservoir. The saturation of any particular fluid is the ratio of that fluid volume to the total pore volume of the rock.

fluid tester

A wireline tool that seals against the borehole wall to measure formation pressure and draw fluid samples.

fluid thermometer

A temperature measurement device that works on the principle that most fluids expand when they are heated and contract when they are cooled.

fluid velocity

The speed at which fluid moves through pipe or pore, which governs erosion and lifting.

fluid viscosity

A fluid's resistance to shear, which for oil governs how readily it flows to the well.

fluid-density log

A production log of the density of the fluid in the wellbore against depth.

fluid-friction reducer

A polymer added at low concentration to cut turbulent friction pressure in the tubing.

fluid-loss additive

An additive that reduces the volume of filtrate a fluid loses to the formation.

fluid-loss control

The management of how much filtrate a mud, slurry or treatment fluid loses into the formation.

fluid-loss-control material

An additive that reduces the volume of filtrate a fluid loses to the formation, usually by building a tighter cake.

flume flow measuring device

An open channel flow measuring device that uses a downward sloping throat as a restriction. The liquid level behind the restriction is converted to a flow rate.

fluoboric acid

An acid system that hydrolyses slowly to release hydrofluoric acid deep in the formation, replacing HF as it is consumed.

fluorescence

The emission of light by a substance that has absorbed light or other electromagnetic radiation. Under ultraviolet radiation, all crude oils exhibit fluorescence which varies in intensity and hue.

fluorine

The most reactive halogen, and the basis of the fluoropolymers used for seals.

fluoroscopy

Real-time X-ray imaging of a core against a fluorescent screen, rather than onto film.

flush joint

A connection whose outside or inside diameter matches the pipe body, leaving no upset at the coupling.

flush production

The high initial rate a new well delivers before pressure and any fracture contribution decline.

flush valves

Valves that are opened to direct water down the sides of a bottom ash hopper so that ash clinging to the sides of the hopper is rinsed away.

flushed

, or The flushed zone is the volume of rock close to the borehole wall in which all of the moveable fluids have been displaced by mud filtrate.

flushed zone

The volume of rock close to the borehole wall in which all of the moveable fluids have been displaced by mud filtrate.

flushed zone, invaded zone

The flushed zone is the volume of rock close to the borehole wall in which all of the moveable fluids have been displaced by mud filtrate.

flushed, or invaded, zone

The volume of rock close to the borehole wall in which some or all of the moveable fluids have been displaced by mud filtrate. It consists of the flushed zone (where all moveable fluids are displaced) and the transition zone.

flushed-zone water saturation

The fraction of the flushed zone's pore space occupied by water, mostly mud filtrate, symbol Sxo.

fluvial

Pertaining to rivers and running water — their environments, processes and deposits.

fluvial deposits

Sediments deposited by rivers, streams, and associated gravity flow processes, formed by uni-directional fluid movements.

flux

In electrical work, a cleaning agent used to remove oxidation during soldering. In magnetism, a measure of the strength of a magnetic field over a given area.

flux density

The magnetic field strength in the core, typically measured in Telsa or Gauss.

flux gate compass

The basic fluxgate compass is a simple electromagnetic device that employs two, or more, small coils of wire around a core of highly permeable magnetic material, to directly sense the direction of the horizontal component of the Earth's magnetic field.

flux leakage

The distortion of magnetic flux where a flaw interrupts the otherwise parallel flux lines induced in a steel wall.

flux line

A line representing the direction of magnetic field.

flux vector

A motor control method computing the rotor flux to control torque directly.

flux vector controller

An advanced type of inverter controller that can control both torque and speed by monitoring the internal characteristics of a motor during operation.

flux vector drive

A drive computing rotor flux to control motor torque directly, giving full torque at low speed.

fluxgate compass

An electromagnetic device that employs two or more small coils of wire around a highly permeable magnetic material.

fluxgate magnetometer

Fluxgate magnetometers deliver magnetic field measurements by periodically saturating a piece of ferromagnetic core material to modulate the local magnetic field and sensing this modulated magnetic field using a coil of wire.

fly ash

A fine, powdery substance that is left over after combustion and exits the boiler with the flue gas.

FOA

A designation for a forced-oil/forced-air-cooled power transformer; abbreviation for "forced oil to air."

foam breaker

An additive that lowers the surface tension of the bubble film so entrained gas can escape from a fluid.

foam buildup

Foam accumulating in a vessel, which reduces working volume and carries liquid over.

foam diversion

Using foam to block the zones taking fluid, so the next stage of a treatment goes elsewhere.

foam drilling

Drilling with a gas-liquid foam, giving low density where formation pressure is low.

foam flooding

An enhanced recovery process injecting foam to reduce the mobility of a driving gas and improve its sweep.

foam generator

A device in the surface line that mixes liquid foamer thoroughly into a gas stream to produce stable foam.

foam system

A type of fire protection system that uses foam to blanket a fire and extinguish it by removing its source of oxygen.

foamed

Made with entrained gas to reduce density, used for cement and for drilling fluid.

foamed cement

An ultralight cement made by injecting nitrogen into a base slurry with surfactants, giving very low density that still builds compressive strength.

foaming

A condition that can occur when contaminants get into feed or other streams entering a distillation column.

foaming agent

A surfactant added to generate and stabilize foam, whether as a drilling fluid or in a foamed cement.

foaming tendency

How readily a liquid foams, which limits column throughput long before flooding would.

foamy oil

Heavy oil produced under solution gas drive that reaches surface as an oil-continuous foam, with gas bubbles still dispersed through it.

FOB (Free On Board)

Seller's responsibility ends once the cargo is loaded; the buyer arranges and pays for the voyage.

fold

In geology, a structure generated when initially planar layers of rock formation become bent. In seismics, a measure of the redundancy of common midpoints, equal to the number of offset receivers that record a given data point and are added during stacking to produce a single trace.

fold stack

The number of traces summed at a point, which sets signal-to-noise in the stacked section.

follower magnet

A magnet, located inside a nonmagnetic enclosing tube, that follows the vertical movement of a doughnut-shaped float with a ring magnet inside its center hole. The follower magnet is attached to an indicator to provide continuous level measurement.

food to micro-organisms ratio

The relationship between the amount of organic materials, or food, that is supplied in an activated sludge system and the number of micro-organisms in the system.

footprint

An acquisition artifact imprinted on 3D seismic data by the geometry of the survey itself, appearing as a regular pattern unrelated to geology.

foraminifera

Single-celled marine organisms whose shells date and correlate strata.

force

A push or pull on an object. In ergonomics, the amount of physical effort required to perform a task. In PLC troubleshooting, a software tool that allows making a discrete input or output true or false regardless of field device or program logic demands.

force fed lubrication

A lubrication system in which lubricant is pumped (forced) to inlet ports of the prime mover, compressor frame, and cylinders to maintain a constant supply of lubricant to these areas.

force majeure

A clause excusing performance prevented by events outside a party's control.

force majeure situation

An event beyond a party's control that suspends its obligations while it lasts.

forced circulation

Circulation driven by a pump rather than by density difference.

forced convection

A type of convection heat transfer in which a mechanical device, such as pump or a fan, produces fluid movement.

forced draft fan

A type of fan used to blow or force air into a boiler or system.

forced draft furnace

furnace in which the energy required to move the air and combustion gases through the furnace is produced mechanically, by a fan.

forced-draft cooling tower

A mechanical-draft tower in which air is pushed through the tower by fans.

forced-oil/forced-air-cooled power transformer

A power transformer that is cooled. by the forced circulation of both oil and air.

forces for change

The pressures — competitive, regulatory, technological — that make change necessary.

forearc

The basin between a trench and its volcanic arc.

forearc basin

The basin between trench and arc, filled rapidly with immature sediment.

forecast statement

An opening that tells the audience what is coming, so they can follow the structure.

foreign content

The proportion of expatriate personnel, imported material and foreign services a contract permits, the complement of local content.

Foreign Corrupt Practices Act

The United States statute prohibiting bribery of foreign officials, with extraterritorial reach.

foreign currency exchange risk

Exposure to loss from movement in exchange rates between contract and settlement.

foreland

The basin formed on the stable side of a mountain belt as the crust flexes under its load.

foreland basin

The basin formed where the crust flexes under the load of an adjacent mountain belt.

foreset beds

A foreset bed is a sloping layer of sediment that is found at the end of a stream channel when a stream carrying sediment meets still water, causing the water's velocity to decrease and the sediment to be deposited. The angle of dip is determined by the depositional environment, including the speed and volume of the current, turbulence, and the amount of clastic material.

foreset, foreset beds

A foreset bed is one of the main parts of a river delta. It is the inclined part of a delta that is found at the end of the stream channel as the delta sediment is deposited along the arcuate delta front. As the sediments are deposited on a sloping surface the resulting bedding is not horizontal, but dips in the direction of current flow toward deeper water.

foresets

Foreset beds are inclined layers of sediment that form in the subaqueous delta front zone.

foreslope

The seaward-dipping flank of a reef or platform, where debris accumulates.

forklift

A powered truck lifting palletized loads on forks, and a common source of plant injuries.

formal authority

The right to direct that comes from position rather than from standing.

formal vs. informal feedback

Scheduled documented review against day-to-day comment, which does most of the work.

formate

A salt of formic acid, used in the oilfield to make dense, solids-free brines and as a low-damage completion fluid.

formation

A rock layer which has distinct characteristics (e.g. rock type, geologic age).

formation characteristic

A property of the formation relevant to drilling or completing it.

formation damage

Any reduction in near-wellbore permeability caused by drilling, completion or production, showing up as an extra pressure drop at the well.

formation dip

The tilt of the beds at the wellbore.

formation dip angle

Formation dip is the magnitude of the inclination of a formation bedding plane from the horizontal.

formation dip azimuth

Formation dip azimuth is the angle formed between geographic north and the direction of greatest slope on a bedding plane. Dip azimuth is conventionally measured clockwise from north, so that a plane dipping to east has a dip azimuth of 90°, and one to west 270°.

formation evaluation

The measurement and interpretation of formation properties to decide whether, where and how a well should be completed.

formation evaluation while drilling

Measuring formation properties with sensors in the bottomhole assembly as the hole is drilled, also called logging while drilling.

formation exposure time

The time between the bit penetrating a formation and the log being recorded across it.

formation factor

The ratio of the resistivity of a fully water-saturated rock to the resistivity of the water saturating it.

formation factor, formation resistivity factor

The formation resistivity factor is the ratio of the resistivity of the rock saturated with brine (Ro) to the resistivity of the brine (Rw).

formation fluid

Any fluid naturally present in the pore space of a rock — oil, gas or water.

formation fracture pressure

The pressure above which injected fluid will hydraulically fracture the rock rather than enter its pore space.

formation lithology

The rock type of the formation.

formation matrix, rock matrix

The formation, or rock, matrix or groundmass of a formation rock is the finer-grained mass of material in which larger grains, crystals, or clasts are embedded.

formation permeability

The rock's ability to transmit fluid, the property that decides whether a discovery is commercial.

formation porosity

The fraction of the rock that is pore space.

formation pressure

The pressure of fluids within the pores of a reservoir (also called pore pressure), usually hydrostatic pressure or the pressure exerted by a column of water from the formation's depth to sea level.

formation pressure gradient

Formation pressure gradient is the change in pressure per unit of vertical depth, typically in units of psi/ft, or kPa/m. Pressure increases predictably with depth in areas of normal pressure.

formation pressure, pore pressure

Formation pressure, or pore pressure, is the pressure of fluids within the pores of a reservoir, usually hydrostatic pressure, or the pressure exerted by a column of water from the formation's depth to sea level.

formation resistivity

The rock's resistance to electrical current, the primary indicator of hydrocarbon saturation.

formation tester

A tool taking pressure measurements and fluid samples at chosen depths.

formation water

The water that occurs naturally in the pore space of rocks.

formation water resistivity

The resistivity of the native water, a required input to saturation calculation.

formation water resistivity, Rw

The resistivity value of the water, uncontaminated by drilling mud, that saturates the porous formation. Formation water is also referred to as connate water or interstitial water.

formation water salinity

The dissolved salt content of the formation water.

formation, geological rock formation

Specific sedimentary strata, or other rock unit, in stratigraphic and petrologic studies.

formation, geological rock formation, geological formation

Specific sedimentary strata, or other rock unit, in stratigraphic and petrologic studies.

formic acid

The simplest organic acid, used to stimulate high-temperature wells where hydrochloric acid cannot be adequately inhibited.

forming, storming, norming, performing

Those four stages: coming together, conflict, settling on norms, and productive work.

formula

A statement that two specific mathematical expressions are equal; an algebraic equation for a typical problem or situation.

forthwith

Immediately, or as soon as circumstances reasonably allow.

forward bias

The bias potential that allows current flow across a P-N junction: a negative potential applied to the N-type material and a positive potential applied to the P-type material.

forward breakover

Switching into conduction in the forward direction.

forward breakover voltage

The value of anode-to-cathode voltage required to overcome the reverse-biased junction of an SCR and trigger it from the off state to the on state.

forward contract

A bilateral contract for future delivery, negotiated rather than exchange-standardized.

forward curve

The set of prices for successive future delivery months.

forward curved fan

A type of centrifugal fan in which the blades are inclined forward; also called a squirrel cage fan.

forward modeling

Forward modeling is the use of a model in order to simulate an outcome. The problem of getting the model to produce data from the input is called the forward problem. The forward model takes certain parameters and produces data that can then be compared with the actual observations.

forward multiple-contact test

A laboratory test contacting a gas sample repeatedly with fresh oil, tracing the vaporizing path toward miscibility.

forward problem

Computing what would be observed from a known model — the opposite of inversion, which infers the model from observations.

forward resistance

Resistance across a forward-biased P-N junction.

forward stroke

Movement of the compressor piston away from the drive unit.

fossil

A fossil is the preserved remains or traces of animals, plants, and other organisms.

fossil fuel

A fuel source (such as oil, condensate, natural gas, natural gas liquids or coal) formed in the earth from plant or animal remains.

fouling

The buildup of deposits on the internal surfaces pf a heat exchanger.

Foundation Fieldbus

The protocol intended to serve as a standard on I/O buses, especially suited to process industries.

foundation grant

Funding awarded by a grant-making body against an application.

foundation model

A large model pre-trained on broad data and then adapted to particular tasks rather than trained for each one.

four basic financial statements

Income statement, balance sheet, cash flow statement and equity statement, read together.

four steps of purposeful communication

The course's structure for planning a message before delivering it.

four-component (4C) seismic data

Seabed data recorded with three orthogonal geophones plus a hydrophone at each station, abbreviated 4C.

four-cycle engine

Engines that perform intake, compression, power, and exhaust in four strokes of the piston providing two revolutions of the crankshaft.

four-dimensional (4D) seismic data

Repeated 3D surveys over the same field, differenced to show how the reservoir has changed with production.

four-way valve

A multiport valve with four ports that directs flow in different combinations for two inlets and two outlets.

Fourier analysis

Decomposing a signal in time or space into a sum of sinusoids, each with its own frequency, amplitude and phase.

Fourier synthesis

Rebuilding a signal from the sinusoidal components found by Fourier analysis — the inverse of that decomposition.

Fourier transform

The mathematical pair that converts a signal between the time and frequency domains — analysis one way, synthesis back — used throughout seismic processing.

Fourier transform infrared spectroscopy

Measuring a rock sample's absorption of mid-infrared radiation to obtain a quantitative analysis of the minerals it contains.

FPSO

Floating production, storage and offloading vessel: a ship-shaped facility that processes produced fluids, stores the oil and offloads it to shuttle tankers.

frac

Shorthand for a hydraulic fracture treatment or the equipment used for it.

frac balls

Balls dropped or pumped to seat in a ball-activated sleeve, isolating the stage below and diverting the treatment to the next one.

frac crew

The combined personnel who execute a fracturing treatment — pump operators, blender and chemical hands, data engineer and supervisor.

frac fluid

The fluid injected to create and propagate a hydraulic fracture and to carry proppant into it.

frac gel

The viscosified fluid that carries proppant into the fracture, usually a crosslinked or linear guar derivative.

frac gradient

The pressure per unit depth at which a formation breaks down and takes fluid.

frac gun

A perforating gun loaded with charges that make a large, round casing hole rather than deep penetration.

frac head

The flow cross bolted on top of the frac tree, where the treating iron connects and the treatment enters the well.

frac iron

The temporary high-pressure surface pipe, valves and manifolds that carry a fracturing treatment to the well.

frac job

A hydraulic fracturing treatment, in which fluid is pumped above fracture pressure to create a conductive path into the reservoir.

frac manifold

The valve assembly that routes slurry from the missile to whichever well on the pad is being treated.

frac plug

A plug set to isolate one fracture stage from the next.

frac pump

A high-pressure positive displacement pump truck, the unit that supplies fracturing rate and pressure.

frac stack

The temporary high-pressure valve assembly installed above the wellhead for the duration of the fracturing treatment.

frac tree

The valve assembly installed for the duration of a fracturing treatment, in place of or above the production tree.

frac valve

A high-pressure isolation valve set on the wellhead below the frac equipment, the barrier between the well and the treating iron.

frac, hydraulic frac

Hydraulic fracturing, or fracking, is a drilling method used to extract oil or natural gas from the subsurface. In the fracking process, cracks in the subsurface formations are opened and widened by injecting water, chemicals, and sand at high pressure.

fraccing

Fraccing is the process of creating cracks in underground reservoir rock formations to increase the flow and recovery of hydrocarbons out of a well. This is done by pumping fluid containing proppants under pressure into the reservoir to prop open small cracks and openings that allow more hydrocarbons to be released.

fracking

Fracking is the process of creating cracks in underground reservoir rock formations to increase the flow and recovery of hydrocarbons out of a well. This is done by pumping fluid containing proppants under pressure into the reservoir to prop open small cracks and openings that allow more hydrocarbons to be released.

fractal

A geometry whose pattern repeats statistically across a range of scales, so that a small part resembles the whole.

fractal analysis

Analysis that treats a system as self-similar across scales, described by a fractal dimension rather than a characteristic length.

fractal networks

Fracture networks generated with fractal geometry, so that fracture density and connectivity are scale-invariant.

fractional flow

The share of total flow carried by one phase at a given saturation.

fractionation

The process of separating two or more hydrocarbon components in a stream by distillation, used to obtain valuable products and feedstocks from cracked gas, natural gas liquids, or alkylation products.

fractionation column

The tower separating natural gas liquids into individual products.

fractionation plant

The facility splitting mixed natural gas liquids into ethane, propane, butane and gasoline.

fractionation section

The section of an alkylation unit in which the unreacted fractions are separated from the product.

fractionator

A distillation column separating a feed into several cuts.

fractions

Different groups of hydrocarbons that are separated in a refinery's crude unit or other distillation processes.

fracture

A crack or surface of breakage within a rock, along which there has been no movement.

fracture acidizing

Injecting acid above fracture pressure so that it both opens a fracture and etches its faces unevenly, leaving a conductive path after closure.

fracture conductivity

The product of a propped fracture's in-situ permeability and its width — how much flow the fracture can actually carry.

fracture gradient

Fracture gradient is the pressure required to induce fractures in rock at a given depth.

fracture half-length

The distance from the wellbore to the tip of one wing of a hydraulic fracture.

fracture height

The vertical extent of a fracture, and what determines whether it stays in zone.

fracture length

The distance a fracture extends from the wellbore, and the main lever on stimulated productivity.

fracture network

The connected set of fractures through which a fractured reservoir actually flows.

fracture networks

Sets of intersecting fractures whose connectivity, rather than any single fracture, controls flow.

fracture orientation

The direction a fracture takes, set by the in-situ stress rather than by the well.

fracture permeability

The part of a dual-porosity reservoir's permeability carried by open natural fractures rather than by the matrix.

fracture plane

The surface a fracture occupies.

fracture porosity

Fracture porosity is the porosity contained in subsurface fractures.

fracture pressure

The pressure at which the formation parts, the upper limit on mud weight and injection.

fracture propagation

The growth of a fracture through rock as pumping continues.

fracture set

A group of fractures sharing orientation, formed in one stress regime.

fracture stimulation

Creating fractures to improve inflow where the rock will not produce unaided.

fracture system

The connected network of fractures in a rock volume.

fracture treatment

The stimulation job creating a propped fracture.

fracture width

The aperture of a fracture, which with length and height sets its conductivity.

fracture zone

A band of concentrated fracturing, which can be either the best flow path or the worst thief zone.

fracture, fractured

A fracture is crack or surface of breakage within a rock, along which there has been no movement.

fractured reservoir

Reservoir whose flow is controlled by fractures rather than by matrix pore space.

fractured-well analysis

Well test interpretation for a well intersecting a natural or induced fracture, using flow regimes that do not appear in an unfractured well.

fracturing

Pumping fluid above the rock's breaking pressure to create flow paths into the wellbore.

fracturing fluid

The fluid pumped to create a hydraulic fracture and transport proppant into it.

fracturing mandrel

A sleeve landed in the wellhead with a flanged top, onto which the frac tree is mounted.

fracturing manifold

The high-pressure valve assembly distributing treatment fluid from the pumps to the wells being treated.

fracturing operation

Pumping fluid and proppant to crack the formation and create flow paths to the well.

fracturing pressure

The pressure at which injected fluid opens and extends a fracture in the formation.

fracturing site

The wellsite location where a stimulation treatment is pumped.

fracturing sleeve

A sliding sleeve in a liner that is opened to expose one interval for fracturing, then left open or closed as required.

fracturing treatment

The pumped job that creates and props a hydraulic fracture.

frame

The part of an AC generator's stator that supports the stator core.

frame size

A method that is used to classify circuit brakes according to given current ranges.

frame/moveable coil

The parts in a moving-coil meter movement that move in response to the interaction between the fixed magnetic field and the field of the current-carrying, movable coil.

framework for agreement

An outline of the shape of a deal, settled before the detail is negotiated.

franchising

Licensing a proven business format to an operator who invests and runs it locally.

free air correction

The gravity correction for station elevation alone, adding 0.3086 mGal per meter of height above the datum.

free electron

An electron not bound to an atom, whose movement is electric current.

free fall distance

The distance that a body falls before a personal fall arrest system begins to apply force to stop the fall.

free fluid

Pore fluid that can move under normal reservoir conditions, as distinct from fluid bound by capillary or clay forces.

free fluid index

The free fluid index (FFInmr) is the NMR interpretation estimate of the producible porosity.

free gas

Hydrocarbon gas existing as a separate gaseous phase in the reservoir, rather than dissolved in oil or water.

free lift

The greatest distance that the forks can be raised without extending a forklift's mast.

free liquids

Liquids which can be removed in a two-phase separator.

free point

The deepest point at which a stuck string is still free to move, above which it can be recovered.

free radical

An active site in a molecule that has a highly reactive unpaired electron.

free water

Water that readily separates from other fluids; liquid water. In the dual water model, it refers to formation water that is not bound to clays.

free water level

The highest elevation at which the pressure of the hydrocarbon phase equals that of water, located at the base of the hydrocarbon column and the transition zone. It is equivalent to zero capillary pressure. Above this level, the reservoir may produce water alone, hydrocarbon and water, or hydrocarbon alone; below it lies the aquifer.

free water level (FWL)

The free water level is the highest point in the reservoir where the capillary pressure between water and oil is zero.

free-induction decay

The rapid decay of an NMR signal after excitation, caused by protons dephasing in an inhomogeneous field, abbreviated FID.

free-point indicator

A wireline tool that measures stretch and twist in the string to find the deepest point still free.

free-water knockout

A vessel that removes the water which separates readily from an oil stream, before the emulsion reaches heating or chemical treatment.

freezestat

A sensor used to provide feedback to the control system and initiate measures to reduce or prevent the intake of freezing air into a heating, ventilation, and air conditioning system.

freezing point

The temperature a liquid solidifies at.

freight rate

What it costs to move a cargo, expressed per tonne or as a Worldscale percentage.

frequency

The number of cycles completed per second, measured in hertz (cycles per second). Applies to AC power systems, sound waves, and other periodic signals. In electrical formulas, frequency is typically represented by a small f.

frequency domain

The representation of a signal as a function of frequency rather than of time.

frequency response

The range of frequencies within which an instrument or amplifier can respond and maintain constant gain. The higher the detectable frequency, the wider the bandwidth and the greater the frequency response.

fresh core

Core that has been preserved in the condition it reached surface in, before light components can escape or bitumen biodegrade.

fresh water

Water of low dissolved-solids content, and therefore low conductivity.

Fresnel zone

The Fresnel Zone, named after physicist Augustin-Jean Fresnel, is comprised of seismic waves that are reflected from a large, circular area of a reflecting surface. Arrival times in this zone differ by less than half a period from the first break and will interfere constructively, causing them to be detected as a single arrival.

friable

Crumbling easily, so the formation produces sand.

friction

The resistance to relative motion that exists between two surfaces or objects in contact with each other.

friction angle

The angle describing a rock's shear strength dependence on confining stress.

friction effect

The apparent density error a gradiomanometer shows in fast flow, because friction pressure loss is added to the hydrostatic difference it measures.

friction factor

The dimensionless number tying pressure loss to velocity, geometry and fluid.

friction lighter

A device that creates sparks by rubbing a piece of flint on a steel surface. Also called a striker or a spark lighter.

friction loss

Pressure lost overcoming friction in the flow path.

friction pressure

Pressure lost to friction along the flow path, which at high rate dominates the total.

friction pressure loss

Pressure consumed by friction along the flow path.

friction reducer

An additive that reduces friction — either the drag between tools and tubulars, or the turbulent friction pressure of a pumped fluid.

friction tape

A type of cotton cloth that has been treated with a sticky rubber compound. It is typically applied on top of another insulating material such as rubber tape.

frictional

Arising from friction, the principal source of pressure loss in flowing systems.

frictional pressure

The pressure required to overcome friction.

frictional pressure loss

Pressure consumed by friction, which rises with the square of velocity.

front and back office

The split between those who trade and those who confirm, settle and account for the trades.

front-end loading

Investing enough in early definition that scope is settled before capital is committed.

frontier acreage

Unproven acreage with little or no drilling history, carrying high geological risk.

frontier basin

A sedimentary basin with little exploration history and an unproven petroleum system.

Frontier Exploration Fund

The levy set aside under the Act to fund exploration in Nigeria's under-explored basins.

frontline manager

The first level of management, supervising people who do the work directly.

froth flow

A near-vertical multiphase regime of chaotic, aerated flow between slug and annular-mist, with gas and liquid intimately mixed.

FSRU (Floating Storage and Regasification Unit)

A moored vessel that receives, stores and regasifies LNG, avoiding an onshore terminal.

FT

Fourier transform — the operation converting a signal between the time and frequency domains.

FTIR

Fourier transform infrared spectroscopy: measuring how a sample absorbs mid-infrared radiation to obtain a quantitative mineral analysis of a rock.

FTIR spectroscopy

Fourier Transform Infrared spectroscopy. A form of infrared spectroscopy that uses complex mathematical equations to help smooth out peaks and provide rapid, accurate results.

fuel

A combustible material used to produce heat by burning.

fuel gas

Any gas that can be mixed with oxygen to fuel the extremely hot flame used in welding processes.

fuel gas scrubber

Scrubber cleaning gas taken for fuel, protecting engines and burners from liquid and solids.

fugitive emissions

Emissions of gases, vapors, or volatile organic compounds from pressurized equipment, including pipelines, due to leakage or unintended releases.

fulcrum

The point or support on which a lever pivots. On a forklift, the front wheel axle can act as a fulcrum if a load is too heavy.

full cost accounting

Capitalizing all exploration spending into a pool, including the failures.

full diameter

A core or sample analyzed at its whole diameter rather than as a small plug.

full diameter core

Core recovered at the full bit diameter, giving samples large enough to test bedding effects.

full diameter coring

In order to acquire a full diameter core, drilling must be halted. The drill string is removed from the wellbore, the drill bit removed and a rotary coring bit is attached in its place.

full diameter coring process

To acquire a full diameter core, drilling must be halted. The drill string is removed from the wellbore, the drill bit is removed, and a rotary coring bit is attached in its place.

full flow pressure

The pressure at which a valve is fully open and passing its maximum volume.

full line voltage

The supply voltage applied without reduction, as in a direct-on-line motor start.

full sonic waveform recording

The full sonic waveform recording consists of the entire waveform, including the compressional, shear and Stoneley waves used for interpretation applications.

full waveform

A recording in which the complete received signal is retained, rather than just a picked arrival time or amplitude.

full waveform acoustic logging tool, log

A full waveform acoustic logging tool is type of acoustic logging tool that uses a large number of receivers, typically 4 to 12. Such logging tools are designed to measure not only the compressional wave but also the shear and other acoustic waves generated by the transmitter. The separation and identification of these waves are facilitated by the use of an array of receivers placed about 6 in. [15 cm] apart, which is close enough to avoid aliasing but far enough to sample a significant moveout in the wave. The waveforms at each receiver are recorded and processed by signal processing techniques, such as slowness-time coherence, to measure the velocities of the different waves.

full-azimuth towed-streamer acquisition

Marine acquisition in which a single vessel tows its streamers in a circular or coil path so every azimuth is recorded.

full-face gasket

A type of gasket that covers the entire surface area of a flange and has holes to accommodate bolts/studs.

full-wave rectifier

A rectification device or circuit that conducts during both halves of an AC cycle, thus producing two DC output pulses during each AC cycle.

full-wave voltage doubler

A circuit that develops an output pulse during each half of an AC input cycle; the output is equal to twice the input voltage.

fullbore

Describing a tool or completion component whose internal diameter matches the tubing, leaving the passage unrestricted.

fullbore spinner

A flowmeter whose blades fold to pass through the tubing and spring open below it to sample the full casing cross section.

Fuller's earth

A type of clay used as an adsorbent to remove color and impurities from fats and oils.

fume hood

An enclosure drawing vapor away from the worker at a laboratory bench.

fumes

Solid particles generated by condensation from the gaseous state, generally after vaporization of molten metal.

function block

A component element or control device within a control loop that operates on input to produce a different output. In Fieldbus, a program feature that executes process control functions such as analog input/output or PID calculations, which may be placed in the most beneficial location on the fieldbus.

function control

A control on a test instrument that is used to determine the electrical property the instrument will measure and the unit of measurement that will be used.

functional specific competencies

Competencies that identify the daily activities that the individual is expected to undertake in their normal daily work activities and the knowledge and skills required to perform the job duties in a competent manner (competencies core to a disciple or function, such as, Finance, Operations, Maintenance, HR, Exploration, etc.).

funnel viscosity

A field measure of how thick a mud is: the seconds a quart takes to drain from a Marsh funnel. Comparative only, not a true viscosity.

furnace

A device used to heat raw materials in preparation for further processing.

furnace flame

The flame in a fired heater, watched because its shape reveals the air-fuel balance.

furnace oil

Fuel oil burned in a furnace.

fuse

A protective device containing an element that melts and opens a circuit when current flow exceeds a specific value for a given period of time. Unlike circuit breakers, fuses cannot be reset.

fuse block

The mounting carrying one or more fuses.

fuse holder

The fitting carrying and connecting a fuse.

fuse link

An alloy wire that melts when its current limit is exceeded.

future of work

The projected effect of technology and social change on how and where work is done.

future value

What a sum today will be worth later, once compounded.

future-state roadmap

The sequenced path from present arrangements to the intended ones.

futures contract

A standardized exchange-traded contract to buy or sell at a set price on a future date.

fuzzy logic

A form of artificial intelligence that enables a controller to continually "learn" from the way an actual process is working and use that information to self-tune for improved performance.

FWKO

Free water knockout — a vessel that removes free water from the wellstream before the oil goes on to be treated.

Fxy filtering

Fxy filtering is a spatial prediction filtering technique in the temporal frequency domain. The advantage of this filter is that it requires no prior knowledge of the dips of reflectors.