C
C.O.S.T. Well
Continental Offshore Stratigraphic Test (C.O.S.T.) well. A stratigraphic well, offshore.
C-axis
The principal crystallographic axis perpendicular to the direction of growth.
Cable
SEE: Seismic Cable.
Cable Seal
A cable terminator filled with compound and designed to contain an explosion in the enclosure to which it is attached. A conduit seal may also be used as a cable seal.
Cable Tool Drilling
A system of drilling employing a heavy string of tools suspended from a walking beam by a cable. Reciprocating motion, imparted to the walking beam by a crank, causes the drill bit at the bottom of the cable to strike the bottom of the wellhole and deepening it by chipping.
Cable Tool Well Flag
An indicator of whether cable tools were used in drilling the well.
Cage
The container for the ball in a ball valve; e.g., found in the subsurface pump ordinarily used in oil production. It holds the ball to limit its movement.
Caisson
A protective tubular device for wells drilled in water locations.
Cake Consistency
Such notations as hard, soft, tough, rubbery, firm, etc., may be used to convey some idea of cake consistency.
Calcareous Coating
A chalky coating of calcium carbonate and/or magnesium hydroxide.
Calcium
One of the alkaline earth elements with a valence of 2 and an atomic weight of about 40. Calcium compounds are a common cause of the hardness of water. It is also a component of lime, gypsum, limestone, etc.
Calcium Carbonate
A slightly soluble calcium salt (limestone, oyster shells, etc.) sometimes used as a weighting material, and also as a standard unit for expressing hardness of water.
Calcium Chloride
A highly soluble calcium salt sometimes added to drilling fluids to impart special properties, but primarily to increase the density of the fluid and to accelerate the hydration reaction of cement and water. Commonly abbreviated as: CaCl2.
Calcium Contamination
Dissolved calcium ions in sufficient concentration to impart undesirable properties in a drilling fluid; e.g., flocculation; reduction in yield of bentonite; increase in fluid loss.
Calcium Hydroxide
The active ingredient of slaked lime. It is also the main constituent in cement (when wet). This material is referred to as lime in field terminology.
Calcium Sulfate
Anhydrite (CaSO4); hemihydrate or plaster of paris (CaSO4 1/2 H2O); and gypsum (CaSO4 2H2O), or a combination of these. Calcium sulfate occurs in drilling fluids as a contaminant or may be added to certain drilling fluids to impart special properties.
Calcium Treated Mud
Drilling fluids to which quantities of soluble calcium compounds have been added or allowed to remain from the formation drilled in order to impart special properties.
Calculated Absolute Open Flow Rate
The rate of flow per 24 hours that would be produced by a well if the only pressure against the face of the reservoir rock within the borehole were atmospheric pressure. Commonly abbreviated as CAOP. Also referred to as: open flow potential.
Calculated Flow Temperature Factor
The calculated temperature correction factor = (520/(460 + line temperature farenheit)).
Calculated Gravity Factor
The specific gravity correction factor = the square root of (1 + the specific gravity of the flowing fluid).
Calculated Pressure
The calculated pressure is the atmospheric pressure + gauge pressure at pressure base.
Calculated Settlement Price
The calculated price to be used in the settlement.
Calculated Super Compressibility Factor
The super compressibility multiplier for use with these meters is = 1/Z.
Calculation Method
SEE: Borehole Survey Calculation Method.
Calendar Day Count
The number of days in a calendar month.
Calibration
Measurement correction by comparison to a standard of known accuracy.
Caliche
A natural unconsolidated limestone occurring over large areas of west and south Texas, often near the surface.
Caliper Log
(1) A record of the diameter of the borehole or the internal diameter of tubular goods. The log indicates undue enlargement of the borehole due to caving, washout, or other causes.(2) Section gauge log: made from tools with many fingers used to measure the corrosion of casing and tubing.
Call
The right to purchase hydrocarbons from an outside party.
Canadian Petroleum Association
Canadian Petroleum Association (cpa) Well Number
The identifier assigned to wells (holes in the ground) drilled in Canada. It defines the approximate geographical location of the bottom of a drilled hole.
Cant Angle
Orientation of sound beam relative to axis of member.
Caof
SEE: Calculated Absolute Open Flow.
Cap
A fitting that goes over the end of a pipe to close it, producing a dead end.
Cap Rock
(1) In a salt dome, an impervious body of anhydrite, gypsum and minor calcite and sulfur that overlies the salt body.(2) Any cap rock can form part of a trap for a hydrocarbon accumulation.
Capable Well
A well with well completions that are physically capable of producing at a specified level for a specified time period. Some of these wells may be actually producing while others are shut in for reasons other than their ability to produce. (Normally at a lease or field level.).
Capacitor
An electrical device that, when wired in the line of an electrical circuit, stores a charge of elecricity and returns the charge to the line when certain electrical conditions occur.
Capacity
Maximum throughput, maximum producing rate, or maximum content possible for a given set of conditions.
Capacity Allocation
A process by which capacity available in a pipeline is distributed to parties in the event requests for quantitiies (i.e., nominations) are in excess of the available space. Typically the allocation is based on service type, contract type, and a company's tariff provisions.
Capacity Index
An indication of the capacity of an injection well to take water. It is usually measured in barrels per hour per pound increase in bottomhole pressure.
Capacity Reduction Factor
Coefficient which accounts for the effects of shape imperfections, nonlinear behavior and boundary conditions (other than classical simply supported) on the buckling capacity of the shell.
Capillary Number
The ratio of capillary to viscous forces on fluids in a porous media.
Capillary Pressure Measurement
The difference in pressure existing between two phases or fluids, measured at points of the interconnected phases.
Capillary Water Rise
The rise of water in a loosely compacted material such as a sand fill, due to capillary forces.
Capital Asset
The assets intended for long, continued use or possession. May be further classified as tangible; e.g., land, buildings, and intangible; i.e., the costs of drilling a well other than materials.
Capital Investment
Funds spent to acquire additions to assets for the betterment of the operation. Depreciation is taken on such expenditures rather than charging them off as expense or operating cost.
Capping A Well
A method by which the uncontrolled flow of a well is stopped or controlled in order to temporarily abandon a well.
Carbon Black
A fine, bulky carbon obtained as soot by burning natural gas in large horizontal ovens with insufficient air.
Carbon Dioxide
A colorless, odorless, nonpoisonous gas that is a normal part of ambient air. Dissolved in the aqueous phase of drilling fluids, C02 may contribute to corrosivity of these fluids or to unstable rheological properties.
Carbon Dioxide Content
Carbon dioxide content of the sample.
Carbon Dioxide Encountered Depth
The depth at which carbon dioxide is encountered in the wellbore.
Carbon Oxygen Log
A log which presents a measure of the relative abundance of carbon to oxygen derived from induced gamma ray spectroscopy.
Carbonate Analysis Log
A log which presents computed porosity in complex lithology and sometimes includes secondary porosity and movable oil plots.
Carcinogen
A substance or agent producing or inciting cancerous growths in living tissues.
Cardiopulmonary Resuscitation
To revive the heart and lungs from apparent death or unconsciousness. Commonly referred to as CPR.
Carried Interest
SEE: Carried Working Interest.
Carried Working Interest
An agreement under which one party (carrying party) agrees to pay a portion or all of the development and operating costs applicable to the working interest owned by another party (carried party). The carrying party has the right to recover such costs from the carried party's share of the reserves if, as, and when produced from the property.
Carrier Gas
One of two phases in the gas chromatography process. It carries the components through the stationary bed.
Carter Coordinates
The surface location established by the Carter Grid System occurs in the following sequence: township number and direction, range number and direction and section. Used in Kentucky and Tennessee.
Carter Grid System
A rectilinear system of township, range and section for a surface location to locate parcels of land. System used in Kentucky and Tennessee.
Carter Range
In Kentucky and Tennessee where the Carter Coordinate System is used, this is a strip of land 5 miles wide, running east and west, parallel to a baseline, and is consecutively numbered east and west from that principal meridian line. When used in conjunction with a township number, it forms a parcel of land to define a quadrangle, each of which consists of 25 one-square-mile sections.
Carter Range Direction
Provides unique range direction values for the Carter Township Area.
Carter Range Number
The range number assigned in the Carter Coordinate System to uniquely identify a strip that runs east and west.
Carter Reference Latitude
The latitude used to calculate the township, range, and section for a surface location by the Carter Grid System.
Carter Reference Longitude
The longitude used to calculate the township, range, and section for a surface location by the Carter Grid System.
Carter Survey System
The rectilinear grid system of township, range and section with an origin at a reference latitude and longitude.
Carter Township
In Kentucky and Tennessee where the Carter Coordinate System is used, this is a strip of land 5 miles wide, running north and south, parallel to a baseline, and is numbered consecutively north or south from that baseline. When used in conjunction with a range number, it forms a a parcel of land to define a quadrangle. Each of the quadrangles consist of 25 one square mile sections.
Carter Township Direction
Township directional information provides unique township direction values for the Carter Township Area.
Carter Township Number
The number designating a township position south or the letter designating the township position north of the base line.
Carved-out Production Payment
Production payment in which the owner of the royalty or working interest sells a production payment while retaining the residual interest in the property.
Case File Number
An identifier which relates operator,assessment type, processing period, etc to leases, communitization agreements, participating areas, unit agreements, royalty agreements, gas storage agreements, and development contracts.
Cased Hole
A wellbore segment within which casing has been run.
Cash Advance Exercised Iflag
An indicator of whether or not special provisions have been made in the operating agreement which require nonoperators to make cash advances. Most contracts require a provision for cash advances on joint properties.
Cash Contribution
Amounts paid in cash only and will exclude the value of interest in acreage contributed. Such cash contributions are applicable to bottomhole/dry hole contribution.
Casing
Steel pipe installed in the wellbore of a well as drilling progresses. The functions of casing are: (a) to prevent the wall of the borehhole from caving into the wellbore during drilling; (b) to provide control of the well if it tries to blow out; (c) to limit fluid production to the wellbore segment that was perforated or left open.
Casing Above Mudline Height
The distance that a casing is cut above the mudline.
Casing Average Pressure Measurement
The average measured casing pressure at a given point, usually the surface.
Casing Cement
Cement used to hold the casing in place in the borehole.
Casing Cementing Movement
The type of pipe movement used during cementing to improve cement bonding to the formation wall; e.g., reciprocate; rotate.
Casing Centralizer
A device that is secured around the casing to centralize the pipe in the borehole and thus provide a uniform cement sheath around the pipe.
Casing Clamp
Two heavy steel bars that support casing in a wellbore.
Casing Collar Locator
A logging tool used to locate casing collars and other features of downhole hardware; e.g., packers, which often serve as reference depths in subsequent completion operations.
Casing Collar Log
A record of casing collar responses with depth as measured by a casing collar locator.
Casing Cut Below Mudline Depth
The distance that the casing is cut below the mudline.
Casing Cut Flag
A flag used to indicate whether the well's casing is cut and removed.
Casing Failure Date
The date when the casing failure was first detected.
Casing Failure Reason
The primary reason for casing failure; e.g., stuck, corrosion, wear, burst pressure, tension.
Casing Flange
A flange affixed at the top of the casing string used to attach production equipment; i.e., Christmas tree.
Casing Flange Elevation
The elevation of casing flange.
Casing Flow
SEE: Annular Flow.
Casing Grade Code
An indicator of the grade given to the material properties of casing that fall within the tolerances set by API specifications; e.g., H40, J55, K55. SEE ALSO: Tubular Grade Code.
Casing Hanger
A mechanism used to support a casing string in a casinghead by gripping the pipe with wedge type members.
Casing Hanger (threaded)
A mechanism used to support a casing string in a casinghead by means of a male or female thread attached to the casing.
Casing Hanger Type
The type of slip device used to attach the liner to the casing.
Casing Inside Diameter
The inside diameter of the casing.
Casing Inspection Log
A record of casing condition as measured using a method of relating the effects of eddy currents on a magnetic field to casing wall thickness.
Casing Integrity Requirement
A statement of the pressure integrity checks that have to be made against an installed casing string. Typically, one would be required immediately after a string is installed. Others may subsequently be required to satisfy casing wear concerns or prior to making a critical commitment; e.g., before running a completion string.
Casing Maximum Outside Diameter
The maximum outside diameter of the casing run into the wellbore.
Casing Maximum Pressure Measurement
The maximum measured casing pressure measurable within the tubing.
Casing Minimum Inside Diameter
The minimum inside diameter of the casing run into the wellbore.
Casing Outside Diameter
The outside diameter of the casing.
Casing Point
Point in cased wellbore of cementing through perforations. Commonly abbreviated as: CP.
Casing Potential Profile Log
A record of electrical potential of the casing at various levels to detect current entering or leaving the casing. The amount of cathodic protection needed can be determined and results monitored.
Casing Pressure Measurement
(1) Pressure measurable in the annular space between casing strings, casing and tubing, or casing and drill pipe.(2) Pressure measurable at a wellhead casing outlet.
Casing Removed Length
SEE: Tubular Removed Length.
Casing Section
Identifies a contiguous casing string interval with identical tubular and connection properties.
Casing Section Plan
Proposed design of all casing string sections required to drill the wellbore.
Casing Set Date
The date the casing string was set within a wellbore.
Casing Shoe
A short, heavy, hollow cylindrical steel section, beveled on the bottom edge, which is placed on the end of the casing string to serve as a reinforcement and to aid in cutting off minor projections from the borehole wall as the casing is being lowered.
Casing Shoe Depth (logger)
Depth of the casing shoe for a logging run.
Casing Shoe Measured Depth
The measured depth of the casing shoe being cemented.
Casing Shut-in Pressure Measurement
The pressure measurement recorded within a shut-in casing string.
Casing String
The casing run into a wellbore; e.g., surface string; intermediate string; production string.
Casing String Measured Bottom Depth
The measured depth to the bottom of the casing string run into a wellbore; e.g., surface string, intermediate string, production string.
Casing String Measured Top Depth
The measured depth to the top of the casing string.
Casing String True Vertical Bottom Depth
The true vertical depth to the bottom of the casing string run into a wellbore; e.g., surface string, intermediate string, production string.
Casing String True Vertical Top Depth
The true vertical depth to the top of the casing string.
Casing Temperature
The temperature inside the casing.
Casing Tool Type
Type tool used on casing; e.g., rigid centralizers, spud scratchers, frac baffle.
Casing Tubing Connector Type
Type of casing or tubing connector according to that particular thread manufacturer; e.g., 8 RD ST&C, 8 RD LT&C, buttress, hydril FJ-P, atbrad FL-3S.
Casing Type Code
An indicator of the type of casing or tubing that is being run; e.g., conductor casing, intermediate casing, surface casing, liner, tubing.
Casing Weight
The weight of the casing expressed as weight per unit length.
Casinghead
A heavy, steel, flanged fitting that connects to the surface string of casing and provides a housing for the slips and packing assemblies by which intermediate strings of casing are suspended and the annulus sealed off.
Casinghead Gas
SEE: Solution Gas.
Casinghead Gas Production Volume
The total volume of casinghead gas the well/reservoir produced for the specified period of time.
Casinghead Gas Purchase Contract
Agreement covering the sale of casinghead gas by a producer to a plant for the purpose of processing.
Casinghead Housing
Equipment attached to the uppermost end of the surface casing which serves to suspend and seal a casing string.
Casinghead Price Per Unit Amount
The value per unit of measure of casinghead gas.
Cast Iron
An alloy of iron and about 2 to 4 percent carbon. (1) Grey cast iron: The graphite (carbon) is present as flakes. This makes a fracture appear grey.(2) White cast iron: The carbon is present as carbides. With no graphite to color it, a fracture appears metallic white.
Cast Lot Heat
Material originating from a final melt. For remelted alloys, a heat shall be defined as the raw material originating from a single remelted ingot.
Casting
(1) An object at or near finished shape obtained by solidification of a substance in a mold.(2) Pouring molten metal into a mold to produce an object of desired shape.
Catalog Item
A product offered by an organization.
Catalyst
A substance used to speed up or retard a chemical reaction without undergoing a chemical change itself during the reaction.
Catalytic Cracker
A large refinery vessel in which a foreign substance called a catalyst breaks down the hydrocarbon molecules while they are heated to a high temperature preparatory to their rearrangement into new and different molecules. When a particular oil is subjected to a certain temperature and pressure, a certain cracking takes place, making certain products. Also referred to as: cat cracker.
Catalytic Cracking
A cracking process that uses a catalyst to promote a chemical reaction that breaks up (cracks) the hydrocarbon molecules into smaller ones. Catalysts permit the use of less pressure to split the molecules and provide more control over the splits, allowing higher octane products. Two major kinds of catalytic cracking processes are fluid catalytic cracking and hydrocracking.
Catalytic Reforming
In the reforming process, catalysts are used to change the nature and shape of the molecules, producing ring like or branched molecules from straight ones. In other words, the molecules are rearranged, reformed, rather than split, as they are in the cat cracking process. Catalytic reforming is an upgrading process to raise the octane of heavy virgin naphtha and is the major process used to make high octane gasoline. Several chemical reactions occur during the reforming process, including: (1) The remova
Catastrophe Overhead Flag
An indicator of whether or not the contract provides for catastrophe overhead rates to reimburse the operator for additional overhead costs incurred during a catastrophe.
Catcher
A device employed to catch a scraping tool which has cleaned the pipe of foreign matter.
Cathead
One of the component drums or reels of the drilling rig draw works assembly which furnishes power, through the catline and jerk lines, to lift heavy objects, make up drill pipe joints, break out drill pipe joints, make up casing joints and similar operations.
Cathode
The negative terminal of an electrolytic cell. The portion of a corrosion cell which does not corrode. Reduction always occurs at cathode.
Cathode Ray Tube
A vacuum tube with a luminescent screen often used for viewing ultra sonic echo signals or for video readout of computer stored data. Commonly abbreviated as: CRT.
Cathodic Protection Insulator
A kit containing a plastic gasket and plastic bolt sleeves that is inserted between flanges for the purpose of stopping cathodic protection at that point.
Cathodic Protection Rectifier
A device for converting alternating current into direct current. Used to reduce corrosive action caused by reversing electric current flow in the soil.
Cation
The positively charged particle in the solution of an electrolyte which, under the influence of an electrical potential, moves toward the cathode or negative electrode.
Cation Exchange Capacity
A measure of the extent to which a substance will supply exchange cations. Also referred to as: Base exchange capacity.
Catline
A hoisting or pulling line operated from a cathead on a drilling or workover rig.
Cattleguard
A pipe or steel fabricated gateway that inhibits crossing by animals.
Catwalk
(1) A raised, narrow walkway between tanks or other installations.(2) The ramp to the side of the drilling rig where pipe is laid out to be lifted to the derrick floor by the catline.
Caustic
(1) The envelope representing the local convergence of rays of energy, e.g., light rays, acoustic rays, elastic rays, water waves.(2) Also referred to as Caustic Soda. SEE: Sodium Hydroxide.
Caustic Embrittlement
The intercrystalline cracking of metal due to accumulation of alkaline residue in a crevice.
Caustic Test
A test to determine the quantity of free sodium hydroxide in a caustic solution.
Caustic Unit
A system in which caustic is used to remove mercaptans and hydrogen sulfide from a liquid hydrocarbon stream, normally propane, LPG, or gasoline. The unit is regenerative if the caustic is continuously regenerated. It is batch if the caustic is periodically replaced without regeneration.
Cave In
Cave in is a severe form of sloughing.
Cavernous Formation
A formation having voluminous voids, usually the result of dissolving by formation waters which may or may not be still present.
Caving
Particles that fall from the wall of the borehole. Also referred to as: Sloughing.
Caving Proportion
That proportion of the sample which are interpreted to be cavings.
Cavitation
(1) The situation where the pressure in a liquid becomes lower than the hydrostatic pressure.(2) The collapse of bubbles in a fluid, caused by the static pressure being less than the fluid vapor pressure.
Cdp
SEE: Common Depth Point.
Cec
SEE: Cation Exchange Capacity.
Cellar
Excavation under the derrick to provide space for items of equipment at the top of the wellbore. Also serves as a pit to collect drainage of water and other fluids under the floor for subsequent disposal.
Cellar Deck
A deck located immediately below the main deck.
Cement
(1) The substance used to bond the casing in the borehole.(2) Sedimentology: Mineral material, usually chemically precipitated that occurs in the spaces among the individual grains of a consolidated sedimentary rock, thereby binding the grains together as a rigid, coherent mass; e.g., carbonate; calcite; illite.
Cement Accelerator
A chemical additive that speeds the setting time of cement.A material which accelerates or speeds up the normal rate of reaction between cement and water, resulting in an increase in the development of early strength, and, in some cases, a decrease in the setting time or thickening time.
Cement Addition
A material added to a cement clinker during manufacture, commonly gypsum/anhydrite and water.
Cement Additive Concentration Percentage
The percentage by weight of the additive contained in the cement.
Cement Additive Name
The trade name of the additive that is contained in the cement.
Cement Additive Type Code
An indicator of the type of additive used in the cement to perform a specific function in controlling cement properties; e.g., accelerator, retarder, weight reducer, filtration, water loss control.
Cement (api Classes)
Cement, API Classes A through J, meeting the applicable requirements of API Spec. 10.
Cement (astm Types)
Cement, types I through V, meeting the applicable requirements of Standard Specifications for Portland Cement ASTM C 150.
Cement Bond Index
The ratio of attenuation in zone of interest to attenuation in well cemented section. The computed bond index value is an indicator of the quality of cement bond.
Cement Bond Log
A well log of the vibrations of an ultrasonic acoustical signal as it passes through a four phase system of fluid, pipe, cement and rockof the borehole wall. If the pipe is not acoustically coupled tightly with a dampening material; e.g., cement, very little energy of the acoustical signal is lost. If the cement is bonded or acoustically coupled tight to the pipe, the energy is extremely dampened and the signal nearly disappears, thereby indicating that the casing is well cemented. The log may consist o
Cement Bond Log Run Flag
An indicator of whether a cement bond log was run.
Cement (calcium Aluminate)
The product obtained by pulverizing clinker which consists of hydraulic calcium aluminates formed by fusing or sintering a suitably proportioned mixture of aluminous and calcareous materials.
Cement Class Code
An indicator of an API cement class for well cements defined in API Specification 10.
Cement Column Length
The length of cement colum ; e.g., left inside the pipe, between the top and bottom of the cement, etc.
Cement (common, Regular Or Ordinary)
A cement intended for use under conditions not requiring moderate to high sulfate resistance. Corresponds to API Class A or Class C which are similar to ASTM Type I or Type III cements, respectively.
Cement (construction)
SEE: Cement (Common, Regular or Ordinary).
Cement Density
The specific gravity of a well cement as determined by a method similar to ASTM C 188: Test for Density of Hydraulic Cement. Most portland cements have a specific gravity of about 3.15 when tested by this method. Cement density should not be confused with slurry density.
Cement Displacement Fluid Type
The type of fluid used to displace cement during a cementing operation; e.g., water, brine, oil, mud.
Cement Evaluation Log
A cased wellbore cement evaluation log that displays data processed from ultrasonic transducers in such a way that channels in the cement sheath can be detected.
Cement Filler Material
A material added to a cement or cement slurry for the primary purpose of increasing the yield of the slurry.
Cement Fluid Characteristic
A description of any fluid used in a cementing stage.
Cement (gel)
A cement or cement slurry that has been modified by the addition of bentonite.
Cement (gypsum)
Composed primarily of the hemihydrate from of Calcium Sulfate (CASO4 1/2H2O). Plaster of Paris.
Cement (high Alumina)
SEE: Cement (Calcium Aluminate).
Cement (high Early)
(1) API Class C Cement,(2) ASTM Type III Cement.
Cement (high Temperature)
A cement designed to overcome strength retrogression within the temperature limits designated by the supplier.
Cement (hydraulic)
A cement that sets and hardens by chemical interaction with water and that is capable of doing so under water.
Cement Job Type
The type of cementing job being performed; e.g., casing, liner, plug, squeeze.
Cement Measured Top Depth
The measured depth to the top of cement inside the annulus between the casing and the wall of the wellbore. This is often determined by readings on a cement record log or may be calculated/estimated by volumes pumped when casing is originally cemented.
Cement (modified)
A cement whose properties, chemical or physical, have been altered by additives. This refers to specific formulations of gel cement containing certain concentrations of dispersing agent.
Cement (neat)
A cement paste or slurry containing no additives.
Cement (ordinary)
SEE: Cement (Common, Ordinary or Regular).
Cement Plan
Proposed cementing required for setting proposed casing strings.
Cement Plug
A portion of cement placed at some point in the wellbore to affect a sealing action.
Cement (portland)
Hydraulic cement produced by pulverizing clinkers consisting essentially of hydraulic calcium silicates and usually containing one or more of the forms of calcium sulfate as an interground addition.
Cement (portland Blast Furnace Slag)
An intimate and uniform blend of portland cement (or clinker) and fine granulated blast furnace slag in which the slag is within specified limits.
Cement (portland Pozzolan)
A hydraulic cement consisting of an intimate and uniform blend of portland cement or portland blast furnace slag and fine pozzolan produced: (1) by intergrinding portland cement clinker and pozzolan;(2) by blending portland cement or portland blast furnace slag cement and finely divided pozzolan;(3) or a combination of intergrinding and blending, in which the amount of the pozzolan constituent is within specified limits.
Cement Pump Pressure Measurement
The pump pressure required to displace fluid down the wellbore during the entire cementing operation; e.g., rig pump pressure, cement truck pump pressure.
Cement Quantity
The quantity of cement used for casing, plugging or performing a squeeze job.
Cement Rate
The flow rate of the cement entering or leaving the wellbore, measured with a flow sensor.
Cement (regular)
SEE: Cement (Common, Ordinary or Regular).
Cement (retarded)
A cement in which the thickening time is extended by adding a chemical retarder.
Cement Retarder
A chemical which is added to cements or slurries to lengthen thickening time.
Cement Return Flow Percentage
The percentage of return flow during the cementing operation.
Cement Return Volume
The cumulative volume of cement returned to the surface during cementing. Does not include mud circulation prior to job.
Cement Sand Content
In cementing work, the term refers to the weight of sand blended with dry cement powder. The sand content is expressed as percent by weight of cement or as pounds of sand per sack of cement.
Cement (slag)
SEE: Cement (Granulated Blast Furnace Slag).
Cement (slow Set)
A cement in which the thickening time is extended by: (1) Eliminating the rapid hydrating components in its composition. (2) By adding a chemical retarder. API classes D, E and F are slow set cements.
Cement Slurry
The liquid state of the cementing material after water has been added. After it has set to a solid, it is called cement.
Cement Slurry Density
The weight per unit volume of the cement slurry used in the primary cementing job.
Cement Slurry Occurrence Count
The stage number of slurry in the cementing process; e.g., 1, 2. etc.
Cement Slurry Volume
The sum of the absolute volumes of solids and liquids that constitute a slurry.
Cement Slurry Water Percentage
The water content of a cement slurry expressed as parts of water per 100 parts of dry cement by weight. Per cent usually refers to per cent by weight. If per cent by volume is meant, it should be so stated.
Cement Slurry Yield
The volume of cement slurry in cubic feet that is obtained from a sack of cement.
Cement (sulfate Resistant)
Cements which meet applicable requirements of API Spec 10.
Cement System
The combination of materials which make up well cement formulations.
Cement Temperature
Measured temperature of the cement entering or leaving the wellbore.
Cement Thickening Time
The time required for a cement slurry of a given composition to reach a consistency of 100 Bearden units of consistency (Be).
Cement To Surface Flag
An indicator of whether cement was circulated to ground surface or bottom of the cellar outside the casing.
Cement Top Behind Casing Depth
SEE: Cement Measured Top Depth.
Cement Types (astm)
SEE: Cement Classes (API).
Cement (weighted)
A cement slurry containing additives to increase its normal density.
Cement (well)
A cement or mixture of cement with other materials that is intended for use in oil, gas, geothermal or water wells.
Cementation
Sedimentary: The process that deposits chemical precipitate out of water to form bridges between the grains, solidifying the rock.
Cementer Authorized Person's Title
The job title of the Cementer's Authorized person.
Cementer Certification Date
The date a document test, etc. is certified as correct by the Cementer.
Cementing
The operation by which cement slurry is forced down through the casing and out at the lower end in such a way that it fills the space between the casing and the sides of the borehole to a predetermined height above the wellbore bottomhole. This activity is for the purpose of securing the casing in place and preventing water and other fluids from entering the borehole from the surrounding rock.
Cementing Date
The date the cementing operation was performed.
Cementing Displacement Pressure Measurement
The pressure at which the cement slurry is pumped into the borehole.
Cementing Displacement Rate
The volumetric flow rate at which the cement slurry is pumped into the borehole.
Cementing Time
The total elapsed time for a cementing operation from the beginning of mixing until the completion of displacement to final depth and complete circulation of any excess slurry to the surface.
Center
The center of the smallest circle circumscribing a defined area. For regular geometric shapes; e.g., rectangles; triangles; this corresponds to the intuitive location of the center.
Center Pin
Vertical pin or shaft which acts as rotation centering device and connects revolving upperstructure and base mounting. Also referred to as: King Pin.
Center Post
A tubular member which acts as the centerline of rotation and as the connective member to the platform. Also referred to as: King Post.
Central Conductor
A conductor that is passed through the pipe, for the purpose of creating a circular or circumferential magnetic field in the pipe. This term does not imply that the current rod must be centered in the pipe. Also referred to as: Shooting Rod.
Central Facility
Installation serving two or more leases, providing one or more of such functions as separation, compression, dehydration, treating, gathering, or delivery.
Central Meridian
(1) A longitude passing through the center of a projection. It is generally a straight line about which the projection is centered (symmetrical). Usually the central meridian defines the x-origin of the map.(2) The meridian on a graticule that is the axis of symmetry for the geometric properties of the graticule as displayed on a map projection.
Centralizer
Guides which are attached to casing and which serve to keep it centered in the borehole.
Centralizer Count
The number of centralizers used on a casing string.
Centralizer Logging Tool
A device which positions the logging tool in the center or near center of the borehole, aligned with the borehole axis.
Centrate
Clarified liquid discharged from a centrifuge.
Centrifugal Force
Force tending to pull outwardly on a body when it is rotating around a center.
Centrifugal Separator
A general term applicable to any device using centrifugal force to shorten and/or to control the settling time required to separate a heavier mass from a lighter mass.
Centrifugal Separator Retention Time
The time the liquid phase is actually in the separating device.
Centrifuge
A machine using centrifugal force for separating substances of different densities.
Centrifuge Port
The opening in a centrifuge for entry or exit of materials. Usually applied in connection with a descriptive term; e.g., feed ports; overflow ports.
Centripetal Force
That force which tends to propel matter inward.
Certificate
A certificate of public convenience and necessity issued under the Natural Gas Act, 1938, as amended.
Certificate Of Fiscal Responsibility Number
The number of a certificate of fiscal responsibility (COFR) issued by a regulatory agency to certify that the lessee has a minimum amount of liability insurance.
Certificated Natural Gas
Any natural gas which has a certificate issued and in effect, transported by any interstate pipeline.
Certification
Written notification of pricing basis under regulations.
Certification Date
The date a document, test, etc. is certified as correct.
Chain Hoist Beam
A section of steel I-beam or other structural steel which supports and allows a chain hoist to be moved from one portion of a building to another.
Chain Tongs
A tool used in assembling or disassembling pipe or pipe fittings, having a lever with a serrated end, provided with a chain, to either turn pipe or hold it from turning.
Chamber Lift
A special type of intermittent gas lift which uses the tubing casing annulus or a bottle on the end of the tubing string for the accumulation of formation liquids between cycles.
Chamber Vessel
A vessel which measures by volume.
Change Of Address Flag
An indicator of whether the reporter's mailing address has changed.
Channel
A single series of interconnected devices through which data can flow from source to recorder. A recording device that is N-channel will allow the simultaneous recording of N groups of geophones.
Channeling
Ordinarily refers to bypassing of reservoir oil by gas or water. Also refers to bypassing of mud by cement during cementing operations. An undesirable flow condition existing when a fluid bypasses portions of a packed vessel or bubble tray due to improper packing or poor liquid distribution.
Charge
An explosive material, used as a seismic source.
Charles Law
The volume of a given weight of gas varies directly as its absolute temperature, provided the pressure remains constant.
Chart Integrator
A mechanical or optical device employed to calculate the cumulative or total flow recorded on a flow meter chart.
Chase Thread
To straighten and clean threads of any kind.
Chatter
(1) A noisy indication that a mechanical part, pipe, valve, etc. is behaving erratically and/or destructively.(2) A wavy surface of the thread flank, root, crest, or chamfer, produced by a vibrating cutter insert.
Check Valve
A valve that permits flow in one direction only, by automatically closing when the fluid attempts to flow in the reverse direction.
Checklist Id Code
An indicator of what the checklist record money represents; e.g., tax exemption, state withholding, Federal code computation code withholding, Regular interest (will accrue gross amount paid for owner), Qualified goverernmental interest, Qualified charitable interest, Exempt Indian oil (tribal).
Checkshot Survey
A survey to determine formation seismic wave velocities over specified depth intervals by measuring time from a surface energy source to a geophone located at different depths within a wellbore.
Chemical
In drilling fluid terminology, a chemical is any material that produces changes in the viscosity, yield point, gel strength, and fluid loss, as well as surface tension.
Chemical Barrel
A container in which various chemicals are mixed prior to addition to the drilling fluid.
Chemical Feeder
A small-volume pump used to inject chemicals.
Chemical Oxygen Demand
A measure of the amount of oxygen required to oxidize organic and oxidizable inorganic compounds in water. The COD test, like the BOD test, is used to determine the degree of pollution in an effluent. Commonly abbreviated as: COD.
Chemistry
The science dealing with the nature and composition of substances and of the reactions which cause substances to break down or combine to form other substances.
Chemotaxis
The orientation or movement of a living organism in response to chemical agents.
Chiller
A heat exchanger employed to cool a process stream, such as absorption oil or rich gas, with brine or refrigerant.
Chimney Tray
A circular metal plate, with a large chimney in the center, such as used in a bubble tower or packed column, to collect liquid without preventing upward flow of vapor from below.
Chisel Tongs
Pipe tongs that grip the pipe with a chisel like insert in the jaw of the wrench.
Chloride Concentration
The concentration of chlorides in water analysis.
Chloride Stress Cracking
The stress corrosion cracking of ferrous based alloy steels, which may result when exposed to wellstreams containing water and chlorides under certain conditions of concentration and temperature. Other constituents present, such as oxygen, may contribute to chloride stress cracking.
Chloride Stress Cracking Service
Process streams which contain water and chlorides under conditions of concentration and temperature high enough to induce stress cracking of ferrous base alloy materials. Other constituents present, such as oxygen (O2), may contribute to such chloride stress cracking.
Chloride Test
The Mohr test for determination of soluble chlorides in water by titration with a standard silver nitrate solution in the presence of potassium chromate indicator. Results of the chloride test are used to evaluate and control blowdown and to calculate makeup in boilers and cooling systems.
Chlorinator
A device for injecting chemicals into a well or process.
Chlorine Log
A well log based on the counting rate of capture gamma rays produced by capture of thermal neutrons by chlorine in the rocks surrounding the borehole. The interpretation of such curves yields a calculated water saturation.
Chock
Block or wedge used beneath a length of pipe so that it cannot roll.
Choke
A type of orifice installed in a line to restrict flow and control the rate of production. Surface chokes are a part of the Christmas tree and contain a choke nipple, or bean, with a small diameter bore (an orifice) that serves to restrict the flow. Also, chokes are used to control the rate of flow of the drilling fluid out of the wellbore when the wellbore is shut in with the blowout preventer and a kick is being circulated out of the wellbore.
Choke Bean
SEE: Flow Bean.
Choke Line
An extension of pipe from the blowout preventer assembly, used to direct wellbore fluids from the annulus to the choke manifold.
Choke Line Joint Percentage
The proportion of the total choke line which is made up of joints, expressed as a percentage.
Choke Line Joint Size
The internal diameter of the joints in the choke line.
Choke Line Length
The total length of the choke line.
Choke Line Size
The internal diameter of the choke line.
Choke Line Valve
The valve(s) connected to and a part of the blowout preventer stack that controls the flow to the choke manifold.
Choke Manifold
An assembly of valves, chokes, gauges, and lines used to control the rate of flow from the well completion when the blowout preventers are closed.
Choke Size
The inside diameter of the choke orifice.
Christmas Tree
The valves and fittings assembled above the tubing head at the wellbore origin to control the flow of hydrocarbons and other fluids from a completed well. The Christmas Tree is attached to the top of the tubing head, and may consist of the tubing head flange, the bottom most master valve, the crown or swabbing valve, the wellhead choke and all valves and fittings in between.
Chromate
A compound in which chromium has a valence of 6; e.g., sodium bichromate. Chromate may be added to drilling fluids either directly or as a constituent of chrome lignites or chrome lignosulfonates. In certain areas, chromate is widely used as an anodic corrosion inhibitor, often in conjunction with lime.
Chromatograph Analyzer
An analytical instrument that separates mixtures of substances into identifiable components by allowing them to seep through an absorbent so that each compound becomes absorbed in separate layers.
Chromatograph Sample Depth
Measured depth corresponding to the chromatograph cycle sample while circulating.
Chromatograph Test
A laboratory analysis of a gas sample to determine composition of the gas. The analysis will determine the mole percent of each component of the gas which can be used to calculate liquid volume percents, Gallons per thousand cubic feet (GPM), British thermal units (BTU), and gravity.
Chrome Lignite
Mined lignite, usually leonardite, to which chromate has been added. The lignite can also be treated with either sodium or potassium hydroxide.
Chronic Bioassay
A test involving a substantial portion of the life span of a fish or other organisms.
Chronological Zone Code
Indicates the maximum flooding surface within a depositional sequence (Regional stratigraphy marker).
Chronostratigraphic Unit
A classification of a geologic body based on chronostratigraphy.
Chronostratigraphy
The branch of Stratigraphy dealing with the age of rock strata and their time relationships. Also referred to as: time rock stratigraphy.
Chronozone Net Sand Thickness Value
The net sand thickness for a stratigraphic marker.
Chronozone Sand Percentage
The percentage of sand contained in the chronozone.
Chronozone True Vertical Depth
The subsea depth to the top of the chronozone.
Circular Arc Method
Uses both sets of measured angles associated with each course length to recreate the wellbore path geometry as a sequence of small circular arcs constrained by the measured angles to pass through the end points with inclination and direction angles as measured.
Circular Magnetic Field
The magnetic field in or surrounding a current carrying conductor pipe, or pipe with an interior current carrying rod. Also referred to as: Circumferential Magnetic Field.
Circular Magnetization
The production of a magnetic field in a pipe wall or coupling such that the magnetic field is oriented circumferentially. Also referred to as: Circumferential Magnetization.
Circulating Pressure Measurement
The pressure required to circulate a fluid at a given rate and at a specified depth.
Circulation
The process of cycling drilling fluid through pipe and wellbore while drilling operations are temporarily suspended. This is done to condition the drilling fluid and the borehole walls before hoisting the drill pipe and to obtain cuttings from the wellbore bottomhole before drilling proceeds. Circulation of the drilling fluid while drilling is suspended is usually necessary to prevent drill pipe from becoming stuck while being retracted.
Circulation Device
A flow control device; e.g., a sliding sleeve or side pocket mandrel which is run on production/injection tubing for the purpose of establishing communication between tubing and the tubing annulus.
Circulation Duration
Duration of drilling fluid circulation.
Circulation Rate
The rate of air, gas, or foam being circulated as drilling fluid.
Circulation Stopped Date
Date that circulation of the drilling fluid was stopped.
Circumferential Magnetization
SEE: Circular Magnetization.
City Block
Identifies a geographic area within a city subdivision.
City Gate
Delivery point of gas to a local distribution company's system inlet.
City Location
The city location is composed of the subdivision, block, and city lot.
City Lot
Identifies a geographic area within a city block.
City Name
The legally recognized name of a city.
City Subdivision
The city location is composed of the subdivision, block, and city lot.
Cladding
A process for covering one metal with a thinner sheet of another to obtain increased corrosion resistance or other desirable properties of the thinner.
Clamp Connection
A pressure sealing device used to join two items without using conventional bolted flange joints. The two items to be sealed are prepared with clamp hubs. These hubs are held together by a clamp containing two to four bolts.
Class I Location
A National Electrical Code (NEC) Class I location is one in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures.
Classifier
SEE: Coalescer.
Clay Classification
The classification of clays, based on size, using the Wentworth Scale. Particles have a diameter of less than 1/256 millimeters.
Clay Extender
(1) An agent which has been added to clay to increase its initial yield. Peptization usually refers to the addition of an electrolyte to increase the initial yield; i.e., soda ash.(2) A newer term, beneficiation, generally applies to the addition of organic compounds; e.g., polyacrylamide.
Clay Mineral
A plastic, soft, variously colored earth, commonly a hydrous silicate of alumina, formed by the decomposition of feldspar and other aluminum silicates. Clay minerals are essentially insoluble in water but disperse under hydration, shearing forces such as grinding, velocity effects, etc., into the extremely small particles varying from submicron to 100 micron sizes.
Clay Solid
SEE: Colloidal Solid.
Clean Out
To remove sand, scale, and other deposits from the well completion to restore or increase production.
Clean Sand
Sand that is well sorted, having a narrow range of particle sizes, and less than 10%-15% clay content.
Cleanout Plate
An opening in a tank or other vessel through which sediment may be removed.
Clearance
(1) Space between the outer diameter of the downhole tool and the wall of the borehole; the difference in the diameter of the borehole and the tool.
Clearance Pocket
A fixed or variable volume device on a reciprocating compressor cylinder. It is used to change the capacity of the cylinder.
Client
SEE: Business Associate.
Clinograph
An instrument to measure and record inclination.
Clip
A U-bolt or similar device used to fasten parts of a wire cable together.
Close In
(1) SEE: Shut In.(2) To close the blowout preventers on a wellbore that is being drilled or worked over in order to control a kick.
Close Nipple
A very short piece of pipe having threads over its entire length.
Closed Fracture Count
The number of closed fractures counted in a depth interval.
Closed In
A well capable of producing oil or gas, but temporarily shut in.
Closed In Bottomhole Pressure
SEE: Shut In Bottomhole Pressure.
Closed In Pressure
SEE: Shut in Formation Pressure.
Closed Traverse
Term used to indicate the closeness or repeatability of two surveys, one survey going in the wellbore and the second survey coming out of the wellbore.
Closed Water Treating System
A system of treating water in which the water does not come in contact with air.
Closing Ratio
The ratio of the wellhead pressure to the pressure required to close the blowout preventer.
Closure
The vertical distance between the anticlinal crest and the highest point at the base of the fold. Also referred to as: Line of Closure.
Cloth
SEE: Screen Cloth.
Cloud Point
The temperature at which fluid begins to congeal and becomes cloudy.
Clutch
A piece of equipment for the engagement or disengagement of power.
Cmp
SEE: Common Midpoint.
Co2 Content
SEE: Carbon Dioxide Content.
Coagulant
(1) That agent which produces clotting; i.e., to change from a fluid into a thickened mass.(2) To curdle, congeal, or clot.
Coagulation
The joining together of finely divided particles of matter suspended in water, forming a mass large enough to settle out of suspension. Chemicals such as lime or alum are often used to induce the clumping of particles in order to settle out impurities. In drilling fluid terminology, it is a synonym for flocculation.
Coal Oil
(1) Illuminating and heating oil obtained from the destructive distillation of bituminous coal.(2) Kerosene made from distilling crude oil.
Coalescence
The change from a liquid to a thickened curdlike state by chemical reaction. Also, the combination of globules in an emulsion caused by molecular attraction of the surfaces.
Coalescer
(1) An agent which helps materials unite into one body or mass.
Coastal Zone
Coastal waters and the adjacent lands that exert a measurable influence on the uses of the sea and its ecology.
Coastline
The line of ordinary low water along that portion of the coast which is in direct contact with the open sea or the line marking the seaward limit of inland waters.
Coat And Wrap
To cover pipe with bituminous, or similar material, and textiles for protection against corrosion.
Coating
(1) A film as applied to the substrate.(2) A condition wherein undersize particles cover the apertures of the screening surface by virtue of stickiness.
Coating Material
The liquid material prior to application on the substrate.
Cobalt Bromide Tester
The laboratory apparatus for determining the dryness of commercial propane by observing the color variation of cobalt bromide when contacted with the vapors at 32 degrees Fahrenheit and 50 psig.
Cobble
A clastic sedimentary particle with a diameter between 64 and 256 millimeters, based on the Wentworth Scale of Measurement.
Coefficient Of Thermal Expansion
SEE: Thermal Expansion CoeffiThe change in length of a material as a function of its total length due to a change in temperature.
Cohesion
The attractive force between the same kind of molecules; i.e., the force which holds the molecules of a substance together.
Coil
A compact section of pipe or tubing used for cooling or heating either the fluid in the pipe or the material surrounding it.
Coil Area
The coil area is the heat transfer area and is normally calculated using the outside surface area of the pipe.
Coil Method
A method of magnetization in which pipe is encircled by a current carrying coil.
Coil Shot
A short pulse of magnetizing current passed through a coil surrounding a pipe for the purpose of longitudinal magnetization.
Cold Weld
A metallurgically inexact term generally indicating a lack of adequate weld bonding strength of the abutting edges, due to insufficient heat and/or pressure.
Collar
A coupling device used to join two lengths of pipe. A combination collar is a coupling with left hand threads in one end and right hand threads in the other. Sometimes drill collars are called simply collars.
Collar Locator
A well logging device that detects casing or tubing collars for depth orrelation purposes. It may be operated mechanically or electrically to produce a log showing the location of each casing collar or coupling in a wellbore. When properly interpreted, this well log provides an accurate way to measure depths in a wellbore.
Collateral Coverage Type Code
Indicates the type of coverage a collateral provides.
Collector Pipe
A perforated or slotted pipe near the top of the coalescing section in a treater to remove the treated oil as uniformly as possible through this portion of the treater.
Colloid
A state of subdivision of matter which consists either of single large molecules or of aggregations of smaller molecules dispersed to such a degree that the surface forces become an important factor in determining its properties. The size and electrical charge of the particles determine the different phenomena observed with colloids; e.g., Brownian movement. The sizes of colloids range from 1 x 10-7 cm to 5 x 10-5 cm (0.001 to 0.5 microns) in diameter, although the particle size of certain emulsoids can
Colloidal
Pertaining to suspended solids so finely divided that they will not settle.
Colloidal Composition
A suspension containing one or more colloidal constituents.
Colloidal Solid
A clay having unusual properties; e.g., plasticity; thixotropy; swelling; a solid particle of less than two micron equivalent sperical diameter.
Colloidal Suspension
A stable, homogenous system of very fine particles of matter dispersed uniformly throughout a liquid medium, having properties which differ both from a true solution and from a suspension of larger particles. True colloidal suspensions have particle size range of 5 to 200 micrometers.
Color
A property of a sediment represented by the hue caused by combinations of colors of the particles, surface coating, matrix and cement, and controlled in part by the degree of fineness of the particles; e.g., white, light brown, black.
Color Bodies
Those complex molecules which impart color (usually undesirable) to a solution.
Color Code
Paint band identification of pipe classification in accordance with appropriate specifications.
Color Unit
Measure of the intensity of coloration of water using a platinum cobalt standard.
Column
A tall vertical processing vessel; e.g., fractionator, absorber.
Columnar Oriented Ice
Columnar grained ice with c-axis orientation in a preferred horizontal direction.
Columnar Random Ice
Columnar grained ice with c-axis orientation in a random horizontal direction.
Combination Gas Metal Arc Weld And Submerged Arc Weld Pipe Pipe Having One Longitudinal Seam Formed By The Combination Of Continuous Gas Metal Arc Welding And Automatic Submerged Arc Welding. The Gas Metal Arc Welding Process Shall Be First And Followed By The Submerged Arc Welding Process.
Combination Trap
A reservoir trap having characteristics of both structural and stratigraphic traps in approximately equal proportions.
Combined Fixed Rate Or Percentage Basis
SEE: Combined Rate.
Combined Method
SEE: Borehole Survey Calculation Method (Refer to Mercury Method).
Combined Rate
A rate provided by the accumulation of all charges considered includable in district expense, administrative overhead, and the operator's warehouse operating and maintenance expense. This rate may be stated in dollars or as a percent of specific costs. Also known as: Combined Fixed Rate or Percentage Basis.
Combustible
Capable of burning.
Combustible Liquid
A liquid having a flash point at or above 100 F (37.8 C). Combustible Liquids are subdivided as follows: Class II Liquid: Those having flash points at or above 100 F (37.8 C) and below 140 F (60 C). Class IIIA Liquid: Those having flash points at or above 140 F (60 C) and below 200 F (93 C). Class IIIB Liquid: Those having flash points at or above 200 F (93 C).
Combustion
The chemical reaction of rapid oxidation which is accompanied by the emission of light and heat (the flame). Combustion begins when the temperature of the ignitible substance reaches its apparent ignition temperature. This process will be self sustaining as long as the heat released in combustion maintains the temperature within the flammable range of the ignitible substance.
Come Along
A stretching or tightening device that crawls along a length of chain.
Come Out Of The Hole
To pull drill pipe, tubing, wireline tools, etc., out of the wellbore.
Commercial Elevation
The distance to a particular point on the drilling rig which is above or below the reference datum as reported by a commercial elevation company.
Commercial Elevation Source
The companies which are the source that provided the commercial elevation; e.g., Abilene, Powers, Laughlin & Simmons.
Commercial Ground Elevation
The ground level elevation of a wellbore origin of the well as measured and reported by a commercial elevation company.
Commercial Well
A well which produces reserves in sufficient quantities to be expected to be economical for commercial operation; i.e., one in which the revenues are higher than the costs of operating and maintaining the well.
Commingle
Mixing fluids from more than one source to make a single fluid stream.
Commingled Gas
Gas from two or more sources which is combined in a single stream.
Commingling
The act of mixing fluids from more than one source to make a single fluid stream.
Commingling Facility
An installation, serving two or more leases, which provides services such as gathering, separating, treating, and storing more economically than could several smaller facilities.
Commingling Permit
A regulatory agency's permission for an operator to perform commingling.
Commingling Permit Number
An identifier of the leases and facilities involved in commingled production arrangements with the regulatory numbers issued by certain state regulatory agencies or tax commissions. These numbers are primarily for the purpose of enabling the states to associate data furnished on production and/or tax reports with the leases or horizons being commingled.
Commingling Test Requirement Flag
An indicator of whether a comingling test is required for the well.
Commingling Type Code
An indicator of where production is commingled; e.g., downhole, surface, multiple zones not commingled, etc.
Common Depth Point
Seismic traces that have a nonzero offset can be grouped into gathers that have the same reflection point at depth. In the case of layered media with no dip, the common depth point (CDP) is directly below the midpoint of the source and receiver. Hence, a CDP gather is identical to a common midpoint (CMP) gather. When dip is present, CMP gather no longer shares a common depth point. Special processing is required in order to create traces that do share common depth points at all times. Commonly abbreviat
Common Midpoint
(1) The portion of the subsurface which is midway between a seismic source and a receiver.(2) Having the same or nearly the same midpoint between a seismic source and receiver. The meaning of nearly is an algorithmic question. The process of binning assigns common midpoint (CMP) traces to a bin node.
Communication Contact Telephone Number
The telephone number of the communication contact.
Company Acreage
Any acreage in which the indicated company owns a direct interest, including working interests, fee lands, mineral interests, payments out of production, and royalty and overriding royalty interests. This includes both company and outside operated properties.
Company Assigned Well Code
The unique identifier, assigned by the company, to identify a particular completion.
Company Leased Acreage
The indicated company's net acreage leased in producing working interest properties.
Company Owned Acreage
The indicated company's net acreage owned in producing working interest properties.
Compensated Acceleration Method
SEE: Borehole Survey Calculation Method (Refer to Mercury Method).
Compensated Formation Density Log
A dual spacing formation density log. The compensated formation density logging device employs two receivers spaced at different distances from the source, thus allowing compensation for mud and mud cake effects.
Compensated Neutron Log
A well log made with a neutron logging tool having two neutron detectors to reduce borehole effects. The neutron porosity is derived from the ratio of the counting rates of the two detectors.
Compensatory Royalty
Payments to royalty owners as compensation for losses in income which they may be suffering due to failure to adequately develop a lease.
Competitive Reservoir
A reservoir in which there are one or more well completions in a single reservoir encompassed by two or more leases from which the lessees plan future production.
Completion Cost
Monies expended in preparing a well for the taking of production up to and including the initial installation of tubing and the wellhead in and on a well but does not include equipping costs.
Completion Date
SEE: Well Completion Date.
Completion Identification
The identifier for a specific well completion.
Completion Location
Under the Natural Gas Policy Act (NGPA), 1978, as amended, any subsurface location from which natural gas is being, or has been, produced in commercial quantities. When this term is used in reference to any marker well, it means any subsurface location which has had natural gas produced from the location in commercial quantities after January 1, 1970 and before April 20, 1977.
Completion String
SEE: Producing String.
Completion Type Code
SEE: Well Completion Type Code.
Complex
A grouping of two or more man made offshore structures connected by walkways.
Complex Identifification Number
The unique identifier assigned to a single man-made structure or a group of structures connected by a walkway.
Composite Log
Several well logs of the same or similar types, usually from different logging runs, which have been spliced together to form a single countinuous record from the shallowest to the deepest log reading along a wellbore path.
Composite Sample
A fluid containing all elements (components) originally present in fluid at point of origin; i.e., downhole sample containing water, oil and gas.
Composition Pipe
A pipe that is porous in nature and made of components such as cement, clay, fibers, ethylene, and asbestos.
Compressibility
The change in specific volume and density of a sample under hydrostatic pressure.
Compressibility Factor
SEE: Z-Factor.
Compressibility Factor Pressure Measurement
The pressure at which the compressibility factor was measured.
Compressibility Factor Temperature
The temperature at which the compressibility factor was measured.
Compression
Act of compressing, or state of being pressed together to make more compact. In the sense of being the opposite of tension.
Compression Adjustment
The adjustment to make to theoretical residue volumes for compression calculations.
Compression Deduction Value
The value used to adjust the base residue rate for compression of gas in a gas system.
Compression Range
Identifies the method of calculating the compression deduction to residue price.
Compression Ridge
First year ridge formed primarily by buckling, bending, or local crushing of colliding ice sheets caused by relative motion in the direction perpendicular to their common boundary. Generally composed of loosely stacked angular ice blocks, the ridge tends to be a curvilinear feature with a weaving pattern established by the extent of finger rafting.
Compression Stage Adjustment Flag
An indicator of whether or not the settlement should be adjusted for the number of stages used in compressing the gas stream.
Compressional Wave
Waves in which the particle motion or vibration is in the same direction as the propagated wave (longitudinal wave).
Compressive Strength
The degree of resistance of a material to force acting along one of the axis in a manner tending to crush it.
Compressor
A rotating or reciprocating machine, together with its driver and associated scrubbers, coolers, pipe, valves, controls, etc., used to compress gas or air from a lower to a higher pressure.
Compressor Bottle
A coded, customized, fabricated vessel attaching the pipe to compressor cylinders by means of flange or threads. Has value in reducing vibration or pulsation and improves flow characteristics of the medium being compressed.
Compressor Cylinder
Chamber in a compressor containing the piston, liner, compressor valves and chairs.
Compressor Station Cost
Costs of acquiring and installing compressor buildings and equipment, including auxiliaries, foundations, guard rails, enclosures, and other items incidental to compressor operations.
Computed Gravity
The computed gravity at a point on the surface.
Computed Magnetics
The computed magnetics at a point on the surface.
Computer Production Control
An operation wherein field conditions and activities are monitored and/or controlled automatically by a computer system; i.e., well testing; lease production; equipment operational and safety status. Commonly abbreviated as: CPC.
Concentration Cell
(1) Metal ion: A corrosion cell in which a potential difference is produced by a difference in concentration of metal ions.(2) Oxygen: A corrosion cell in which a potential difference is produced by differences in oxygen concentration. Region of low oxygen concentration is the anode or corroding area.
Concentric Control System
A system utilizing a concentric tubular arrangement to transmit control signals to the surface controlled subsurface safety valve (SCSSV).
Concentric Operation
A well operation conducted using small diameter tubing inside conventional tubing or tubingless completions, normally with the Christmas Tree in place and using a small rig or hoisting unit.
Concession
An area of interest and subsurface volume identified by a concession agreement.
Concession Agreement
An agreement (usually from a host government) permitting a foreign petroleum company to prospect for and produce minerals in the area subject to the agreement. The terms ordinarilly include a time limitation and a provision for royalty to be paid to the government.
Concession Block Number
A number that uniquely identifies a block relating to a concession. The relationship of a concession to a block is very arbitrary depending on the government and the circumstances involved. The boundaries of a concession can fall within a single block, consist of the entire block, or fall within multiple blocks.
Concession Number
An unique identifier of a concession.
Condensate
Liquid hydrocarbons produced with natural gas that are separated from the gas by cooling and various other means. Condensate generally has an API gravity of 50 degrees to 120 degrees and is water white, straw, or bluish in color. It is the liquid recovery from a well classified as a gas well. It is generally in the gaseous state under reservoir conditions but becomes liquid either in passing up the hole or at the surface. These hydrocarbons, from associated and nonassociated gas well gas, normally are r
Condensate Beginning Inventory Volume
The measured or calculated quantity of condensate in storage facilities at the beginning of a specified period.
Condensate Ending Inventory Volume
The measured or calculated quantity of condensate in storage facilities at the end of a specified period.
Condensate Gas Ratio
The ratio of condensate produced to a unit volume of gas.
Condensate Net Taxable Amount
The value of condensate on which tax is based.
Condensate Production Volume
The volume of condensate produced for a specified period.
Condensate Reported As Oil Volume
The volume of condensate reported as oil.
Condenser
(1) An electrical device that, when wired in the line of an electrical circuit, stores a charge of elecricity and returns the charge to the line when certain electrical conditions occur. (2) A heat exchanger employing air or water to partially or completely liquify a vapor stream.
Conductance Bridge
An instrument, similar to a wheatstone bridge, used to estimate the dissolved solids content of water by measuring the specific electrical conductance of the solution.
Conductivity
A measure of the quantity of electricity transferred across a unit area per unit potential gradient per unit time. It is the reciprocal of resistivity.
Conductor Pipe
A relatively short string of large diameter pipe which is set to keep the top of the wellbore open and to provide means of conveying the upflowing drilling fluid from the wellbore to the surface drilling fluid system until surface casing string is set in the well. Conductor pipe may also be used in well control. Conductor pipe is usually cemented.
Conduit Seal
A sealing fitting poured with cement like potting compound designed to contain an explosion in the enclosure to which it is attached.
Cone
SEE: Hydrocyclone.
Confidentiality Expiration Date
1. An indicator of the status of the release of privately owned information and data that are not available for public review or distribution to the public, as specified by law, regulation, order, or policy. Regulatory agencies define such data as proprietary data; e.g., electric logs, core descriptions and analysis, seismic record section, geological, geophysical, engineering information, maps; reports, correspondence, based on or containing information furnished by industry sources to the agencylc in co
Configured Flow Area
The effective flow area of a restricted portion of a drill string.
Confining Pressure Measurement
An equal, surrounding pressure.
Confirmed Nomination
An agreement by a seller to deliver/cause delivery or a transporter to receive and deliver a specifiic quantity of gas for a specified period at various points under a sales or transportation agreement or for all contracts at one specific point. The confirmed nomination is in response to a purchaser's or shipper's nomination.
Conformance
Compliance with specified requirements.
Congressional Range
North-south tier of townships identified by its relation to a principal meridian.
Congressional Survey
A location survey dividing the map into ranges and townships usually of 6 mile dimensions and numbered and referenced to standard survey base and meridian lines.
Congressional Township
A quadrangle approximately 6 miles on a side with boundaries conforming to meridians and parallels. It is further subdivided into 36 sections, each approximately one mile square, an east-west tier identified by its relation to a principle meridian.
Coning
(1) A reservoir effect usually associated with high producing rates. In the case of water, the bottom water is attracted upward when the pressure differential over the producing zone is increased beyond the critical limits. In the case of gas, the gas is attracted downward by the same phenomena.(2) A condition, detrimental to good vapor-liquid contact, existing when vapor velocity through bubble cap slots is excessive and gas pushes the liquid away from the slots.
Connate Water
Fossil sea water trapped within sediments during deposition.
Connection
The joining of two lengths of pipe.
Connector
(1) Riser devices used to latch and unlatch risers and lower marine riser packages to subsea equipment.(2) Tendon devices used to latch and unlatch tendons to the foundation system and to connect the tendon to the platform.
Conodont Alteration Index
The degree of thermal maturity as measured by the color of specimens of conodonts, fossils found in rocks of combrian to triassic age. Also known as conodont color index.
Conodont Color Index
SEE: Conodont Alteration Index.
Consenting Owner
A working interest owner who elects to participate in a project or operation.
Conservative Pollutant
A pollutant that is relatively persistent and quite resistant to degradation, such as parachlorobiphenyls.
Consistency
(1) A rheological property of matter which is related to the cohesion of the individual particles of a given material, its ability to deform, and its resistance to flow. The consistency of cement slurries is determined in accordance with required standards. It is expressed as Bearden units of consistency (Be) when determined either on the pressurized consistometer or on the atmospheric pressure consistometer.(2) The viscosity of a nonreversible fluid, in poises, for a certain time interval at a give
Consistometer
A tester having a stirring apparatus to measure the thickening time of cement slurries under predetermined temperatures and pressures.
Consolidation
A process of solidification of an ice mass by freezing water in voids between ice blocks.
Constant Composition Expansion
A pressure-volume-temperature (PVT) test performed on condensate reservoir fluids in which the overall composition of the fluid in a test cell remains constant as the system pressure is varied.
Constant Volume Depletion
A pressure-volume-temperature (PVT) test performed on condensate reservoir fluids in which gas is removed from the test cell to reduce the system pressure while the overall system volume remains constant.
Constructed Ice
Ice formed by surface flooding, spraying, subsurface convection cells, or other techniques.
Construction Cost
Costs include construction costs applicable to each sub-category of plant operations, except those applicable to injection wells.
Construction Overhead Flag
An indicator of whether or not the contract provides for the operator to charge construction overhead on a joint property.
Construction Overhead Negotiated Flag
An indicator of whether or not construction overhead is to be or has been negotiated.
Construction Project
(1) The installation and/or construction of capital facilities pursuant to the agreement in effect.(2) Any construction or installation undertaken for the joint account, including each subsequent addition thereto or alteration thereof or AFE'd (Authorization For Expenditure) replacement of material thereon and equipping costs of a well, but does not include drilling. Each addition, alteration, or replacement will be considered as a separate Construction Project except that multiple projects of a similar n
Consumer
SEE: Business Associate.
Contact
The interface of no significant thickness between two distinct entities, such as stratigraphic formations or fluid types within a reservoir.
Contact Date
The date the given fluid contact is determined.
Contact Depth
Measured depth to the fluid contact.
Contact Inspection
The method in which the search unit makes direct contact with the material, with a minimum couplant film.
Contact Log
A generic term referring to the log produced by any logging tool which uses pad or skid devices to make direct contact with the formation wall.
Contact Mark
Intermittent marks adjacent to the weld line resulting from the electrical contact between the electrodes supplying the welding current and the pipe surface.
Contact Method
A process of magnetizing pipe by passing a current through its wall via prods or hand held contacts. Also referred to as: Current Flow Method.
Contact Name
A person who represents a company or group on a special topic of interest.
Contact Transducer
A transducer which is coupled to a test surface either directly or through a thin film of couplant.
Contact Type
The type of fluid contact; e.g., top of gas, bottom of gas.
Contactor
(1) A processing vessel in which gas is contacted countercurrently with a solution to extract specific components in the gas; e.g., amine solution to extract acid gas; glycol solution to remove water vapor.(2) A vessel in which two or more substances are brought into solution for the purpose of removing contaminants.
Containment
Any method used on an offshore platform to collect and direct escaped liquid hydrocarbons to a safe location.
Contaminant
(1) Material, usually a mud component, which becomes mixed with the cement slurry during the displacement process, and which has a deleterious effect on cement properties.(2) A harmful or undesirable constituent; any substance that might constitute a health hazard or adversely affect desirable properties of drilling fluids.
Content Settlement Method
The type of calculation used for the settlement on the liquids content of gas, based on a unit price per mcf.
Contiguous Acreage Flag
An indicator of whether acreage is or is not contiguous. On nonproducing records, will reflect the acreage situation as initially established. On producing records, will be maintained to reflect the current status of contiguity; i.e., Noncontiguous tract(s) involved, all acreage contiguous.
Contingency Cost
Includes cost of an event (as an emergency) that is possible but not expected.
Contingent Market Order
A market order stipulating that the price must move up or down to a specified level (strike) before the order can be executed.
Continuous Flow Gas Lift
Gas lift operation in which gas is injected continuously into the liquid column. Reservoir fluids and the injected gas are produced from the wellhead at the surface without interruption.
Continuous Flowmeter
A velocimeter which is designed to measure fluid velocities in the casing.
Continuous Method
A process of searching for flaws while the magnetizing current is being applied.
Continuous Phase
The fluid phase which completely surrounds the dispersed phase that may be colloids, oil, etc.
Continuous Reeled Tubing
Tubing stored on a reel that can be run in and out of a well without making a connection.
Continuous Treatment
Describes the process of the continuous injection of liquids to treat produced fluids.
Continuous Wave
A constant flow of ultrasonic waves, as opposed to pulsed.
Contour
The gradual tapering by filing or grinding to prevent abrupt changes in the wall thickness.
Contour Line
A line connecting points of equal value (generally elevation) above or below some reference value; e.g., a datum plane. Contour lines are commonly used to depict topographic or structural shapes. The quantified properties of sediments or other phenomena can be recorded by contour lines.
Contour Map
Topographic, structural, thickness or facies differences of the mapped area shown by contour lines.
Contract
A legally enforcable agreement between two or more parties.
Contract Advanced Payment Flag
An indicator of whether or not the contract contains a clause requiring the buyer to pay seller for certain gas volumes based on projected usage, nominations, or some other criteria before the actual receipt of said volumes. This clause will usually contain a mechanism to achieve the later balancing of the advance payment account once actual deliveries occur.
Contract All Depths Flag
An indicator of whether or not the seller is dedicating all owned depths to the contract.
Contract All Wells Dedicated Flag
An indicator of whether or not all wells in the contract area are subject to the same conditions or whether one or more individual wells are not dedicated or they are dedicated at different depths, horizons, etc.
Contract All Wells Price Adjustment Flag
An indicator of whether or not there are no price adjustment requirements or that the basic price will be adjusted upward or downward if contractual and/or regulatory requirements are met.
Contract Amendment Clause
A clause which amends or modifies an existing clause in a contract, including previous (instances of) contract amendment clauses.
Contract Amendment Document Date
The date the contract amendment was prepared, or associated with the instrument which constitutes the amendment or letter.
Contract Amendment Effective Date
The date a contract amendment goes into effect.
Contract Amendment Letter Type Code
An indicator of the type of amendment to a contract or to classify a type of operational letter; e.g., area covered by contract, accounting procedure, assignment, buyer address or name.
Contract Arbitration Flag
An indicator of whether or not the contract provides for settlement of disputes by arbitration; i.e., by a third party.
Contract Area Rate Clause
SEE: Area Rate Clause.
Contract Area Rate Flag
An indicator of whether or not the gas purchase contract contains an area rate clause.
Contract Area Rate Percentage
The percentage of the applicable area rate provided to be paid for gas under a gas contract.
Contract Assignment Permitted Flag
An indicator of whether or not the contract can be assigned to a third party.
Contract Beginning Effective Date
The date that the data pertaining to a legal document, agreement, contract, change of ownership, transaction, or authorization either went into effect or is to go into effect; i.e., the date that a particular business associate gained ownership into an identified property.
Contract Btu Adjustment Base
The denominator of a fraction of which an actual British thermal Unit (BTU) value per cubic foot is the numerator and which will be used to adjust the contract current price or percent.
Contract Btu Adjustment Flag
An indicator of the type of British thermal Unit (BTU) adjustment required by the contract. This may involve gas quality and/or price; e.g., No provision, Proportional to specific base, Downward from specified base, Upward from specified base.
Contract Btu Basis
Identifies the contract requirement that the British thermal unit (BTU) value of the gas be determined on a wet, dry or actual basis.
Contract Btu Pressure Base
The pressure specified in a gas contract for the determination of the British Thermal Unit (BTU) content of the gas.
Contract Cancellation Advanced Days Count
The number of days before a cancellation is effective. One or more parties to the contract may have the right to cancel the agreement before the end of the primary term by serving written notice to the other party(ies) under the cancellation provisions of the contract. The written notice requires a specified time before the intended effective date of cancellation.
Contract Change Frequency Interval
The time between price revisions.
Contract Clause
A set of text that describes a distinct section of a contract, usually addressing a separate subject.
Contract Clause Set
A set of clauses that may be applied in contracts. These sets may be prepared by a government, an association, or a company and accepted by industry.
Contract Component Retention Percentage
The percent of the component which the owner may acquire or retain under the contract.
Contract Compression Cost Flag
An indicator of whether there are or are not provisions in the contract pertaining to compression costs which may qualify the properties under the contract for production related cost.
Contract Conditioning Cost Flag
An indicator of whether there are or are not provisions in the contract pertaining to conditioning costs which may qualify the properties under the contract for production related costs.
Contract Counterpart Document Date
The date on which the associated owner has signed a counterpart to the contract. There may be one or many counterparts to a contract.
Contract Current Price Or Percentage
The current contract price including all escalations or revisions that have occurred. This may represent a decimal rather than a price. The decimal is required by some contracts to calculate the contract minimum.
Contract Date
The date on which the parties to a contract acknowledge agreement has been reached. If no date is stipulated in the contract, the date of execution by the last party executing the contract will be used. This date usually appears on the first or second page of the contract.
Contract Dedication Limit Flag
An indicator of whether or not gas committed under a gas contract is limited by depth, volume, formation, or if there is no provision.
Contract Dedication Type Code
An indicator of the type of acreage or other dedication under a contract; i.e., Leases owned now and hereafte, Leases owned now, Processed gas from plant, Specified lease(s).
Contract Delivery Cost Flag
An indicator of whether there are or are not provisions in the contract pertaining to delivery costs which may qualify the properties under the contract for production related costs.
Contract Delivery Date
The date in the contract by which the company shall commence the actual taking of the gas under a gas purchase contract.
Contract Depth Restriction
Identifies any depth restriction that applies to the contracted acreage.
Contract Designation
The contractual right, title, share or role possessed or belonging to a business associate participating in a contract.
Contract Expiration Date
The date the primary term of a contract expires.
Contract Extension Allowed Flag
An indicator of whether or not the contract provides for extending the primary term other than through an Evergreen Clause.
Contract First Delivery Date
The date the product is first delivered under a contract.
Contract Fuel Cost Flag
An indicator of whether or not the contract specifies that cost is to include fuel for the rig.
Contract Gas Adjustment Temperature
The temperature which the contract requires for the gas volume to be adjusted. Normally measured in Fahrenheit degrees and defaults to 60 (standard), if not otherwise specified.
Contract Lease Percentage
The lease owners entitled share of production after processing.
Contract Lower Btu Adjustment Gap
If the actual British thermal unit (BTU) is greater than this limit and less than the contract upper BTU adjustment gap limit, then no BTU adjustment is made.
Contract Maximum Btu
This is the maximum British thermal unit (BTU) value permitted by contract as an adjustment to the calculation of gas values. If the actual BTU is greater than the maximum, then the maximum is used for BTU adjustments to gas values.
Contract Maximum Delivery Pressure Measurement
The maximum pressure at the delivery point as specified in the gas contract.
Contract Maximum Quantity
The maximum quantity of gas the seller is required to make available to the purchaser during a specified period under terms of a gas sales contract.
Contract Minimum Btu
This is the minimum British thermal unit (BTU) value permitted by contract as an adjustment to the calculation of gas values. If the actual BTU is less than the minimum, then the minimum is used for BTU adjustments to gas values.
Contract Minimum Delivery Pressure Measurement
The minimum pressure at the delivery point as specified in the gas contract.
Contract Minimum Maximum Flag
An indicator of whether or not the content value may be adjusted to conform to contractual minimums and/or maximums.
Contract Minimum Quantity
The minimum quantity of gas the purchaser is required to take during a specified period under terms of a gas sales contract.
Contract Mutual Interest Area
Specified land area where two or more operators act independently, but all expenses and revenue for the specified land area are shared by the operators based upon a predetermined percentage split applicable to the contract.
Contract Number
The company assigned number to uniquely identify a contract.
Contract Party Interest Type
Designates the party's type of interest in a contract; e.g., owner; buyer; seller.
Contract Party Name
The name of a party to a contract as it appears on the contract and as it is updated with successors' names.
Contract Percentage
The initial decimal used to calculate a contract minimum price.
Contract Pressure Base
The absolute pressure per cubic foot specified for the determination of the number of mcf of gas measured by a certain meter to which the contract price is applicable.
Contract Price
The initial rate used to calculate a contract minimum price.
Contract Price Basis
Denotes the basis for determining the various oil and/or gas prices stipulated by contract.
Contract Price Effective Date
The date on which the current contract price or percent is effective.
Contract Price Escalation Change Date
The date on which the next price escalation or deescalation is due.
Contract Price Escalation Rate
The amount that the contract provides as an increase or decrease in contract price.
Contract Price Escalation Start Date
The month and day on which a contract price escalation cycle began.
Contract Price Escalations Count
The number of price escalations provided by the contract.
Contract Pricing Code
An indicator of the type of price the contract price represents; e.g., British thermal unit (BTU) delivery specifications, Contract percent minimum, Contract price minimum, Content price minimum.
Contract Producer Percentage
The percent of the allocable lease value (or price) for a product that is paid to the producer. This percentage is determined from contract provisions.
Contract Product Percentage
The contract percent used to adjust the total value for a product to arrive at the final settlement value.
Contract Provision Action Date
The date that a specific contract provision requires certain action to be taken.
Contract Provision Action Notice
The notice required prior to exercising an option or taking a certain action under a contract.
Contract Provision Review Frequency
This identifies how much time should elapse between reviews of contract provisions.
Contract Provision Type Requiring Action
Indicates the type of contract provision requiring action.
Contract Quantity Adjustment Flag
An indicator of whether or not the contract percent should be adjusted based on the quantity of gas produced for all leases under the contract.
Contract Quantity Increment
The percentage amount that the value is changed ( + or - ) due to a contract stipulation regarding volume of gas delivered for a contract.
Contract Quantity Unit Of Measurement
Identifies the units in which the contract quantity is to be measured.
Contract Reference
Catalog or cross reference table that identifies a specific contract as being referenced by another contract. For example, an instance of subcontract may refer to a head contract instance.
Contract Release Reason
Identifies why the preceding contract was terminated and gas was released to the new contract.
Contract Service Type
Identifies the type of services to be performed by an outside vendor as specified by a contract.
Contract Signatory Code
An indicator of how each outside party has entered into the contract. Examples are: Executed/ratified, Successor party, Approved under unit operating agreement, No formal document, Acting agent, Prior party.
Contract Special Negotiations Date
The date on which a special negotiation provision of a contract is required or is open to action.
Contract Special Negotiations Frequency
Identifies how often a particular contract requirement should be reviewed.
Contract Special Negotiations Notice
Identifies the length of time a written notice is required to exercise certain options or contract requirements.
Contract Special Negotiations Type
Identifies the type of special negotiations required for a contract; e.g., redetermination; renegotiations.
Contract Specific Gravity Test Interval
The interval between specific gravity tests required by contract.
Contract Status Code
Indicates the status of each contract; e.g., Active Assigned (rights and obligation under contract transferred to another party.); Correction (information entered in error corrected.); Expired (the contract expired under its own terms.) Modified (information changed in accord with authorization.); Terminated (action was taken to terminate the contract.)
Contract Status Date
Date that the indicated status of the contract became effective.
Contract Sulphur Test Frequency
The interval between sulphur content tests required by contract.
Contract Term
The period of time that the provisions of the contract are legally binding to the contract parties, which may be represented by the productive life of the lease(s) under the contract.
Contract Term Period Code
An indicator of the span of time in which the contract term is expressed; e.g., months, years, life of lease.
Contract Termination Date
The contract may specify an exact date on which either party may cancel the contract or the termination date may be indefinite if the agreement remains in effect for the production life of the lease(s) under the contract.
Contract Treatment Cost Flag
An indicator of whether or not there are provisions in the contract pertaining to treating costs which may qualify the properties under the contract for production related costs.
Contract Type Code
Identifies the nature of each of the many types of contracts that are negotiated; e.g., Operating agreement; Gas sales; Farm in/out (with operating agreement); CO2 contract; Working interest area.
Contract Upper Btu Adjustment Gap
If the actual British thermal unit (BTU) is less than this limit and greater than the Contract Lower BTU Adjustment Gap limit, then no BTU adjustment is made.
Contract Verification Date
The date on which the pricing codes associated with this contract were verified for correctness.
Contract Verification Flag
An indicator of whether or not the pricing codes contained on this contract have been reviewed and are correct.
Contract Verifier Name
The name of the person verifying the contract pricing codes for this contract.
Contract Volume
Quantity of gas based on measurement conditions and procedures specified in a gas sales contract.
Contract Volume Description
Text briefly describing the quantity of gas to be purchased or sold or how such quantity shall be determined by contract provisions.
Contract Volume Limit
The volume used as a limit to determine if a quantity adjustment should be made to the contract.
Contract Well Cost
The agreed upon cost for drilling the well, or portion thereof, based upon the specific type of contract awarded.
Contracted Sweep
A contraction of the horizontal sweep on the viewing screen of the ultrasonic instrument. Contraction of this sweep permits viewing reflections occurring over a greater depth of material or duration of time.
Contractor
(1) Any outside individual, company, firm, agency, etc. which provides goods and/or service as specified within a contract; e.g., drilling a well.(2) Any person or company who contracts all or part of oil and gas well drilling or servicing.
Contribution
Contributions, generally referred to as dry hole or bottomhole contributions, are amounts paid and/or interests in acreage assigned to promote the drilling of wells on acreage in which the contributor does not own a working interest or does not, by reason of the contribution, acquire a working interest in the test well tract. A contribution is for the acquisition of geological information only. Some deals may comprise both a contribution and the acquisition or retention of an interest in acreage. In such
Contribution Well
SEE: Farm-Out Well.
Control Cylinder
Hypothetical limits in the form of a cylinder around the planned trajectory of the wellbore and within which the wellbore path is to be maintained.
Control Echo
In ultrasonic testing, the reference signal from a constant reflecting surface, such as a back reflection.
Control Feature
A documented activity to ensure conformance with specific requirements of applicable specifications.
Control Head
A heavy fitting that screws on the innermost casing top of a well.
Control Line
An individual conduit utilized to transmit control signals to the Surface Controlled Subsurface Safety Valve (SCSSV).
Control Manifold
The system of valves and piping to control the flow of hydraulic fluid to operate the various components of the blowout preventer stack.
Control Panel
Switches and devices to start, stop, measure, monitor or signal what is taking place.
Control Pod
An assembly of subsea valves and regulators which when activated from the surface will direct hydraulic fluid through special apertures to operate blowout preventer equipment.
Control Valve
An automatically actuated valve for controlling flow, in reponse to an impulse from an instrument which measures the flow, or some function affected by it; e.g., pressure.
Control Well
A wellbore segment drilled to intercept a wellbore that has blown out or is out of control.
Controllable Material
(1) Material which is ordinarily so classified and controlled by the operator in the conduct of the operations of the property and as agreed to by the parties to the agreement.(2) COPAS: Material which at the time is so classified in the Material Classification Manual as most recently recommended by the Council of Petroleum Accountants Societies of North America or in the Controllable Material Price Catalogue as most recently recommended by the Petroleum Accountants Society of Canada.
Controlled Aggregation
A condition in which the clay platelets are maintained stacked by a polyvalent cation, such as calcium, and are deflocculated by use of a thinner.
Controlled Area
A defined area that requires control of access, occupancy, and working conditions for protection purposes.
Controlled Directional Drilling
SEE: Directional Drilling.
Controlled Directional Well
SEE: Directional Well.
Conventional Core Sample Taken Flag
An indicator of whether a conventionalcore sample was taken.
Conventional Operation
A well activitiy conducted using a rig equipped with fluid pumps, rotary table, and other equipment designed to perform well workovers, recompletions, and other work which requires removal of the Christmas tree and pulling or manipulation of the tubing.
Conversion
SEE: Well Conversion.
Conversion Clause
A clause in an assignment or other instrument providing for the conversion, either automatically or at the option of one of the parties, of one interest granted or reserved into another interest; i.e., conversion of an overriding royalty or net profits interest into a share of the working interest.
Convertible Interest
An interest which is convertible into an interest of another type. By the terms of the instrument creating an overriding royalty; i.e., it may be provided that at the owner's option the interest may be converted after the completion of a well to a share of the working interest.
Convertible Working Interest
The working interest the company can obtain under the contract terms involving a given exploratory well.
Conveying Speed
On a decanting centrifuge, the difference in speeds between the outer bowl and the screw conveyor in rpm.
Conveyor
A mechanical device for moving material from one place to another.
Cooler
(1) A refrigerated water bath used to cool pressure charged gas lift valves to 60 degrees F prior to setting them. (2) A heat exchanger using air or water to cool a vapor or liquid.
Cooling Tower
An open-air heat exchanger which uses air-cooled recirculating water with the purpose of cooling a hot process fluid.
Cooling Tower Basin
The lower section of a cooling tower which stores water after it has gone through the cooling process, and prior to recirculation.
Coordinate Transformation
A method and set of parameter values used to convert from one coordinate system to another coordinate system.
Copas
Council of Petroleum Accounting Societies. Studies petroleum accounting issues, particularly those where joint operations are involved, and periodically issues guidelines (bulletins) on those issues.
Copas Accounting Year
One of the exhibits attached to the operating agreement on a property is the accounting procedure. Normally, all new agreements have some type of accounting procedure that was developed by Council of Petroleum Accounting Societies (COPAS). The COPAS accounting year indicates that a COPAS accounting procedure exists, and the year of the procedure.
Copolymer
A substance formed when two or more substances polymerize at the same time to yield a product which is not a mixture of separate polymers but a complex having properties different from either polymer alone; e.g., polyvinyl acetatemaleic anhydride copolymer (clay extender and selective flocculant); acrylamide-carboxylic acid copolymer (total flocculant).
Copper Free Aluminum
Aluminum alloys containing 0.4% or less copper. Also referred to as: Low Copper Content Aluminum.
Copper Treater
A vessel in which residual mercaptans are chemically converted to less objectionable disulfides by reaction to air or oxygen in contact with a copper chloride catalyst.
Core
A rock sample extracted from the borehole by various coring methods.
Core Analysis
Laboratory work performed on core samples to determine the physical characteristics and/or fluid content of the samples.
Core Analysis Date
The date that the core sample was analyzed.
Core Analysis Interval
The depth interval for which core analysis is performed.
Core Analysis Type
The type of analysis performed on the core sample; e.g., Boyles law; summation of fluids; grain density; resaturation; Washburn-Bunting.
Core Analyzed Type
The type of core that was analyzed; e.g., washed cuttings; conventional core; diamond core; plug.
Core Barrel
A device used in rotary drilling to cut cores. The core barrel, varying in length, is run at the bottom of the drill pipe or in conjunction with a special type of bit.
Core Bit
An item of equipment which is designed to drill a hole of a given diameter while leaving a smaller central column intact. Typically this central column slides into a specifically designed barrel and is retrieved for analysis.
Core Bit Head
The bit attached to the bottom of a core barrel for the purpose of obtaining formation samples.
Core (conventional)
SEE: Conventional Core.
Core Date
Date on which the core was recovered.
Core Diameter
The diameter of the recovered core.
Core Extraction Method Type
The extraction method used in analyzing the core; e.g., Dean Stark; gas driven solvent; retort.
Core Flow Efficiency
Core flow efficiency is the ratio of the experimental permeability ratio to the theoretical permeability ratio, (kp/ko)/(ki/ko), for the same total core penetration.
Core Gamma Log
A gamma ray log which is run directly on the core and not in the borehole.
Core Graph
Results of core analysis illustrated or graphed in the form of a log.
Core Interval Base Depth
The base depth of the interval of the coring activity.
Core Interval Length
The length of the wellbore interval cored.
Core Interval Top Depth
The top depth of the interval of the coring activity.
Core Oil Saturation Percentage
The weighted saturation of oil in the core sample, expressed as a percentage or fraction.
Core Oriented
A core sample whose position, including compass orientation, in the reservoir has been measured and recorded.
Core Permeability Value
The laboratory value of the permeability of the core analyzed.
Core Plug Length
The length of the core plug; a sample removed from the total core length.
Core Plug Orientation
Plug orientation when bored from core; e.g., horizontal; vertical; 90 degrees to horizontal.
Core Porosity Analyzed Length
The total length of the cored interval analyzed for porosity.
Core Porosity Type
The porosity of the core analyzed; e.g., intergranular; sucrosic; cavernous.
Core Recovery Length
Amount of core recovered from a conventionally cored interval.
Core Recovery Mechanism Type
The type of core recovery mechanism used to recover the core; e.g., rubber sleeve; fiberglass barrel; sponge.
Core Run Identifier
An identifying number, unique within a wellbore path, assigned to each core run. This number is assigned only to conventional cores and not to sidewall cores.
Core Sample
Cylindrical sections of rock cut by the drill bit and removed from the wellbore for study.
Core Sample Drill
SEE: Core Barrel.
Core Sample Type
The sample type of core or sample taken from the interval.
Core Show Length
The length of cored interval that exhibits the indicated quality and type of show.
Core Show Type
The type of show indicated in the cored interval.
Core (sidewall)
SEE: Sidewall Core.
Core Slab
A lengthwise slice of the core.
Core Type
The type core recovered from the borehole.
Core Water Saturation Percentage
The weighted saturation of water in the core sample.
Coring
The well activity of extracting a core.
Coring Fluid Type
The type of fluid that was in the borehole at the time the coring operation.
Coring Report Remark
Text indicating significant information about the conduct on the coring operation. This field can also be used to note the existance and location of any rig site geologic interpretation, including visual inspections, core descriptions, etc.
Corner Effect
The reflection of a sound beam directed normal to the intersection of two perpendicular planes.
Corporation Flag
An indicator of whether or not a business associate subject to Federal excise tax on crude oil is classified as a corporation on IRS Form 6248.
Correction
A quantity that is applied to a measured quantity to account for known effects. It is used to reduce a measurement to some arbitrary standard.
Corrective Jetting Run
Action taken with a directional jet bit to change the direction or inclination of the wellbore axis.
Correlation
The matching over horizontal distance (from well to well), of zones or intervals over which the same geological or other events are interpreted as having occurred.
Correlation Length
The length of zone or interval over which a depth-related correlation is made in order to determine the depth wise displacement between log curves on which the same geological events have been interpreted.
Corrosion
The adverse chemical alteration on a metal or the eating away of the metal by air, moisture, or chemicals. Usually an oxide is formed.
Corrosion Agent
Any substance causing corrosion.
Corrosion Bomb
A pressure test cylinder containing a polished copper strip used to detect the presence of hydrogen sulfide and other corrosive compounds in LPG. Discoloration of the copper strip when the cylinder is filled with LPG and held at 122 degrees Fahrenheit for one hour indicates the presence of a corrosive material.
Corrosion Erosion
The phenomenon of a protective film of corrosion product being eroded away by the erosive action of the process stream, exposing fresh metal which then corrodes. Extremely high metal weight loss may occur under these conditions.
Corrosion Fatigue Failure
Failure of a metal exposed to repeated loading in corrosive service.
Corrosion Inhibitor
Any agent which, when added to a system, slows down or prevents a chemical reaction or corrosion. Corrosion inhibitors are used widely in drilling and producing operations to prevent corrosion of metal equipment exposed to hydrogen sulfide, carbon dioxide, oxygen, salt water, etc. Common inhibitors added to drilling fluids are filming amines, chromates, and lime.
Corrosion Product
The material which results from a metal combining with its corrosive environment.
Corrosion Resistant Ring Groove
A ring groove lined with metal resistant to metal loss corrosion.
Corrosive Gas
A gas which when dissolved in water or other liquid causes metal corrosion. Usually included are hydrogen sulfide (H2S), carbon dioxide (CO2) and oxygen (O2).
Corrosive Hydrocarbon Service
Process streams which contain water or brine and carbon dioxide (CO2), hydrogen sulfide (H2S), oxygen (O2) or other corrosive agents under conditions which cause metal weight loss.
Corrugated Plate Interceptor Unit
Nonpressure separation process which uses a series of corrugated plates to remove oil from water.
Cost Code
Identifies costs detail; e.g., drilling/dry hole, completion, total.
Cost Depletion
In federal income taxation, the method of figuring the depletion allowance in relation to the taxpayer's investment.
Counterbalance
A weight attached to a crank, pulley rim, walking beam or other moving part of a pumping unit providing for even distribution of loads and for the reduction of peak torque during the up and down stroke.
Countershaft
The main shaft of a gear box.
Counterweight
Weight used to supplement the weight of the machine in providing stability for lifting working loads and usually attached to rear of revolving upperstructure. Also referred to as: Ballast.
Country
Major political division of the topography, biology, or culture of an area.
Country Abbreviation
The abbreviation for a country.
Country Code
An indicator to identify sovereign nations, colonies, areas independent in terms of internal affairs but under the protection of another country, overseas territories, and dependencies of other countries.
Country Name
A name that identifies a country.
Country Subdivision
A territory governed as an administrative or political unit of a country; e.g., state; province.
County Name
The name of the county or parish, within a state.
County Name Abbreviation
Abbreviated name of a county or parish.
Couplant
A material (usually a liquid) used between ultrasonic transducer and the test specimen to conduct ultrasonic energy between them.
Coupling
A mechanical means for joining two sections of riser pipe in end to end engagement.
Coupling Mill End
The end of the pipe to which the coupling is applied at the mill. Also referred to as: The box end of integral joint pipe.
Coupling Outside Diameter Value
The outside diameter of the given coupling type.
Coupling Preload
Compressive bearing load developed between pin and box members at their interface. This is accomplished by elastic deformation during makeup of the coupling.
Coupling Strength Value
The pressure required to yield the given coupling type.
Coupon
Small metal strips which are exposed to corrosive systems for the purpose of determining nature and severity of corrosion.
Course Displacement Value
The course length multiplied by the displacement.
Course Length
The measured length between survey points.
Coutler Counter
An electronic device used in measuring the finer sizes of clastic sedimentary particles; e.g., silt; clay.
Coverage
SEE: Nominal Fold.
Cpa
SEE: Canadian Petroleum Association.
Cpi Unit
SEE: Corrugated Plate Interceptor Unit.
Cpr
SEE: Cardiopulmonary Resuscitation.
Crack
(1) A stress induced separation of the metal which, without any other influence, is insufficient in extent to cause complete rupture of the material.(2) A planar discontinuity formed by separation of previously continous material.
Cracker
Bottomhole assembly in which single joints of drill string can be run between drill collars to produce a limber assembly.
Cracking
A conversion process that breaks big molecules into smaller ones by using heat, pressure and catalysts. Lighter oils can be made from the heavier products of the distillation process. Two types of cracking processes are thermal cracking and catalytic cracking.
Crater
A large sink hole or cavity around a wellbore origin. Sometimes accompanies a violent blowout during which the surface surrounding the wellbore origin drops.
Crawler
SEE: Pig.
Creaming Of Emulsion
The settling or rising of the particles of the dispersed phase of an emulsion as observed by a difference in color shading of the layers formed. This can be either upward or downward creaming, depending upon the relative densities of the continuous and dispersed phases.
Created Fracture
An induced fracture by means of hydraulic or mechanical pressure exerted on the formation.
Credit Reference Number
The number assigned to a credit.
Credit Taken Amount
The amount of credit applied to reported amounts.
Creep
(1) Time dependent increase in strain during a state of constant stress.(2) The gradual deformation of metals or plastics under loads applied for a long time.
Crest
(1) The highest point of a given stratum in any vertical section of a fold.(2) The top of a thread.
Crest Clearance
The distance between the crest and root of mating threads.
Crest Truncation
The distance between the sharp crest (crest apex) and the finished crest.
Cricondenbar
The maximum pressure at which a vapor phase can exist in a multi-phase fluid system.
Cricondentherm
The maximum temperature at which a liquid phase can exist in a multi-phase fluid system.
Crippled Bit
By removing one cone, a drilling bit is crippled and made to act erratically. Such bits have been used for deviation drilling.
Critical Angle
The smallest angle of incidence in which a sonic, electromagnetic, or optic wave that strikes an interface will be totally reflected.
Critical Flaw
A defect which is capable of causing a failure.
Critical Flow
The rate at which the velocity through an orifice or small opening has reached it's maximum, and remains a constant. The rate of flow is directly proportional to upstream pressure, and changes only with upstream pressure. Downstream pressure has no effect on flow rate when critical flow velocity is obtained.
Critical Flow Prover
A steel tube 12" long with provisions for installing an orifice plate at one end. Two sizes are available, either 2" or 4" internal diameter. Two connections are provided on tube one for a thermometer bulb and the other for connecting a pressure recording meter.
Critical Gas Saturation
The lowest gas saturation in the reservoir rock at which gas will flow. When the gas saturation is less than the critical value, the permeability to gas is zero.
Critical Pressure Measurement
The pressure at which a vapor turns to a liquid at the critcal temperature.
Critical Saturation
The saturation of a fluid phase that must be exceeded for that phase to become mobile.
Critical Temperature
The temperature above which a particular substance exists only as a gas no matter what the pressure.
Critical Velocity
That velocity at the transitional point between laminar and turbulent types of fluid flow. This point occurs in the transitional range of Reynolds numbers of approximately 2,000 to 3,000.
Critical Volume
The inverse of density at the critical point of a fluid, describing the volume occupied by a fluid of unit mass.
Critical Z-factor
The real gas deviation factor at the critical point.
Crooked Hole
SEE: Crooked Wellbore.
Crooked Hole Area
An area where the drilling tends to produce wells with crooked wellbores.
Crooked Hole Tendency
A characteristic of the rocks, bottomhole assembly, or drilling practices to cause a crooked wellbore to be drilled.
Crooked Wellbore
A wellbore path that has numerous unintentional deviations from the vertical.
Cross
A pressure containing fitting with a minimum of four openings. Usually all four openings are at 90 degrees to one another. Crosses may be threaded or flanged.
Cross Assignment
When several producers, either voluntarily or by state regulation, pool acreages to form a unit. They may cross-assign their leases to one another, creating a common obligation to each royalty owner.
Cross Head
In an integral reciprocating compressor, the connecting piece which transposes oscillating motion of the connecting rod into horizontal motion of the compressor piston rod.
Cross Talk
An unwanted condition in which acoustic energy is coupled from the transmitting crystal to the receiving crystal without propagating along the intended path through the material.
Cross Threaded
Male and female threads do not match.
Crosscorrelation
A statistical process in which the similarity of the two waveforms from a seismic source is calculated as a function of the time shift or lag between the waveforms.
Crossline
The direction orthogonal to the inline direction.
Crossline Traverse
A collection of seismic traces from a 3D survey in which the bin node inline index remains constant.
Crossover Flange
A double or single studded adapter flange with a restricted area sealing means and with a top connection pressure rating above that of the lower connection.
Crossover Point
In multiple layer spooling of rope on a drum, the point of rope contact where the rope crosses the preceding rope layer.
Crossover Seat
A special seat for a gas lift valve which directs the pressure applied at the nose of the gas lift valve to the bellows and the pressure applied to the holes in the side of the valve to the underside of the seat. It is used most often in fluid operated valves.
Crossover Spool
Flanged equipment with a restricted area sealing means, at or near the face of its lower flange. Crossover spools are also provided with suitable means to suspend and seal around an inner string of casing or tubing. A crossover spool has a top connection with a pressure rating above that of the lower connection.
Crossplot
A plot of one parameter versus another.
Crowd The Bit
Term used to indicate that more weight is applied to the bit than needed for efficient drilling. A crowded bit will usually increase the inclination or cause an azimuth change.
Crown
The curvature of the screen deck or the difference in elevation between the high and low points.
Crown Block
Sheaves (pulley wheels) and supporting beams on top of a derrick.
Crown Valve
The uppermost valve on the vertical bore of the christmas tree above the flowline outlet.
Crude Oil
A mixture of varying proportions of hydrocarbons, natural gas, and entrained sediments and water. Crude oil exists in the liquid phase in natural underground reservoirs and remains a liquid at atmospheric pressure and 60 degrees Fahrenheit.
Crude Oil Characterization Factor
The characterization factor developed by United States Bureau of Mines (USBM) for crude oils, defined as the cube root of the molal average boiling point (degrees Rankine) divided by the specific gravity at 60 degrees Fahrenheit.
Crude Oil Posting Amount
The maximum price payable based on crude oil postings. (Flat rate contracts only).
Crusher
Equipment used to break, pound, or grind larger objects into smaller fragments.
Cryogenics
Technique utilizing extremely low temperatures to produce natural gas liquids from a raw gas stream.
Crystal
(1) A piezoelectric element in a probe or search unit.(2) (Mineralogical) A homogeneous, solid body of a chemical element, compound or isomorphous mixture, having a regularly repeating atomic structure that may be externally apparent as plane faces.
Cumulative Displacement Value
The sum of the displacement through the current reading.
Cumulative Fatigue Damage
The total of fatigue damage caused by repeated cyclic stresses.
Cumulative Gas Production Volume
The total amount of gas produced from the property/well/ reservoir from the beginning of production through a specific production date or until abandonment.
Cumulative Oil Production Volume
The total amount of oil or condensate produced from the reservoir within the well from the beginning of production through the specified production date or until the reservoir was abandoned.
Cumulative Water Production Volume
The total amount of water produced from the property/well/ reservoir from the beginning of production through a specified production date or until abandonment.
Cupronickel
An alloy of copper (70 percent or over) and nickel.
Curing
Aging of cement specimens under specified conditions.
Curing Atmospheric Pressure
The aging of cement specimens for test purposes at normal atmospheric pressure of 14.7 psi (1 kg/cm2) at sea level and temperature below about 200 F (93.3 C), for a designated period of time under certain given conditions of temperature and humidity. Also referred to as: Curing Pressure.
Current Authorization Cost
Cost associated with this appropriation/AFE number.
Current Overpayment Gross Amount
The balance of the gross value for an accounting lease associated with an overpayment that has not yet been recovered.
Current Reservoir Depth
Measured depth of present reservoir.
Current Reservoir Name
The name of the present reservoir to which the well is completed.
Current Tax Due Amount
The tax calculated and due in the current reporting period.
Current Value Balance Amount
The total accumulated value tracked against a bonus, advanced rental, or overpayment.
Current Well Activity Date
The start date of the current well site activity.
Current Well Activity Type
The current activity for the well. Reports of activities are accompanied by a start date, which defines when the well began the activity.
Curvature In The Horizontal Plane
Projection of the curvature of the wellbore onto a horizontal plane.
Curvature In The Vertical Plane
Projection of the curvature of the wellbore onto a vertical plane.
Cushion
Water, drilling fluid, or nonflammable gas placed inside of the drill pipe or tubing to control both annular and formation pressure.
Cushion Fluid Type
The type of cushion fluid; e.g., water; drilling fluid; gas.
Cushion Gas Pressure Measurement
Gas pressure equal to a liquid height to maintain pressure on the formation being tested.
Cushion Volume
The quantity of water, drilling fluid or gas placed inside of the drillpipe or tubing to control both annular and formation pressure. Usually the vertical height of the cushion.
Customer Number
The number assigned by the reporting party to the particular entry required by the regulatory agency, and used primarily to assist the reporting party in relating their database to regulatory agencies.
Cut
(1) A narrow boiling range mixture separated from a wider boiling range mixture.(2) A petroleum fraction; a product; e.g., gasoline or naphtha distilled from crude oil.(3) Crude oil contaminated with water so as to make an oil water emulsion.(4) A gouge or distortion in two or more thread crests in a line either parallel to the pipe or at an angle across the threads.(5) The effectiveness of a liquid solids separation device expressed as the particle size that is removed from the feed stream at a
Cut Oil
Oil that contains water, usually in the form of an emulsion.
Cutting
A small piece of rock that results from the chipping and/or crushing action of the drill bit during drilling.
Cuttings Type
Type of cutting from the wellbore.
Cycling
SEE: Gas Cycling.
Cyclone
A device for the separation of various particles from a drilling fluid, most commonly used as a desander. The fluid is pumped tangentially into a cone, and the fluid rotation provides enough centrifugal force to separate particles by mass weight.
Cylinder
(1) A device which converts fluid power into linear mechanical force and motion.(2) A chamber in a compressor, engine, or pump from which the piston expels fluids, gas, or air.
Cylinder Drilling
Refers to drilling in which the course of the wellbore path is held within previously determined limits set by the circumference of an imaginary cylinders extending from the surface location to the target.
Cylindrical Plot
A graphic presentation of the stratigraphic boundaries intersecting the borehole. The beds are usually plotted on a clear plastic sheet, which is rolled up to simulate the borehole and the patterns an observer might see.
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