Oil and gas terminology · MLC-0103

Oil and gas terms: P (364)

• P rateAn abbreviation for penetration rate, which is the speed at which the drill bit advances through the rock...
• P waveA compressional wave, also known as a primary wave, that propagates through a medium by alternating...
• P&AAn abbreviation for plug and abandon, the process of permanently sealing a well that is no longer productive...
• PACPolyanionic cellulose, a water-soluble polymer used as a drilling fluid additive to control fluid loss and...
• Pack offTo seal or isolate an annular space in a wellbore using a packing element, often to prevent fluid movement or...
• PackerA downhole device that creates a seal between the tubing or casing and the wellbore wall. It isolates zones...
• Packer flowmeterA downhole tool that isolates a section of the wellbore using inflatable packers and then measures the flow...
• Packer fluidA specialized fluid placed in the annulus between the production tubing and the casing above a packer in a...
• PackingA deformable sealing material or set of components used to create a pressure-tight barrier around a moving or...
• Packing glandA component of a valve or pump that provides a seal around a moving stem or shaft to prevent fluid leakage...
• PackoffAn obstruction in the annulus of a wellbore caused by an accumulation of cuttings, cavings, or other debris...
• PadA prepared, level area of land constructed at the surface from which drilling and production operations are...
• Paddle blenderA mixing device equipped with rotating paddles or blades, used to blend and homogenize drilling fluid...
• Paddle mixerA mechanical device with rotating blades or paddles used to blend and agitate drilling fluid additives into...
• PAGAn abbreviation for polyalkylene glycol, a class of synthetic polymers used in water-based drilling fluids as...
• Paid-up leaseAn oil and gas lease where all delay rentals for the primary term are paid in advance at the time the lease...
• Pair productionThe creation of an electron and a positron from a high-energy photon interacting with the electromagnetic...
• PaleontologyThe study of fossils to determine the age and depositional environment of sedimentary rocks. By identifying...
• PaludalRelating to or formed in a marshy or swampy environment, characterized by shallow, stagnant water and...
• PalustrineDescribing a depositional environment related to marshes, swamps, or bogs, characterized by stagnant...
• PalynologyThe study of microscopic organic particles, such as pollen, spores, dinoflagellates, and other palynomorphs...
• PAOAn abbreviation for polyalphaolefin, a type of synthetic hydrocarbon used as a base oil in high-performance...
• ParaffinA waxy hydrocarbon compound, primarily composed of straight-chain alkanes, that can precipitate from crude...
• Paraffin controlThe management of paraffin wax deposition in oil production systems, which can restrict flow and reduce...
• Paraffin inhibitorA chemical additive used to prevent or reduce the deposition of paraffin wax in oil production and...
• Paraffin scraperA mechanical device run into a wellbore to remove paraffin wax deposits that accumulate on the inside of...
• Paraffin scratcherA scraping device mounted on a sucker rod string that removes paraffin wax from the inside wall of the...
• Paraffin-base crude oilA type of crude oil characterized by a high content of paraffin waxes, which are saturated hydrocarbons with...
• Paraffinic hydrocarbonAn organic compound consisting of only carbon and hydrogen atoms, with all carbon-carbon bonds being single...
• ParaformaldehydeA solid polymer of formaldehyde, used as a biocide in drilling fluids to inhibit bacterial growth. It slowly...
• Parallel foldA fold in which the thickness of each bed, measured perpendicular to the bedding surfaces, remains constant...
• Parallel resistivityThe electrical resistivity of a layered formation measured with current flowing parallel to the bedding, also...
• ParameterA measurable characteristic or property that defines a system, model, or process, often used as an input or...
• Parameters, see Parameter
• ParametricDescribing a method or model that relies on a finite set of parameters to characterize a system or data. In...
• ParasequenceA relatively conformable succession of genetically related beds or bedsets bounded by marine-flooding...
• Parasequence boundaryA surface that separates genetically related strata, representing a marine flooding surface or its...
• Parasequence setA succession of genetically related parasequences that form a distinctive stacking pattern, often bounded by...
• PARCOMAn abbreviation for the Paris Commission, which was the precursor to the OSPAR Convention, focusing on...
• Partial completionA well completion technique where only a portion of the productive reservoir interval is perforated or open...
• Partial penetrationA condition where a wellbore does not fully extend through the entire thickness of a productive reservoir...
• Participating interestA share in an oil and gas venture that typically includes both the right to receive a portion of the...
• Particle-plugging apparatusA laboratory device used to evaluate the ability of drilling fluid to seal permeable formations and prevent...
• Particle-plugging testA laboratory procedure conducted to evaluate the ability of a drilling fluid to seal permeable formations and...
• Particle-size distributionThe range of sizes of solid particles suspended within a drilling fluid, expressed as a percentage or...
• PartitioningThe distribution of a chemical substance between two immiscible phases, such as oil and water, in a...
• Parts per billionA unit of concentration representing one part of a substance per billion parts of the total mixture by mass...
• Parts per millionA unit of concentration representing one part of a substance per million parts of the total mixture, often...
• PartyA crew of geophysicists, technicians, and support personnel organized to conduct a seismic survey in the...
• Party chiefThe individual responsible for the overall management and technical supervision of a seismic acquisition crew...
• Party managerThe individual responsible for the overall management and technical supervision of a seismic acquisition crew...
• PascalThe SI unit of pressure or stress, defined as one newton of force applied over an area of one square meter...
• PassA single trip of a wireline logging tool assembly up or down the wellbore to acquire data. A main pass is the...
• Passive marginA continental margin that is not an active plate boundary, characterized by a broad continental shelf, slope...
• PatchA group of receiver lines that are live and recording for a given shot in a land 3D survey, forming the...
• PayA rock formation or interval within a wellbore that contains hydrocarbons in sufficient quantities to be...
• PayoutThe point in time when the cumulative net revenue from a well or project equals the total capital investment...
• PDMA downhole motor powered by the flow of drilling fluid, used to rotate the drill bit independently of the...
• PeakThe point of maximum positive amplitude on a seismic trace, representing a crest in the waveform. In seismic...
• Peak shavingThe practice of reducing short-term high demand for natural gas, particularly during cold weather or other...
• PEFThe photoelectric factor, the effective photoelectric absorption index per electron of the formation, which...
• Peg-leg multipleA multiple that reflects at different interfaces on its downward and upward legs, so its path is not...
• Pendant-drop tensiometerAn optical instrument that measures interfacial tension between two immiscible fluids by analyzing the shape...
• Penetration rateThe speed at which a drill bit breaks through rock, also known as the rate of penetration (ROP). It is...
• PeptizationThe dispersion of aggregated colloidal particles, such as bentonite clay, into a stable suspension of...
• PeptizeTo disperse aggregated solid particles into a stable colloidal suspension within a drilling fluid. This...
• Peptized clayClay particles that have been dispersed into a stable colloidal suspension within a drilling fluid, rather...
• Peptizing agentA chemical additive that disperses clay particles in drilling mud by reducing the attractive forces between...
• PerforateTo create holes through the casing, cement, and into the reservoir rock of a wellbore, establishing a flow...
• Perforate overbalancedTo create perforations in a wellbore while the pressure within the wellbore is intentionally maintained...
• Perforate underbalancedTo create perforations in a cased wellbore while the hydrostatic pressure of the fluid in the well is...
• Perforated intervalThe specific section of the wellbore where perforations have been created to allow fluid flow between the...
• Perforated linerA section of casing or tubing that has holes pre-drilled or punched in it before being lowered into a well...
• Perforating acidAn acid solution, usually hydrochloric acid (HCl), injected into a wellbore immediately before, during, or...
• Perforating chargeA shaped explosive device designed to create a high-velocity jet that penetrates casing, cement, and...
• Perforating depth control logA specialized wireline log run in a wellbore to precisely determine the depth of the perforating guns...
• Perforating fluidA clean, solids-free liquid, such as filtered brine, left in the wellbore across the interval when the guns...
• Perforating gunA downhole tool containing shaped explosive charges designed to create perforations through the casing...
• PerforationA hole or channel created through the casing, cement sheath, and into the surrounding reservoir rock...
• Perforation densityThe number of perforations created per linear foot of wellbore in a given interval. This parameter is a key...
• Perforation penetrationThe depth to which a shaped charge jet extends beyond the inner wall of the casing, through the cement, and...
• Perforation phasingThe angular separation between adjacent perforating charges around the circumference of a perforating gun...
• PeriodogramA tool used in spectral analysis to estimate the power spectral density of a signal, such as a seismic trace...
• PermafrostGround that remains continuously frozen for two or more consecutive years, consisting of soil, rock, or...
• Permanent datumThe fixed elevation reference to which the well's depths and elevations are tied, recorded on the log header...
• Permanent well monitoringThe continuous, long-term collection of downhole and surface data from a producing well using permanently...
• PermeabilityA measure of the ability of a porous rock to allow fluids to flow through it, quantifying the...
• Permeability thicknessThe product of the effective permeability (k) of a reservoir and its net pay thickness (h), often denoted as...
• PermeableDescribing a rock or sediment that has interconnected pores, allowing fluids like oil, gas, or water to flow...
• PermeameterA laboratory instrument used to measure the permeability of rock samples, typically core plugs. It works by...
• PermittivityA measure of a material's ability to store electrical energy in an electric field, influencing the speed of...
• Perpendicular offsetThe horizontal distance measured at a right angle from a seismic source line to a receiver line. This...
• Perpendicular resistivityThe electrical resistivity measured in a direction perpendicular to the bedding planes of a formation. This...
• Petal basket flowmeterA production logging flowmeter whose spring-loaded metal petals open against the casing wall to form a basket...
• PetrographicRelating to the description and classification of rocks, particularly through microscopic examination of thin...
• PetrographyThe scientific study and description of rocks, focusing on their mineralogical composition, texture, and...
• PetroleumA naturally occurring complex mixture of hydrocarbons, found in liquid (crude oil) or gaseous (natural gas)...
• Petroleum systemA natural system that encompasses all the geological elements and processes necessary for oil and gas...
• Petroleum systems modelingA computational approach that simulates the geological processes involved in the formation, migration...
• PetrologicRelating to petrology, the branch of geology that studies the origin, composition, structure, and alteration...
• PetrologyThe scientific study of rocks, encompassing their formation, composition, classification, and the processes...
• Petrophysical modelA mathematical relationship or set of equations that describe how reservoir rock and fluid properties are...
• Petrophysical rock typeA classification of reservoir rock based on its petrophysical properties, such as porosity, permeability, and...
• PfA symbol representing the phenolphthalein alkalinity of a drilling fluid filtrate, measured in milliliters of...
• pHA measure of the acidity or alkalinity of a fluid, expressed on a logarithmic scale from 0 to 14. It...
• pH testThe measurement of the acidity or alkalinity of a drilling fluid, made either with pH paper for a rough value...
• PhantomA synthetic seismic horizon created by shifting a real seismic horizon up or down by a constant time or depth...
• PhaseThe position of a point on a seismic waveform relative to a reference point or the start of a cycle, measured...
• Phase redistributionThe dynamic movement and rearrangement of different fluid phases (oil, gas, water) within a wellbore or...
• Phase shiftThe angular difference in the phase of an electromagnetic wave transmitted into the formation compared to the...
• Phase velocityThe speed at which a point of constant phase on a monochromatic wave propagates through a medium. In seismic...
• Phase velocity logA production log that records the velocity of an individual fluid phase, usually oil or water, moving in a...
• Phase-shift resistivityA resistivity measurement derived from the phase shift of an electromagnetic wave propagating through the...
• PhenolphthaleinAn organic compound used as an indicator in drilling fluid titrations to determine alkalinity. It is...
• Phosphate saltA chemical compound containing a phosphate ion, used in drilling fluids primarily as a deflocculant or...
• Photoelectric effectAn interaction where a photon transfers all its energy to an atomic electron, causing the electron to be...
• Photon logA log of the density of the material surrounding a completed well, recorded with a radioactive gamma-ray...
• PHPAAn abbreviation for partially hydrolyzed polyacrylamide, a synthetic polymer commonly used as a shale...
• PHPA mudA water-based drilling fluid system that incorporates partially hydrolyzed polyacrylamide (PHPA) as a primary...
• Physics-informed aiA type of artificial intelligence that incorporates principles of physics, such as fluid dynamics or...
• PIAn abbreviation for productivity index, which is a measure of a well's ability to produce fluids from the...
• PickTo identify and mark a specific event or horizon on a seismic trace or section, typically representing a...
• Pickett plotA cross-plot of resistivity versus porosity on a log-log scale, used to determine formation water resistivity...
• PickleTo circulate a specialized fluid through a wellbore or tubular string to clean it, remove debris, or prepare...
• Pickling fluidAn acidic solution, typically containing hydrochloric acid and corrosion inhibitors, used to clean the...
• PigA device sent through a pipeline to clean it, inspect its integrity, or separate different fluid batches...
• Pig runThe operation of propelling a pig through a pipeline from a launch point to a receiving point. This process...
• PiggingThe practice of using a pig to clean, inspect, or separate products within a pipeline. This method maintains...
• PillA small, concentrated volume of drilling fluid with specific properties, pumped into the wellbore to address...
• Pilot millA downhole cutting tool with a smaller-diameter, protruding guide section at its tip, designed to enter and...
• Pilot testA small-scale laboratory experiment conducted to evaluate the performance of drilling fluid additives or...
• Pilot-operated regulatorA type of pressure regulator where a small, auxiliary regulator, known as the pilot, controls the main...
• PinThe male threaded end of a drill pipe, casing, or tubing joint that connects into the box (female end) of...
• Pinch outThe lateral termination of a rock layer where its thickness progressively thins to zero, ending against...
• Pinion shaftThe component of a gear system that carries the smaller of two meshing gears, known as the pinion. In a...
• Pipe dopeA specialized lubricant and sealant applied to the threads of tubular connections, such as drill pipe...
• Pipe heavyA condition in which the weight of the pipe string in the hole is greater than the upward force that wellbore...
• Pipe lightA condition in which the upward force that wellbore pressure exerts on the cross-section of the pipe string...
• Pipe rackA designated area on the rig floor or adjacent to it where sections of drill pipe, casing, or tubing are...
• Pipe ramA component of a blowout preventer (BOP) that seals around the drill pipe or casing in the wellbore. It...
• Pipe stretchThe elongation of a drill pipe or tubing string under tensile load, caused by its own weight and the forces...
• Pipe tripThe operation of pulling the drill string out of the wellbore (tripping out) and then running it back in...
• PipelineA system of interconnected pipes used for the long-distance transportation of fluids, such as crude oil...
• Pipeline capacityThe maximum volume of fluid, typically measured in barrels per day for liquids or cubic feet per day for gas...
• Pipeline gasNatural gas that meets specific quality and pressure specifications for transportation through a pipeline...
• Pipeline oilCrude oil or refined petroleum products that meet specific quality and pressure specifications for...
• Pipeline patrolThe systematic inspection of a pipeline right-of-way to detect potential hazards, leaks, or unauthorized...
• Piston effectThe force exerted on a drill string or tubing string by differential pressure acting across a change in...
• PITAn abbreviation for pressure integrity test, a test of the open formation just below a new casing shoe in...
• Pitch-and-leadTwo related measurements of a screw thread: pitch is the axial distance between corresponding points on...
• Pitot tubeA device used to measure the local velocity of a fluid flow by determining the difference between the...
• PittingA localized form of corrosion that creates small, deep holes or cavities on a metal surface, rather than...
• Plane tableA surveying instrument used for mapping in the field, consisting of a drawing board mounted on a tripod with...
• Plane waveA theoretical wave whose wavefronts are infinite parallel planes and whose direction of propagation is...
• PlanktonMicroscopic organisms, both plant (phytoplankton) and animal (zooplankton), that drift in marine and...
• PlantTo embed a seismic geophone or sensor firmly into the ground to achieve good coupling with the Earth's...
• PlasticDescribing a material's ability to undergo permanent deformation without fracturing when subjected to stress...
• Plastic deformationPermanent change in the shape or volume of a rock body without fracturing, occurring when stress exceeds the...
• Plastic fluidA non-Newtonian fluid that exhibits a yield point, meaning it requires a certain amount of shear stress to...
• Plastic viscosityA measure of the resistance of a drilling fluid to flow caused by mechanical friction between solid particles...
• Plate outAdhesion of radioactive tracer material to the casing, perforations or formation face instead of travelling...
• Plate tectonicsThe scientific theory describing the large-scale motion of Earth's lithosphere, which is broken into several...
• PlateauAn extensive area of elevated, relatively flat-lying land that is bounded on at least one side by a steep...
• PlatformA stable, relatively flat area of the continental crust that has remained tectonically undisturbed for long...
• PlayA geological concept describing a group of oil and gas accumulations or prospects that share a common set of...
• Play backTo re-process or re-display previously recorded logging data, often with different parameters or processing...
• PlaybackThe re-processing or re-display of previously acquired logging data, often with adjusted parameters or...
• PLTA production logging tool, which is a downhole instrument used to measure fluid flow rates, fluid types, and...
• Plug and abandonTo permanently seal a wellbore with cement plugs and other barriers to prevent the migration of fluids...
• Plug flowA flow regime in multiphase flow where large, bullet-shaped gas bubbles, known as Taylor bubbles, move...
• Plug valveA quarter-turn valve that uses a cylindrical or tapered plug with a bore through it, which rotates 90 degrees...
• Plugging materialAny substance added to a drilling fluid to seal off permeable formations or lost circulation zones in the...
• PlungeThe angle at which the axis of a fold or a linear geological feature dips downward from the horizontal...
• Plunger liftAn artificial lift method that uses a free-traveling piston, or plunger, to remove accumulated liquids from...
• Plunger overtravelA condition in sucker rod pumping where the plunger at the subsurface pump travels a longer stroke than the...
• PmThe phenolphthalein alkalinity of whole mud, found by diluting a small mud sample in distilled water, adding...
• PNPThe abbreviation for propylene glycol n-propyl ether, a glycol ether solvent with the formula C6H14O2, made...
• Point barA depositional feature made of sand and gravel that accumulates on the inside bend of a meandering river or...
• PoiseA unit of dynamic viscosity in the centimeter-gram-second (CGS) system of units, representing the tangential...
• Poisson distributionA discrete probability distribution that models the number of independent events occurring within a fixed...
• PolarDescribing a molecule that possesses a net electrical dipole moment due to the uneven distribution of...
• Polar compoundA chemical substance composed of molecules that have a net electrical dipole moment, meaning there is an...
• PolarityThe sign convention for seismic reflections, indicating whether an increase in acoustic impedance at a...
• Polarity standardA convention or reference used to define the expected seismic waveform response for a specific geological...
• Polarization hornA sharp, spurious spike on an induction log curve that appears at the boundary between a highly resistive bed...
• Polarization timeThe duration for which a static magnetic field is applied to a formation before a nuclear magnetic resonance...
• Polished jointA joint of tubing or pipe whose outside surface is ground and polished to serve as a sealing surface. It...
• Polished rodA smooth, high-strength steel rod that connects the pumping unit's walking beam to the sucker rod string in a...
• PolyacrylamideA synthetic polymer used in enhanced oil recovery as a mobility control agent in polymer flooding. It...
• PolyacrylateA synthetic polymer derived from acrylic acid or its esters, used as a drilling fluid additive to modify...
• Polyalkalene glycolA synthetic polymer used as a shale inhibitor and lubricant in water-based drilling fluids. It functions by...
• PolyalphaolefinA synthetic hydrocarbon fluid used as a base oil in non-aqueous drilling fluids, particularly in...
• Polyanionic celluloseA water-soluble polymer derived from cellulose, used as a drilling fluid additive for fluid loss control and...
• Polyanionic ligninA modified natural polymer derived from lignin, used as a deflocculant and fluid loss control agent in...
• Polycrystalline diamond compact (PDC) bitA type of drill bit that uses synthetic diamond cutters, known as polycrystalline diamond compacts, bonded to...
• PolyelectrolyteA polymer whose repeating units bear an electrolyte group, meaning they can dissociate into charged ions in a...
• PolymerA large molecule composed of many repeated smaller molecular units, known as monomers, linked together in a...
• Polymer floodingAn enhanced oil recovery method that injects water thickened with a polymer into a reservoir to improve sweep...
• Polymer plugA temporary or permanent barrier created in a wellbore using a viscous polymer solution that sets or...
• PolyolAn organic compound containing multiple hydroxyl groups, used in drilling fluids as a component in synthetic...
• PolyolefinA polymer made from simple olefin monomers such as ethylene or propylene, giving polyethylene and...
• PolyphosphatesA class of chemical compounds used as deflocculants and thinners in freshwater-based drilling fluids to...
• PolysaccharideA carbohydrate polymer built from many monosaccharide units joined by glycosidic bonds. In enhanced oil...
• Pony rodA short sucker rod used in a rod pumping system, typically installed between the polished rod and the main...
• POOHTo pull out of the hole, referring to the action of withdrawing the drill string or tubing from the wellbore...
• PoolingThe combining of small or irregular tracts of land into a drilling unit large enough to satisfy state spacing...
• Poppet valveA type of valve that uses a disc or cone-shaped element, called a poppet, to control fluid flow by moving...
• PoreA void or open space within a rock, not occupied by solid mineral matter, that can contain fluids such as...
• Pore gasGas occupying the pores of reservoir rock as a free phase, a quantity also called interstitial gas and...
• Pore pressureThe pressure exerted by fluids within the pore spaces of a rock formation. This pressure, also known as...
• Pore throatThe narrowest constriction within the pore network of a rock that connects larger pore bodies. These...
• Pore-pressure gradientThe rate of change of pore pressure with depth in a formation. It is calculated by dividing the pore pressure...
• Pore-pressure transmissionThe process by which hydrostatic pressure from the drilling fluid column is transferred through the filter...
• PorosimeterA laboratory instrument used to measure the porosity of rock samples, typically core plugs. It works by...
• PorosityThe fraction of a rock's bulk volume occupied by pore space, expressed as a percentage or a decimal. Total...
• Porosity exponentAn empirical constant, denoted as 'm', used in the Archie equation to relate the formation resistivity factor...
• Porosity unitA measure of the pore volume within a rock, expressed as a percentage or a fraction of the total rock volume...
• PorousDescribing a rock or material that contains numerous small voids or pore spaces. Porous rocks are capable of...
• Porous mediumA material containing interconnected pores or voids through which fluids can flow, such as reservoir rock...
• Porous plate techniqueA laboratory method used to determine the capillary pressure characteristics of a rock sample. A saturated...
• Portland cementA hydraulic cement, primarily composed of calcium silicates, used in oil and gas wells for cementing...
• Portland cement clinkerThe intermediate product formed by heating limestone and clay or other materials to high temperatures in a...
• Positive displacement motorA downhole motor that converts the hydraulic energy of drilling fluid into mechanical energy to rotate the...
• Positive displacement pumpA type of pump that delivers a fixed volume of fluid with each revolution or stroke of the pumping element...
• PostTo display a data value at its corresponding map coordinate location (x, y) on a basemap or cross-section...
• PostmatureDescribing a source rock that has been subjected to temperatures and pressures beyond the optimal range for...
• PotassiumA naturally radioactive element whose isotope potassium-40 emits gamma rays at 1.46 MeV, an energy that lets...
• Potassium ionA positively charged ion of potassium (K+), commonly introduced into drilling fluids to inhibit the hydration...
• Potassium mudA type of water-based drilling fluid containing potassium ions, typically from salts like potassium chloride...
• Potential fieldA physical field, such as gravity or magnetism, that can be described by the gradient of a scalar potential...
• Pounds per barrelA unit of concentration used in drilling fluids, representing the weight of a solid additive in pounds per...
• Pour pointThe lowest temperature at which a liquid, such as a crude oil or drilling fluid, will flow when cooled under...
• Power oilCrude oil that has been processed and cleaned to be used as the hydraulic fluid in a subsurface hydraulic...
• Power-fluid injection rateThe volume of hydraulic fluid, often treated crude oil, pumped downhole per unit of time to operate a...
• Power-law fluidA non-Newtonian fluid model used to describe the rheological behavior of drilling fluids, where the shear...
• PozzolanA siliceous or aluminous material that, when finely ground and mixed with water, reacts with calcium...
• PozzolanicDescribing a siliceous or aluminous material that reacts with calcium hydroxide in the presence of water to...
• PPAThe abbreviation for the permeability plugging apparatus, also called the particle plugging apparatus, a...
• PpbAn abbreviation for pounds per barrel, a unit of concentration used in drilling fluids to express the amount...
• PpgAn abbreviation for pounds per gallon, the standard unit of measurement for drilling fluid density, or mud...
• PpmAn abbreviation for parts per million, a unit of concentration used to express very small quantities of a...
• PrecipitateTo form an insoluble solid from a solution, either by a chemical reaction or by a change in physical...
• PrecipitationThe process by which a solid forms and separates from a liquid solution. In drilling fluids, precipitation...
• PrecisionThe degree of reproducibility of a measurement, indicating how closely repeated measurements agree with each...
• Predictive aiArtificial intelligence that uses historical data and statistical algorithms to forecast future outcomes or...
• Preferential right to operateA contractual right that a party reserves for itself or obtains from others to serve as operator of a lease...
• Preferential right to purchaseA contractual clause, commonly found in joint operating agreements, that gives a party the first opportunity...
• PreflushA slug of fluid injected into a reservoir ahead of the main displacing fluid in an enhanced oil recovery...
• Pregelatinized starchA modified starch product used as a fluid loss control additive in water-based drilling fluids. It is...
• PrehydrateTo mix bentonite or other polymers with fresh water to allow them to fully swell and yield before being added...
• Prehydrated bentoniteBentonite clay that has been mixed with water and allowed to hydrate for a period before being added to the...
• PrehydrationThe process of mixing bentonite clay or certain polymers with fresh water to allow for full hydration and...
• Premium threadA specialized connection design for oilfield tubulars, such as casing and tubing, featuring a metal-to-metal...
• PreservationThe processes that prevent the degradation or destruction of organic matter after its deposition, allowing it...
• PreservativeA chemical additive used in water-based drilling fluids to inhibit the growth of bacteria and other...
• Preserved coreA rock sample taken from a wellbore that has been treated to maintain its original reservoir conditions, such...
• PressureThe force exerted per unit area within a fluid or by a fluid on its boundaries. In well testing, it is a...
• Pressure buildupA well test conducted by shutting in a producing well and recording the increase in bottomhole pressure over...
• Pressure buildup analysisA well test technique where a producing well is shut in, and the subsequent increase in bottomhole pressure...
• Pressure capabilityThe maximum internal pressure a component or system can withstand without failure or permanent deformation...
• Pressure depletionThe reduction in reservoir pressure over time due to the withdrawal of fluids. This decline is a natural...
• Pressure drawdownThe difference between the static reservoir pressure and the flowing bottomhole pressure at a given...
• Pressure falloffThe decline in bottomhole pressure that follows shutting in an injection well, recorded over time as the...
• Pressure gaugeAn instrument used to measure the pressure of fluids or gases in a wellbore or surface equipment. These...
• Pressure gradientThe rate at which pressure changes with respect to distance, particularly with vertical depth in the...
• Pressure integrity testA test performed after cementing a casing string to verify the strength of the cement bond and the formation...
• Pressure senderAn electronic device that measures pressure and converts it into an electrical signal for transmission to a...
• Pressure storage tankA vessel designed to hold fluids or gases at pressures significantly higher than ambient, typically used for...
• Pressure transient analysisA technique used to interpret pressure and flow rate data acquired during well tests to determine reservoir...
• Pressure transient testA diagnostic procedure involving the controlled change of a well's production rate and the subsequent...
• Pressure transient well testA diagnostic procedure involving the controlled manipulation of a well's production rate or injection rate to...
• Pressure-composition diagramA graphical representation showing the phase behavior of a multi-component fluid mixture as a function of...
• Pressure-drawdown analysisA well test method where a well is flowed at a constant rate, and the resulting pressure decline is measured...
• Pressure-squared plotA graphical analysis technique for gas well test data that plots the square of the bottomhole pressure (p²)...
• Pressurized mud balanceA specialized instrument used to accurately measure the density of drilling fluids, particularly those...
• Primary cementingThe process of pumping cement slurry into the annulus between the casing and the wellbore after the casing...
• Primary completion componentsThe main set of downhole equipment installed in a well to control production and enable safe and efficient...
• Primary migrationThe initial movement of hydrocarbons from their source rock into adjacent carrier beds or reservoir rocks...
• Primary porosityThe original pore space within a sedimentary rock that was created at the time of deposition, before any...
• Primary productionThe initial phase of oil and gas recovery that relies on natural reservoir energy to drive hydrocarbons to...
• Primary recoveryThe initial phase of oil and gas production where hydrocarbons are recovered from a reservoir using only...
• Primary recovery methodThe initial phase of hydrocarbon production from a reservoir, relying on natural reservoir energy to drive...
• Primary reflectionA seismic reflection that has traveled directly from the source to a subsurface interface and then directly...
• Primary termThe initial period specified in an oil and gas lease during which the lessee has the right to explore for and...
• Prime moverThe engine or motor that provides the primary power source for the drilling rig's operations. These typically...
• Primer cordA flexible cord containing a high explosive material, used to initiate detonation in other explosive devices...
• Principal axisOne of three mutually perpendicular directions in space used to describe the orientation and magnitude of a...
• Principal component analysisA statistical procedure that transforms a set of possibly correlated variables into a set of linearly...
• Private cloudA cloud computing environment dedicated to a single organization, providing exclusive access to its...
• ProbabilityA numerical measure of the likelihood that an event will occur, expressed as a value between 0 and 1. In...
• ProbeA small, specialized sensor or instrument designed to measure physical properties in a localized area, often...
• ProcessingThe application of mathematical and statistical operations to raw geophysical data to enhance signal quality...
• Produced fluidAny fluid, including oil, gas, water, and solids, that flows from a reservoir to the surface through a...
• Produced waterWater that is brought to the surface along with oil and gas during production operations, originating from...
• Producing formationA geological rock layer or zone within a reservoir that contains economically recoverable hydrocarbons and...
• Producing wellA well that is actively extracting hydrocarbons, such as oil or natural gas, from a subsurface reservoir...
• ProductionThe process of extracting hydrocarbons, such as crude oil or natural gas, from a reservoir to the surface...
• Production bonusA payment that a contractor or licensee owes to the host government or lessor when production first reaches a...
• Production casingThe final string of steel pipe set in a wellbore, extending from the surface to the producing formation...
• Production logA suite of downhole measurements recorded in a producing well to evaluate fluid flow characteristics and...
• Production packerA downhole device set in the casing to provide a seal between the production tubing and the casing annulus...
• Production paymentA share of the gross production of oil and gas, free of the costs of development and operation, that...
• Production penaltyA fine that a contractor pays to the host government when it fails to reach the production rates set in the...
• Production periodThe duration during which a well is actively flowing hydrocarbons from the reservoir to the surface. This...
• Production service contractAn upstream agreement in which a contractor develops or operates fields for a state or national oil company...
• Production sharing contractA contractual arrangement between a host government and an oil company for the exploration and production of...
• Production stringThe assembly of tubing, packers, and downhole equipment run inside the production casing to convey reservoir...
• Production treeAn assembly of valves, spools, and fittings installed on the wellhead of an oil or gas well to control the...
• Production tubingThe string of pipe through which hydrocarbons flow from the reservoir to the surface. It is run inside the...
• Production wingA lateral flowline or branch connection on a Christmas tree that directs produced hydrocarbons from the...
• Productivity index (PI)A measure of a well's ability to produce fluids, defined as the ratio of the production rate to the pressure...
• Productivity testA well test conducted to determine the relationship between the production rate of a well and the...
• ProfileA cross-sectional view of the subsurface derived from seismic data, typically along a single line or a series...
• Profile modificationA stimulation technique used to improve sweep efficiency in a reservoir by altering the flow profile of...
• Profile testingThe process of evaluating the flow characteristics of fluids within a wellbore, often using production...
• ProfilingThe process of acquiring and presenting geophysical data, such as seismic, gravity, or magnetic measurements...
• Profit oilThe portion of oil and gas production remaining after the contractor's costs have been recovered under a...
• ProgradationThe seaward or basinward advance of a shoreline or sedimentary environment due to the accumulation of...
• Progressive cavity pumping systemAn artificial lift system in which a helical steel rotor turns eccentrically inside a fixed elastomer-lined...
• Progressive gelsA characteristic of drilling fluids where the gel strength continues to increase over time when the fluid is...
• PromptThe input text, question, or instruction provided by a user to an artificial intelligence model to elicit a...
• Prompt engineeringThe process of designing, refining, and structuring text inputs to guide a generative artificial intelligence...
• Propagation constantA complex quantity that characterizes how a wave's amplitude and phase change as it propagates through a...
• Propagation resistivityA resistivity derived from the attenuation and the phase shift of a high-frequency electromagnetic wave...
• Propagation resistivity measurementA technique used in logging-while-drilling (LWD) tools to determine formation resistivity by measuring the...
• Propagation timeThe time a high-frequency electromagnetic wave takes to travel a unit distance through the formation, as...
• ProppantA granular material, such as sand, ceramic beads, or bauxite, pumped into a hydraulic fracture to keep it...
• Propylene glycol normal propyl etherA propylene-oxide-based glycol ether, 1-propoxy-2-propanol, that is partly soluble in water and miscible with...
• Prorated wellA well whose production rate is limited by regulatory agencies or field operators to prevent overproduction...
• Proration unitAn area of land assigned to a well by a regulatory authority and used to set that well's allowable production...
• ProspectA geological feature or area identified as having the potential to contain economically recoverable...
• Proximity logA pad-mounted focused micro-resistivity log that reads the flushed-zone resistivity Rxo from a depth of a few...
• Pseudogeometrical factorA mathematical concept used in induction logging to describe the contribution of different parts of the...
• PseudoplasticDescribing a non-Newtonian fluid whose viscosity decreases as the rate of shear stress increases, a property...
• Pseudopressure plotA specialized plot used in gas well test analysis that transforms pressure data into pseudopressure to...
• Pseudostatic spontaneous potentialThe spontaneous potential recorded opposite a thick, permeable, shaly bed, which is smaller than the static...
• Pseudosteady stateA flow regime in a closed reservoir, reached after the pressure disturbance has felt every boundary, in which...
• PSPThe pseudostatic spontaneous potential, the spontaneous potential recorded opposite a thick, permeable, shaly...
• Public cloudA cloud computing service model where computing resources, such as servers, storage, and applications, are...
• Pull out of the holeTo withdraw the drill string from the wellbore to perform an operation such as changing the bit, running...
• Pulling toolA downhole tool designed to retrieve equipment or components from a wellbore. It engages with a fishing neck...
• Pull-upAn apparent upward displacement of seismic reflection events on a time section, caused by an overlying...
• Pulse echoA measurement technique that involves transmitting a short burst of energy and then listening for the...
• Pulsed neutron spectroscopy logA well log that measures the elemental composition of formations by analyzing gamma rays emitted after the...
• Pulsed neutron spectroscopy measurementA well logging technique that uses a pulsed neutron generator to irradiate formations and measure the energy...
• Pulsed-neutron holdup logA logging technique that uses a pulsed neutron generator to measure the volumetric fraction of different...
• Pump barrelThe cylindrical housing of a downhole pump, typically made of steel, within which the pump plunger or rotor...
• Pump cavitationThe formation and collapse of vapor bubbles within a pump's fluid stream, caused by a localized drop in...
• Pump manifoldAn assembly of pipes, valves, and fittings that connects multiple pumps to a common suction or discharge...
• Pump submergenceThe vertical distance that a downhole pump, such as an electric submersible pump (ESP), is positioned below...
• Pump volumetric efficiencyThe ratio of the actual fluid volume delivered by a pump to the theoretical volume it should deliver based on...
• PumpabilityThe ability of a fluid, such as drilling mud or cement slurry, to be circulated through the wellbore and...
• PumperAn oilfield operator responsible for monitoring and maintaining production from a group of wells, often...
• Pumping scheduleA detailed, time-based plan specifying the sequence, volumes, rates, and pressures for injecting fluids into...
• Pumping timeThe duration for which a cement slurry remains in a fluid state, allowing it to be pumped downhole before it...
• Pumping wellA well that requires artificial lift, such as a rod pump or electric submersible pump, to bring reservoir...
• Pumping well testsA set of pressure transient analysis procedures conducted on wells that require artificial lift, such as...
• PumpoffA condition in a rod-pumped well where the pump has lifted all available fluid from the wellbore, causing the...
• PushdownAn apparent downward displacement of seismic reflection events on a time section, caused by an overlying...
• PusherSlang for the toolpusher, the drilling contractor's senior supervisor on a rig, who manages the crews...
• PVAn abbreviation for plastic viscosity, a rheological parameter that represents the resistance of a fluid to...
• PVTAn abbreviation for pressure, volume, and temperature, which describes the phase behavior and properties of...
• PyrolysisThe thermal decomposition of organic matter in the absence of oxygen, often used in laboratory settings to...
• PyrophosphateA chemical compound used as a deflocculant or dispersant in water-based drilling fluids to reduce viscosity...
• PyrrhotiteA naturally occurring iron sulfide mineral that can be encountered during drilling operations. It is magnetic...

364 of 4,469 terms in Oil and gas terminology (MLC-0103). Request the full dataset.