10_Minute_Gel_Strength Shear_Stress Shear Stress required to break a gel fluid previously allowed to remain at rest for 10 minutes. 10_Minute_Gel_Test_Deflection Plane_Angle The maximum reading (deflection) taken from a direct-reading viscometer after the fluid has been quiescent for 10 minutes. 10_Second_Gel_Strength Shear_Stress Shear Stress required to break a gel fluid previously allowed to remain at rest for 10 seconds. 10_Second_Gel_Test_Deflection Plane_Angle The maximum reading (deflection) taken from a direct-reading viscometer after the fluid has been quiescent for 10 seconds. 1_Minute_Gel_Strength Shear_Stress Shear Stress required to break a gel fluid previously allowed to remain at rest for 1 minute. 1_Minute_Gel_Test_Deflection Plane_Angle The maximum reading (deflection) taken from a direct-reading viscometer after the fluid has been quiescent for 1 minutes. 30_Minute_Gel_Strength Shear_Stress Shear Stress required to break a gel fluid previously allowed to remain at rest for 30 minutes. 30_Minute_Gel_Test_Deflection Plane_Angle The maximum reading (deflection) taken from a direct-reading viscometer after the fluid has been quiescent for 30 minutes. API_Approx_Weight Weight_Per_Joint API approximate weight of one section API_Code Identifier Code used by the API (American Petroleum Institute) to identify an industry related entity, e.g., Service Company, Country, another Standard organization, etc. API_Country_Code API_Code Code used by the API (American Petroleum Institute) to identify sovereign nations, colonies, overseas territories, etc. API_Design Data_Valued_Property The API design specification that the equipment meets API_Entrance_Hole_Diameter Perforation_Diameter Entrance hole diameter in an API Section I test API_Grade Grade Grade used by the API (American Petroleum Institute) to qualify material and/or equipment used in the industry, e.g., Tubulars. API_Gravity Density A measure of hydrocarbon density equal to 141.5/(specific gravity @ 60 degF) - 131.5; usually reported with a temperature. API_Neutron Neutron_Porosity The Neutron calibration measurement determined using the API test pit. This quantity is associated with the natural formation hydrogen concentration. API_Nom_Weight Weight_Per_Joint API nominal weight of tube with joint for drill pipe and casing pipe API_Pin_Conn_Size Diameter API pin connection size API_Pin_Conn_Type Type API pin connection type API_Plastic_Viscosity Plastic_Viscosity Measure of the internal resistance to fluid flow attributable to the amount, type, and size of solids present in a given fluid. When using the direct-indicating viscometer, it is found by subtracting the 300-rpm reading from the 600-rpm reading of a Fann35 rheometer. API_Range Length API range characteristic for length of tubular goods API_Reference Publication_Title The name of an API (American Petroleum Institute) reference, e.g., Bulletin D12A. API_Total_Penetration Perforation_Length Total penetration in an API Section I test API_Well_Number Identifier A unique well identification number as defined in the API (American Petroleum Institute) Bulletin D12A, as amended API_Yield_Stress Yield_Stress Resistance to initial flow; the stress required to start fluid movement. When using the direct-indicating viscometer, it is found by subtracting plastic viscosity (API_Plastic_Viscosity) from the 300-rpm reading of a Fann35 rheometer. ASAP_Depth_Parameter Data_Valued_Property Private structure used by the ASAP autotracking application; holds depth variations of time-domain Property ASAP_Parameter. ASAP_Parameter Data_Valued_Property Private structure used by the ASAP autotracking application. Abandon_Pressure Pressure The pressure at which a reservoir was or is expected to be abandoned. Abandon_Time Date The time that a reservoir was or is anticipated to be abandoned. Absolute_Abundance Amount Quantity of members in a group, as expressed as a count and count units, such as 5 sacks, 3 boxes, or 4 items. Absolute_Delta_Flowrate Flowrate Absolute value of Delta Flow Rate. Calculated from the flowrate data contained in the Flow History, i.e., Q(associated Flow Period) - Q(previous Flow Period). Absolute_Permeability Permeability The permeability of porous material when completely saturated with a wetting fluid and without the influence of non-Darcy (turbulence) effects. Also called "intrinsic" permeability. Absolute_Permeability_Gas Absolute_Permeability The permeability of porous material when completely saturated with gas. Absolute_Permeability_Oil Absolute_Permeability The permeability of porous material when completely saturated with oil. Absolute_Permeability_Water Absolute_Permeability The permeability of porous material when completely saturated with water. Absolute_Roughness Rugosity Average amplitude of rugosity, such as the variations in the radius of tubing. Absolute_Time Time A time value which is intended to fix an event in time, such as a geological time, a date, or the start time of a process. Acceleration Data_Valued_Property The rate of variation of velocity with time. Accident_Type Type Type of Quality, Health, Safety, and Environmental accident such as Fluid Spill, Kick While Drilling, Kick While Tripping, ... Accuracy Statistical_Property The extent to which a measurement approaches the true value of a quantity; usually expressed as a fraction of the true value or, for instrumentation, full scale. Accuracy_Description Description Textual description of the data related to accuracy. Acid_Concentration Chemical_Concentration Concentration of acid. Acid_Treatment_Count Count Number of acid jobs Acoustic_Amplitude Amplitude A measure of the maximum departure of an acoustic wave from the average value Acoustic_Attenuation Attenuation The amount of reduction in the amplitude of an acoustic wave. Acoustic_Attenuation_Rate Attenuation_Rate A measure of the rate of attenuation of an acoustic wave per unit length. Acoustic_Caliper Caliper Borehole diameter as estimated by an acoustic logging device. Acoustic_Contrast Acoustic_Impedance Interface property which is the difference between the Acoustic Impedance values of two adjacent beds. Acoustic_Dispersion Data_Valued_Property Variation of acoustic velocity with frequency. Dispersion may be normal (velocity decreases with frequency) or inverse (velocity increases with frequency). Acoustic_Energy Energy Energy of an acoustic wave, calculated as the sum of the squares of the amplitudes of the elements in a wavelet, sometimes multiplied by a proportionality constant. Acoustic_Impedance Data_Valued_Property Property which controls the propagation of an ultrasonic wave in a medium. It is the product of the material density and the acoustic wave velocity within the material. Acoustic_Impedance_Ratio Ratio Ratio of the acoustic impedance of two adjacent beds or intervals Acoustic_Quality_Indicator Quality_Indicator Property used to indicate quality or confidence of data from an acoustic survey. Acoustic_Slowness Interval_Transit_Time The time interval per unit length, Delta-T, necessary to attenuate a traveling acoustic wave. Applies to all types of Delta-T: Compressional, Shear and Stoneley. Acoustic_Travel_Time Time_Interval The total time required for an acoustic wave to travel from one point to another. Acoustic_Velocity Velocity The velocity of an acoustic wave which represents the rate at which the wave travels from one point to another. Used generally for all elastic and seismic waves. Acquisition_Break_Time Time_Interval Acquisition system break time Acquisition_Enable_Flag Flag Flag indicating whether or not acquisition is enabled for this activity. Acquisition_File_Number Ordinal_Number Acquisition system file number Acquisition_Rate Frequency Channel acquisition rate: number of data samples acquired per unit of time Acquisition_Shot_Number Ordinal_Number Acquisition system shot number Acquisition_Shot_Time Time_Interval Acquisition system shot time Acquisition_Transit_Time Transit_Time Acquisition system transit time Acquisition_Type Type Type or mode of data acquisition Activation_Pressure Pressure Pressure at which recording should begin Activation_Temperature Temperature Temperature at which recording should begin Activity_Code Code The specific catalog-controlled code of an Activity performed on a Well, a Region, or an Earth subsurface component. Activity_Name Name Commonly used name for an Activity. Activity_Number Identifier External identifier assigned to an activity (e.g. job or proposal number). Activity_Type Type The type of an Activity performed on a Well, a Region, or an Earth subsurface component, e.g. Drilling, Seismic, Logging, etc. Address Data_Valued_Property The location where some entity or information may be found or contacted. Adjustable_Choke_Flag Flag Flag indicating whether this flow period was performed on an adjustable choke, i.e., when set: adjustable choke, not set: fixed choke. Admittance Data_Valued_Property The reciprocal of Impedance. The property of a medium to allow for the flow of an alternating current. Adsorption Data_Valued_Property The adhesion in an extremely thin layer of molecules (as of gases, solutes, or liquids) to the surfaces of solid bodies or liquids with which they are in contact Affine_Coeff_A Coefficient Coefficient "A" in an Affine transformation between two coordinate systems. The input and output coordinate systems may be local or projection systems. Affine_Coeff_B Coefficient Coefficient "B" in an Affine transformation between two coordinate systems. The input and output coordinate systems may be local or projection systems. Affine_Coeff_C Coefficient Coefficient "C" in an Affine transformation between two coordinate systems. The input and output coordinate systems may be local or projection systems. Affine_Coeff_D Coefficient Coefficient "D" in an Affine transformation between two coordinate systems. The input and output coordinate systems may be local or projection systems. Affine_Coeff_E Coefficient Coefficient "E" in an Affine transformation between two coordinate systems. The input and output coordinate systems may be local or projection systems. Affine_Coeff_F Coefficient Coefficient "F" in an Affine transformation between two coordinate systems. The input and output coordinate systems may be local or projection systems. Agency_Lease_Number Identifier Unique lease number assigned by leasing agency Agreement_Interest Proportion Percentage of interest held by one of the potentially many organizations holding a lease agreement. Agreement_Status Status Status of a lease agreement. Air_Supply_Flowrate Flowrate The flowrate value which the air supply should be able to achieve Air_Supply_Pressure Pressure Air supply pressure; for a burner, the pressure required to achieve effective atomization Albite_Volume_Fraction Volume_Fraction The volume fraction of albite with respect to the total volume. Alkalinity Chemical_Concentration Concentration of basic anions in an aqueous solution (e.g. OH-, CO3-- and HC03-) Alkhalifah_Eta Anisotropy Alkhalifah's eta anisotropy parameter, describing the relationship between horizontal and moveout Compressional velocities. Allowed_Position Type Allowed position of an equipment item with respect to the assembly in which it operates. Alphacode Code Synonym of Code using the alphabet character set. Alternate_Phone_Number Phone_Number Alternate phone number, including country code. Altitude Height Height above a reference level, such as mean sea level. Aluminum_Concentration Concentration Concentration of Aluminum by weight. Aluminum_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of aluminum to total dry weight Aluminum_Yield Elemental_Yield Elemental contribution of Aluminum with respect to total. American_Aircraft_Regulation Code American Aircraft Transportation Regulation pertaining to a type of material or equipment, e.g., DOT-E-752 Cargo Only Amount Data_Valued_Property Quantity, total number Amount_Of_Substance Amount The amount of a particular substance (e.g. chemical) expressed in units of moles. Amplitude Data_Valued_Property The extent or range of a property; especially, the maximum departure of a wave from its average value. Amplitude_Correction Correction Amplitude correction applied to one side of an intersection Amplitude_Difference Amplitude Amplitude difference between two interpretations. Usually, one interpretation is hand-picked and the other one snapped or smoothed (i.e. a slight modification of the first one). Amplitude_Estimate Amplitude Amplitude value on one side of an intersection Amplitude_Kurtosis Kurtosis Kurtosis of seismic amplitude (normalized). Amplitude_Ratio Ratio Ratio of two amplitude values. Amplitude_Skewness Statistical_Skewness Skewness of seismic amplitude (normalized). Amplitude_Standard_Deviation Standard_Deviation Standard deviation of seismic amplitude. Analytic_Trace Acoustic_Amplitude Complex seismic trace resulting from combination of input trace and its Hilbert transform. Normally represented as a pair of floating point numbers. [GeoFrame Value type: Complex32_t] Anchor_Tension Tension Tension of the anchor chains or cables of a marine vessel; may be implemented as a vector. Anelasticity_Factor Coefficient Factor used to compute loss of wave energy due to anelasticity (deviation from a linear proportionality between stress and strain). Loss is computed as exp(-pi * f * Anelasticity_Factor). Angular_Acceleration Data_Valued_Property The rate of change of angular velocity per unit of time. Angular_Dispersion Data_Valued_Property Variation of acoustic velocity with direction, distorting the shape of a wavetrain. Angular_Velocity Data_Valued_Property Rotation rate, usually measured in revolutions per unit time; e.g., spinner speed, motor speed, etc. The term Angular Frequency is also used, but generally refers to data scaled in radians per second. Anhydrite_Volume_Fraction Volume_Fraction The volume fraction of anhydrite with respect to the total volume. Anisotropic_Axis_1_Crossline_Direction Zenith_Angle Angle of first (or only) anisotropic symmetry axis, relative to vertical, measured in the cross-line direction. Axis 1 on its own defines the rotational symmetry axis for transverse isotropy. If accompanied by Axis 2, they together define the symmetry planes for orthorhombic anisotropy. Anisotropic_Axis_1_Inline_Direction Zenith_Angle Angle of first (or only) anisotropic symmetry axis, relative to vertical, measured in the in-line direction. Axis 1 on its own defines the rotational symmetry axis for transverse isotropy. If accompanied by Axis 2, they together define the symmetry planes for orthorhombic anisotropy. Anisotropic_Axis_2_Crossline_Direction Zenith_Angle Angle of second anisotropic symmetry axis, relative to vertical, measured in the cross-line direction. Taken together with Axis 1, Axis 2 is used to define the symmetry planes for orthorhombic anisotropy. Anisotropic_Axis_2_Inline_Direction Zenith_Angle Angle of second anisotropic symmetry axis, relative to vertical, measured in the in-line direction. Taken together with Axis 1, Axis 2 is used to define the symmetry planes for orthorhombic anisotropy. Anisotropy Data_Valued_Property Measure of the variation of a property based upon the direction in which it is measured. Annotation Data_Valued_Property Any annotation (or annotations) pertaining to an object. For example, annotations attached to a Map object. Annual_Payment Money Annual amount of Payment based on some contractual agreement such as a lease. This could be rental, mortgage or other. Annular_Pressure_Data_Density MWD_Data_Density Density of data samples per length of borehole traversed, for an annular pressure measurement. Annulus_Pressure Pressure Pressure of the fluid in the annulus. The annulus is the region outside the subject pipe, such as the region between drill pipe and the formation, or between casing and formation, or between tubing and casing. Annulus_Volume Volume The volume of the portion of the borehole which lies between the borehole wall and the casing. Anti_Collision_Method Method_Type Method used for calculating the proximity: 0 - Normal; 1 - Horizontal; 2 - Least Distance Aperture Width The size of any opening in an otherwise solid wall or surface. The size of a window that limits the information affecting a measuring device. Also used in processing (e.g., seismic migration or deconvolution.) Aperture_Time Time_Interval The time interval which contains the data used in a calculation, usually specified as the start and end times for the aperture. Apparent Modifier Illusory, seeming, appearing as actual to the eye or mind. Apparent_Dip_Angle Dip_Angle Angle between the dip plane and the plane perpendicular to the borehole Apparent_Dip_Azimuth_North Dip_Azimuth In the plane perpendicular to the borehole, viewed from above the tool, angle measured clockwise from the projection of the north direction to the projection of the true dip azimuth. Apparent_Dip_Azimuth_Tool Dip_Azimuth In the plane perpendicular to the borehole, viewed from above the tool, angle measured clockwise from logging tool reference direction to the projection of the true dip azimuth. Apparent_Dip_Azimuth_Top_Of_Hole Dip_Azimuth In the plane perpendicular to the borehole, viewed from above the tool, angle measured clockwise from the top of hole direction to the projection of the true dip azimuth. Apparent_Fluid_Velocity Flow_Velocity Apparent velocity of the fluid. Apparent_Mud_Filtrate_Resistivity Mud_Filtrate_Resistivity Apparent resistivity of the mud filtrate, generally from log measurements of the "flushed zone". Apparent_Porosity Porosity Initial estimate of porosity, normally from logs, not corrected for the (often large) effects of clays, gas, etc. Such estimates should only be used for qualitative interpretation of clean, gas-free intervals. Apparent_Seismic_Polarity Analytic_Trace Sign of trace sample scaled with Reflection_Strength; used for seismic displays. Apparent_Thickness Thickness Layer thickness measurement along the borehole, neither corrected for borehole deviation nor for layer dips Apparent_Velocity Acoustic_Velocity In seismics, the phase velocity which a wavefront appears to have along a line of geophones. Otherwise, the inverse of the slope of a refraction time-distance curve. Apparent_Viscosity Viscosity Ratio Shear Stress/Shear Rate. Equal to Newtonian Viscosity for Newtonian fluid. Apparent_Water_Resistivity Water_Resistivity Apparent resistivity of connate (formation) water, generally from logs; such estimates require correction before they can be used quantitatively. Arc_Type Type The type of Arc objects which bound surface regions of the Earth, e.g. State Boundary, River, etc. Archie_Porosity_Constant Exponent The constant "a" in the Archie formation resistivity factor - porosity relationship. Archie_Porosity_Exponent Exponent The exponent of the Porosity term in the Archie formation resistivity factor - porosity relationship. Abbreviated "m". Array_Code Code Catalog-controlled code of an Array Array_Conductivity Conductivity Formation conductivity as measured by a device capable of taking measurements at various combinations of resolution, depth of investigation, azimuth; such surveys allow detailed investigation of the invasion profile. Array_Induction_Conductivity Array_Conductivity Formation conductivity as measured by an induction device capable of taking measurements at various combinations of resolution, depth of investigation, azimuth; such surveys allow detailed investigation of the invasion profile. Array_Induction_Quality_Indicator Quality_Indicator Property used to indicate quality or confidence of data from an array induction survey. Array_Induction_Resistivity Array_Resistivity Array Resistivity measurement using induction logging principles. Array_Laterolog_Conductivity Array_Conductivity Formation conductivity as measured by a laterolog device capable of taking measurements at various combinations of resolution, depth of investigation, azimuth; such surveys allow detailed investigation of the invasion profile. Array_Laterolog_Resistivity Array_Resistivity Array Resistivity measurement using laterolog (or guard log) resistivity logging principles. Array_Resistivity Resistivity Formation resistivity as measured by a device capable of taking measurements of at various combinations of resolution, depth of investigation and/or in different azimuthal directions. Article_Title Publication_Title Title of article or memo Ash_Volume_Fraction Volume_Fraction The volume fraction of ash with respect to the total volume. Aspect_Ratio Shape Ratio of width to length. Also the ratio of vertical to horizontal scales on a graph, or that of the shorter to longer axes for an ellipse or ellipsoid. Atomic_Number Data_Valued_Property An experimentally determined number characteristic of a chemical element that represents the number of protons in the nucleus which in a neutral atom equals the number of electrons outside of the nucleus and that determines the place of the element in the periodic table. Atomic_Weight Data_Valued_Property The average relative weight of an element referred to some element taken as a standard; basis may be hydrogen with an atomic weight of 1, oxygen with an atomic weight of 16, or carbon with an atomic weight of 12. Attenuation Data_Valued_Property Loss in energy or reduction in sensitivity. In seismic work, loss in acoustic energy due to absorption, reflection, etc. which occurs between any two points of travel. Attenuation_Factor Indicator Coefficient used to quantify the attenuation of a plane wave: a wave traveling a distance X will be reduced by a factor of e**(-AX), where A is attenuation factor. Attenuation_Gain Data_Valued_Property Change in electric potential per unit of attenuation, where attenuation is generally expressed in dB. Attenuation_Rate Data_Valued_Property A measure of the rate of attenuation of a wave per unit length. Attenuation_Resistivity Electromagnetic_Propagation_Resistivity Formation resistivity as measured by the attenuation of a high frequency (hundreds of KHz to several MHz) electromagnetic wave; these measurements are typically deeper than measurements based on phase shift, but their vertical resolution is less sharp and they often cannot be used reliably in high-resistivity formations. Attribute_Name Name Name of an Attribute of an Object Author_Name Person_Name Author of document Authorization_For_Expenditure Identifier Identifier of granted or candidate request for authorization to spend money, usually for a specified purpose and amount. Abbreviated AFE Auto_Exit Processing_Option Flag indicates module is to be automatically stopped when run in chain Auto_Start Processing_Option Flag indicates module is to be automatically started when run in chain Availability Type An indicator of the degree to which data, a product or a service is available for use; used to classify E&P data in order to support filtering of non-essential data from output. Average Modifier The data related to the property is the average of two or more other data sources. Averaging_Interval Interval_Length Length of interval over which data are averaged. Avg_Acoustic_Velocity Acoustic_Velocity Average velocity of an acoustic wave: the distance between two points divided by the travel time of the compressional wave between those points. Avg_Amplitude Amplitude Average (mean) value of amplitude. Avg_Bed_Thickness Thickness Average thickness of a geologic bed. Avg_Compressional_Shear_Velocity_Ratio Compressional_Shear_Velocity_Ratio Time average of compressional-shear velocity ratio from top to reflector. Avg_Density Density Average value of the material density. Avg_Flowrate Flowrate Average Flowrate on a given period of time Avg_Magnitude Magnitude Average (mean) magnitude. Avg_Mode_Converted_Velocity Mode_Converted_Velocity Average converted-wave velocity from the surface to the reflector. The converted wave velocity is determined from the time taken for the energy to travel in one direction as compressional wave and in the other as shear. Avg_Peak_Amplitude Amplitude Average of the amplitudes of waveform peaks. Avg_Penetration_Rate Penetration_Rate Average drilling penetration rate (ROP) Avg_Porosity Porosity Average value of the material Porosity. Avg_Pressure Pressure Pressure averaged on a given time. Avg_Q_Ratio Q_Ratio Average (harmonic mean) value of the compressional wave quality factor. Avg_Qs_Ratio Qs_Ratio Average (harmonic mean) value of the shear wave quality factor. Avg_Reservoir_Pressure Pressure The average pressure (somewhere in the reservoir) between the borehole pressure and external boundary pressure. Avg_Running_Speed Running_Speed Average Speed of equipment running into (counted positive) or out of the hole (counted negative). Avg_Seismic_Energy Acoustic_Energy Energy of seismic trace within window, computed by summing the squares of the amplitude values and dividing by the number of samples summed. Avg_Seismic_Velocity Avg_Acoustic_Velocity Special usage of Avg_Acoustic_Velocity which deals specifically with the velocity between a reference datum near the surface and some subsurface point; often a vertical path is implied and the velocity is computed as depth divided by seismic travel time. Avg_Sequence_Trend Coefficient A coefficient that characterizes the upwards or downwards increasing conductivity trend within a given depth interval Avg_Shear_Compressional_Velocity_Ratio Shear_Compressional_Velocity_Ratio Time average of shear-compressional velocity ratio from top to reflector. Avg_Shear_Velocity Shear_Velocity Average shear wave velocity, from the surface to the reflector. The shear wave velocity is determined from the two-way vertical time taken for the energy to travel to the reflector and back as a Shear wave. Avg_Trough_Amplitude Amplitude Average of the amplitudes of waveform troughs. Avg_Weight_On_Bit Weight_On_Bit Average "Weight On Bit" (WOB) Award_Date Date Date lease awarded Axial_Length Length The length associated with the longest dimension of an object. This corresponds to the height of a cylinder, or the longest axis of a rectangle. Axial_Spacing Length The spacing or distance between two locations on an equipment item; for example, between two sensors on a logging tool. Axis_Azimuth Azimuth Azimuth of the axis, usually pertaining to a depositional environment such as a tidal-flat. Axis_First_Value Multi_Use_Property First value along axis Axis_Index_Code Code Code of axis of n-dimensional data array. Axis_Spacing Multi_Use_Property Spacing or displacement along axis Axis_Unit Unit_Code Unit for spacing and start value on axis. Azimuth Plane_Angle Horizontal angle measured clockwise from true North. (Also referred to as True Bearing.) Occasionally azimuth will be specified relative to some other reference. Azimuth_Error Error Plus or minus azimuth error of sensor Azimuth_Reference_Type Type Type of geographical object used as reference for azimuth measurements: by default, azimuths are referred to True North. Azimuth_Turn_Rate Curvature The rate of change of the azimuth of the borehole, normally expressed in degrees per unit of course length Azimuth_Unit Unit_Code Unit for Azimuth data BHA_Number Identifier An identification number assigned to a bottomhole assembly, normally for tracking purposes at the wellsite. BHA_Run_Number Run_Number Sequence number of the bottomhole assembly (BHA) run. Back_Pressure_Drop Pressure Constant pressure drop on a flowline used mainly to approximate any kind of restriction, choke, nozzle ... Background_Pressure_Trend Pressure Background pressure trend for a horizontal interference test Bad_Hole_Flag Flag Flag indicating that the hole is in poor condition (e.g. oversize or overly rugose) Bale_Kappa Anisotropy Bale's kappa, the mode-converted wave equivalent to eta, describing the relationship between horizontal and moveout mode-converted wave velocities. Bale_Xi Anisotropy Bale's xi, the shear wave equivalent to eta, describing the relationship between horizontal and moveout shear wave velocities. Band_High_Frequency Frequency Upper limit of frequency band (range) Band_Low_Frequency Frequency Lower limit of frequency band (range) Bandwidth Data_Valued_Property Effective frequency range, typically between the half-power points (the frequencies at which the power drops to half of the peak power). Bandwidth is occasionally represented by the central frequency of the band or as the difference between the lower and upper limits of the frequency band, but generally the absolute frequencies should be specified, such as by using Band_Low/High_Frequency properties or by using a complex value type with the Bandwidth property. Bandwidth_Rating_Bias Bandwidth Statistical estimation of bandwidth of data within window. Aids in determining appropriate spectral operators for subsequent operations. Computation: Let the autocorrelation of the trace be A[i]. Then compute M = max(A) and S = sum(A[i]**2). The bandwidth rating bias B is then : B = M**2 / r(2 S - M**2), where r is the sample rate. Bandwidth_Rating_Bias_Wavenumber Wavenumber Bandwidth rating bias in depth domain. See Bandwidth_Rating_Bias Bandwidth_Rating_Debias Bandwidth Statistical estimation of bandwidth of data within window. The bandwidth rating debias D is computed from the bandwidth rating bias B as follows: D = 5/3 B - 1/(s*n), where n is the number of sampled used in the computation. Generally more stable than Bandwidth_Rating_Bias, unless window is small. Bandwidth_Rating_Debias_Wavenumber Wavenumber Bandwidth rating debias in depth domain. See Bandwidth_Rating_Debias Barium_Yield Elemental_Yield Elemental contribution of Barium with respect to total. Barometric_Pressure Pressure The pressure of the atmosphere(relative to vacuum) as measured by a Barometer Base_Fluid_Type Fluid_Type The type of the base fluid usually used in chemical mixing, such Oil or Water. Base_For_Spacing Processing_Option A flag that determines which reference along a Borehole will be used to space Boreholes on a Cross Section. Base_Latitude Latitude Latitude value used as the basis or starting point, such as in a multiple regression computation. Base_Longitude Longitude Longitude value used as the basis or starting point, such as in a multiple regression computation. Baselap_Type Type The type of a Baselap in the Earth subsurface, whether it is an Onlap or a Downlap Battery_Code Code Code for the recorder battery Battery_Life Time_Interval Battery Life Battery_Type Type Recorder battery type Battery_Weight Weight Battery Weight Baud_Rate Frequency The net speed at which data are transmitted. Bearing Plane_Angle The horizontal angle between the direction to a point and the direction of some reference line, normally measured as a clockwise angle from the reference line. Bearing_Type Type Type of bearing, such as sealed or mud lubricated Beaufort_Scale_Number Wind_Velocity The Beaufort wind scale is a system used to estimate and report wind speeds when no measuring apparatus is available. It was invented in the early 19th century by Admiral Sir Francis Beaufort of the British Navy as a way to interpret winds from conditions at sea, e.g. 5 on the Beaufort scale corresponds to a wind of 17-21 knots and is defined as "Fresh Breeze: Moderate waves (1.8m), many white horses." Bed_Character Type The Characteristic given to a Bed or layer (e.g. has sealing characteristic or is probable source rock.) Bed_Set_Type Type The type of bed grouping Bed_Type Type The general physical and structural character or pattern of beds and their contacts within a rock mass; e.g., cross-bedding and graded bedding; homogenous, wave ripples, planar cross beds. Begin_Element Ordinal_Number The number of the first element, usually in an array or along an axis. Begin_Time Absolute_Time Time at which a process began Bend_1_Angle Plane_Angle Angle of first bend in equipment item. Bend_1_Bend_2_Angle Plane_Angle Angle between the planes defined by the first and second bends in the equipment string. Bend_1_To_Bottom_Conn Length Length from the first bend to the bottom connection of the tool Bend_2_Angle Plane_Angle Angle of second bend in equipment item. Bend_2_Bend_3_Angle Plane_Angle Angle between the planes defined by the second and third bends in the equipment string. Bend_2_To_Bottom_Conn Length Length from the second bend to the bottom connection of the tool Bending_Moment_Per_Length Data_Valued_Property For a rotating body, the product of force and length of angular displacement normalized for the radius of rotation. Bid_Amount Money Amount of lease bid Bid_Number Identifier Bid number assigned by governing agency Bin_Porosity Apparent_Porosity Contribution of porosity from a given "bin" (with certain characteristics) to the total porosity; e.g., in nuclear magnetic resonance data processing, the "bins" typically correspond to different pore size ranges. Biological_Name Name A name used for classifying items in a biological taxonomy. Biot_Coefficient Coefficient The proportion of fluid pressure in a material which acts to counterbalance overburden pressure. Used in the calculation of net overburden: P_eff = P_overburden - (Biot_Coefficient * P_fluid). Biotite_Volume_Fraction Volume_Fraction The volume fraction of biotite with respect to the total volume. Bioturbation_Type Type The type of Bioturbation: the mixing of sediments by burrowing organisms. Bit_Bladed_Flag Flag Flag indicating that the bit is a bladed type (PDC type bit). Bit_Depth Depth Depth of the drillbit Bit_Inclination Hole_Deviation Inclination of the drillstring as measured as the bit Bit_Number Identifier An identification number assigned to a drill bit, normally for tracking purposes at the wellsite. Bit_Operating_Time Operating_Time Operating time of the bit over the reporting period. Bit_Profile Type Profile of the bit (PDC type bit) Bit_Rate Frequency The number of bits that may be transported, say via telemetry, per unit time. Bit_Rotation_Speed Angular_Velocity Rotational speed of the Drill Bit Bit_Run_Number Run_Number Sequence number of the bit run. Blade_Gauge_Length Length Length of the in-gauge portion of the blade. Blade_Height Length Height of blade at gauge from the body of the equipment, such as a stabilizer. Blade_Length Length Length of blade measured along spiral; used for drill stabilizer blades. Blade_Material Material_Type Material used in the blade, such as steel, aluminum or plastic. This material represents material of sleeve structure in sleeve type stabilizers and is the same as the body material in integral stabilizers. Blade_Spiral Plane_Angle Degree of spiral blade coverage 0, 270, 450, -270. (0-straight blade; Negative-left spiral; Positive-right spiral) Blade_To_Conn_2 Length Distance from blade to Connection 2. Blade_Width Width Width of the blade at gauge, as used for drill stabilizer blades. Bladeface Plane_Angle In directional drilling, the angle between a (sensor-bearing) stabilizer blade and a fixed reference, measured in a plane normal to the drillstring. In near-vertical applications, North is the fixed reference (Magnetic_Bladeface); for higher deviation applications, Top of Hole is the reference (Gravity_Bladeface). Blocking_Method_Type Method_Type Blocking method Boat_Type Type Supply boat, tanker, dynamic positioning vehicle etc. Bob_Number Ordinal_Number Bob number. The bob is the inner cylinder of a cylindrical rheometer. Each number corresponds to a different size. Standard bob is #1 Body_Material Material_Code Material used in the body such as steel, aluminum, monel Boiling_Point Temperature The temperature at which fractions of a liquid boil. Bore_Count Count Number of bores, as in a production packer. Bore_Inside_Diameter Inside_Diameter The inside diameter of the equipment bore. Bored_Flag Flag Flag to indicate that equipment item has been bored. Borehole_Diameter Inside_Diameter The inside diameter of a borehole. Borehole_Neutron_Capture_Cross_Section Neutron_Capture_Cross_Section The macroscopic neutron capture cross section, i.e. the effective cross sectional area per unit volume, of the borehole environment; used to correct "Sigma" log measurements for borehole effects. Borehole_Radius Radius Radius of the open borehole. Normally taken as the radius of the drillbit. Borehole_Salinity Salinity Salinity of the fluid in the borehole. Borehole_Status Status A property indicating current status of a Borehole: Producing, Abandoned, etc. Related to the Petroleum Information (PI) codes. Borehole_Temperature Fluid_Temperature Temperature of the material in the borehole. Borehole_Volume Volume The volume of the borehole. Boron_Yield Elemental_Yield Elemental contribution of Boron with respect to total. Bottom_Depth Depth The deepest depth of a borehole interval, a formation, or any depth indexed representation of a data item. Bottom_Dip_Number Dip_Number Number of Dip (in the Dip Set) at the bottom of the Bed Bottom_Discontinuity_Type Discontinuity_Type Type of Discontinuity forming the bottom boundary. Bottom_Location Location The location of the Bottom of any Entity with a geometric extent (e.g., Zone Interval, Borehole, Borehole Segment, Rig, Arc, Edge, etc.). It is represented by some position relative to a coordinate system. Bottom_Subsea_Vertical_Depth Subsea_Vertical_Depth Subsea Vertical Depth of Bottom of Interval Bottom_True_Stratigraphic_Thickness_Depth True_Stratigraphic_Thickness_Depth True Stratigraphic Thickness Depth of Bottom of Interval Bottom_True_Vertical_Depth True_Vertical_Depth True Vertical Depth of Bottom of Interval Bottom_True_Vertical_Thickness_Depth True_Vertical_Thickness_Depth True Vertical Thickness Depth of Bottom of Interval Bottom_Two_Way_Time Two_Way_Time Depth of Bottom of Interval in Two Way Time Bottom_Value Multi_Use_Property Value at the bottom of an interval. Bottom_Vertical_Section Vertical_Section Bottom "depth" of an interval along a Vertical Section (VSCT) index. Bottomhole_Circulating_Pressure Bottomhole_Pressure The pressure at the bottom of a borehole during circulation of any fluid. Bottomhole_Circulating_Temperature Bottomhole_Temperature The bottom hole temperature reached when circulating. Due to the cooling effect of the drill fluid, BHCT is below the BHST. Bottomhole_End_Type Type Indicates what limits the total depth (plug back, borehole bottom, bridge plug, sump packer ...) Bottomhole_Flowing_Pressure Bottomhole_Pressure Flowing pressure inside the wellbore at midpoint of the completed interval. Res. Eng. Pwf Bottomhole_Flowing_Temperature Bottomhole_Temperature Temperature at the bottom of the well while flowing. Bottomhole_Mud_Resistivity Mud_Resistivity Resistivity of the mud at Bottomhole Conditions Bottomhole_Pressure Pressure The pressure at the bottom of a borehole generally associated with the pore pressure of the formation open to the well. Bottomhole_Shutin_Pressure Bottomhole_Pressure The pressure at the bottom of a borehole with the well shut in. Bottomhole_Static_Temperature Bottomhole_Temperature The bottom hole equilibrium temperature (when circulation is stopped) Bottomhole_Temperature Temperature The temperature at the bottom of a borehole occurring at the time of the activity being performed on the well. Bound_Water_Conductivity Conductivity Conductivity of water bound to clay in the formations. Bound_Water_Resistivity Resistivity Resistivity of water bound to clay in the formations. Bound_Water_Saturation Saturation The extent to which the pore space in a formation contains bound water. Bound_Water_Volume_Fraction Water_Volume_Fraction The volume fraction of bound Water with respect to the total volume. Boundary_File File_Name Name of file containing boundaries Boundary_Type Type The type of a Boundary in the Earth subsurface, e.g. Facies Boundary, Sequence Boundary, etc. Bowl_Speed Centrifuge_Speed The bowl speed of a centrifuge. Box_Number Identifier Number of box in which an item or sample is stored. Breakdown_Pressure Pressure The pressure required to create a hydraulic fracture in an unfractured formation; it is greater than fracture closure pressure except in rare cases, such as very low fracture toughness and very large horizontal stress anisotropy. Bubble_Flow_Velocity Flow_Velocity The rate at which a fluid bubble, gas or liquid, flows through another fluid, gas or liquid. The Velocity depends on the densities and viscosities of the fluids. Bubble_Point_Pressure Pressure The pressure at reservoir temperature at which gas in solution in crude oil comes out of solution as free gas. Bubble_Point_Temperature Temperature The temperature at reservoir conditions at which gas in solution in crude oil comes out of solution as free gas. Bubble_Size Diameter Diameter of the bubbles of non-continuous production phase. Buildup_Pressure Pressure Pressure recorded in the borehole at downhole conditions during a pressure buildup test. Bulk_Addition_Mode Type Describes how the bulk material was added to the mixture. Bulk_Density Density Density of bulk material, including any void space or other materials contained in the subject volume. In well logging, it is the density of the rock, including fluid-filled pore space, as measured with a "Gamma-Gamma" type logging device. Bulk_Density_Correction Correction Correction to the Bulk Density log, as measured with a Gamma-gamma type logging device; used as an indication of hole condition to validate the Bulk_Density measurement; conventionally abbreviated DRHO. Bulk_Modulus Elastic_Modulus The stress-strain ratio under simple hydrostatic pressure. k = Delta-P / (Delta V / V), where Delta-P, -V denote the change in Pressure and Volume. Burner_Code Code Code for burner equipment Burner_Head_Count Count Number of heads of the burner (conventionally, 3,4 or 6) Burner_Pilot_Pipe_Size Diameter Standard gas pipe size connection supplied on the pilot inlet equipment Burner_Type Type Type of burner Burst_Pressure Pressure Burst Pressure. Business_Associate_Job_Title Type The assignment of an administrative job title to a business associate in the context of a business association Business_Line Data_Valued_Property Group of activities or services gathered by some commonalities Business_Line_Code Code MIS Code of the business line Business_Region_Type Type The type of a Business defined region of the Earth surface, e.g. Field, Lease, Concession, etc. Byte_Count Count Total number of bytes used or required by a collection of data. C2H6_Concentration Chemical_Concentration Concentration of C2H6 by volume. Typical value in natural gas 6%. C3H8_Concentration Chemical_Concentration Concentration of Propane (C3H8); typical volume concentration in natural gas is 2%. C4H10_Concentration Chemical_Concentration Concentration of Butane (C4H10). C5H12_Concentration Chemical_Concentration Concentration of Pentane (n-C5H12). C6H14_Concentration Chemical_Concentration Concentration of Hexane (C6H14); typical volume concentration in natural gas is 0.3%. C7H16_Concentration Chemical_Concentration Concentration of Heptane (C7H16) C7plus_Concentration Chemical_Concentration Concentration of Heptane and hydrocarbons heavier than Heptane; typical volume concentration in natural gas is 0.5% C7plus_Plus_Molecular_Weight Molecular_Weight Molecular weight of Heptane (C7H14) and heavier component concentration in crude oil. Typical value: 110-130 C7plus_Specific_Gravity Specific_Gravity Specific Gravity versus air at standard conditions of the Heptane (C7H14) and heavier component found in crude oil CBL_Quality_Indicator Quality_Indicator Property used to indicate quality or confidence of data from a Cement Bond logging survey. CCP_Trajectory Trajectory List linking shots and receivers to Common Conversion Points (CCP) in depth. Defines the trajectory in shot-offset domain to stack along to image a point in depth. CH4_Concentration Chemical_Concentration Concentration of Methane (CH4); typical volume concentration in natural gas is 85%. CO2_Concentration Chemical_Concentration Concentration of Carbon Dioxide (CO2) CO2_Foam_Quality Ratio Ratio volume of CO2 over foam volume. Indicator of the quality of a foam generated with CO2 for well treatment. Below 50% the foam is not stable, above 95% the foam changes to a mist. C02 foam are used when low pH is required. CO2_Mole_Fraction Mole_Fraction Mole fraction of Carbon Dioxide to total gas composition CO_Concentration Chemical_Concentration Concentration of Carbon Monoxide (CO) CS_Trans_Type Type The type of Transformation used between 2 coordinate systems, e.g. Molodensky, Affine 2D, etc. CaCl2_Concentration Chemical_Concentration CaCl2 concentration. Cable_Length Length Cable length; measured from a fixed reference point and used as Measured Depth in Wireline operations Cable_Speed Velocity Cable speed, generally measured at the surface as an approximation of tool speed. Cable_Type Type Type of cable. Calcite_Volume_Fraction Volume_Fraction The volume fraction of calcite with respect to the total volume. Calcium_Concentration Chemical_Concentration Calcium concentration (Water Based Mud and water phase for Oil Based Mud) Calcium_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of calcium to total dry weight Calcium_Yield Elemental_Yield Elemental contribution of Calcium with respect to total. Calibrated Modifier A calibration process has been applied to the data related to the property. Calibration_Coefficient_Code Code Calibration coefficient code. Calibration_Date Date Date of calibration for the equipment; time may also be included. Calibrator_Type Type Type of device used to calibrate the sensor or tool. Caliper Borehole_Diameter Borehole diameter as measured by a logging device: a record of the borehole or the internal diameter of tubular goods. Capacitance Data_Valued_Property The ratio of the charge on a capacitor to the electric potential across it. Capacitive_Reactance Reactance The component of electrical impedance due to capacitance: Xc = 1 /(2 pi F C), where F is the frequency and C is the capacitance. Capillary_Number Ratio The ratio of capillary to viscous forces on fluids in a porous media. Capillary_Pressure Pressure The difference in pressure between two phases, air fluid, gas fluid or between two fluids, measured at points of the interconnected phases. Capillary_Pressure_Function Function_Name Name of the function used to represent capillary pressure. Capillary_Pressure_Function_Coeff Coefficient Coefficients used in the capillary pressure function. Capillary_Transition_Zone_Height Height The vertical interval height that describes the transition between two different fluid phases in a porous media. This transition is caused by changes in saturation dependent capillary forces in equilibrium with gravitational forces. Carbon_Oxygen_Ratio Ratio Ratio of relative abundance of Carbon to that of Oxygen; important for hydrocarbon detection and saturation determination because it is independent of salinity. Carbon_Volume_Fraction Volume_Fraction The volume fraction of carbon with respect to the total volume. Carbon_Yield Elemental_Yield Elemental contribution of Carbon with respect to total. Carbonate_Volume_Fraction Volume_Fraction The volume fraction of carbonate rock with respect to the total volume. Cardinality Count Number of instances of an Entity type which may be referred to by another Entity in a particular relationship; may be ONE or MANY. Casing_Collar_Locator Indicator Signal from a device which indicates the presence of a casing or tubing collar, used for depth control in logging operations. Casing_Grade Steel_Grade Casing pipe grades given to material properties that fall within the tolerances set by API specifications; e.g., J55, K55, H40, etc. Casing_Inside_Diameter Inside_Diameter Casing inner diameter Casing_Outside_Diameter Outside_Diameter Casing outer diameter Casing_Rotation_Friction_Coefficient Friction_Coefficient Friction coefficient due to rotation between casing and other surface (e.g. drill string). Casing_Shoe_Depth Depth Casing shoe depth Casing_Sliding_Friction_Coefficient Friction_Coefficient Friction coefficient due to sliding between casing and other surface (e.g. drill string), when only sliding motion is present Casing_Translation_Friction_Coefficient Friction_Coefficient Linear component of the friction coefficient between casing and drill string during an helical movement, e.g., reaming mode Casing_Type Type Type of casing or tubing used, such as riser, conductor, intermediate, liner, surface, tubing, production, etc. Casson_Plastic_Viscosity Plastic_Viscosity Measure of the internal resistance to fluid flow attributable to the amount, type, and size of solids present in a given fluid. The Casson model equation is: SQRT(Shear_Stress) = SQRT(Yield_Stress) + SQRT(Plastic_Viscosity X Shear_Rate) Casson_Yield_Stress Yield_Stress Resistance to initial flow; the stress required to start fluid movement. The Casson model equation is: SQRT(Shear_Stress) = SQRT(Yield_Stress) + SQRT(Plastic_Viscosity X Shear_Rate) Catalog_Code Entity_Code Code of the catalog entity providing further specifications of the leaf entities of a certain entity type. Cation_Concentration Chemical_Concentration The concentration of cations, the positively charged particles, in the solution of an electrolyte. Cation_Exchange_Capacity Data_Valued_Property A measure of the extent to which a substance will supply exchange cations. Cell_Count Count Number of cells Cement_Additive_Type Type Type of additive(s) used to change the properties of the cement. Cement_Bond_Amplitude Acoustic_Amplitude A measure of acoustic wave amplitude used for cement bond evaluation. Cement_Bond_Index Indicator The ratio of acoustic wave attenuation in a zone of interest to that measured in a well-cemented section of casing, used as an indication of the quality of a casing cement job. Cement_Density Density The density or weight per unit volume of cement (or cement slurry). Cement_Retarder_Type Type Type of material used to retard the setting of the cement. Cement_Sheath_Thickness Thickness Thickness of the cement sheath between casing and borehole wall. Cement_Type Type Type of cement Cement_Unit_Discharge_Pressure Pressure Cementing unit maximum discharge pressure Cement_Unit_Output Flowrate Cementing unit maximum output flowrate Cement_Unit_Power Hydraulic_Power Cementing unit input horse power Cement_Unit_Type Type Cementing unit type Cement_Volume Volume Volume of cement. Cementitious_Flag Flag Flag indicating if the chemical is accounted for as a cement when proportioning by weight of blend. Cementitious chemicals are mostly weight extenders like bentonite. Central Modifier Containing or constituting a center. Central_Frequency Frequency Central frequency within power spectrum; average of the low and high frequencies of the band. Central_Line_Bearing Azimuth Azimuth of central line of projection. Central_Line_Pt1_Latitude Latitude Latitude of first point on central line of projection. Central_Line_Pt1_Longitude Longitude Longitude of first point on central line of projection. Central_Line_Pt2_Latitude Latitude Latitude of second point on central line of projection. Central_Line_Pt2_Longitude Longitude Longitude of second point on central line of projection. Central_Line_X_Alignment Flag Alignment of central line x-coordinate: 0 if central line is x-axis, 1 if x-axis is east west Central_Meridian Longitude The meridian on a graticule that is the axis of symmetry for the geometric properties of the graticule displayed on a map projection. Central_Wavenumber Wavenumber Central frequency in the depth domain Centralizer_Code Code Centralizer Code Centralizer_Count_Per_Joint Count Number of centralizers per joint, e.g. 2 per joint. Centralizer_Outside_Diameter Outside_Diameter Centralizer outside diameter Centralizer_Test_Type Type The type of a Centralizer Test used to test a centralizer, usually during any well operation. Centralizer_Type Type The type of a Centralizer used to center a casing, a tubular, or a logging tool in the center or near the center of the borehole, aligned with the borehole axis. Centrifuge_Speed Angular_Velocity The bowl speed of a centrifuge. Cesium_Concentration Concentration Concentration of Cesium. Channel_Width Width The perpendicular distance between two parallel boundaries. Chemical_Concentration Concentration The concentration of a chemical usually used during well operations, like drilling, cementing, acidizing, fracturing, etc. Chemical_Formula Formula A symbolic expression of the composition or constitution of a substance. Chemical_Function Type Primary purpose of a chemical e.g. Corrosion_Inhibitor, Gelling_Agent, Retarder, Emulsifier, ... Chemical_Product_Type Type The type of a Chemical Product used in various types of activities, usually those provided by Dowell-Schlumberger Chemistry_Type Type Type of chemical system. Chi_Square Statistical_Property Statistical test of data distribution, used to measure goodness of fit of the data to some distribution model. Chloride_Concentration Chemical_Concentration Concentration of chloride ions in water based mud or in the water phase of oil based bud Chlorine_Yield Elemental_Yield Elemental contribution of Chlorine with respect to total. Chlorite_Volume_Fraction Volume_Fraction The volume fraction of chlorite with respect to the total volume. Choke_Manifold_Code Code Code for the choke manifold Choke_Manifold_Type Type Type of choke manifold Choke_Size Inside_Diameter Internal diameter of the flow choke(s) Choke_Working_Pressure Working_Pressure Working pressure of the choke box which allow for the well fluid flow to be controlled by varying the flow cross-sectional area Circulating_Line_Pressure Pressure Pressure observed at circulating line/BOP Circulating_Pressure Pressure Fluid pressure under circulating conditions. Circulation_Loss_Depth Depth Depth at which circulation is being lost to the formation. Circulation_Loss_Rate Flowrate Rate of loss of drilling fluid to the formation, due to mud density exceeding formation fracture pressure gradient, and/or to drilling through a highly permeable formation. Classification Type Systematic arrangement in groups or categories according to established criteria. Classification_Group_Code Type Associates class definitions into one family: Generic, Unsupervised, Pore_Fluid, Lithologic, Seismostratigraphic, Texture, User_Defined_Mix, User_Defined_No_Mix. Classification_Index Explicit_Index Index into a lookup-table describing various classifications. Typical usage is a surface representation (grid) of index values, where each value represents a particular classification. Classification_Method_Code Method_Type Classification method used in this activity. Classification_Method_Type Type The type of method used for classification: e.g. Statistical, Artificial Neural Net, or Clustering. Classification_Scope Type Per Method expects a maximum of one parameter instance per classification activity. Per Class expects a maximum of as many parameter instances as classes were involved in the classification activity. Clay_Resistivity Resistivity The Resistivity of clay, usually referring to that measured in the Earth formations. Clay_Volume_Fraction Volume_Fraction Volume fraction of clay as calculated, measured or inferred from formation properties. Client Organization_Code The code of a client, usually that of a Service, Contractor, Vendor or E&P company Client_Representative Person_Name Name of the client representative or company man. Closure Flag Indicates whether the boundary of a spatial object is Open or Closed? Coal_Volume_Fraction Volume_Fraction The volume fraction of coal with respect to the total volume. Cobalt_Concentration Concentration Concentration of Cobalt. Code Data_Valued_Property The code, mnemonic, or identifier used to enumerate types, occurrences, or instances of some property or entity. Code_In_Catalog Flag Flag to indicate that the Code is available in a Catalog. Coefficient Data_Valued_Property A number which serves as a measure of some characteristic of a process, substance or device. Coherence Data_Valued_Property A measure of the similarity between two or more functions; used with seismic waveforms to distinguish seismic events and to implement automatic picking schemes. Coil_Tubing_Section Ordinal_Number Number of the Coiled Tubing section used by the CoilLIFE module. Collapse_Pressure Pressure Collapse Pressure. Color Data_Valued_Property The aspect of objects and light sources that may be described in terms of hue, lightness, and saturation for objects and hue, brightness, and saturation for light sources. Color_Distribution Color A descriptive remark with respect to the distribution of a color within the area of a rock surface; e.g. solid, spotty, streaky. Color_Fluorescent_Light Color The color emitted by the fluid upon exposure to fluorescent light. Certain photoactive hydrocarbon molecules display characteristic color patterns under these conditions. Color_Intensity Color A descriptive comment with respect to the intensity of color; e.g. bright, dull, powdery. Color_Map Color Name of entity which maps from Implementation index values to color; GPD_COLOR_MAP arrays are commonly used. Color_Normal_Light Color The color of a hydrocarbon show under normal incident light. Column_Name Name Name of a Column in a database Table. Companion_Data Data_Valued_Property Collection to hold miscellaneous competitor data in any form (parameters, arrays, ...), not described in the Data Model Company Organization_Code The code of a Company, usually that of a Service, Contractor, Vendor or E&P company Company_Lease_Number Identifier Unique lease number assigned by owning company Company_Type Type The type of a Company, e.g. E&P, Service, Contractor, Vendor, etc. Compartment_Count Count Number of independent storage units Compass_Bearing Azimuth The azimuth of an object with respect to magnetic north. Completed_Thickness Thickness Thickness of hydraulic unit actually contributing to the production. Completion_Count Count The count of the number of completions. Completion_Date Date Date that the activities that created the wellbore were completed and the wellbore was available to produce gas or oil, or for other intended service (e.g. gas storage, geothermal, etc.). Common completion activities include running and cementing the "production string" of casing, perforating the casing and cement sheath, installing the production string (tubing, packers, etc.) and the wellhead, etc. Completion_Skin Skin_Factor Skin effect due the completion of the producing interval. It does not include the effect of partially completed interval (plugged perf or bad localization), but it does include Gravel Pack skin. Completion_Type Type Type of well completion. Compliance Data_Valued_Property The relationship of strain to stress, a tensor quantity expressible as the inverse of the stiffness matrix. Component_1_Name Name Name of first component in a mixture or composition. Component_2_Name Name Name of second component in a mixture or composition. Component_3_Name Name Name of third component in a mixture or composition. Component_4_Name Name Name of fourth component in a mixture or composition. Compressibility Data_Valued_Property The change in specific volume and density under pressure; the reciprocal of Bulk Modulus, 1/k. Compression_Pressure Pressure The pressure applied to compress a body or material, as opposed to that applied by tension. Compressional_Shear_Velocity_Ratio Ratio Ratio of velocity of Compressional wave (Vp) to that of Shear wave (Vs). Compressional_Slowness Acoustic_Slowness The time it takes for a compressional wave to traverse a fixed distance; reciprocal of Compressional_Velocity. Compressional_Velocity Acoustic_Velocity Velocity of a compressional acoustic wave (Vp). Compressional_Velocity_Gradient Gradient A measure of the change in the compressional velocity of a medium per unit length. Compressive_Force Force The force tending to compress or squeeze a body. Compressive_Strength Strength The degree of resistance of a material to force acting along one of the axes in a manner tending to crush it. Computation_Mask Data_Mask Application-specific mask for the computation options (one Anadrill example: 0001 - Torque & Drag, 0010 - BHA Tendency, 0100 - Bit Side Forces, 1000 - Buckling, 10000 - Yield Stress) Computation_Type Method_Type Computation method used in the generation of data. Computed Modifier The data related to the property is an output of a process (e.g., Software Module), usually based on input data from a single source. Concentration Data_Valued_Property The relative content of a component; e.g., the concentration of salts in brackish water, the concentration of electric charges in a circuit, etc. Concentration_1 Concentration Concentration or proportion of first component in mixture or other composition. Concentration_2 Concentration Concentration or proportion of second component in mixture or other composition. Concentration_3 Concentration Concentration or proportion of third component in mixture or other composition. Concentration_4 Concentration Concentration or proportion of fourth component in mixture or other composition. Condensate_Flowrate Flowrate Rate of flow of condensate Conductance Data_Valued_Property The readiness with which a material conducts electric current; the inverse of resistance. Also, the product of conductivity and thickness. Conductive_Bed_Proportion Proportion Percentage of rock occupied by conductive beds within a given depth interval Conductive_Inclusion_Contrast Conductivity_Contrast Conductivity contrast between conductive inclusions and the surrounding rock Conductive_Inclusion_Proportion Inclusion_Proportion Percentage of rock occupied by conductive inclusions within a given depth interval Conductive_Inclusion_Size Surface_Area Average area of conductive inclusions as seen at the borehole wall Conductivity Data_Valued_Property A measure of the quantity of electricity transferred across unit area per unit potential gradient per unit time. In isotropic material, it is the reciprocal of Resistivity. Sometimes called Specific Conductance. Conductivity_Contrast Ratio Conductivity ratio between geological objects Confidence_Factor Indicator The probability that a given event will occur or that a given data set will contain a specified element. Confidentiality_Level Type Describes the confidentiality of the information related to the well, e.g., Tight (operator only), Sensitive (some restriction), Public Conicity Shape The solid angle measuring the degree of resemblance of a solid to a cone especially in shape. Conn_1_Approx_Weight Weight Approximate weight joint/connection 1 Conn_1_Box_Flag Flag Flag indicating if connection is a box (Y) or a pin (N). Conn_1_Drift_Diameter Drift_Diameter Drift diameter of tool joint/connection 1 Conn_1_Inside_Diameter Inside_Diameter Inside diameter of tool joint/connection 1 Conn_1_Nom_Length Length Nominal length of joint/connection 1 Conn_1_Outside_Diameter Outside_Diameter Outside diameter of tool joint/connection 1 Conn_1_Size Outside_Diameter Size of the top or the first standard tool connection. Conn_1_Thread_Type Thread_Type Complete and non ambiguous identification of the first threaded connection, e.g., "Hydril Joint Type EIU", "Pittsburgh Special ACME-Thread Casing-Internal-upset" Conn_1_Type Type Type of the top or the first standard tool connection. Conn_2_Approx_Weight Weight Approximate weight joint/connection 2 Conn_2_Box_Flag Flag Flag indicating if connection is a box (Y) or a pin (N). Conn_2_Drift_Diameter Drift_Diameter Drift diameter of tool joint/connection 2 Conn_2_Inside_Diameter Inside_Diameter Inside diameter of tool joint/connection 2 Conn_2_Nom_Length Length Nominal length of joint/connection 2 Conn_2_Outside_Diameter Outside_Diameter Outside diameter of tool joint/connection 2 Conn_2_Size Outside_Diameter Size of the bottom or second standard tool connection. Conn_2_Thread_Type Thread_Type Complete and non ambiguous identification of the second threaded connection, e.g., "Hydril Joint Type EIU", "Pittsburgh Special ACME-Thread Casing-Internal-upset" Conn_2_Type Type Type of the bottom or second standard tool connection. Conn_Material Material_Code Connection material such as steel, aluminum, plastic Conn_Tensile_Yield Tensile_Yield Maximum force which can be applied to a joint/connection/thread without causing permanent deformation. Conn_Torsional_Yield Torsional_Yield Maximum torque which can be applied to the joint/connection/thread without causing permanent deformation. Connectedness_Coefficient Indicator A coefficient describing the connectedness of items, such as the connectedness between inclusions (e.g. lenses) in the Earth subsurface formations. Connector_Type 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 F J-P, Atbrad FL-3S, etc. Consistency_Index Coefficient The k parameter in the Power-Law and Herschel-Bulkley rheological models. The Power_Law model is "Shear_Stress=k times (Shear_Rate at the power of n)". The unit of k is traditionally lbf.sec^n/ft^2 or Pa.s^n. Constraint_Code Code Key Attribute of Object which constrains the Property values. For example, the Domain Attribute in the String_Enum_Cat used to constrain a string-valued Property. Constraint_Object Object_Name Name of Object holding descriptions of the constraints (e.g. String_Enum_Cat) Constraint_Type Type Type of constraint. Examples include UNCONSTRAINED, STRING_ENUM, INTEGER_ENUM, INTEGER_RANGE, FLOAT_RANGE, DATE_RANGE, ENTITY_CLASS, CATALOG_ATTR, etc. Construct Type Construct specifies how instances of the given Value Domain are assembled into a single Value. Together Value Domain and Construct are used to derive Value_Type. Construct can be null (for a single value), L (for List), V (for Vector) , LL (List of Lists) , VL, PL, etc. Contact_Symbol Identifier Symbol to post on the Feature_Boundary at the intersection point with another Feature_Boundary Contact_Throw_Sense Type Specify whether contact corresponds to upthrown or downthrown portion of fault. Contact_Type Type The type of contact or interface between Earth subsurface regions Container_Code Code Code of containing object Contract_Number Identifier Identifying string for contractual agreement Contract_Status Status Status of a contract. Contractor Organization_Code The code of the contractor, usually a company. Contractor_Representative Person_Name Name of the representative of the Contractor Company Coolant_Temperature Temperature Temperature of the cooling fluid Coord_Sys_Transform_Code Code Code for a coordinate system transform method. Coordinate Length Any coordinate of a Location. Copper_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of copper to total dry weight Copper_Yield Elemental_Yield Elemental contribution of Copper with respect to total. Copy_Number Sequence_Number Number used to identify an instance of a particular type object within a set. Core_Box_Count Count The number of core boxes containing samples from a cored borehole interval in a particular well. Core_Date Date Date on which the core was recovered. Core_Diameter Diameter The Diameter of the recovered core. Core_Preparation_Method Preparation_Method Method by which a core sample has been prepared for analysis. Core_Preservation_Method Preservation_Method Method by which a core sample has been preserved. Core_Type Type Identifies the type of core sample, such as Main, Plug, Slab, Sidewall, etc. Coring_Fluid_Type Fluid_Type The type of fluid that was in the borehole at the time the coring operation was in progress; e.g. water, brine, oil, mud, etc. Coring_Method Type The type of method used to acquire a core sample; e.g. Rotary Conventional, Rotary Sponge, Sidewall Mechanical, etc. Corrected Modifier Generic modifier indicating that data have been corrected and are ready to be analyzed. In practice, many different types of corrections may be applicable. Corrected_Depth Depth Depth which can be offset and scaled from the raw depth acquired from a sensor to take into account the position or deformation of the sensor thus the name of corrected. Correction Data_Valued_Property Correction applicable to a measurement, to remove environmental effects or measurement errors; the unit quantity is determined by that of the data. Correction_Factor Coefficient Coefficient used to correct data, such as for environmental effects. Correlation_Coefficient Indicator Coefficient of a correlation used to determine the quality of the correlation Correlation_Depth_Dip Depth_Dip Dip of seismic data, similar to Depth_Dip but gradient derived from the seismic data (in depth) Correlation_Time_Dip Time_Dip Dip of seismic data, similar to Time_Dip but gradient derived from the seismic data in time) Corridor_Stack Acoustic_Amplitude A summation of the traces in an upgoing Vertical Seismic Profile that have been processed to retain only primary reflection events and that have been time-shifted to their two-way arrival times at the surface. Summation is over a data window (corridor) beginning at the first break time and usually ending 200-300 ms later. Corrosion_Indicator Indicator Any of several measurements which show that material has been damaged by corrosion. Corrosion_Rate Velocity The rate at which corrosion, a complex chemical or electrochemical process by which metal is destroyed, occurs. For example the rate at which a casing pipe rusts (corrodes). Corrosive_Fluid_Flag Flag Is the fluid corrosive? (Y/N) Used to apply a wall erosion model to measure the pipe wall thickness. Cosine_Of_Phase Analytic_Trace Cosine of Instantaneous Phase, also known as normalized seismic amplitude Cost Money Amount of money spent to obtain goods or services. Cost_Charge_Type Type Indicates whether the cost allocation is valid for the start (Start), end (End) of activity or at a given date (User) Cost_Per_Depth Cost Amount of money per unit of length Cost_Per_Mass Cost Amount of money per unit of mass Cost_Per_Volume Cost Amount of money per unit of volume Coulomb_Friction_Coefficient Friction_Coefficient Ratio of contact and friction forces between 2 materials in dry friction conditions i.e. without lubrication (Coulomb law) Count Data_Valued_Property A number indicating the number of occurrences of something. Count_Rate Frequency The number of events per unit time; e.g. the output of a scintillation counters. Counterion_Conductivity Data_Valued_Property The equivalent conductivity of the counterions (cations) in the diffuse layer around clay particles; ratio of conductivity to cation concentration. Refer to Waxman-Smits, Dual-Water models. Country_Code Geopolitical_Region_Code Catalog-controlled code of a Country. Country_Name Name Name of a Country County_Code Geopolitical_Region_Code Catalog-controlled code of a County or Parish. County_Name Name Name of a County or Parish Covariance Statistical_Property A measure of the common variance between two quantities; a non-normalized crosscorrelation function. Create_Date Date Date of creation of a data item in the database. Critical_Angle Plane_Angle Angle of incidence for which a refracted ray follows the surface of contact between two media of different velocities. Critical_Distance Seismic_Offset In seismic work, the offset at which the reflection time equals the refraction time. Critical_Drawdown_Pressure Drawdown_Pressure The upper limit of drawdown pressure that can be applied to a completion system without causing damage to the system (such as erosion to a gravel pack completion system). Critical_Gas_Saturation Critical_Saturation The value of gas saturation at which gas will begin to flow, as gas saturation is increased. Critical_Oil_Saturation Critical_Saturation The value of oil saturation at which oil will begin to flow, as oil saturation is increased. Critical_Pressure Pressure The pressure needed to condense a vapor at its critical temperature. Applies to pure components; for mixtures use Pseudocritical_Pressure. Critical_Saturation Saturation The value of saturation of a specific fluid phase at which the fluid will first begin to flow as saturation is increased. Critical_Temperature Temperature The highest temperature at which a fluid can exist as a liquid and above which its vapor cannot be liquefied regardless of the amount of pressure. Applies to pure components; for mixtures use Pseudocritical_Temperature. Critical_Volume Data_Valued_Property The inverse of density at the critical point of a fluid, describing the volume occupied by a fluid of unit mass. Critical_Water_Saturation Critical_Saturation The highest water saturation a hydrocarbon-producing rock can maintain before water will begin to flow. Cross_Section_Area Surface_Area The cross-sectional area of a solid object; e.g., area of perforation in a cased borehole. Crossflow_Coefficient Coefficient Characterization of the flow in the reservoir from one layer to another layer, usually known as "Omega" in Reservoir Dynamics Crossflow_Flag Flag Indicates presence of crossflow Crossline_Dip Dip_Angle Angle that a surface, e.g. a bedding or fault surface, makes with the horizontal, measured in the cross-line direction. Crossplot_Porosity Apparent_Porosity Estimate of porosity determined by plotting one type of data against another. Crushed_Zone_Permeability Permeability Permeability of the Crushed Zone around perforation Crushed_Zone_Thickness Thickness Thickness of the Crushed Zone around perforation Cultural_Feature_Type Type The type of cultural feature that is to be found on a map Cumulative_Borehole_Volume Borehole_Volume Cumulative volume of the borehole (integrated over length of borehole). Cumulative_Cement_Volume Cement_Volume Cumulative volume of cement (may be integrated over length of borehole or over time of cementing operation). Cumulative_Condensate_Volume Cumulative_Production_Volume Cumulative condensate production. Cumulative_Equivalent_Time Time_Interval Cumulative Equivalent Operating Time, called Cumulative Time Usage or CTU. Cumulative_Gas_Volume Cumulative_Production_Volume Cumulative gas production at standard conditions. At constant BHP or WHP, cumulative volume is not the straightforward sum of volume by RHU but determined by Inverse Laplace transformation. Cumulative_Oil_Volume Cumulative_Production_Volume Cumulative oil production at standard conditions. At constant BHP or WHP, cumulative volume is not the straightforward sum of volume by RHU but determined by Inverse Laplace transformation. Cumulative_Production_Volume Volume Volume of fluids produced by a zone or interval since the beginning of the production Cumulative_Volume Volume The cumulative volume, typically of a fluid. Cumulative_Water_Influx Volume The cumulative volume of water that encroaches into a reservoir. Cumulative_Water_Volume Cumulative_Production_Volume Cumulative water production at standard conditions. Currency_Code Code Money currency (US$, French franc..) Current_Density Data_Valued_Property Current per unit cross-sectional area. Current_Equivalent_Time Time_Interval Computed equivalent operating time based on the time spent at a given temperature and the maximum working temperature. If all the time is spent at maximum working temperature, then the equivalent time is equal to the operating time. Curvature Shape A measure of the degree to which a path is curved relative to the length of the path along the curve. Curvature_Radius Radius Radius of the circle whose arc would have a given curvature. Cushion_Type Type Type of fluid in the test string prior to initial open of the well. Cutter_Count Count Number of cutters, as for drilling hole openers and reamers. Cutter_Set_Weight Weight Approximate weight of the set of cutters Cutter_Type Type Type of cutters, as used in drilling reamers (such as Type T, F, or B) Cuttings_Diameter Diameter Average diameter of drill cuttings. Cycle_Sample_Count Count Target number of samples per hour. Cyclic_Redundancy_Check Quality_Indicator CRC test value for this Calibration Coefficient set. Cylindrical_Position Location Set of coordinates specifying the position of a point in a cylindrical coordinate system DST_Gauge_Adapter_Code Code Code for the DST Gauge Adapter DST_Gauge_Type Type Type of DST Gauge Adapter Daily_Prognosis Description Description of activities and events anticipated during the next 24 hours. Damaged_Zone_Mobility Mobility Mobility of the near-wellbore Damaged Zone, the sandface layer around the wellbore where permeability and mobility are impaired, generally by a damaging material (e.g. completion or drill mud). Damaged_Zone_Permeability Permeability Permeability of the near-wellbore Damaged Zone, the sandface layer around the wellbore where permeability and mobility are impaired, generally by a damaging material (e.g. completion or drill mud). Damaged_Zone_Thickness Thickness Thickness of the near-wellbore Damaged Zone, the sandface layer around the wellbore where permeability and mobility are impaired, generally by a damaging material (e.g. completion or drill mud). Data_Acquisition_Mode Indicator Software or hardware option whose selection controls some aspect of data acquisition. Data_Compression_Flag Flag Flag indicating whether or not downhole data compression is possible with this equipment. Data_Direction Type Direction of data flow, e.g. Input, Output or both. Data_Focus_Type Type Indicates how the entity set to be used as the starting point of a query is formed. Data_Mask Data_Valued_Property Data pattern which allows storage and access of several types of independent data within a simple representation; common masks use individual bits of integer representations, or individual characters of string representations, to carry independent information. Data_Presence_Flag Flag An indicator which shows that some particular type of data is available. Data_Reduction_Type Type Method used for data reduction, e.g. Linear decimation, Logarithmic, etc. Data_Valued_Property Property A property whose value contains data. Date Absolute_Time The date, usually expressed in the format of the DBMS; e.g., Oracle date format is dd-mm-yy. Date_Format Format Specification of how date information will be formatted. Dead_Volume Volume Volume of material remaining in a container after normal emptying procedure, and thus not available for use. Dead_Weight Mass Weight of material unavailable for use remaining in a container Decimation_Factor Coefficient Number indicating the degree of data reduction from decimation (resampling at lower sampling frequency); e.g. a Decimation_Factor of 5 indicates that only every 5th input sample is retained as output. Declination Plane_Angle The angle between the celestial equator and a celestial body, measured along a great circle passing through the celestial poles. Deep_Conductivity Conductivity The conductivity which represents a measurement made several feet into the formation; generally considered a measurement of the undisturbed formation. Deep_Induction_Conductivity Deep_Conductivity The conductivity, measured by an induction log, which represents a measurement made several feet into the formation; generally considered a measurement of the undisturbed formation. Deep_Induction_Resistivity Deep_Resistivity The resistivity, measured by an induction log, which represents a measurement made several feet into the formation; generally considered a measurement of the undisturbed formation. Deep_Lateral_Resistivity Deep_Resistivity Resistivity measurement using a "lateral" electrode arrangement with a "deep" investigation radius (several feet into the formation). Deep_Laterolog_Conductivity Deep_Conductivity The conductivity, measured by a laterolog (or guard log) resistivity device, which represents a measurement made several feet into the formation; generally considered a measurement of the undisturbed formation. Deep_Laterolog_Resistivity Deep_Resistivity The resistivity, measured by a laterolog (or guard log) resistivity device, which represents a measurement made several feet into the formation; generally considered a measurement of the undisturbed formation. Deep_Resistivity Resistivity The resistivity which represents a measurement made several feet into the formation; generally considered a measurement of the undisturbed formation. Def_Currency Name Default Currency used Def_Display_Type Type Default type of display used for a data object, such as an Array. Def_Language Language Default Language used Def_Unit Unit_Code Code of default Unit Def_Unit_System Unit_System_Code Default Unit System used Def_Value_Number Multi_Use_Property Default value if number Def_Value_String Multi_Use_Property Default value if string Definition Description A full textual description of the meaning of a term. Degradation_Factor Quality_Indicator Indication of the extent to which the quality of an object or of data has been degraded. Degree_Of_Confidence Quality_Indicator The degree of confidence associated with any event or feature related to or detected, for example a geologic feature in/on the Earth (high, low, etc) Delay_Time Time_Interval The time difference by which one event lags another. In refraction seismic work, the additional time required to traverse a raypath over the time which would be required to traverse the horizontal component at the highest velocity encountered on the raypath. Density Data_Valued_Property The density (mass per unit volume) of a material. Usually at Standard conditions (STP). Also used to indicate the frequency of occurrence. Density_Caliper Caliper Borehole diameter as estimated by a density logging device. Density_Data_Density MWD_Data_Density Density of data samples per length of borehole traversed, for a bulk density logging measurement. Density_Gradient Gradient A measure of the change in the density of a material per unit length. Density_In Density Density of the input material, such as the drilling fluid in the mixing tank. Density_Out Density Density of the output fluid, such as the drilling fluid returning from the well annulus. Density_Porosity Apparent_Porosity Porosity derived from a formation density measurement. Density_Porosity_Dolomite Density_Porosity Porosity derived from a formation density measurement, assuming that the rock matrix material is dolomite. Density_Porosity_Limestone Density_Porosity Porosity derived from a formation density measurement, assuming that the rock matrix material is calcite. Density_Porosity_Sandstone Density_Porosity Porosity derived from a formation density measurement, assuming that the rock matrix material is quartz. Density_Quality_Indicator Quality_Indicator Property used to indicate quality or confidence of data from a density logging survey. Density_Time_After_Bit Time_After_Bit In MWD/LWD logging, the time delay between the drill bit and a density sensor reaching a given point in the wellbore. Depositional_Environment_Type Type The type of deposition that has created a particular Earth environment, e.g. Reef, Beachrock, Pointbar, etc. Depth Length The perpendicular measurement downward from a surface. Also, the direct linear measurement from the point of viewing usually from front to back. Depth_Dip Dip_Angle Dip computed on a depth surface by measuring the difference in depths between two points compared to the horizontal distance between the points. Depth_Increment Interval_Length Length of interval which is used as a regular increment to depth-based processing. Depth_Offset Length Offset in depth versus some depth reference. Depth_Unit Unit_Code Unit for depth data Depth_Value_Type Value_Type_Code Value type of depth data Derivative_Model Type Derivative Model used in evaluating this Transient, e.g., Backward, Central, or Forward. Derivative_Type Type Type of derivative used in evaluating this transient. Derived Modifier The data related to the property is an output of empirical equations or other equations based on input data from multiple sources. Derived_Inverse_Flattening Flag Flag indicating that the inverse flattening value of an ellipsoid has been derived from semi-major and semi-minor axis lengths. Derived_Minor_Axis Flag Flag indicating that the semi-minor axis value of an ellipsoid has been derived from the semi-major axis length and a flattening value. Description Data_Valued_Property The description or complete definition of any data item or object Detection_Gain Coefficient Coefficient used to adjust signal amplitude for detection of some event, such as the first arrival in a sonic waveform. Deviation Plane_Angle Angular departure from some reference direction. When used with wells, it is the angle between the borehole axis and the vertical (also known as the Drift Angle). Deviation_Skin Skin_Factor The skin effect caused by the well trajectory not being perpendicular to the bedding plane. Dew_Point_Pressure Pressure The pressure at which a liquid phase condenses from a vaporous fluid in equilibrium at a given temperature. Diameter Length Length from one side of an object to the other measured along a straight line through the center of the object Diameter_Restriction Description Description of the change in diameter within a well or a borehole. Diameter_Unit Unit_Code Unit for diameter data. Dielectric_Constant Permittivity The ratio of the Permittivity of a material to that of free space. Dielectric_Resistivity Resistivity Resistivity measurement which has been compensated for the dielectric constant of the formation.. Diff_Pressure_Gauge_Type Type Sensor used to acquire gas differential pressure across orifice plate Differential_Caliper Diameter The difference between the actual borehole diameter and bit size. Differential_Pressure Pressure The difference between the pressures of two systems, or between the pressures measured at different points in a system. Differential_Speed Angular_Velocity The differential speed between the bowl and the conveyor of a centrifuge. Differential_Temperature Temperature The difference in temperature between two objects or materials. Diffusivity Data_Valued_Property A measure of the tendency for diffusion to occur. See Hydraulic_Diffusivity. Digital_Encoding Format Identification of how data are encoded digitally; e.g. ASCII, Binary, etc. Digital_File_Format Format The type of file structure in which the depiction rendering is encoded; e.g. PostScript, ANSI text, GIFF, JPG, Maker Interchange Format (MIF), SGML, HTML. Digital_File_Format_Version Version Identification of the digital file format version (e.g., 3.0a). Note that this information is often encoded within the file. Dilation_Angle Plane_Angle Angle relating the increase in volumetric strain with stress. Dimension_Count Count The number of dimensions for an object or a representation of such an object, e.g. dimensions of an array. Dimensionless_Borehole_Radius Borehole_Radius Dimensionless Borehole Radius ("rwD") Dimensionless_Boundary_Distance Well_To_Boundary_Distance Distance to a boundary divided by wellbore radius Dimensionless_Changing_Storage_Pressure Pressure Dimensionless changing wellbore storage pressure ("CphiD") Dimensionless_Fracture_Conductivity Fracture_Conductivity Ratio of fracture conductivity (fracture permeability x average width) to the (matrix permeability x fracture half_length) product. Standard industry acronym : "FCD", S.P.E. preferred form "CfD". Dimensionless_Interwell_Distance Interwell_Distance Dimensionless inter-well distance for a horizontal interference test Dimensionless_Layer_Diffusivity Layer_Diffusivity Ratio of layer storativity ratio to layer transmissibility ratio ("etaDj") Dimensionless_Rectangle_Length Rectangle_Length Rectangle length divided by reference length ("BxD") Dimensionless_Rectangle_Width Rectangle_Width Rectangle width divided by reference length ("ByD") Dimensionless_Well_X_Position X_Coordinate Well position expressed as fraction of rectangle length ("xbx") Dimensionless_Well_Y_Position Y_Coordinate Well position expressed as fraction of rectangle width ("yby") Dip_Angle Plane_Angle The maximum vertical angle that a surface; e.g. a bedding or fault surface, makes with the horizontal, measured perpendicular to the strike direction of the structure. Dip may be computed in several ways, including from logs, from well-to-well correlation, from gradients on interpreted time or depth surfaces (See Time_Dip and Depth_Dip), etc. Dip_Azimuth Azimuth Azimuth of the direction of maximum dip of a surface; dip may be computed in several ways, including from logs, from well-to-well correlation, from gradients on interpreted time or depth surfaces, etc. Dip_Detection_Source Source The source of information used to detect dips (e.g., Seismic data, Structural analysis, Dipmeter log data, etc.) Dip_Height Height Height of Dip Plane Intersection with Borehole Dip_Number Ordinal_Number An ordinal identifier that characterizes uniquely each dip Dip_Pattern_Shape Shape Shape of a dip pattern, e.g. Convex, Concave, etc. Dip_Pattern_Type Type The type of pattern created by the earth dipping planes, e.g. Green, Red, Blue, etc. Dip_Quality Quality_Indicator Induced quality of the dip value based on evaluation of the quality of the measured data. Ranges from 0 (bad) to 20 (good) Dip_Quality_Cutoff Quality_Indicator The lowest dip quality taken into account for an interpretation. Dip_Type Type The type of dipping associated with subsurface planes; e.g., CrossBedding, Fault, Fracture, BedBoundary, etc. Dip_Valid_Zone_Type Type This property specifies whether the zone where the dips were computed corresponded to a Blank zone with no dips, a Mirror Image zone, or a borehole Washout zone. Direction Orientation The line or course on which something is moving or is aimed to move or along which something is pointing or facing. Direction_Channel_To_Axis Azimuth Azimuth of the direction to an axis, usually pertaining to a sedimentary channel. Direction_Channel_To_Flow Azimuth Azimuth of the direction to flow, usually pertaining to a sedimentary channel. Direction_Channel_To_Land Azimuth Azimuth of the direction to land, usually pertaining to a sedimentary channel. Direction_Current Azimuth The azimuth of the flow direction that insured transportation an deposition of the sediments. Direction_Downthrown_Block Azimuth Azimuth of the direction to the downthrown block in case of faulting in the Earth subsurface. Direction_Overthrust Azimuth Azimuth of the direction of overthrust in case of faulting in the Earth subsurface. Direction_To_Source Azimuth The direction from which sediments are brought Directional_Permeability Permeability An oriented permeability within a porous media, expressed either as horizontal (along the bedding plane of the stratum) or vertical (perpendicular to the bedding plane of the stratum), or within a coordinate system. Disclaimer Data_Valued_Property Legal text on the front page describing the legal status of this document as regard of liability. Discontinuity_Type Type The type of discontinuity: a detectable interruption in the material which may or may not have undesirable connotations (e.g. crack, lap, seam, pit, lamination, etc.) Discriminator_1_Cutoff Threshold Cutoff value for first discriminator Discriminator_2_Cutoff Threshold Cutoff value for second discriminator Displaced_Fluid_Type Fluid_Type Type of fluid displaced by the injection of another fluid. Displacement Length The linear distance which a point or object is displaced with respect to another, usually as the result of some activity or process. Displacement_Efficiency Efficiency The fraction of displaceable fluids/hydrocarbons that has been actually displaced when contacted by a displacing fluid. Displacement_Velocity Velocity The velocity of the shock or displacement front. Displacing_Fluid_Volume Volume Volume of fluid used to displace another fluid. In special core analysis, may be expressed as unitless multiple of pore volume. Display_Index_Type Axis_Index_Code Type of index used for display; e.g. MD, DSRD, TVD etc. Display_Name Name A name which is used for display purposes, as opposed to the formal controlled name (Code) which is used for interoperability. Display_Name_Format Format Specification of how the name of a data item will be displayed to the user. Distance Length Amount of separation between two points, lines, surfaces, or objects measured along the shortest path joining them. Distance_Unit Unit_Code Unit for distance data, typically m or ft. Documentation_File File_Name Name of file containing related documentation Dolomite_Volume_Fraction Volume_Fraction The volume fraction of dolomite with respect to the total volume. Dominant_Frequency Frequency Predominant frequency within power spectrum. Dominant_Wavenumber Wavenumber Dominant Wavenumber in depth domain. Reciprocal of distance between successive peaks or troughs. Dosing_Mode Type The way an additive is measured e.g. By Weight Of Cement, BOW, gl/sk .... Dowell_Chemical_Code Code Reference to the Dowell chemical product catalog Down_Load Load Downward load exerted on an equipment item. Down_Stroke Stroke_Length Down stroke distance, as used for drilling jars. Downhole_Cable_Tension Tension Tension of the logging cable as measured at the top of the logging tool Downhole_Inclination Hole_Deviation Inclination of the drillstring as measured downhole Downhole_Torque Torque Downhole torque, as applied to the drill string Downstream_Coil_Pressure Pressure Coil working pressure downstream of the choke box Downstream_Orifice_Gas_Pressure Pressure Pressure of gas separator gas line downstream of orifice plate when a sample is taken Downtime Time_Interval Time during which equipment is not operational condition or is otherwise unavailable. Downtime_Ratio Ratio Non-operational time of an equipment with respect to total time in location Drag Force In drilling, the extra force needed to move the drillstem resulting from the drillstem being in contact with the borehole wall. Drainage_Area Surface_Area The drainage area of a reservoir. Drainage_Area_Shape_Factor Indicator The shape factor for enclosed drainage areas, used to correct pseudosteady-state flow performance behavior of sinks in non-circular drainage regions. Drawdown_Pressure Bottomhole_Pressure The difference in shut in and flowing bottomhole pressures, at a constant rate of fluid production. Drift_Diameter Inside_Diameter Largest diameter of a perfect cylinder of a specified length that can fit into the pipe. Because a pipe is never perfectly cylindrical but slightly oval the drift diameter is always smaller than the quoted inner diameter. The drift diameter is used to know if a given pipe or instrument will run into a pipe. Drift_Gradient Gradient The change in the borehole drift per length, usually referring to the borehole measured depth. Drift_Time Time_Interval The difference between actual acoustic travel time to a subsurface point (as measured in a check shot survey) and the integrated acoustic slowness from sonic logging data. Drill_Bit_Code Code Specific drill bit code given by the manufacturer and usually approved by the IADC. Drill_Bit_Grade_IADC Grade The IADC, the International Association of Drilling Contractors, grading of a drill bit based on certain criteria; e.g., Bearing Seals, Dull Characteristic, Gauge, etc. grading. Drill_Bit_Grade_TBG Grade The TBG, Teeth-Bearing-Gauge, grading assigned to a drill bit based on particular criteria. The TBG has 5 fields: Bearing, Broken Teeth, Gauge, Gauge Out of Hole, Tooth Wear. Drill_Bit_Grade_Wear Grade Drill Bit wear grading in percentage. Drill_Bit_Type Type Generic type of the drill bit, such as Roller Cone or PDC. Drill_Collar_Type Type Generic type of drill collar, such as spiral, normal, slip & elevator Drill_Downhole_Tool_Code Code Specific code of the downhole drilling tool. Drill_Downhole_Tool_Type Type Generic type of downhole drilling tool. Drill_Fluid_Code Code Specific code of the drill fluid. Drill_Fluid_Name Name Name given to the drill fluid Drill_Fluid_Type Fluid_Type Generic type of the fluid used during a drilling activity; e.g., chemical gel mud, crude oil, caustic (high ph), gypsum mud, native mud, air, salt water, etc. Drill_Fluid_Volume Volume Volume of drilling fluid Drill_Hole_Opener_Reamer_Code Code Specific code of the hole opener or reamer. Drill_Hole_Opener_Reamer_Type Type Generic type of tool i.e. standard, bull nose hole opener, underreamer, LHO (Large Hole Opener with rollers),roller reamer, 3-Point Roller Reamer, 6-Point Roller Reamer Drill_Jar_Shock_Code Code Specific code of the drill jar or shock sub. Drill_Jar_Shock_Type Type Generic type such as hydraulic jar, mechanical jar, shock sub Drill_Motor_Code Code Specific code of the Motor or Turbine. Drill_Motor_Type Type Generic type of the Motor or Turbine used during a drilling activity. Drill_Operation_Mask Data_Mask Mask for the drilling operating mode, such as 0001 - Rotating, 0010 - Sliding, 0100 - Reaming, 1000 - Trip in, 10000 - Trip out Drill_Pipe_Grade Grade Drill pipe grade Drill_Pipe_Type Type Generic drill pipe type such as Normal Grade, Heavy Weight, Hevi-Wate, or Thick Wall Drill_Slot_Cluster_Type Type Generic type of drill slot cluster such as template and pad Drill_Stabilizer_Code Code Specific code of the drill stabilizer. Drill_Stabilizer_Type Type Generic stabilizer type such as Welded Blade, Integral Blade, Replaceable Sleeve, Clamp-on, Rubber Sleeve, Rockback, RWP (replaceable wear pad) Drill_Structure_Code Code Code which uniquely identifies a particular drill structure Drill_Structure_Name Name Name of the Rig or Drill Structure operating on the well Drill_Structure_Type Type Generic type of drilling structure such as land rig, barge rig, submersible rig, jack-up rig, semisubmersible rig, drillships, structure rig Drill_Sub_Type Type Type of sub - bent, bent orienting, cross-over, bitsaver, kelly-saver, extension, UBHO (Universal Bottom Hole Orienting), float, saver, lift, pressure release, etc Drill_Survey_Tool_Code Code Specific code of survey tool. Drill_Survey_Tool_Type Tool_Type Generic type of survey tool such as single shot, multi shot, gyro. Driller_Elevation_Reference_Code Code Code of the elevation reference for drilling data Driller_Total_Depth Total_Depth The total depth of the well borehole as reported by the drilling contractor. Drilling_Time Operating_Time Elapsed time during which drilling has taken place. Drillstring_Drive_Torque Torque Torque applied to the drillstring, measured at the rotary table or top-drive. Dry_Clay_Volume_Fraction Volume_Fraction The volume fraction of dry clay with respect to the total volume. Dry_Gas_Critical_Pressure Critical_Pressure The pressure needed to condense a dry gas at its critical temperature (Dry gas = free gas without condensate) Dry_Gas_Critical_Temperature Critical_Temperature The highest temperature at which a gas can exist as a liquid and above which its vapor cannot be liquefied regardless of the amount of pressure (Dry gas = free gas without condensate) Dry_Gas_Gravity Gas_Gravity The ratio of the molecular weight of the dry gas to that of air (Dry gas = free gas without condensate) Dry_Weight_Fraction Ratio The ratio of the dry weight of a component of a system to the total dry weight of the system. Dune_Shape Shape Shape of a Dune type depositional environment, e.g. Dome, Parabolic, etc. Duration Time_Interval Elapsed time from the start to the finish of a process or activity. Duration_Unit Unit_Code Unit for this Data Duty_Cycle Data_Valued_Property Amount of time it takes to start, operate, stop and idle a machine when it is used for intermittent duty; also, proportion of working time as compared to total operating time. EOU_Computation_Method Method_Type Method used for calculating the ellipse of uncertainty: 0 - Wolfe & de Wardt; 1 - Conic EOU_Cone_Depth_Increment Depth_Increment Depth increment of the ellipse of uncertainty cone EOU_Cone_Growth_Ratio Ratio Ratio of the ellipse of uncertainty cone radius increase per depth increment EOU_Cone_Surface_Radius Radius The radius of the ellipse of uncertainty cone at the surface location East_Departure X_Coordinate Displacement to the East relative to some coordinate system origin; e.g., the east component of the well departure from the vertical. (Negative value is departure to the West.) East_West_Distance X_Coordinate East or West distance from the boundary line indicated by East_West_Line to the survey point. East_West_Line Type Indicates whether the East or West boundary line of the survey area has been used as a reference for East_West_Distance values. Eastern_Meridian Longitude The meridian on a graticule that is the eastern extreme on a map projection. Eccentering Length A measure of the amount by which an object is off-center with respect to another; e.g. the displacement between the axis of a logging tool and the borehole axis. Eccentering_Azimuth Azimuth Azimuth of the line from the center of an area to an eccentered object. Eccentering_Azimuth_Offset Plane_Angle Offset in azimuth due to eccentering; used to convert azimuth values with respect to an eccentered position into azimuth values relative to center. Eccentricity Shape The ratio of the focus-to-center distance to the length of the semi-major axis of an ellipse. Eccentricity_Squared Shape The square of the ratio of the focus-to-center distance to the length of the semi-major axis of an ellipse. Echo_Amplitude Amplitude The amplitude of an echo signal. Eff_Formation_Stress Stress Effective Stress of completed interval Eff_Inside_Diameter Inside_Diameter Effective inside diameter for stiffness, as used for drilling tools. Eff_Reservoir_Radius Reservoir_Distance The characteristic radius of a reservoir used to quantify the behavior of a reservoir. This is the radius that a reservoir would have if circular in shape. Effective_Date Date The date on which a contract becomes effective or put in force. Effective_Length_Thickness_Ratio Ratio A measure of the tendency of a permeable stratum to exhibit vertical equilibrium of flowing fluids, defined as: (length / height) * SQRT(kv/kh), where length is the characteristic length of the flow path and height is the gross or net height. Effective_Permeability Permeability The measure of the capacity of a single fluid to flow through a rock when the pore spaces of the rock are not completely filled or saturated with the fluid. Effective_Permeability_Gas Effective_Permeability The measure of the capacity of gas to flow through a rock when the pore spaces of the rock contain other fluids. Effective_Permeability_Gas_Sor Effective_Permeability_Gas Effective permeability to gas at residual oil saturation. Effective_Permeability_Gas_Swi Effective_Permeability_Gas Effective permeability to gas at initial water saturation. Effective_Permeability_Gas_Swr Effective_Permeability_Gas Effective permeability to gas at residual water saturation. Effective_Permeability_Oil Effective_Permeability The measure of the capacity of oil to flow through a rock when the pore spaces of the rock contain other fluids. Effective_Permeability_Oil_Swi Effective_Permeability_Oil Effective permeability to oil at initial water saturation. Effective_Permeability_Water Effective_Permeability The measure of the capacity of water to flow through a rock when the pore spaces of the rock contain other fluids. Effective_Permeability_Water_Sor Effective_Permeability_Water Effective permeability to water at residual oil saturation. Effective_Porosity Porosity The porosity available to free fluids, excluding non-connected porosity and space occupied by bound water. Efficiency Data_Valued_Property The ratio of the useful energy delivered by a dynamic system to the energy supplied to it. Elastic_Impedance Acoustic_Impedance Property which controls the propagation of a seismic wave at a particular (non-zero) angle of incidence. It is a function of the material density, the compressional wave velocity within the material, the ratio between the shear and the compressional wave velocities, and the angle of incidence. This property, analogous to Acoustic_Impedance but for non-zero incidence angles, is described in 1998 SEG Paper "Calibration and Inversion of Non-Zero Offset Seismic Data", by Patrick Connolly (BP). Elastic_Limit Pressure The greatest stress that can be applied to a body without causing permanent deformation. Elastic_Modulus Pressure The stress-strain properties of isotropic materials which obeys Hooke's law, for small formations, are specified by elastic moduli. Electric_Charge Data_Valued_Property A definite quantity of electricity. Electric_Current Data_Valued_Property Flow of electric charge within an electromagnetic field, per unit time. Electric_Field_Strength Gradient The force per unit charge (or voltage gradient). Electric_Potential Data_Valued_Property A measure of Voltage Electric_Potential_Gradient Gradient Electric potential difference per unit of length. Electric_Susceptibility Data_Valued_Property Ratio of electric field strength to electric polarization. Electrical_Penetration Borehole_Diameter The apparent borehole diameter as viewed by electrical measurements Electrical_Property Data_Valued_Property Coarse classification of the electrical nature of a material; e.g. Conductive, Resistive Electrical_Stability Data_Valued_Property Measure of the emulsion stability and oil-wetting capability in oil based drilling fluids. Electrochemical_Equivalent Data_Valued_Property The mass in grams of a substance produced or consumed by electrolysis (with 100% current efficiency) during the flow of a quantity of electricity equal to 1 Faraday (96,487 Coulombs); conventional unit is the "equivalent" (eq). Electrochemical_Potential Electric_Potential The component of the Spontaneous or Self Potential comprised of the sum of the liquid-junction and the shale-membrane potentials, both of which are related to ratio of the activity of the formation water to that of the mud filtrate. Electrokinetic_Potential Electric_Potential A voltage which results from the flow of a fluid containing ions. A component of the Spontaneous or Self Potential. Electromagnetic_Attenuation_Rate Attenuation_Rate A measure of the rate of attenuation of an electromagnetic wave per unit length. Electromagnetic_Caliper Caliper Borehole diameter as estimated by an electromagnetic logging device. Electromagnetic_Phase_Shift Phase_Shift Difference in phase of two electromagnetic waves. Electromagnetic_Power Power The rate at which electromagnetic energy is emitted or transferred. Electromagnetic_Propagation_Resistivity Resistivity Formation resistivity as measured by the attenuation or phase shift of a high frequency electromagnetic wave; the frequency range for these measurements is higher than that of induction measurements, typically hundreds of KHz to several MHz, and over 1 GHz in the case of the Schlumberger EPT tool. Electromagnetic_Propagation_Time Interval_Transit_Time Time per unit length required for an electromagnetic wave to propagate over some interval in some medium like air, water, drilling fluid, etc.. Electron_Density Bulk_Density Electron density. Gamma-gamma logging techniques respond to electron density, which is near bulk density for most formation types. Element_Code Code Code of the Element type that participates in this collection. If NULL, any type is allowed in the collection. Element_Count Count The number of elements, usually in an array or along an axis. Element_Table Table_Name Table containing an element of a collection. Element_Tag Name Tag (label) used to reference an Element of a Collection. Elemental_Yield Data_Valued_Property The fractional contribution of an element to the total; in induced gamma-ray spectroscopy, it is the fraction of the counts in the measured spectrum due to a given element. Elevation Height Height of some point above a horizontal reference plane. Elevation_CDP Elevation Surface elevation at a CDP with respect to mean sea level. Elevation_Reference_Code Code Code of the local elevation reference, such as "KB" for "Kelly Bushing". Elevation_Reference_Name Name Name of the local elevation reference, such as "Kelly Bushing". Ellipsoid_Code Code Code of the ellipsoid to which geodetic coordinates are referenced. Ellipsoid_Name Name Name of the ellipsoid to which geodetic coordinates are referenced. Ellipticity Shape The ratio of the major to minor axes of an ellipse. Email_Address Address Address used for electronic mail, such as an Internet address (clinton@white_house.gov) End_Age Geologic_Age The latest (numerically smallest) geologic or geochronologic age associated with an event or item, such as an earth layer, a fossil or pollen type. End_Age_Code Geologic_Age_Code The code of the latest (most recent) geologic or geochronologic age associated with an event or item, such as an earth layer, a fossil or pollen type. End_Date Date The date/time of the end of an activity. End_Time Absolute_Time Time at which a process ended Energy Data_Valued_Property Capacity for doing work Energy_Half_Depth Energy_Half_Z Depth, within a specified interval, at which half the energy of the interval occurs Energy_Half_Time Energy_Half_Z Time, within a specified interval, at which half the energy of the interval occurs Energy_Half_Z Ratio Characterization of relative distribution of energy in a layer, computed as the fractional displacement (depth or time) into an interval (layer, bed) where half of the energy is above, half below. Engine_Oil_Pressure Pressure Pressure of the lubrication oil Engine_Oil_Temperature Temperature Engine lubrication Oil Temperature Engine_Total_Time Operating_Time Time spent by an engine in operating condition since the last overhaul. Enhanced Modifier Made greater (as in value). Enthalpy Energy The internal energy of a thermodynamic system plus the product of its pressure and volume. Entity_Code Code Code of SDM Entity Entity_Object Object_Name Name of the implementation object of the entity. A table name in a relational implementation. Epithermal_Neutron_Near_Far_Ratio Ratio Ratio of the count rate of the near detector to that of the far detector in an epithermal neutron logging device Epithermal_Neutron_Porosity Neutron_Porosity Porosity as measured with an epithermal neutron device. Equilibration_Ratio Ratio The equilibrium vaporization ratio, or ratio of the mole fraction of a fluid system component in the vapor phase divided by the mole fraction of the same component in the liquid phase. Equipment_Test_Pressure Pressure Recommended pressure the equipment is tested when inspected or certified Equipment_Type Type The type or class of an equipment used for some activity, e.g. Sensor, Drill Bit, Turbine, etc. Erosion_State Status Describes if the event has been partially, totally, etc. subjected to erosion. Error Statistical_Property The deviation of a measurement from the true value; usually expressed as an absolute quantity rather than as a fraction; the unit quantity is determined by that of the data. Error_Band Statistical_Property Tolerance range within which the measurement should remain; the sum of the positive and negative tolerances. May be scaled in measurement units or expressed as a proportion of the instrument rating. Estimated Modifier Obtained using a rough or approximate calculation, such as a numerical value obtained from a statistical sample and assigned to a population parameter. Estimated_Borehole_Volume Borehole_Volume The estimated volume of the Open Hole used in fluid volume/placement computations Estimation_Flag Flag Indicates whether the data are an estimation (Y) or not (N) Etched_Half_Length Length Half Length of formation etched (dissolved) by reaction with acid (Acid fracturing) Etched_Width Width Width of formation etched (dissolved) by reaction with acid on the fracture face (Acid fracturing) Evaporite_Volume_Fraction Volume_Fraction The volume fraction of evaporitic rock with respect to the total volume. Event_Class Type Event classification by type Event_Date Date The date of an event. Event_Location Location Describes where the event took place, e.g., Well Head, Separator Event_Subclass Type Event classification by Subclass Event_Time Time_Interval Time of an event, such as a pick time from a waveform, expressed as the elapsed time from a chosen "zero" time. Event_Time_0 Event_Time Event Time 0 Event_Time_1 Event_Time Event Time 1 Event_Time_2 Event_Time Event Time 2 Event_Time_3 Event_Time Event Time 3 Event_Time_4 Event_Time Event Time 4 Execution_Date Date The date that a contract is executed, usually the date of signing of the last signatory Existence_Kind Type Classification of the lifecycle state of an entity: actual, planned, predicted, etc. Expansion_Factor Indicator A factor that accounts for the change in gas density due to pressure changes, as across an orifice. Expected_Life Operating_Time Expected operating time of the equipment, generally defined as operating time of the first failure for 95% of the equipment Expiration_Date Date Expiration date of a legal document or an item. Expiry_Date Date The date at which a contract terminates or is no longer in force. If the expiry date is amended, this is the amended date. Explicit_Index Multi_Use_Property Token, normally an integer, which is used as a reference or pointer to a value stored in some data structure. Exponent Data_Valued_Property A number, normally symbolized as a superscript to a term in an expression, which indicates the power to which the term is raised. Exposure_Class Code Classification of the installation location and resulting environmental risk, i.e., liquid, dust, shock,... External_Boundary_Pressure Pressure The pressure existing at the external boundary of the drainage area of the well. External_Drainage_Radius Reservoir_Distance The characteristic radius to the outer drainage boundary of a field or a reservoir Extrapolated_Pressure Pressure Extrapolated pressure from infinite-acting analysis Extrapolated_Pressure_Sph Extrapolated_Pressure Extrapolated pressure from spherical flow analysis FIT_Equivalent_Mud_Weight Mud_Density Equivalent mud weight determined by the formation integrity test (FIT) for a new formation below last casing shoe via increasing the pressure until a pre-determined value. Facies_Boundary_Type Type The type of a Facies Boundary in the Earth subsurface Facies_Type Type The type of a Facies in the Earth subsurface Fan_Shape Shape Shape of a Fan type depositional environment, i.e. Elongated or Crescent. Fann_Test_Pressure Pressure The pressure at which the Fann test was performed. Fann_Test_Temperature Temperature The temperature at which the Fann test was performed. Fault_Character Type The characterization of a Fault in the Earth subsurface, e.g. Sealing, Non Sealing, Constant Pressure, etc. Fault_Control_Flag Flag Flag marking if a layer is affected by faulting. Fault_Detection_Source Source The source of the data used to detect faults (e.g., Seismic data, Structural analysis, Dipmeter log data, etc.) Fault_Displacement Displacement The measure of the relative movement of the 2 sides of a fault. Fault_Distortion_Type Type The type of distortion associated with a fault plane, e.g. Rollover, Drag, etc. Fault_Hade Plane_Angle The angle that a fault plane makes with the vertical. Fault_Heave Displacement Horizontal component of separation or displacement on a fault. Fault_Strike Azimuth The azimuth of the strike of a fault. Fault_Throw Height Length of the vertical displacement of a Fault. Fault_Transmissibility Ratio Ratio of fault transmissibility to formation transmissibility. Fault_Type Type The type of a Fault in the Earth subsurface, e.g. Normal, Hinge, Reverse, Dextral, etc. Faulting_Time_Wrt_Sedimentation Type Time of faulting with respect to the sedimentation process, e.g. Post Deposition, Post Compaction, etc. Faulting_Time_Wrt_Tilt Type Time of faulting with respect to tectonic events which tilted the bed, e.g. Anterior, Posterior Fax_Number Phone_Number Telephone number used for FAX (facsimile) transmission and/or reception. Feature_Dip Dip_Angle Dip computed on a general feature surface by measuring the difference in attribute values between two points compared to the horizontal distance between the points. Feature_Intersection_Type Type Defines how a Wellbore intersects with a Geologic Feature Feldspar_Volume_Fraction Volume_Fraction The volume fraction of feldspar with respect to the total volume. Field_Name Name Name given to a field; may be a company-specific or regulatory name. File_Name Name The name of a computer data file. File_System_Name Name Name of computer operating system component which deals with data file storage, e.g. NFS (Unix), RMS (VMS). File_Type Type Generic property for computer file types. Fill_Bottom_Depth Depth Measured depth of the bottom of the fill. (Fill : unwanted material, formation sand, proppant, gravel pack failure, workover debris ... filling up the wellbore) Fill_Height Height Height of unwanted material (formation sand, proppant, gravel pack failure, workover debris ...) filling up the wellbore Fill_Top_Depth Depth Measured depth of the top of the fill. (Fill : unwanted material, formation sand, proppant, gravel pack failure, workover debris ... filling up the wellbore) Filter_Cake_Density Density Density of the filter cake (mudcake). Filter_Cake_Photoelectric_Factor Photoelectric_Factor Photoelectric Factor of the filter cake (mudcake); often expressed in an approximation unit barns/electron. Filter_Cake_Resistivity Resistivity Resistivity of Mud Filter Cake Filter_Cake_Thickness Thickness Filter cake thickness in API test Filter_Cake_Thickness_Quality_Indicator Quality_Indicator Property used to indicate quality or confidence of data representing mud filter cake thickness. Filtered Modifier A filtering process has been applied to the data related to the property. Filtrate_CaCl2_Concentration Chemical_Concentration Filtrate CaCl2 concentration in the water phase of Oil Based Mud Filtrate_Viscosity Viscosity The viscosity of the fluid filtrate i.e the viscosity of the fluid which crossed the filtering media. Filtrate_Volume Volume Volume of filtrate, such as recovered from an API Fluid Loss test. API RP13 Section 3 Final Modifier Not to be altered or undone. Final_Transfer_Pressure Pressure Final pressure of shipping bottle Final_Transfer_Temperature Temperature Final temperature of shipping bottle Firing_Head_Type Type Type of TCP Equipment: firing head, debris sub, shock absorber, etc. First_Derivative Gradient First derivative of a scalar function Fishneck_Diameter Outside_Diameter Diameter of the fishing neck of an equipment item. Fishneck_Length Length Length of the fishing neck of an equipment item. Fissure_Storativity_Ratio Storativity_Ratio Ratio of fissure storativity to total system storativity. Usually known as Omega in reservoir dynamics. Flag Indicator An indicator of which of two or more conditions exist, or of which option has been selected. Most flags are binary in nature with a Yes/No possibility. Flattening Shape For an ellipse, the difference between the lengths of the major and minor axes divided by length of the major axis, often expressed as its inverse (Inverse_Flattening). Flattening_Depth Depth Depth at which flattening should be calculated based on the flattening feature. Flex_Joint_Angle Plane_Angle Angle between riser and blowout preventer at the flex joint. Flow_Behavior_Index Exponent The n parameter in the Power-Law and Herschel-Bulkley rheological models. The Power_Law model is "Shear_Stress=k times (Shear_Rate at the power of n)". n is dimensionless. Flow_Capacity Volume_Fraction The characteristic of a layer in a permeable system that describes the fraction of greater permeability-thicknesses for a layer with respect to the system permeability-thickness. Flow_Direction Type Indicates the flowing mode of a well completion; typically Injector or Producer. Flow_Direction_Setup Type Indicates the wellbore flow direction for which an equipment item has been configured. Flow_Head_Code Code Code for the flow head Flow_Head_Type Type Type of flow head Flow_Regime Type The flow condition of a multiphase process stream; e.g. slug, mist, or stratified flow. Flow_Type Type The type of flow of a fluid, e.g. Laminar, Pivot, etc. Flow_Unit Unit_Code Unit for fluid flow data. Flow_Velocity Velocity Flow velocity of fluid. Flowing_Condition_Depth Depth Depth at which bottomhole data were acquired Flowing_Fluid_Type Fluid_Type Type of fluid flowing into or out of a well completion: Condensate, Oil, Gas, etc. Flowing_Pressure Pressure The pressure of the flowing well measured at the intake point in the borehole. Flowrate Data_Valued_Property A measure of the volume of fluid flowing per unit time. Flowrate_Gradient Gradient A measure of the change in the flowrate of a fluid per unit length. Flowrate_Index Flowrate Unitless quantity proportional to flowrate within a given borehole environment. Flowrate indices are comparable only when the borehole and casing sizes are the same. Fluid_Compressional_Slowness Compressional_Slowness Acoustic slowness of a fluid; the slowness of the compressional wave. Fluid_Compressional_Velocity Compressional_Velocity Acoustic velocity of an acoustic (compressional) wave in fluid. Fluid_Conductivity Conductivity Conductivity of a fluid. Fluid_Contact_Type Type The type of fluid contact between Earth subsurface regions or volumes, e.g. Oil Water Contact, Gas Water Contact, etc. Fluid_Density Density Density of a fluid sample; e.g., from Borehole, Formations, Cores, etc. Also density of cement. Fluid_Level Height The level of fluid in a column or vessel, normally expressed as height above (or below) some reference point. Fluid_Loss Volume The volume of drilling fluid filtrate which is obtained in a filtration test under specific test conditions; used as an indication of the expected rate of filtrate invasion into the formation during drilling. Fluid_Marker_Type Type The type of a fluid marker depending on the fluid type occupying either side of the surface intersecting the borehole (e.g. Gas above Oil, Oil above Water, etc.) Fluid_Permeability_Factor Ratio Fraction of the fracture permeability retained at in-situ conditions after taking into account the damage due to fluid residue, function of the breaker, gel concentration and temperature at closure. Has the same effect as Proppant_Permeability_Factor. Fluid_Phase Type The phase of a fluid (gas or liquid) Fluid_Resistivity Resistivity Resistivity of a fluid. Fluid_Return_Elevation Elevation Elevation of the drill fluid return line measured from the defined elevation reference datum (normally kelly bushing or rig floor). Note that if the elevation is negative, the return line is below the elevation reference datum. Fluid_Return_Outlet Type Location of drilling fluid outlet of the circulating system. It is normally on the rig floor at the level of mud pit. In some offshore cases (conductor) it can be on the sea bed. Fluid_Sample_Origin Source General location from which a fluid sample was taken (test line, mud pit) Fluid_Temperature Temperature The temperature of a fluid (sample) under certain conditions. Fluid_Type Type The type of fluid. Usually associated with a formation, a reservoir, borehole, etc. Fluid_Viscosity Viscosity The viscosity of a fluid (sample) at specific temperature and pressure conditions. Fluid_Volume Volume Volume of fluid. Fluorine_Yield Elemental_Yield Elemental contribution of Fluorine with respect to total. Flushed_Zone_Bound_Water_Saturation Bound_Water_Saturation The extent to which the pore space in a flushed zone around the borehole contains bound water. Flushed_Zone_Bound_Water_Volume_Fraction Water_Volume_Fraction The volume fraction of bound water in the flushed zone with respect to the total volume. Flushed_Zone_Conductivity Conductivity The conductivity of the zone immediately behind the mudcake and which is considered to be flushed by mud filtrate, i.e., it is considered to have all mobile formation fluids displaced from it. Flushed_Zone_Dissolved_Salt_Volume_Fraction Volume_Fraction The volume fraction of dissolved salt in the flushed zone with respect to the total volume. Flushed_Zone_Free_Water_Volume_Fraction Water_Volume_Fraction The volume fraction of free water in the flushed zone with respect to the total volume. Flushed_Zone_Gas_Volume_Fraction Gas_Volume_Fraction The volume fraction of gas in the flushed zone with respect to the total volume. Flushed_Zone_Hydrocarbon_Volume_Fraction Hydrocarbon_Volume_Fraction The volume fraction of hydrocarbon in the flushed zone with respect to the total volume. Flushed_Zone_Irreducible_Water_Volume_Fraction Water_Volume_Fraction The volume fraction of irreducible water in the flushed zone with respect to the total volume. Flushed_Zone_OBMF_Saturation Saturation The extent to which the pore space in a flushed zone around the borehole contains oil based mud filtrate. Flushed_Zone_OBMF_Volume_Fraction Volume_Fraction The volume fraction of oil-based mud filtrate in the flushed zone with respect to the total volume. Flushed_Zone_Oil_Volume_Fraction Oil_Volume_Fraction The volume fraction of oil in the flushed zone with respect to the total volume. Flushed_Zone_Resistivity Resistivity Resistivity of the formation flushed zone (that portion of the formation in which the movable fluids are considered to have been completely replaced by mud filtrate during drilling). Flushed_Zone_Water_Saturation Saturation The extent to which the pore space in a flushed zone around the borehole contains water. Flushed_Zone_Water_Volume_Fraction Water_Volume_Fraction The volume fraction of water in the flushed zone with respect to the total volume. Flux_Leakage Data_Valued_Property The proportion of magnetic flux forced out of the pipe by the distortion of the field caused by the presence of a discontinuity Fold_CDP Count Number of traces stacked at a CDP. Fold_Type Type Type of fold (e.g., Rollover) Force Data_Valued_Property An agency or influence that if applied to a free body results chiefly in an acceleration of the body and sometimes in elastic deformation and other effects. Foreign_System Type Type of seismic system: Charisma, IESX Format Type General plan of organization or arrangement, such as for a computer data file or for the presentation of data. Formation_Compressive_Strength Compressive_Strength The compressive strength of an earth formation. Formation_Conductivity Conductivity Formation Conductivity Formation_Damage_Skin Skin_Factor The skin effect caused by mechanical or chemical formation damage such as invasion of drilling fluids, migration of fine material, wettability change, scale deposit or bacteria. The annular volume damaged is called the Damaged Zone. Formation_Name Name Name given to a geologic formation; may be a local name or an accepted standard. Formation_Resistivity Resistivity True Formation Resistivity Formation_Resistivity_Factor Ratio Ratio of the resistivity of water-saturated rock to that of the water solution contained in the rock. Also called Formation Resistivity Factor and abbreviated "F". Formation_Resistivity_Sw100 Resistivity Resistivity of formation, assuming 100% water-saturated. Formation_Stiffness_Factor Data_Valued_Property Dimensionless estimate of the formation stiffness, i.e., ratio between the applied pressure and the displacement of the formation. Formation_System_Type Type Formation system assigned by the client Formation_Temperature Temperature Temperature of the (earth) formations. Formation_Volume_Factor Volume_Fraction The ratio of the volume occupied by a fluid at specified conditions, such as reservoir conditions, to the volume which would be occupied at standard conditions. Formula Description Symbolic expression of a rule or principle. Fossil_Genus Genus Name for genus of fossil within some group. Fossil_Group Group Name for biological group of fossils. Fossil_Species Species Name for species of fossil within some genus. Fossil_Type Type Type of fossil (animal or plant remnant from past geological ages, preserved in the earth's crust) Fraction_Above_Depth_Point Ratio Unitless fraction of an image that is displayed above the depth associated with the image. Fractional_Surface_Area Data_Valued_Property The fraction of a clays specific surface area which participates in hydraulic flow. Fracture_Azimuth Azimuth The azimuth of a fracture usually in an interval of the borehole. Fracture_Bridging_Factor Ratio Ratio of fracture width to mean proppant diameter (Industry usage: 2.5.) below which bridging will occur (proppant cannot move through the fracture). Fracture_Closure_Pressure Pressure Magnitude of the stress required to open a preexisting fracture. Assumed to be equal to the least principal stress which acts perpendicular to the face of the fracture, trying to keep it closed. Above it, the fracture is open, closed below. Fracture_Closure_Time Time_Interval Time required by a hydraulic fracture to close. Can be derived from a Nolte plot (pressure vs. time). The more fluid that fluid leaks off into the formation, the faster the fracture closes. Fracture_Condition Type Characterizes the condition of the fracture with respect to its void space; e.g. Open, Closed, Vuggy, etc. Fracture_Conductivity Conductivity Fracture permeability - width product of a finite conductivity vertical or horizontal fracture. Fracture_Density Data_Valued_Property Density of fracture occurrence, often measured as a function of linear trace length of fractures observed in a given surface area. Fracture_Element_Distribution_Type Type Type of spatial variation (linear or elliptical) of fracture height, width and conductivity Fracture_Element_Height Height Height of fracture element Fracture_Element_Width Width Width of fracture element Fracture_Face_Skin Skin_Factor The skin along the face of the fracture (natural or hydraulic). Fracture_Geometry Geometry Characterizes the geometry of a fracture: Planar or Linear. Fracture_Half_Length Length The length of one wing of a fracture, from the bore hole to one of its ends. Fracture_Height Height Height of a fracture. Fracture_Length Length The length of one wing of a fracture. Fracture_Normal_Weakness Ratio The ratio of normal compliance of the fracture to the total normal compliance of the fractured rock. It indicates how much of the total compliance of the fractured rock is due to the fractures. See Compliance. Fracture_Orientation Azimuth The orientation of a fracture relative to north. Fracture_Origin Type Characterizes the origin of a fracture i.e. natural (inherent) or induced. Fracture_Plausibility Probability Estimate of the likelihood that a given rock body is fractured. Fracture_Pressure Pressure Fluid pressure in the wellbore required to undergo hydraulic fracturing. Fracture_Pressure_Gradient Pressure_Gradient Ratio of the Frac Pressure to the true vertical depth. Typical values for a reservoir range from 0.4-0.6 psi/ft for a depleted reservoir to 0.8-1.0 psi/ft for deep high pressure formation. Fracture_Pressure_Safety_Factor Safety_Factor Amount by which borehole pressure should remain below fracture pressure, to allow for uncertainty in fracture pressure estimation. Fracture_Shear_Weakness Ratio The ratio of shear compliance of the fracture to the total shear compliance of the fractured rock. It indicates how much of the total compliance of the fractured rock is due to the fractures. See Compliance. Fracture_Spacing Width The distance between adjacent fractures. Fracture_Storativity Storativity Fracture Storativity (Porosity * Total Compressibility product) of a finite conductivity vertical fracture ("(phi*Ct)f") Fracture_Toughness Strength Measure of the rock resistance to crack propagation (Hydraulic Fracturing). Must not be confused with tensile strength. Obtained by compressing a slice of core with a central hole. Expressed as Pressure times square root of length. Fracture_Type Type Type of formation fracture. Fracture_Width Width Width of a fracture. Fracturing_Efficiency Efficiency Ratio of Fracture Volume at end of job to Total Volume Pumped. The difference between the two volumes represents the volume which leaked off into the formation. Frame_Bulk_Modulus Bulk_Modulus The bulk modulus of the solid frame of the rock. The solid frame of the rock includes the porosity but not the content of the pore spaces. Frame_Density Density Bulk density of the solid frame of the rock. The solid frame of the rock includes the porosity but not the content of the pore spaces. Frame_Density = (1 - Porosity) * Grain_Density. Frame_Number Ordinal_Number Multi-source/multi-receiver shot record identifier Frame_Shear_Modulus Shear_Modulus The shear modulus of the solid frame of the rock. The solid frame of the rock includes the porosity but not the content of the pore spaces. Free_Fluid_Index Data_Valued_Property The proportion of the bulk volume of the formation which is occupied by fluids which are free to flow; commonly abbreviated FFI, measured using nuclear magnetic resonance techniques. Free_Gas_Oil_Ratio Gas_Oil_Ratio The ratio of the volume of free gas to the volume of oil for a reservoir fluid at standard conditions. Free_Water_Level Depth Depth at which the water pressure and oil/gas pressure are equal; the depth at which Pc (capillary pressure) is equal to 0. Frequency Data_Valued_Property The repetition rate of a periodic waveform. The inverse of period. Friction_Angle Plane_Angle Angle relating the increase in shear strength with compressive strength. Friction_Coefficient Ratio Ratio of the frictional (tangential) force to the contact (normal) force between two objects or materials in contact. From_Conn_Number Ordinal_Number Indicates which end (1 or 2 for tubulars, 3 for a hydraulic tee,...) of the "From" equipment is connected to the "To" equipment From_Datum_Code Geodetic_Datum_Code Code of the source datum used in a datum-to-datum coordinate system transformation (datum shift). From_Entity_Code Entity_Code Code of Entity from which the relationship originates. From_Mounting_Location Location Location of the from Equipment in a From-To connection : Inside, Outside, Top, Bottom. If A is mounted on top of B in the borehole and if From_Id=A, To_Id=B, then From_Mouting_Location=Top. If Packer P is set inside casing C, with From_Id=P, To_Id=C then From_Mouting_Location=Inside From_Offset Length The distance from the mid-point of the "From" equipment to the bottom of the "To" equipment in a From_To connection. From_Property_Code Property_Code Code of Property of Entity from which the relationship originates. Function_Name Name Name of a software program function. Fundamental_Strength Strength The stress a material is able to withstand under a given set of conditions (temperature, pressure, solution, etc.) without deforming continuously. Funnel_Viscosity Viscosity Time needed for a given quantity of fluid (generally a quart of mud) to flow into a specified size funnel (3/16 inch id tube of a 12 inch long funnel). Used for drilling fluids. GPD_Lithology_Pattern Name Name of the GPD pattern used to draw the lithology. GQI_Admission_Policy Processing_Option Identifies the Geometry Query Interface (GQI) policy for maintaining the content of a geometric feature as it is edited. The most common value is POINT_SET_PRESERVING, but applications may implement others so the values are not constrained. Gadolinium_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of gadolinium to total dry weight Gadolinium_Yield Elemental_Yield Elemental contribution of Gadolinium with respect to total. Gain Data_Valued_Property An increase in amplitude or power from one point in a system to another, such as between input and output. Gamma_Ray Data_Valued_Property The intensity of natural gamma-ray radiation emitted from formations containing radioactive elements, such as Potassium, Thorium, and Uranium. Measured according to API specifications. Gamma_Ray_Data_Density MWD_Data_Density Density of data samples per length of borehole traversed, for a gamma ray logging measurement. Gamma_Ray_Minus_Uranium Gamma_Ray The measurement of the naturally occurring gamma radiation less the radiation attributed to uranium. Gamma_Ray_Time_After_Bit Time_After_Bit In MWD/LWD logging, the time delay between the drill bit and a gamma ray sensor reaching a given point in the wellbore. Gap_Length Interval_Length The length of gap usually detected in some pattern or geological feature. The length is usually an interval length like depth. Gas_Acoustic_Velocity Acoustic_Velocity Sound velocity of gas at reservoir pressure and temperature. Typical value is 200 m/s. Gas_Compressibility Compressibility Change in gas volume per unit volume per change in pressure (dV/V.dp) at a given pressure and temperature. Gas_Density Density Density of gas (air, hydrocarbon, etc.) at a particular temperature and/or pressure; e.g., gas density at well bottomhole conditions or at well surface conditions. Gas_Description_Type Type Type of data describing the gas: complete hydrocarbon composition, impurities (H2S, CO2,N2) or gas gravity. Gas_Deviation_Factor Coefficient Dimensionless quantity expressing how a gas deviates from perfect gas law, commonly expressed by PV=ZnRT. Sometimes named Gas Compressibility Factor, but NOT the same as Gas_Compressibility. Z usually varies from 0.7 to 1.2. Gas_Differential_Pressure Differential_Pressure Gas differential pressure across the orifice plate when a sample is taken Gas_Flag Flag Flag indicating presence of gas Gas_Flow_Velocity Flow_Velocity Flow velocity of gas component of fluid. Gas_Flowrate Flowrate Rate of flow of gas Gas_Fluid_Ratio Volume_Fraction The ratio of gas within a fluid otherwise named foam quality when the gas is used to foam the fluid. Gas_Formation_Volume_Factor Formation_Volume_Factor Ratio of gas volume at specified (typically, reservoir) conditions to the gas volume at surface (stock tank) conditions. Normally abbreviated Bg. Gas_Fraction Volume_Fraction Volumetric fraction of gas in the total fluid Gas_Gravimeter_Type Type Type of instrument used to measure gas gravity Gas_Gravity Specific_Gravity The ratio of the molecular weight of the gas to that of air Gas_Holdup Holdup Volume fraction of gas in the upward-moving stream of a producing well. Gas_Line_Diameter Diameter Diameter of the gas line Gas_Line_Pressure_Gauge_Type Type Gauge used to measure gas meter pressure Gas_Line_Temperature_Gauge_Type Type Gauge used to measure gas meter temperature Gas_Liquid_Ratio Volume_Fraction Volume ratio of gas to liquid (oil + water) in a volume of fluid. Gas_Mass_Flowrate Mass_Flowrate Mass flowrate of gas. Gas_Meter_Type Type Type of meter used to measure gas flowrate Gas_Metering_Line_Size Diameter Line size of gas meter inlet and outlet pipe Gas_Oil_Ratio Volume_Fraction A measure of the volume of gas which is produced with a given quantity of oil. Gas_Pressure_Axis_Type Type One of the pressure transformations used in Gas Well Interpretation Gas_Probability Probability The probability that gas is present in the formation. Gas_Sampling_Point Location The location where gas samples are taken on the separator Gas_Saturation Saturation The extent to which the pore space in a formation contains gas. Gas_Saturation_At_Breakthrough Gas_Saturation Gas saturation at the breakthrough point. In Special Core Analysis, breakthrough is the appearance of the injected fluid at the outlet face of the rock sample. Gas_Saturation_Min_So_3Phase Gas_Saturation The gas saturation at minimum oil saturation in a three phase system. (SCAL SGM) Gas_Sorption_Storativity_Ratio Ratio Ratio of the stored gas in the kerogen (solid hydrocarbon) to the total gas stored in the system Gas_Viscosity Viscosity The viscosity of a gas at specific temperature and pressure conditions. Gas_Volume_Fraction Volume_Fraction The volume fraction of gas with respect to the total volume; the product of Porosity and Gas_Saturation Gas_Water_Contact_Depth Depth Depth at which the gas water contact has been identified in a Reservoir Unit Gas_Water_Solubility Solubility Measure of the degree to which a gas is soluble in water, often designated Rs Water Gauge_Count Count Number of gauges Gauge_Length Length Length of the in-gauge portion of an equipment item. Gauge_Pressure Pressure Pressure above one atmosphere. Gel_Concentration Concentration Concentration of gelled fluid (fracturing gel, gelled acid ...) Gel_Temperature Temperature Temperature of gelled fluid (fracturing gel, gelled acid ...) General_Weather_Description Description Description of current weather conditions. Genus Biological_Name A category of biological classification ranking between the family and the species. A class, kind, or group marked by one or more common characteristics. Geocentric_Dx Displacement X component of the translation of the center of a geodetic datum. One of seven parameters used in the Bursa-Wolf transformation. Geocentric_Dy Displacement Y component of the translation of the center of a geodetic datum. One of seven parameters used in the Bursa-Wolf transformation. Geocentric_Dz Displacement Z component of the translation of the center of a geodetic datum. One of seven parameters used in the Bursa-Wolf transformation. Geocentric_Rx Rotation Rotation of the geocentric Cartesian coordinate system about its X axis. One of seven parameters used in the Bursa-Wolf transformation. Geocentric_Ry Rotation Rotation of the geocentric Cartesian coordinate system about its Y axis. One of seven parameters used in the Bursa-Wolf transformation. Geocentric_Rz Rotation Rotation of the geocentric Cartesian coordinate system about its Z axis. One of seven parameters used in the Bursa-Wolf transformation. Geocentric_Scale_Factor Scale_Factor Scale factor used in the Bursa-Wolf transformation. Geodetic_Coord_Sys_Code Code Type of a geodetic coordinate system. This property specifies whether the Geodetic coordinate system used to record position data is Cartesian or Latitude/Longitude. Geodetic_Coord_Sys_Name Name Name of a geodetic coordinate system. Geodetic_Datum_Code Code Code of the reference system that describes the position, orientation and scale relationship of the ellipsoid and the earth, such that referenced coordinates are unique. Geodetic_Datum_Name Name Name of the reference system that describes the position, orientation and scale relationship of the ellipsoid and the earth, such that referenced coordinates are unique. Geodetic_Datum_Point Name Name of Origin of Geodetic Datum Geodetic_Datum_Point_Latitude Latitude Latitude of Origin of Geodetic Datum Geodetic_Datum_Point_Longitude Longitude Longitude of Origin of Geodetic Datum Geographic_Location Location Geographical location, either the nearest city or geographical spot or a free text telling where the location is. Geologic_Age Absolute_Time The geochronologic age of an item or event, such as an earth layer. This is usually the average age in millions of years (Ma). Geologic_Age_Code Code Reference code of a geologic age; e.g., Paleozoic, Permian, etc. classified according to the type of geologic age unit (Era, Epoch, etc.). Geologic_Age_Type Type Type of geologic age unit; e.g., Era, Period, Epoch, Age. Geologic_Flag Flag Flag indicating that the object or data pertains to geology or was derived from geologic data. Geological_Influence_Type Type The type of geological influence that dominates some feature such as a sedimentary channel, e.g. Wave dominated, Delta dominated, etc. Geometric_Mean_Permeability Permeability Mean permeability in horizontal or vertical plane, computed as the square root of the product of the normal directional permeability values (e.g. X-Y or Y-Z) in the plane. Geometrical_Factor Data_Valued_Property A geometry-dependent weighting factor used to characterize how different media in the neighborhood of a sensor participate in the sensor measurement. Geometry Data_Valued_Property The geometry of an object; e.g. the geometry of an Earth formation, a Fault, a Field, a Basin, a Borehole, etc. Usually represented with a Grid, Mesh, Parametric curves, or other complex representations. Geophone_Type Type Type of geophone, used to detect particle motion associated with the passage of a seismic wave. Geopolitical_Region_Code Code The code/name given to a geopolitical region, e.g. Nation, State, County, Province, Community, etc. Geopolitical_Region_Type Type The type of a geopolitical region, e.g. Nation, State, County, Province, Community, etc. Geothermal_Gradient Thermal_Gradient The rate of change of temperature with depth in the Earth. It averages about 30 degC/km at shallow depths. Get_Function_Name Function_Name Name of function used to read data. Glauconite_Volume_Fraction Volume_Fraction The volume fraction of glauconite with respect to the total volume. Gooseneck_Radius Curvature_Radius Radius of the gooseneck in a Coil Tubing Unit, along which the tubing is bent; used in the fatigue model Grade Data_Valued_Property A rating of some sort given to an item (e.g., equipment) by some standards organization as the API, the IADC, etc. Gradient Data_Valued_Property The change in the value of a quantity per unit distance in a specified direction. Grading_Date Date Date on which the grading of equipment condition or state took place. Grain_Density Density The density of a unit volume of a mineral or other rock material at zero porosity. Sometimes called Matrix Density. Grain_Distribution Description Textual description of the grain distribution in a rock sample. Grain_Size Diameter Average diameter of a mineral grain or set of grains. Granulometric_Sequence_Type Type This property specifies whether the granules making up a Earth subsurface sequence are coarsening up or fining up. Graphic_Symbol_File_Name File_Name Graphic symbol file specification. [In GeoFrame, this is typically a GPD file, e.g., gpd_lib/stop_symbol.gpd] Graphic_Symbol_Name Name Name assigned to a graphic symbol. Graphical_File File_Name Name of file containing related graphical information Gravel_Packed_Perforation_Length Perforation_Length Length of the portion of the perforation which is filled with Gravel Pack material. Gravity Acceleration Strength of the gravitational field at some location. Also referred to as the acceleration of gravity, measured in units of acceleration. Gravity_Bladeface Bladeface In directional drilling, the angle between Top of Hole and a sensor contained in a stabilizer blade; used in hole sections of high deviation. Measurement is from -180 to +180 degrees. Gravity_Toolface Toolface In directional drilling, the angle between Top of Hole and a reference direction on the drill string (e.g. Y-Axis accelerometer); used in hole sections of high deviation. Measurement is from -180 to +180 degrees. Great_Circle_Axis Plane_Angle The pole to a plane represented by a great circle. Great_Circle_Azimuth Azimuth The azimuth of a plane represented by a great circle. Great_Circle_Dip Dip_Angle The dip of the plane represented by a great circle. Grid_Convergence_Angle Plane_Angle Angle to be used in converting azimuths between true north and grid north or the Y axis of the cartographic projection. [Geoshare convention: True Azimuth = Grid Azimuth + Grid_Convergence_Angle] Gross Modifier Unrefined. Gross_Area Surface_Area Gross area of a region such as that of a lease parcel or covered by a lease agreement. Gross_Cutoff_Absent_Fraction Quality_Indicator Fraction of the summation interval for which data to apply "Initial" cutoff criteria are unavailable; used as a coarse indicator of the reliability of the summation results. Gross_Porosity Porosity The average porosity in a gross thickness interval or a group of intervals. Gross_Thickness Thickness Total thickness of a zone or a collection of zones, including portions which may not be of interest; may still be subject to discriminator cutoffs specified as "Initial". Group Biological_Name An assemblage of related organisms - often used to avoid taxonomic connotations when the kind or degree of relationship is not clearly defined. Group_Velocity Acoustic_Velocity The velocity with which the energy in a wavetrain travels. In dispersive media, it is the velocity of the envelope of the wavetrain. Gypsum_Volume_Fraction Volume_Fraction The volume fraction of gypsum with respect to the total volume. H2S_Concentration Chemical_Concentration Concentration of H2S generally measured in ppm. H2S concentration is critical in evaluating the corrosion of metal (e.g. coiled tubing) under stresses. H2S_Flag Flag Indicates that hydrogen sulfide (H2S) has been detected. H2S_Mole_Fraction Mole_Fraction Mole fraction of Hydrogen Sulfide to total gas composition H2S_Service_Flag Flag Specifies whether equipment is for H2S service or not H2S_Service_Type Type Type of H2S corrosion service capability, e.g., Proof or Resistant HGS_Concentration Solids_Concentration High gravity solids Concentration HGS_Removal_Efficiency Efficiency Ratio of mass rate of HGS (high Gravity Solid) discarded through the underflow of a piece of SCE (Solids Control Equipment) to the mass rate of HGS fed into it HTHP_Filter_Cake_Thickness Filter_Cake_Thickness Thickness of filter cake produced under high temperature, high pressure (HTHP) conditions. HTHP_Filtrate_Volume Filtrate_Volume Volume of filtrate produced under high temperature, high pressure (HTHP) conditions. Halite_Volume_Fraction Volume_Fraction The volume fraction of halite with respect to the total volume. Heat Energy Energy that causes substances to rise in temperature, fuse, evaporate, expand, or undergo any of various other related changes. Heat_Capacity Data_Valued_Property The amount of heat required to raise the temperature of a unit volume of a given material by one degree. Heat_Exchanger_Code Code Code for heater used in testing and production services Heat_Flux Data_Valued_Property The quantity of thermal energy which passes through a cross-sectional area per unit time. Heat_Release_Rate Data_Valued_Property The quantity of heat released in a material per unit time. Also known as mixing power. Heat_Transfer_Coefficient Data_Valued_Property Amount of heat transferred per unit time per degree per unit area. Heater_Type Type Heater type Heavy_Phase_Flow_Velocity Flow_Velocity Flow velocity of heavy phase component of fluid. Height Length The distance from the bottom to the top of something standing upright. Also, the extent of elevation above a level. Hemisphere Type Code of the earth hemisphere (Northern or Southern) in which this projection is located. Heterogeneity_Cosine_Of_Phase Reflection_Heterogenity Measure of heterogeneity computed from the Cosine of Phase trace over a given interval. Heterogeneity_Instantaneous_Frequency Reflection_Heterogenity Measure of heterogeneity computed from the Instantaneous Frequency trace over a given interval. Heterogeneity_Instantaneous_Phase Reflection_Heterogenity Measure of heterogeneity computed from the Instantaneous Phase trace over a given interval. Heterogeneity_Reflection_Strength Reflection_Heterogenity Measure of heterogeneity computed from the Reflection Strength trace over a given interval. Heterogeneity_Seismic_Amplitude Reflection_Heterogenity Measure of heterogeneity computed from the Seismic Amplitude trace over a given interval. Hierarchical_Flag Flag Flag indicating that the entities participate in a hierarchy. High Modifier Of greater degree, size, amount, or content than average or ordinary. Of relatively great importance. Advanced in complexity, development, or elaboration. Holdup Volume_Fraction In a producing well, the volume fraction of a specific fluid phase in the upward-moving stream. The relative quantities of fluids produced are related to the holdup and upward velocity of each phase. Holdup_Index Holdup Unitless quantity proportional to holdup within a given borehole environment. Holdup indices are comparable only when the borehole and casing sizes are the same. Hole_Azimuth Azimuth The angle between a vertical plane tangent to the borehole and north. Hole_Condition_Type Type The type of a borehole condition. Hole_Deviation Deviation Angle between the borehole axis and the vertical (also known as the Drift Angle and, in the drilling industry, Inclination). Hole_Inside_Diameter Inside_Diameter The effective inside diameter of a Well; may be of the Borehole, Casing or Tubing. Hole_Rotation_Friction_Coefficient Friction_Coefficient Friction coefficient between open hole and drill string in rotation Hole_Sliding_Friction_Coefficient Friction_Coefficient Friction coefficient between open hole and drill string in sliding (translation only) operating mode Hole_Translation_Friction_Coefficient Friction_Coefficient Vertical component of the Friction coefficient between open hole and drill string during an helical movement, e.g., reaming mode Hook_Load Load The downward force exerted on the hook of the traveling block by the suspended equipment (drillstring, casing, etc.) Horizon_Sample_Count Count Number of horizon samples to use while smoothing. Horizon_Tracking_Event Type Type of waveform event identified by the Horizon (crossing +/-, crossing -/+, peak, trough) Horizon_Type Type The type of a Horizon in the Earth subsurface, e.g. Seismic or Geological Horizontal_Formation_Resistivity Formation_Resistivity Formation resistivity measured parallel to layering. (for "Transverse-Isotropic (TI)" rock" Horizontal_Mean_Permeability Geometric_Mean_Permeability Geometric mean permeability in the horizontal plane (X-Y) of the reservoir. Horizontal_Mobility Mobility A measure of the ease with which a fluid can be moved horizontally in a specific medium (i.e. rock). The ratio of the effective horizontal permeability and the viscosity of the fluid. Horizontal_Permeability Directional_Permeability A permeability oriented horizontally along the bedding plane of the stratum. Usually abbreviated as Kx. Horizontal_Size Diameter The size of any object as measured horizontally Horizontal_Well_Flowing_Length Length Total Horizontal Well Flowing Length Horizontal_Well_Standoff Reservoir_Distance Distance from Horizontal Well to bottom of the Hydraulic Unit Host_Identifier System_Identifier Identification of a host computer system where, for example, an application is to run. Housing_Number Identifier Identifying number often etched onto the housing. Hydraulic_Diffusivity Diffusivity The characteristic of a rock-fluid system that describes the relationship of pressure change in time to pressure gradient. It is defined as permeability divided by the product of porosity, fluid viscosity and fluid compressibility. Hydraulic_Drive_Pressure Pressure Pressure of the hydraulic fluid delivered to an Hydraulic motor Hydraulic_Drive_Temperature Temperature Temperature of the hydraulic fluid delivered to an Hydraulic motor Hydraulic_Fracture_Stage Status Whether the fracture is considered after closure or at the end of job. Hydraulic_Model_Type Type Type of Flow Behavior for the Hydraulic Unit, including the Inner Boundary Type + Reservoir Behavior Type + Outer Boundary Type Hydraulic_Power Power Power produced or available from a system due to fluid flow, such as for pumps and turbines. Hydraulic_Unit_Top_To_Flowing_Top Reservoir_Distance Distance from Top of Hydraulic Unit to Top of Flowing Interval Hydraulic_Unit_Top_To_Perforation_Top Reservoir_Distance Distance from Top of Hydraulic Unit to Top of Perforation Hydrocarbon_Density Density Density of hydrocarbons. Hydrocarbon_Flowrate Flowrate Rate of flow of hydrocarbons (oil, gas and condensate) Hydrocarbon_Pore_Volume Pore_Volume The pore volume of a reservoir occupied by hydrocarbons in either the vapor or liquid phase. Hydrocarbon_Saturation Saturation The fraction of pore volume filled with hydrocarbons. Hydrocarbon_Volume_Fraction Volume_Fraction The volume fraction of hydrocarbon with respect to the total volume; the product of porosity and hydrocarbon saturation Hydrogen_Index Data_Valued_Property The ratio of the number of hydrogen atoms per unit volume of a material to that number in pure water at 75 degF. Neutron logging response depends mainly on hydrogen index. Hydrogen_Mole_Fraction Mole_Fraction Mole fraction of Hydrogen to total gas composition Hydrogen_Yield Elemental_Yield Elemental contribution of Hydrogen with respect to total. Hydrophone_Type Type Type of geophone, used to detect pressure changes associated with the passage of a seismic wave. Hydrostatic_Pressure Pressure Pressure due to the weight of a column of liquid (formation water, drilling mud, etc.) extending from the depth of interest to the liquid level. IADC_Code Type International Association of Drilling Contractor Code, used for drill bits. IADC_Grade_Bearing_Seals Drill_Bit_Grade_IADC IADC Drill Bit Grade based on condition of bearing seals IADC_Grade_Dull Drill_Bit_Grade_IADC IADC Drill Bit Grade based on dullness characteristics IADC_Grade_Gauge Drill_Bit_Grade_IADC IADC Drill Bit Grade based on gauge IADC_Grade_Inner_Rows Drill_Bit_Grade_IADC IADC Drill Bit Grade based on condition of inner rows IADC_Grade_Location Drill_Bit_Grade_IADC IADC Drill Bit Grade - Location IADC_Grade_Other Drill_Bit_Grade_IADC IADC Drill Bit Grade based on other characteristics IADC_Grade_Outer_Rows Drill_Bit_Grade_IADC IADC Drill Bit Grade based on condition of outer rows IADC_Grade_Reason_Pulled Drill_Bit_Grade_IADC IADC Drill Bit Grade based on reason for pulling bit. IPR_Fluid_Flow_Model_Type Type Type of Inflow Performance Behavior for the Hydraulic Unit (Darcy, Forcheimer, Vogel, Cheng) Id Relation_Valued_Property A system generated number that uniquely identifies an data item (Entity, Property, Representation, ...) within certain system imposed limitations on the uniqueness. Ideal_Receiver_Position_0 Rectangular_Position Idealized receiver position 0 Ideal_Receiver_Position_0_X_Coord X_Coordinate X-coordinate of ideal receiver position 0. Ideal_Receiver_Position_0_Y_Coord Y_Coordinate Y-coordinate of ideal receiver position 0. Ideal_Receiver_Position_0_Z_Coord Z_Coordinate Z-coordinate of ideal receiver position 0. Ideal_Receiver_Position_1 Rectangular_Position Idealized receiver position 1 Ideal_Receiver_Position_1_X_Coord X_Coordinate X-coordinate of ideal receiver position 1. Ideal_Receiver_Position_1_Y_Coord Y_Coordinate Y-coordinate of ideal receiver position 1. Ideal_Receiver_Position_1_Z_Coord Z_Coordinate Z-coordinate of ideal receiver position 1. Ideal_Receiver_Position_2 Rectangular_Position Idealized receiver position 2 Ideal_Receiver_Position_2_X_Coord X_Coordinate X-coordinate of ideal receiver position 2. Ideal_Receiver_Position_2_Y_Coord Y_Coordinate Y-coordinate of ideal receiver position 2. Ideal_Receiver_Position_2_Z_Coord Z_Coordinate Z-coordinate of ideal receiver position 2. Ideal_Sample_Shift_0 Time_Interval Fractional sample shift associated with ideal position 0 Ideal_Sample_Shift_1 Time_Interval Fractional sample shift associated with ideal position 1 Ideal_Sample_Shift_2 Time_Interval Fractional sample shift associated with ideal position 2 Ideal_Source_Position_0 Rectangular_Position Idealized source position 0 Ideal_Source_Position_0_X_Coord X_Coordinate X-coordinate of ideal source position 0. Ideal_Source_Position_0_Y_Coord Y_Coordinate Y-coordinate of ideal source position 0. Ideal_Source_Position_0_Z_Coord Z_Coordinate Z-coordinate of ideal source position 0. Ideal_Source_Position_1 Rectangular_Position Idealized source position 1 Ideal_Source_Position_1_X_Coord X_Coordinate X-coordinate of ideal source position 1. Ideal_Source_Position_1_Y_Coord Y_Coordinate Y-coordinate of ideal source position 1. Ideal_Source_Position_1_Z_Coord Z_Coordinate Z-coordinate of ideal source position 1. Ideal_Source_Position_2 Rectangular_Position Idealized source position 2 Ideal_Source_Position_2_X_Coord X_Coordinate X-coordinate of ideal source position 2. Ideal_Source_Position_2_Y_Coord Y_Coordinate Y-coordinate of ideal source position 2. Ideal_Source_Position_2_Z_Coord Z_Coordinate Z-coordinate of ideal source position 2. Identifier Data_Valued_Property A number, label or code given to an object in an attempt to uniquely identify it. Idle_Time Time_Interval Period of time during which equipment is idle. Complement of Operating_Time. Igneous_Volume_Fraction Volume_Fraction The volume fraction of igneous rock with respect to the total volume. Illite_Volume_Fraction Volume_Fraction The volume fraction of illite with respect to the total volume. Illuminance Data_Valued_Property The intensity of light striking a surface. Image_Clipping_Region Data_Valued_Property Vector of pixel values indicating which portion of an input image is represented in a clipped output; the structure of the vector is [Offset from Top, Offset from Left, Height, Width]. Image_Origin_Azimuth Azimuth The azimuth of a point on an object corresponding to the origin of an image of the object (left side of core image) Impedance Data_Valued_Property The measure of the ability of an object or medium to resist the flow of electric current. Impedance is a complex quantity composed of a real term (Resistance) and an imaginary term (Reactance). Impedance_Factor Data_Valued_Property Impedance Factor Implementation_Code Code Catalog code of the Implementation of a Representation In_Service_Date Date The date on which an equipment item or product was placed in service. Incident_Angle Plane_Angle The angle which the raypath of an incident ray makes with the perpendicular to the interface. In an isotropic medium, it is the same as the angle that a wavefront makes with the interface. Inclination Plane_Angle The vertical angle between a line and the horizontal; has historically been used in the drilling industry to mean the angle between the borehole path and vertical (the term Hole_Deviation is preferred for this concept). Inclination_Build_Rate Curvature The rate of change in inclination expressed in degrees per unit of course length. Inclination_Error Error Plus or minus inclination error of sensor Included Flag A flag indicating whether an object is included or excluded from the spatial extent of a containing object. Inclusion_Proportion Proportion Percentage of rocks occupied by inclusions within a given depth interval Inclusion_Type Type The type of inclusions in a rock e.g. pebble, nodules, etc. Index_Type Type Type of index for indexed data, such as Measured Depth (MD), True Vertical Depth (TVD), etc. Indicator Data_Valued_Property Property which indicates presence of some entity, occurrence or condition, or which quantifies some condition, often as a proportion of some local reference value. Often called _Factor or _Coefficient. Inductance Data_Valued_Property The capability of an electric circuit to induce an electromotive force (emf) within the circuit. Inductive_Reactance Reactance The component of electrical impedance due to inductance. Inertial_Flow_Coefficient_Correlation_Type Type Inertial Flow Coefficient Correlation (e.g. Saucier, Firoozabadi, etc. ) Inertial_Flow_Correlation_Coef Data_Valued_Property Cooke's inertial fracture flow correlation coefficient (b). Empirical coefficient relating Fracture inertial flow coefficient Beta to Fracture permeability. Non RP66 Unit Inertial_Flow_Correlation_Exponent Data_Valued_Property Cooke's inertial fracture flow correlation exponent (a). Empirical coefficient relating Fracture inertial flow coefficient Beta to Fracture permeability. Inetgrated_Transit_Time Transit_Time Acoustic transit time computed by integrating acoustic slowness measurements (from a sonic log) over a depth interval. Initial Modifier Of or relating to the beginning. Initial_Amount Amount Initial amount. Usually used to quantify the initial amount of some material. Initial_Final_Wellbore_Storage_Ratio Ratio Ratio of early-time (initial) to final wellbore storage factor ("Ca/C") Initial_Gas_Oil_Ratio Gas_Oil_Ratio Gas-Oil Ratio at the beginning of the production. Initial_Gas_Saturation Gas_Saturation Gas Saturation at the beginning of the test, experiment or production. Initial_Gas_Volume Volume Volume of gas accumulated prior to the beginning of the measurement period. Initial_In_Situ_Gas_Volume Volume Total volume of in situ gas in the reservoir. Initial_In_Situ_Oil_Volume Volume Total volume of in situ oil in the reservoir. Initial_Oil_Saturation Oil_Saturation Oil Saturation at the beginning of the test, experiment or production. Initial_Oil_Volume Volume Volume of oil accumulated prior to the beginning of the measurement period. Initial_Reservoir_Pressure Pressure Initial reservoir pressure, before any production or injection occurs, normally abbreviated Pi; sometimes taken as the pressure at the external boundary of the drainage area. Initial_Reservoir_Pressure_Date Date Date when initial reservoir pressure data were recorded Initial_Reservoir_Pressure_Depth Depth Depth reference of initial reservoir pressure Initial_Reservoir_Pressure_Temperature Temperature Temperature taken when initial reservoir pressure recorded Initial_Water_Saturation Water_Saturation Water Saturation at the beginning of the test, experiment or production. Initial_Water_Volume Volume Volume of water accumulated prior to the beginning of the measurement period. Injected_Fluid_Type Fluid_Type Type of fluid injected. Injection_Point Type Indicates where a fluid is injected in the main flow e.g. Low Pressure Discharge... Injector_Head_Weight Weight Weight of the injector head of a coiled tubing unit Inlet_Connection_Size Diameter The connection size of the input line to the equipment Inlet_Flowrate Flowrate Flow Rate at the inlet of an equipment (e.g. suction side of a pump) Inlet_Pressure Pressure Pressure at the inlet of an equipment item. Inline_Dip Dip_Angle Angle that a surface, e.g. a bedding or fault surface, makes with the horizontal, measured in the in-line direction. Inner_Boundary_Condition_Type Type Description of the inner boundary condition for a well test model. Inner_Outer_Storativity_Ratio Storativity_Ratio Radially composite system storativity ratio [inner/outer bank] Inner_Pipe_Outside_Diameter Outside_Diameter Outer diameter of the inner pipe Inside_Diameter Diameter Inside diameter of an entity, such as an item of drillstring equipment Instantaneous_Amplitude Analytic_Trace Amplitude component of an analytic seismic trace, when decomposed into amplitude and phase components (absolute value). Instantaneous_Frequency Analytic_Trace Time derivative of Instantaneous_Amplitude. Instantaneous_Frequency_Slope Slope Least squares slope (gradient) of instantaneous frequency in an interval. Instantaneous_Phase Analytic_Trace Phase component of an analytical seismic trace when decomposed into amplitude and phase components (Hilbert transform technique) Instantaneous_Wavenumber Analytic_Trace Instantaneous frequency measured in depth domain Integrated_Apparent_Seismic_Polarity Integrated_Trace The integral of the Apparent Polarity trace over a given interval Integrated_Cosine_Of_Phase Integrated_Trace The integral of the Cosine Of Phase trace over a given interval Integrated_Instantaneous_Frequency Integrated_Trace The integral of the Instantaneous Frequency trace over a given interval Integrated_Reflection_Strength Integrated_Trace The integral of the Reflection Strength trace over a given interval Integrated_Seismic_Amplitude Integrated_Trace The integral of the Seismic Amplitude trace over a given interval. Integrated_Seismic_Magnitude Integrated_Trace The integral of the absolute value of the Seismic Amplitude trace over a given interval. Integrated_Slowness Acoustic_Travel_Time Total acoustic travel time over a wellbore interval as computed by integrating acoustic slowness from a sonic log (Compressional_Slowness) over the interval. Integrated_Trace Amplitude The integral of an instantaneous attribute over a given interval. Inter_Bed_Contrast Conductivity_Contrast Conductivity ratio between adjacent beds Interfacial_Tension Data_Valued_Property The tension between two interfaces; e.g., light and heavy fluid phases, gas-liquid, gas-oil, gas-water. Also called surface tension or surface tensity Interfault_Angle Plane_Angle The smallest angle between two intersecting sealing faults in a wedge well test model. Intermediate Modifier Middle; being or occurring at the middle place or degree or between extremes. Intermediate_Time_Level Time_Interval Seismic line dependent adjustment to achieve a continuous, line independent reference surface International_Aircraft_Regulation Code International Aircraft Transportation Regulation pertaining to this type of Battery, e.g., IATA 3090 Cargo Only Internet_Address System_Identifier Address by which a particular computer system may be reached over the Internet. Interpolation_Method Method_Type Interpolation method used in the generation of data. Interporosity_Flow_Coefficient Indicator Describes the conductance of flow from matrix to fissures. Usually known as Lambda in reservoir dynamics. Interpretation_Grid_Count Count Number of Interpretation grids that exist for the horizon. Interpretation_Origin Source Specify where interpretation was performed on data. Interruption_Type Type The type of interruption in the Earth subsurface, e.g. Missing Section, Repeat Section, etc. Interval_Alkhalifah_Eta Alkhalifah_Eta Interval value of Alkhalifah's eta anisotropy parameter, describing the relationship between horizontal and moveout Compressional velocities, for each layer. Interval_Anisotropic_Axis_1_Crossline_Direction Anisotropic_Axis_1_Crossline_Direction Estimation of the anisotropic axis 1 crossline direction for a layer. Interval_Anisotropic_Axis_1_Inline_Direction Anisotropic_Axis_1_Inline_Direction Estimation of the anisotropic axis 1 inline direction for a layer. Interval_Anisotropic_Axis_2_Crossline_Direction Anisotropic_Axis_2_Crossline_Direction Estimation of the anisotropic axis 2 crossline direction for a layer. Interval_Anisotropic_Axis_2_Inline_Direction Anisotropic_Axis_2_Inline_Direction Estimation of the anisotropic axis 2 inline direction for a layer. Interval_Bale_Kappa Bale_Kappa Interval value of Bale's kappa, the mode-converted wave equivalent to eta, describing the relationship between horizontal and moveout Converted wave velocities, for each layer. Interval_Bale_Xi Bale_Xi Interval value of Bale's xi, the shear wave equivalent to eta, describing the relationship between horizontal and moveout shear wave velocities, for each layer. Interval_Compressional_Shear_Velocity_Ratio Compressional_Shear_Velocity_Ratio Value of compressional-shear velocity ratio in interval Interval_Crossline_Dip Crossline_Dip Estimation of the crossline dip for a layer. Interval_Density Density Interval value of the material density (density for a layer). Interval_Inline_Dip Inline_Dip Estimation of the inline dip for a layer. Interval_Length Length The length of an interval along a path, such as a Borehole path. Interval_Mode_Converted_Velocity Mode_Converted_Velocity Converted-wave velocity measured over a finite interval, with the interval usually determined by geologic layering. The converted wave velocity is determined from the time taken for the energy to travel in one direction as Compressional wave and in the other as Shear. Interval_Polarization_Azimuth Polarization_Azimuth Estimation of the polarization azimuth angle for a layer. Interval_Porosity Porosity Interval value of the material Porosity (Porosity for a layer). Interval_Q_Ratio Q_Ratio Interval value of the compressional wave quality factor. Interval_Qs_Ratio Qs_Ratio Interval value of the shear wave quality factor. Interval_Sayers_Anellipticity Sayers_Anellipticity Interval value of Sayers' normalized anellipticity factor an alternative to eta for describing the relationship between horizontal and moveout compressional velocities, for each layer. Interval_Schoenberg_Ellipticity Schoenberg_Ellipticity Interval value of Schoenberg's ellipticity factor, for each layer. Interval_Shear_Compressional_Velocity_Ratio Shear_Compressional_Velocity_Ratio Value of shear-compressional velocity ratio in interval Interval_Shear_Velocity Shear_Velocity Interval shear wave velocity, measured over a finite interval, with the interval usually determined by geologic layering. Interval_Thomsen_Delta Thomsen_Delta Interval value of Thomsen's delta anisotropy parameter, describing the relationship between vertical and moveout Compressional velocities, for each layer. Interval_Thomsen_Epsilon Thomsen_Epsilon Interval value of Thomsen's epsilon anisotropy parameter, describing the relationship between vertical and horizontal Compressional velocities, for each layer. Interval_Thomsen_Gamma Thomsen_Gamma Interval value of Thomsen's gamma anisotropy parameter, describing the relationship between Horizontally polarized Shear (SH) velocities in the vertical and horizontal directions, for each layer. Interval_Thomsen_Sigma Thomsen_Sigma Interval value of Thomsen's sigma anisotropy parameter, describing the relationship between Vertically polarized Shear (SV) velocities in the vertical direction and moveout SV velocity, for each layer. Interval_Time Time_Interval The time difference between two reflection events. It may vary due to velocity changes in different media, or changes in thickness of strata, or changes following erosion or structural deformation. Interval_Transit_Time Data_Valued_Property The travel time of a wave over a unit distance, hence the reciprocal of wave velocity. Interval_Velocity Avg_Acoustic_Velocity Average velocity in a layer or between two subsurface points; generally applied to a rock layer whose velocity can be considered homogeneous. May be derived from stacking velocity using the Dix equation (or a more refined variant). Interval_Velocity_Ellipticity_Azimuth Velocity_Ellipticity_Azimuth Estimation of the velocity ellipticity azimuth angle for a layer Interval_Velocity_Ellipticity_Flattening Velocity_Ellipticity_Flattening Estimation of the velocity ellipticity flattening for a layer. Interwell_Distance Reservoir_Distance Inter-well distance for a horizontal interference test Interwell_Storativity_Thickness Storativity_Thickness Inter-well Storativity-Thickness [phi*Ct*h] for a horizontal interference test. Intrinsic_Safety_Certification_Marking Annotation Mark made on an equipment item defining the type of intrinsic certification. Typical marking includes certifying authority symbol, type of protection, protection group for electrical apparatus and temperature class, e.g., "EEx ia I T5": CENELEC Intrinsic Safety-2 faults Methane 100 degree C. Intrinsic_Safety_Flag Flag When set, indicates that the equipment has been certified for use in a hazardous area. Equipment so certified has been examined by a National Certifying Authority and, where necessary, tested and found to comply with the requirement of a standard specification for the appropriate concept. Invasion_Annulus_Resistivity Resistivity Resistivity of the invasion annulus, a region of the formation lying between the flushed zone and the undisturbed formation, and filled with interstitial water displaced from the flushed zone.) Invasion_Diameter Diameter The diameter to which drilling mud filtrate has invaded porous and permeable rock around the borehole. Invasion_Radius Radius The radius of the "invaded zone", the region in which drilling mud filtrate has invaded porous and permeable rock around the borehole. Inverse_Flattening Shape Inverse of the flattening of an ellipse. Inverse_Penetration_Rate Data_Valued_Property Inverse of drilling penetration rate. Investigation_Radius Radius The radius of a circle (or cylinder) which has the primary influence on a measurement; material or objects outside the Investigation_Radius have little or no effect on the measurement. Investigation_Radius_Increase Length Increase of candidate borehole investigation radius Iron_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of iron to total dry weight Iron_Yield Elemental_Yield Elemental contribution of Iron with respect to total. Irreducible Modifier Impossible to bring into a desired, normal, or simpler state Irreducible_Water_Saturation Saturation The fraction of the pore volume occupied by water in a reservoir at maximum hydrocarbon saturation, such that it cannot be further reduced. Irreducible_Water_Volume_Fraction Water_Volume_Fraction The volume fraction of water which remains after flushing with hydrocarbon, with respect to the total volume. Isolated_Porosity_Volume_Fraction Volume_Fraction The volume fraction of isolated porosity with respect to the total volume. Issue_Number Identifier Issue (e.g. Volume,number) of a periodical publication Item_Code Code Code reference to an item. J_Function Function_Name Name of the J Function, a function used to normalize capillary pressure to account for differences in permeability, porosity, and fluid systems. J_Function_Coeff Coefficient Coefficients used in the J function, a function used to normalize capillary pressure to account for differences in permeability, porosity, and fluid systems. Jar_Operating_Time Operating_Time Operating time of the jar over the reporting period. Job_Count Count Number of jobs performed or included. Job_Number Identifier Reference number assigned to a job or service Joint_Count Count The number of joints of tubular goods. Journal_File File_Name File that maintains process history, i.e., the chain of actions performed on the object. KB_Receiver_Correction Correction Correction vector to receiver position relative to Kelly Bushing KB_Receiver_Dx X_Coordinate X coordinate of correction vector to receiver position relative to Kelly Bushing. KB_Receiver_Dy Y_Coordinate Y coordinate of correction vector to receiver position relative to Kelly Bushing. KB_Receiver_Dz Z_Coordinate Z coordinate of correction vector to receiver position relative to Kelly Bushing. KB_Source_Correction Correction Correction vector to source position relative to Kelly Bushing KB_Source_Dx X_Coordinate X coordinate of correction vector to source position relative to Kelly Bushing. KB_Source_Dy Y_Coordinate Y coordinate of correction vector to source position relative to Kelly Bushing. KB_Source_Dz Z_Coordinate Z coordinate of correction vector to source position relative to Kelly Bushing. Kaolinite_Volume_Fraction Volume_Fraction The volume fraction of kaolinite with respect to the total volume. Kick_Pressure Pressure Pressure measurement used for kick detection. Kick_Tolerance_Volume Volume Estimate of the volume of a kick (influx of fluid into the wellbore) at bottom hole conditions which can be shut in and circulated out without breaking the formation Kill_Line_Pressure Pressure Pressure observed at kill line/BOP. Kinematic_Viscosity Viscosity The dynamic viscosity of a fluid divided by the density of the fluid. Klinkenberg_Factor Coefficient Empirical conversion factor used to estimate Klinkenberg permeability from measured gas permeability. Klinkenberg_Permeability Absolute_Permeability Empirical permeability measure derived by extrapolating the trend of gas permeability versus inverse pressure to infinite pressure (zero inverse pressure). The result is equivalent to the permeability which would be measured if the sample were 100% saturated with a non-reactive liquid and is sometimes called "liquid permeability" and abbreviated KL (where L is a subscript). Kurtosis Statistical_Property A measure of the sharpness of a population distribution. If X10, X25, X75 and X90 are the values for which 10, 25, 75, and 90 percent of the population is smaller, respectively, then kurtosis = (X75 - X25) / 2(X90 - X10). LGS_Concentration Solids_Concentration Low gravity solid Concentration LGS_Removal_Efficiency Efficiency Ratio of the mass rate of LGS (low gravity solid) in the underflow of a piece of SCE (Solids Control Equipment) to the mass rate of LGS fed into it LOT_Equivalent_Mud_Weight Mud_Density Equivalent mud weight determined by the leak off test (LOT) for a new formation below last casing shoe via increasing the pressure until the formation starts taking fluid. LTLP_Filter_Cake_Thickness Filter_Cake_Thickness Thickness of filter cake produced under low temperature, low pressure (LTLP) conditions. LTLP_Filtrate_Volume Filtrate_Volume Volume of filtrate produced under low temperature, low pressure (LTLP) conditions. LWD_Operating_Time Operating_Time Operating time of the logging-while-drilling (LWD) equipment over the reporting period. LWD_Tool_Type Tool_Type The type of a tool used for Logging While Drilling. Lag_Usage_Flag Flag When set, wavelet lag is used. Landing_Collar_Depth Depth Measured depth of the collar on which the cement plugs seat : this data is required to compute the displacement volume of a cementing operation. Language Name Name of spoken or written language, such as English, Spanish, French, Mandarin, Russian, Chichimeq... Last_Calibration_Date Date Date when a sensor was last calibrated Last_Static_Pressure_Depth Depth Depth at which last reservoir pressure data were recorded Last_Static_Reservoir_Pressure Pressure Last reservoir pressure recorded Latent_Heat Heat The amount of thermal energy required to convert an unit mass of liquid at its boiling point to completely vapor. Latitude Plane_Angle The angle between the axis of the Earth and a tangent to the ellipsoid which approximates the shape of the Earth. Latitude_Longitude_Unit Unit_Code Unit for Latitude and Longitude data. Layer_Diffusivity Diffusivity Diffusivity (permeability divided by the product of porosity, fluid viscosity and fluid compressibility) for a reservoir layer. Layer_Storativity_Ratio Ratio Ratio of layer storativity to total storativity ("omegaj") Layer_Transmissibility_Ratio Ratio Ratio of layer transmissibility to total transmissibility ("kappaj") Lead_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of lead to total dry weight Lead_Yield Elemental_Yield Elemental contribution of Lead with respect to total. Leakoff_Height Height Portion of the zone fracturing fluids will leakoff into. It can be an aggregate of a number of geologic formations. Lease_Name Name Name of a lease Lease_Status Status Status of a lease. Lease_Suffix Name Suffix associated with lease (e.g., OCS-G) Left_Hidden_Width Width For core images, the width of the core which is hidden on the left side of the image (by core box, for example). Legal_Datum Geodetic_Datum_Code Code of legislated geodetic datum Legal_Description Description Legal description associated with a legal document or agreement, for instance, a description of the boundaries of a lease. Legal_Ellipsoid Ellipsoid_Code Code of legislated geodetic ellipsoid. Legal_Projection Projection_Code Code of legislated map projection method. Length Data_Valued_Property Linear extent of a measured distance or dimension. Length_Cocked Length Length of an equipment item such as a mechanical jar in cocked position Length_Compressed Length Length of an equipment item such as a mechanical jar in compressed position Length_Extended Length Length of an equipment item such as a mechanical jar in extended position Length_Recovered Length Length of a sample recovered from some well operation (e.g. Core Sample). Length_Uncertainty Uncertainty Uncertainty of a Length measurement. Length_Unit Unit_Code Unit for Length data Lessor_Bonus Money Bonus payed to lessor for signing Level_Count Count Number of levels in a sequence or portion of a sequence, such as in a hierarchy. Level_Number Ordinal_Number Identifier of a particular level in a sequence; used by GeoFrame as an auxiliary depth identifier. Library_Doc_File File_Name Name of file containing documentation for (software) library. Light_Phase_Flow_Velocity Flow_Velocity Flow velocity of light phase component of fluid. Lime_Concentration Chemical_Concentration Lime content in water based mud as determined per API RP13P Section 8 Line_Style Type Line drawing style, such as pattern of dots and dashes. Line_Thickness Type Line drawing width or thickness Line_Type Type The type of an Earth curvilinear object, e.g. the line along the intersection of 2 subsurface horizons. Linear_Thermal_Expansion Indicator The change in length of a material as a fraction of its total length due to a change in temperature at a constant pressure. Linear_Weight Weight Weight of an equipment item per unit length; e.g. Casing weight, pipe weight, cable weight, etc. Liquid_Flow_Velocity Flow_Velocity Flow velocity of liquid component of fluid. Liquid_Flowrate Flowrate Rate of flow of liquid. Liquid_Formation_Volume_Factor Formation_Volume_Factor Ratio of total liquid volume at specified (typically, reservoir) conditions to the total liquid volume at surface (stock tank) conditions. Liquid_Gas_Ratio Volume_Fraction Volume ratio of liquid (oil + water) to gas in a volume of fluid. Liquid_Head_Pressure Hydrostatic_Pressure Pressure, represented as the height of a column of dense fluid that can be supported by the pressure. Liquid_Radius Length Liquid radius in the Bowl = Bowl Inner Radius - Pond_Depth Liquid_Saturation Saturation The fraction of the total pore volume in a formation or rock sample occupied by liquid. Liquid_Viscosity Viscosity The viscosity of a liquid at specific temperature and pressure conditions. Litho_Density Bulk_Density Formation density as measured with a Litho-Density or Gamma-Gamma type logging tool; conventionally abbreviated RHOB. Litho_Description Description Textual description of the lithology. Litho_Gross_Thickness_Ratio Ratio Ratio of Litho_Thickness to Gross_Thickness of a reservoir summation interval. Litho_Penetration_Rate Data_Valued_Property The rate at which a drill bit penetrates a particular lithostratigraphic layer; measured in units of time per mass. Litho_Pressure Pressure The pressure produced by the weight of overlying rock. Also called Abnormal pressure. Litho_Thickness Thickness Total thickness for given lithology in a reservoir summation interval. Litho_Type Type The classification of lithology in a stratified environment, e.g. Carbonate, Shale, Sand, etc. Lithologic_Color Color The characteristic color of a lithologic sample. Live_Trace_Flag Flag Indicator if trace is live or dead. Load Force The load (down or up) exerted on some object; e.g., hook load. Load_Date Date Date data was loaded Loaded_By Person_Name Name of person who loaded data Local_Coord_Sys_Code Code Catalog Code of a locally defined coordinate system. Local_Coord_Sys_Name Name Name of a local coordinate system. Local_Paleo_Shoreline_Orient Orientation The orientation of a shoreline pertaining to the local paleontology. Location Data_Valued_Property The location of any Earth, Region, Equipment, or other entities relative to a coordinate system. Log_Flag Flag Flag indicating the presence of a log, or that an item or event is to be included in a log. Logger_Elevation_Reference_Code Code Code of the elevation reference for logging data Logger_Total_Depth Total_Depth The total depth of the well borehole as reported by the logging contractor. Logging_Cable_Flag Flag Y/N: tells if there is a wireline cable inside the tubing allowing logging Logging_Unit Serial_Number Serial number of the logging unit. Long_Term_Stability Data_Valued_Property Stability over the long term Longitude Plane_Angle Angle measured about the spheroid (or ellipsoid) axis from a local prime meridian to the meridian through the point. A positive value denotes East. Longitude_Reference_1 Longitude Latitude of first reference point in projection definition. Longitude_Reference_2 Longitude Latitude of second reference point in projection definition. Longitudinal_Amplitude Amplitude Amplitude of the longitudinal component in multi-component seismic. Longitudinal_Dispersivity_Coefficient Coefficient A coefficient used as a multiplier of interstitial velocity to estimate dispersion in the direction of movement for a displacement front in permeable media. Longitudinal_Relaxation_Time Relaxation_Time Longitudinal, or spin-lattice, relaxation time constant for alignment rate of nuclei to static magnetic field; normally abbreviated by symbol T1. Loss_On_Ignition Concentration Proportion by weight of a sample which remains after the sample has been heated (e.g. 1000 degC) in an oxygen atmosphere and the volatile oxides evaporated. Loss_On_Ignition_H2O_Plus Concentration Volatile Hydrogen component of Loss On Ignition, sometimes abbreviated H2O+. Lost_Time_Flag Flag Flag indicating whether or not an event caused a delay in operation. Low Modifier Of lesser degree, size, or amount than average or ordinary. Small in number or amount. Low_Power_Flag Flag Flag indicating whether or not the tool is operating in low power consumption mode. When the flag is set, the sensor warmup duration is taken into account. Lower_Fluid_Type Fluid_Type The type of fluid found in the layer below a reference surface (e.g. Water in layer below a Fluid Contact in a Reservoir.) Lower_Surface_Relation Type The type of relationship between a surface and the ones below (e.g. the surfaces below a Horizon are eroded). Luminous_Flux Data_Valued_Property Rate of flow of visible-wavelength radiant energy, as measured from a point source and within a unit solid angle. Luminous_Intensity Data_Valued_Property The density of luminous flux per unit solid angle, measured in a given direction relative to the emitting source. MRE_Latitude_Coefficient Coefficient Coefficient for a latitude term in a multiple regression equation for computing geodetic datum shifts. MRE_Longitude_Coefficient Coefficient Coefficient for a longitude term in a multiple regression equation for computing geodetic datum shifts. MSL_Receiver_Correction Correction Correction vector to receiver position relative to Mean Sea Level. MSL_Receiver_Dx X_Coordinate X coordinate of correction vector to receiver position relative to Mean Sea Level. MSL_Receiver_Dy Y_Coordinate Y coordinate of correction vector to receiver position relative to Mean Sea Level. MSL_Receiver_Dz Z_Coordinate Z coordinate of correction vector to receiver position relative to Mean Sea Level. MSL_Source_Correction Correction Correction vector to source position relative to Mean Sea Level. MSL_Source_Dx X_Coordinate X coordinate of correction vector to source position relative to Mean Sea Level. MSL_Source_Dy Y_Coordinate Y coordinate of correction vector to source position relative to Mean Sea Level. MSL_Source_Dz Z_Coordinate Z coordinate of correction vector to source position relative to Mean Sea Level. MWD_DPoint Data_Valued_Property Integer representation of MWD/LWD data as transmitted from the downhole tool. MWD_Data_Density Density Density of data samples per length of borehole traversed; may be expressed as samples per unit length or as a Boolean indicator of sample presence within a depth frame. MWD_Operating_Time Operating_Time Operating time of the MWD equipment over the reporting period. MWD_Tool_Code Code Specific code of a tool used for Measurement While Drilling. MWD_Tool_Type Tool_Type The type of a tool used for Measurement While Drilling. Magnesium_Concentration Chemical_Concentration Magnesium concentration in a material. Magnesium_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of magnesium to total dry weight Magnesium_Yield Elemental_Yield Elemental contribution of Magnesium with respect to total. Magnetic_Bladeface Bladeface In directional drilling, the angle between Magnetic North and a sensor contained in a stabilizer blade; Measurement represents an Azimuth, with values from 0 to 360 degrees. Magnetic_Declination Azimuth The horizontal angle measured from a meridian to the direction of magnetic north as determined by a freely suspended magnet. Positive if magnetic North is east of True North. Magnetic_Declination_Date Date Effective date and time at which the magnetic declination value has become valid. Magnetic_Declination_Source Source Name of a declination survey, a vendor of declination data, a reference book, or a person supplying the value. Magnetic_Field_Strength Data_Valued_Property The force per unit magnetic pole (or current per unit length). Also called Magnetizing Force or Magnetic Intensity. Magnetic_Flux Data_Valued_Property The flux through a surface is the integral over the surface of the normal component of the magnetic induction. Magnetic_Flux_Density Data_Valued_Property A vector quantity symbolized by B and given in terms of the force produced on a small element of length which is carrying an electric current. B relates to the magnetizing force by a constant called the Magnetic Permeability. Magnetic_Inclination Inclination The vertical angle measured between the horizontal plane and the direction of magnetic north as determined by a freely suspended magnet. Sometimes known as magnetic dip. Positive values if the direction to magnetic north is below the horizon. Magnetic_Permeability Data_Valued_Property The three-dimensional inductance of a material, a measure of the magnetic induction produced in a material by a given magnetic field strength. Free space (and nonmagnetic rock) has a permeability of 1.257*10-6 henrys/meter. Magnetic_Susceptibility Data_Valued_Property A measure of the degree to which a substance may be magnetized; the ratio of the magnetization to the magnetic field strength. Magnetic_Toolface Toolface In directional drilling, the angle between North and a reference direction on the drill string (e.g. Y-Axis accelerometer); used in hole sections of low deviation. Measurement represents an Azimuth, with values from 0 to 360 degrees. Magnetization Data_Valued_Property A measure of the effect of the medium on the magnetic field, B, when subject to a magnetizing force, H; B = Mu0 * (H + M), where Mu0 is the permeability of free space. Magnitude Data_Valued_Property Absolute value of Amplitude. Major_Axis Diameter Length of the major (long) axis of an ellipse. Major_Axis_Azimuth Azimuth Major axis Azimuth of the ellipse of uncertainty (related parameter: EOU_MAJOR_AXIS_AZIM) Major_Component Name The major component of a composition (e.g. the major component of a chemical product) Major_Dimension Length Major (normally longer) dimension of an object; the actual type of measurement depends upon the shape of the object. [Used for Drilling Targets, whose shapes could be Elliptical, Circular, Rectangular...] Mandatory Flag Flag indicating if a relationship is mandatory or optional for the referencing object. Manganese_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of manganese to total dry weight Manganese_Yield Elemental_Yield Elemental contribution of Manganese with respect to total. Manual_Control_Flag Flag Flag indicating whether the activity is/was controlled manually by the user (1) or automatically by the system or application (0) Manufacturer Organization_Code The unique code of the manufacturer, usually a company or organization code. Map_File File_Name Name of file containing standard map. Map_Migrated_Depth Depth Depth obtained through map migration of time surface data Map_Modeled_Time Two_Way_Time Two-way time obtained through map modeling of depth surface data Map_Scale Ratio The ratio of a distance measured on a map to the actual distance. It is normally expressed as a unitless ratio (e.g. 1:1000), or as the product of a unitless ratio and the ratio of two units (e.g. 1 in = 5 mile, or .2 in/mi). Map_Scale_Factor Scale_Factor The ratio of the scale along the meridian or along the parallel at a given point to the scale at some map point or along some line; each point on the map has a distinct value. Mass Data_Valued_Property The property of a body that is a measure of its inertia, that is commonly taken as a measure of the amount of material it contains, that causes a body to have weight in a gravitational field. Mass_Flowrate Data_Valued_Property A measure of flow rate expressed as mass of material per unit time. Mass_Fraction Ratio The ratio of the mass of a component to the total mass. Mass_Spectrum_Abundance Amount The abundances of the molecular constituents of a material; may be represented as voltage of a flame ionization detector, amount relative to a standard solution or actual mass quantities. Material_Addition_Count Count Number of packaging units of chemicals added to the drilling fluid. (e.g., Add 5 sacks of Barite C100 100lb/sack to the drilling fluid) Material_Addition_Depth_Increment Interval_Length The depth increment at which the material addition takes place (e.g., Add 5 sacks of Barite C100 100lb/sack to the drilling fluid each 500 ft) Material_Code Code Catalog code of material. Material_Phase Type The physical state or phase of a material, such as Liquid or Solid. Material_Type Type The type or class of materials both naturally occurring or used in some activity, e.g. Hydrocarbon, Mineral, Rock, Steel, Proppant, etc. Material_Weight Mass Weight of Material Matrix_Block_Skin Skin_Factor Matrix to natural fracture skin factor in a naturally fractured system. Matrix_Compressibility Compressibility The compressibility of a homogeneous solid material. Matrix_Compressional_Slowness Compressional_Slowness Acoustic slowness of a compressional wave in a given material or matrix. Matrix_Compressional_Velocity Compressional_Velocity Acoustic velocity of a compressional wave in a given material or matrix. Matrix_Electromagnetic_Propagation_Time Electromagnetic_Propagation_Time The time it takes for an electromagnetic wave to traverse a fixed distance of a given material or matrix. In this case the material or matrix is a specific, zero porosity rock, e.g. sandstone, limestone or dolomite. Matrix_Epithermal_Neutron_Porosity Epithermal_Neutron_Porosity Matrix response of an epithermal neutron porosity logging device. Matrix_Neutron_Capture_Cross_Section Neutron_Capture_Cross_Section The macroscopic capture cross section, i.e. the effective cross-sectional area per unit volume, of the rock matrix for the capture of neutrons. Matrix_Photoelectric_Factor Photoelectric_Factor Photoelectric Factor of the matrix (zero-porosity rock) or pure material; often expressed in an approximation unit barns/electron. Matrix_Shear_Slowness Shear_Slowness Acoustic slowness of a shear wave in a given material or matrix. Matrix_Shear_Velocity Shear_Velocity Acoustic velocity of a shear wave in a given material or matrix. Matrix_Specific_Gravity Specific_Gravity Specific gravity of the rock matrix. Typical value is 2.7 . Matrix_Thermal_Neutron_Porosity Thermal_Neutron_Porosity Matrix response of a thermal neutron porosity logging device. Matrix_Volume Volume The volume of material in a porous system that does not include the volume of the pores. Matrix_Volumetric_Photoelectric_Factor Volumetric_Photoelectric_Factor Matrix identification indicator computed from bulk density and Photoelectric Factor; often expressed in an approximation unit barns/cc. Max_Allowable_Flowrate Flowrate Maximum allowable flowrate for the equipment Max_Allowable_Pressure Pressure Maximum allowable pressure for the equipment Max_Allowable_Surface_Pressure Pressure Maximum allowable mud surface pressure in annulus (drill-pipe x casing) to be used during well control operations so as not to exceed the FIT/LOT equivalent mud weight. Max_Amount Amount Maximum Quantity Max_Amplitude Amplitude Maximum value of amplitude Max_Bend_1_Angle Bend_1_Angle Maximum first bent angle Max_Bend_2_Angle Bend_2_Angle Maximum second bent angle Max_Bend_Angle Plane_Angle Maximum bend angle range available, as in a bent sub. Max_Borehole_Diameter Borehole_Diameter Maximum borehole diameter Max_Calibrated_Value Multi_Use_Property Maximum value of the range for which the equipment is calibrated. Max_Casing_Inside_Diameter Inside_Diameter Maximum inside diameter of casing for which service or equipment is suitable Max_Concentration_1 Concentration_1 Maximum concentration or proportion of first component Max_Concentration_2 Concentration_2 Maximum concentration or proportion of second component Max_Concentration_3 Concentration_3 Maximum concentration or proportion of third component Max_Concentration_4 Concentration_4 Maximum concentration or proportion of fourth component Max_Data_Set_Count Count Maximum number of Data Set Max_Delay_Time Delay_Time Maximum Delay Time Max_Density Density Maximum density Max_Depth Depth Maximum Depth Max_Differential_Pressure Differential_Pressure Maximum Differential Pressure Max_Down_Load Load Maximum down load for an equipment item such as a drilling jar (lower limit of shock/cushion load.) Max_Element_Count Element_Count Maximum number of elements in a group or collection. Max_Extreme_Time Time_Interval Maximum time at extreme conditions Max_Flowrate Flowrate Maximum flowrate Max_Gamma_Ray Gamma_Ray Maximum value of Gamma Ray Max_Gas_Flowrate Gas_Flowrate Maximum gas flowrate Max_Gauge_Count Count Maximum number of Gauges possible with this type of Equipment Max_Gooseneck_Pressure Pressure Maximum pressure observed during a Coil Tubing job at the goose neck Max_Hole_Deviation Hole_Deviation Maximum deviation value of the wellbore from the vertical Max_Hydraulic_Power Hydraulic_Power Maximum hydraulic power (Flowrate x pressure) of a fluid. Often referred to Hydraulic horse power Max_Inclination Inclination Maximum inclination of sensor Max_Index Multi_Use_Property Generalized maximum value of index, typically distance or time. Max_Lift_Load Load Maximum lift load Max_Magnitude Magnitude Maximum magnitude. Max_Manifold_Choke_Size Inside_Diameter Maximum inner diameter of the choke orifice Max_Mud_Density Mud_Density Maximum allowable mud density Max_Oil_Flowrate Oil_Flowrate Maximum oil flowrate Max_Operating_Pressure Pressure Maximum pressure which an equipment can withstand without permanent damage at standard temperature. Max_Operating_Temperature Temperature Maximum operating temperature for an equipment item. Max_Outer_Vessel_Pressure Pressure Maximum working pressure of the outer equipment Max_Outside_Diameter Outside_Diameter Maximum outside diameter of an equipment item. Max_Pressure Pressure Maximum pressure Max_Rig_Heave Rig_Heave Maximum amplitude of the vertical motion of the rig Max_Sequence_Count Count Maximum Sequence Count Max_Shale_Volume_Fraction Volume_Fraction Maximum value of Shale/Clay volume fraction Max_Storage_Temperature Temperature Maximum Storage Temperature Max_Surge_Pressure Pressure Maximum pressure to which this Equipment can be exposed for a short time without permanent damage; the Equipment will again perform to specifications when the pressure is reduced below the maximum working pressure. Max_Surge_Temperature Temperature Maximum Temperature to which this Equipment can be exposed for a short time without permanent damage; the Equipment will again perform to specifications when the Temperature is reduced below the maximum working temperature. Max_Temperature Temperature Maximum temperature Max_Temperature_Reached Temperature Maximum temperature reached by the system, sensor or equipment Max_Tension Tension Maximum tension Max_Thickness Thickness Maximum thickness, as for a reservoir unit. Max_Threshold Threshold Maximum threshold value. Max_Tool_Speed Tool_Speed Maximum service speed allowed for, or attained by, a logging tool. Max_Up_Pull Force Maximum up pull for an equipment item, such as drilling jars (upper limit of shock/cushion load). Max_Voltage Electric_Potential Maximum Voltage Max_Volume Volume The maximum volume not to be exceeded for a container (Tank, Mud Pit) Max_Water_Flowrate Water_Flowrate Maximum water flowrate Max_Water_Pressure Pressure Maximum water pressure Max_Water_Saturation Water_Saturation Maximum value of Water Saturation Max_Weight_On_Bit Weight_On_Bit Maximum weight on bit Max_Working_Pressure Working_Pressure Recommended maximum pressure at which equipment can be used Max_Working_Temperature Working_Temperature Recommended maximum temperature at which equipment can be used Max_X X_Coordinate Maximum X Coordinate for region Max_Y Y_Coordinate Maximum Y Coordinate for region Maximum Modifier The greatest quantity or value attainable or attained. An upper limit allowed by authority. The largest of a set of numbers. Mean_Particle_Diameter Diameter Average diameter of the particle (e.g. for Gravel pack sand 20/40 mean diameter=0 .025 inc/0.635 mm, 40/60 mean diameter=0.014 inch/0.355mm). Measure_Point_Offset Length Distance from the Measure Point to the Reference Plane for the assembly or tool; a positive value indicates that the Measure Point is above the Reference Plane. Measure_Reference_Plane_Offset Length Distance from the Measure Reference Plane to the bottom of the Equipment (which is for a tool practically the make-up line of the bottom connection). The Measure Reference Plane allows recording of the location of the sensor measure point in an equipment composition. The measure point is positioned by a length called Measure_Point_Offset, a property of the composition to which the sensor belongs. The Measure_Point_Offset is the distance from the measure reference plane of the part, i.e., sensor or tool, to the measure reference plane of the whole, i.e., tool or tool string. Measured Modifier Metrical. Estimated or appraised by a criterion. Measured_Depth Depth Depth measured along the borehole path from the working datum. Mechanical_Skin Skin_Factor Sum of Completion_Skin, Formation_Damage_Skin including anything limiting the flow across the completed interval. Does not include Partial_Completion_Skin. Median Modifier Being in the middle or in an intermediate position. Medium_Conductivity Conductivity The conductivity which represents a measurement made approximately two to three feet into the formation; generally considered to measure the formation where it contain fluids which are a mixture of mud filtrate, connate water and possibly hydrocarbons. Medium_Induction_Conductivity Medium_Conductivity The conductivity, made by an induction log, which represents a measurement made approximately two to three feet into the formation. Medium_Induction_Resistivity Medium_Resistivity The resistivity, made by an induction log, which represents a measurement made approximately two to three feet into the formation. Medium_Lateral_Resistivity Medium_Resistivity Resistivity measurement using a "lateral" electrode arrangement with a "medium" investigation radius (~a foot or two into the formation). Medium_Laterolog_Conductivity Medium_Conductivity The conductivity, measured by a laterolog (or guard log) resistivity device, which represents a measurement made approximately two to three feet into the formation. Medium_Laterolog_Resistivity Medium_Resistivity The resistivity, measured by a laterolog (or guard log) resistivity device, which represents a measurement made approximately two to three feet into the formation. Medium_Resistivity Resistivity The resistivity which represents a measurement made approximately two to three feet into the formation; generally considered to measure the formation where it contain fluids which are a mixture of mud filtrate, connate water and possibly hydrocarbons. Memory_Guard_Flag Flag Flag indicating whether or not a memory guard (memory saving mechanism which decreases the acquisition rate above 80% memory usage) option was selected. Memory_Size Data_Valued_Property Memory Size, generally expressed in kilobytes or Megabytes Memory_Type Type Memory Type, e.g., EEPROM, RAM ... Memory_Usage Ratio Ratio of memory used to total memory. Mercury_Saturation Saturation The fraction of the total pore volume in a rock sample occupied by mercury (special core analysis) Merge_Strategy Type Strategy for merging data, such as into a waveform gather. Metamorphic_Volume_Fraction Volume_Fraction The volume fraction of metamorphic rock with respect to the total volume. Method Name Name of method used, such as in acquiring or processing data. Method_Type Type The type of method used in an analysis activity in the lab or other type of activities at the wellsite. For example: chemical treatment methods. Mf_Titration_Volume Volume Amount of 0.02 normal (N/50) standard sulfuric acid required in order to turn the color of methyl orange indicator solution from yellow to pink when determining methyl orange alkalinity of the mud filtrate, Mf, API RP13 Section 8, Chemical Analysis. Micro_Conductivity Conductivity A measurement of the conductivity of the formation within the first few inches of the borehole wall. Micro_Cylindrically_Focused_Resistivity Micro_Resistivity A measurement of the resistivity of the formation, by a cylindrically focused tool, within the first few inches of the borehole wall. Micro_Inverse_Resistivity Micro_Resistivity Micro Resistivity measurement using an "inverse" lateral electrode arrangement; traditionally combined with Micro Normal Resistivity in a Microlog survey for identifying permeable beds. Micro_Lateral_Resistivity Micro_Resistivity Resistivity measurement using a "lateral" electrode arrangement with a very shallow investigation radius (1-2 inches into the formation). Micro_Laterolog_Conductivity Micro_Conductivity A measurement of the conductivity of the formation, by a laterolog (or guard log) resistivity device, within the first few inches of the borehole wall. Micro_Laterolog_Resistivity Micro_Resistivity A measurement of the resistivity of the formation, by a laterolog (or guard log) resistivity device, within the first few inches of the borehole wall. Micro_Normal_Resistivity Micro_Resistivity Micro Resistivity measurement using a "normal" electrode arrangement; traditionally combined with Micro Inverse Resistivity in a Microlog survey for identifying permeable beds. Micro_Resistivity Resistivity A measurement of the resistivity of the formation within the first few inches of the borehole wall. Micro_Spherically_Focused_Conductivity Micro_Conductivity A measurement of the conductivity of the formation, by a spherically focused tool, within the first few inches of the borehole wall. Micro_Spherically_Focused_Resistivity Micro_Resistivity A measurement of the resistivity of the formation, by a spherically focused tool, within the first few inches of the borehole wall. Migrated_Time_Interpretation Time_Interpretation Seismic travel time interpretation based on migrated sections; typically represented as a grid. Migration_Velocity Acoustic_Velocity Velocity applied in seismic migration. Min_Allowable_Flowrate Flowrate Minimum allowable flowrate for the equipment Min_Amount Amount Minimum quantity, number of items. Min_Amplitude Amplitude Trace min amplitude Min_Borehole_Diameter Borehole_Diameter Minimum borehole diameter Min_Calibrated_Value Multi_Use_Property Minimum value of the range for which the equipment is calibrated. Min_Casing_Inside_Diameter Inside_Diameter Minimum inside diameter of casing for which service or equipment is suitable Min_Compress_Outside_Diameter Outside_Diameter Minimum compressed outside diameter, such as for a centralizer. Min_Concentration_1 Concentration_1 Minimum concentration or proportion of first component Min_Concentration_2 Concentration_2 Minimum concentration or proportion of second component Min_Concentration_3 Concentration_3 Minimum concentration or proportion of third component Min_Concentration_4 Concentration_4 Minimum concentration or proportion of fourth component Min_Delay_Time Delay_Time Minimum Delay Time Min_Density Density Minimum density Min_Depth Depth Minimum Depth of Activity Min_Element_Count Element_Count Minimum number of elements in a group or collection. Min_Flowrate Flowrate Minimum flowrate Min_Gas_Flowrate Gas_Flowrate Minimum gas flowrate Min_In_Situ_Stress Stress Formation minimum principal stress, the smallest of the 3 components of the diagonal stress tensor (fractures will propagate perpendicular to its direction). Can be defaulted to Frac Gradient x TVD. Can be output from DataFRAC treatment. Min_Index Multi_Use_Property Generalized minimum value of index, typically distance or time. Min_Inside_Diameter Inside_Diameter Minimum inside diameter of an equipment item. Min_Magnitude Magnitude Minimum magnitude Min_Net_Thickness Thickness It is common in an interbedded reservoir for sands thinner than a certain cutoff thickness (Min_Net_Thickness) to be discarded as non net or non pay in a ResSum type analysis. However, a thick sand may have two closely spaced shale stringers, such that they create the effect of a thin sand separated from thick sands above and below by thin shale beds. In this case, if the shale beds are thinner than a second thickness threshold (Min_Non_Net_Thickness), the thin sand would be counted as net or pay. Min_Non_Net_Thickness Thickness It is common in an interbedded reservoir for sands thinner than a certain cutoff thickness (Min_Net_Thickness) to be discarded as non net or non pay in a ResSum type analysis. However, a thick sand may have two closely spaced shale stringers, such that they create the effect of a thin sand separated from thick sands above and below by thin shale beds. In this case, if the shale beds are thinner than a second thickness threshold (Min_Non_Net_Thickness), the thin sand would be counted as net or pay. Min_Oil_Flowrate Oil_Flowrate Minimum oil flowrate Min_Oil_Saturation_3Phase Oil_Saturation Minimum oil saturation in a 3 phase system. (SCAL SORM) Min_Outside_Diameter Outside_Diameter Minimum outside diameter of an equipment item. Min_Permeability Permeability Minimum value of Permeability Min_Porosity Porosity Minimum value for Porosity Min_Scan_Time Time_Interval Scan Time corresponding to the fastest scanning rate supported by the Equipment Min_Storage_Temperature Temperature Minimum Storage Temperature Min_Thickness Thickness Minimum thickness, as for a reservoir unit. Also used for stress calculation with coiled tubing, with data supplied by the manufacturer Min_Threshold Threshold Minimum threshold value. Min_Voltage Electric_Potential Minimum Voltage Min_Water_Flowrate Water_Flowrate Minimum water flowrate Min_Working_Temperature Working_Temperature Recommended minimum temperature at which equipment can be used Min_X X_Coordinate Minimum X Coordinate for region Min_Y Y_Coordinate Minimum Y Coordinate for region Mineral_Class Type The classification of a mineral. Mineral_Code Code Catalog-controlled code of a mineral. Mineral_Concentration Volume_Fraction Volume of a particular mineral per unit volume of the investigated material, such as a sample. Mineral_Conductivity Conductivity Mineral Conductivity Mineral_Density Density The density of a mineral. Mineral_Group Type The group to which a mineral belongs. Mineral_Hardness Data_Valued_Property The hardness of a rock sample expressed in units of the MOH reference standard. Mineral_Number Ordinal_Number Index in the cumulative mineral array which are naturally indexed and not indexed by Zone_Number. Mineral_Resistivity Resistivity Mineral Resistivity Minimum Modifier The least quantity assignable, admissible, or possible. The least of a set of numbers Minor_Axis Diameter Length of the minor (short) axis of an ellipse. Minor_Dimension Length Minor (normally shorter) dimension of an object; the actual type of measurement depends upon the shape of the object. [Used for Drilling Targets, whose shapes could be Elliptical, Circular, Rectangular...] Minus_Tolerance Tolerance Amount of negative tolerance on a measurement value; the unit quantity is determined by that of data value. Mis_Tie_Phase_Correction Phase_Shift Phase correction to apply to line to compensate for differences in Tie_Point_Phase_Shift Mis_Tie_Phase_Time_Equivalent Time_Interval Equivalent time correction corresponding to the phase corrections. Assumes a specified dominant frequency. Mis_Tie_Static_Time_Correction Time_Interval Constant time correction to apply to a seismic line to compensate for time differences. Mis_Tie_Variable_Time_Correction Time_Interval Time correction applicable to each trace on a seismic line. Mixing_Order Ordinal_Number Order in which the materials are added together. This order matters e.g. the acid is poured into the water and not the contrary, the water to the flour ... Mixture_Type Type Qualifier to determine if a component is a pure chemical or a mixture of other chemicals. Mobility Data_Valued_Property The measure of the ease with which a fluid can be moved in a specific medium (i.e. rock). The ratio of the effective permeability and the viscosity of the fluid. Mobility_Ratio Ratio Ratio of the mobility of one system or layer (permeability divided by viscosity) to that of another system or layer. Mode_Converted_Velocity Acoustic_Velocity Converted-wave velocity corresponding to a Compressional wave traveling in one direction and a Shear wave traveling the opposite direction, with conversion at the reflector. Model_Fit_Error Statistical_Property Generic property for a measure of how well the actual data fit a model of the expected values and/or distribution of data. Standard measures include Standard Deviation, Variance, Chi-Square. Model_Input_Measurement Unit_Quantity_Code Input measurement (Unit Quantity) for a calibration or computation model Model_Input_Unit Unit_Code Input unit for a calibration or computation model Model_Name Name Name of a model or version of some entity; for equipment, it may coincide with the trade name. Model_Output_Measurement Unit_Quantity_Code Output Measurement (Unit Quantity) for a calibration or computation model Model_Output_Unit Unit_Code Output unit for a calibration or computation model Model_Year Date The year or full date of a model usually of an equipment item. Modified_By Person_Name Name of person who modified data Modifier Property A modifier is a property that is used to qualify another property (data or relation valued); e.g., Calibrated, Corrected, Computed, Average, etc. Modify_Date Date Date of modification of a data item in the database. Module_State Status Indicates the execution status of a module, such as Running, Aborted, etc. Module_Weight Weight Module Weight Molar_Concentration Concentration The ratio of the number of moles of a material in a sample to the volume of the sample. Mole_Fraction Concentration The ratio of the number of moles of a component to the total number of moles present. Molecular_Weight Data_Valued_Property Ratio of the mass of a molecule of a substance to 1/12 of the mass of a Carbon12 atom; calculated as the sum of the atomic weights of the constituent atoms. Money Data_Valued_Property Amount of money; should be associated with a unit of currency. Monophasic_Fluid_Flag Flag Indicates if the fluid is monophasic Monotonic_Flag Flag Flag indicating that the data increase or decrease monotonically along their index. A monotonic function is one whose value either never increases or never decreases as the independent variable increases. Montmorillonite_Volume_Fraction Volume_Fraction The volume fraction of illite with respect to the total volume. Morpho_Type Type The classification of rocks from their internal morphology i.e., lamination thickness, inclusion size, etc. Motor_Operating_Time Operating_Time Operating time of the motor over the reporting period. Motor_Speed Angular_Velocity The rotational speed of a motor. Moved_Hydrocarbon_Volume_Fraction Hydrocarbon_Volume_Fraction The volume fraction of moved hydrocarbons with respect to the total volume; moved hydrocarbons are those which have been displaced from the flushed zone by the invasion process. Mud_Background_Gas_Factor Gas_Fraction Drill fluid background gas content as output by the chromatograph in circulating conditions. Mud_Chloride_Concentration Concentration Concentration of chlorides in mud. Mud_Compressional_Slowness Fluid_Compressional_Slowness Acoustic compressional slowness (Delta-T) of the drilling fluid. Mud_Connection_Gas_Factor Gas_Fraction Drill fluid gas content spike as output by the chromatograph after stopping circulation in order to make or break connections. Mud_Density Density The density of mud, or drilling fluid, used during drilling operations. Mud_Filtrate_Methyl_Orange_Alkalinity_Mf Alkalinity The volume ratio of 0.02 normal (N/50) standard sulfuric acid (Mf_Titration_Volume) including that amount required for the Pf endpoint (Pf_Titration_Volume) to mud filtrate, API RP13 Section 8, Chemical Analysis. Mud_Filtrate_Phenolphthalein_Alkalinity_Pf Alkalinity The volume ratio of 0.02 normal (N/50) standard sulfuric acid (Pf_Titration_Volume) to mud filtrate volume, API RP13 Section 8, Chemical Analysis. Mud_Filtrate_Resistivity Resistivity Resistivity of Mud Filtrate Mud_Filtrate_Volume_Per_Length Volume_Per_Length The measure of volume of mud filtrate lost to the formation per linear length of borehole, usually given in U.S. gal/ft. Mud_Flowrate Flowrate The rate at which mud, or drilling fluid, is being pumped into, or output from, a borehole or some storage unit. Mud_Nitrate_Concentration Concentration Concentration of nitrates in mud. Mud_Phenolphthalein_Alkalinity_Pm Alkalinity The volume ratio of 0.02 normal (N/50) standard sulfuric acid (Pm_Titration_Volume) to mud volume in API Mud Phenolphthalein Alkalinity test (API RP13 Section 8, Chemical Analysis). Mud_Pressure_Gradient Pressure_Gradient The Mud density expressed in pressure gradient. Usually used to compare the mud induced pressure with the pore and frac pressure. Mud_Pump_Discharge_Pressure Pressure Mud pump maximum discharge pressure Mud_Pump_Monitoring_Purpose Type The purpose of the mud pump monitoring. It can be either for well control or monitoring the pump parameters at working conditions. Mud_Pump_Output Mud_Flowrate Mud pump maximum output, measured in terms of the rate of amount or mud output. Mud_Pump_Power Hydraulic_Power Mud pump input horse power. Mud_Pump_Type Type The type of pump used to pump drilling fluid or mud, usually into the borehole during drilling operations. Mud_Resistivity Resistivity Resistivity of Drilling Fluid, also known as mud. Mud_Temperature Fluid_Temperature The temperature of a mud or drilling fluid (sample) under certain conditions. Mud_Trip_Gas_Factor Gas_Fraction Bottom hole drill fluid gas content spike as output by the chromatograph after stopping circulation for a significant time interval such as when tripping into the hole. Mud_Type Type Type of mud used Mudcake_Membrane_Stiffness Data_Valued_Property Characterization of the flexibility of mudcake, defined as the ratio of the stress difference across the mudcake-formation boundary to the relative displacement between the pore fluid and the solid frame. Multi_Comp_Compressional_Angle Plane_Angle The angle between the vector perpendicular to the wave front, and the amplitude vector of the seismic defined by the X,Y and Z components. Seabed compressional velocity used. Multi_Comp_Magnitude Magnitude Magnitude of multi component seismic Multi_Comp_Shear_Angle Plane_Angle The angle between the vector perpendicular to the wave front and the amplitude vector of the seismic defined by the X,Y and Z components. Seabed shear velocity used. Multi_Intersection_Flag Flag Flag to indicate that two geometric objects have more than one intersection; for example a wellbore may intersect a geologic feature more than once, due to the geometry of the wellbore path or that of the geologic feature. Multi_Use_Property Data_Valued_Property Property whose meaning can only be interpreted within the context of its use; for example, the meaning of Max_Value requires a context to determine a type of measurement. Multi_Valued_Flag Flag Boolean indicating if the Horizon has multiple Z values for a single X,Y location. Muscovite_Volume_Fraction Volume_Fraction The volume fraction of muscovite with respect to the total volume. Mute_Taper_Length Element_Count Number of samples muted in the traces N2_Concentration Chemical_Concentration Concentration of Nitrogen N2_Foam_Quality Ratio Ratio volume of N2 over foam volume . Indicator of the quality of a foam generated with N2 for well treatment. Below 50% the foam is not stable, above 95% the foam changes to a mist. NMR_Amplitude_Distribution Data_Valued_Property Distribution of nuclear magnetic resonance amplitudes for different values of transverse relaxation time (T2); normally represented as a waveform of amplitude values indexed by T2 components. NMR_Diffusion_Coefficient Data_Valued_Property In nuclear magnetic resonance analysis, the measure of the ability of the molecule containing the polarized proton to diffuse (or move) through a medium. NMR_Fitting_Error Error Error in NMR window sum or raw echo fitting. NMR_Permeability Permeability Formation permeability as measured with an nuclear magnetic logging device. NMR_Porosity Apparent_Porosity Apparent formation porosity as measured with an nuclear magnetic logging device. NMR_Quality_Indicator Quality_Indicator Property used to indicate quality or confidence of data from a nuclear magnetic resonance logging device. NMR_T2_Distribution Volume_Fraction Distribution of volume fractions for different values of transverse relaxation time (T2); normally represented as a waveform of volume fraction values indexed by T2 components. NRM_Factor Coefficient NRM factor Name Data_Valued_Property The name given to any object or data item, e.g. Name of Well, Name of Field, etc. Namespace_Code Code Code of a Namespace across which object names are unique. Naming_System Type Name of the system which controls the valid or legal names of entities. For example, there are numerous system for naming wells: API 12 digit, CPA, Tobin Nascent Modifier The most primitive data recovered in the data acquisition process. Such data and their indices are usually unscaled and are thus only usable by dedicated acquisition processing software. Negative Modifier Less than zero and opposite in sign to a positive number that when added to the given number yields zero. Negative_Slope Multi_Use_Property Negative slope value. Negative_Threshold Threshold Negative threshold value. Neighborhood Type A topological property indicating whether a spatial object lies to the "left" or to the "right" of a neighboring object whose orientation sense has been specified. Net Modifier Excluding all tare. Final. Net_Cutoff_Absent_Fraction Quality_Indicator Fraction of the summation interval for which data to apply "Net" cutoff criteria are unavailable; used as a coarse indicator of the reliability of the summation results. Net_Fracturing_Pressure Pressure Hydraulic pressure exerted on a formation during a fracturing job (fracture pressure) minus Closure Pressure. Net_Gross_Thickness_Ratio Ratio Ratio of Net_Thickness to Gross_Thickness Net_Load Load Weight Indicator load minus any extra equipment weight (Injector head, Hook...) Net_Pay_Clay_Volume_Fraction Clay_Volume_Fraction Average clay volume fraction in the net pay portion of the zone interval (thickness weighted arithmetic average). Net_Pay_Cutoff_Absent_Fraction Quality_Indicator Fraction of the summation interval for which data to apply "Net_Pay" cutoff criteria are unavailable (including the fraction for which "Net" or "Net_Reservoir" criteria are unavailable); used as a coarse indicator of the reliability of the summation results. Net_Pay_Flushed_Zone_Water_Saturation Flushed_Zone_Water_Saturation Average flushed zone water saturation in the net pay portion of the zone (thickness weighted arithmetic average). Net_Pay_Gross_Thickness_Ratio Ratio Ratio of Net_Pay_Thickness to Gross_Thickness Net_Pay_HC_Porosity_Thickness Thickness Total Net Pay hydrocarbon porosity-thickness for all zones; that portion of Net_Pay_Porosity_Thickness which is hydrocarbon-filled. Net_Pay_Moved_HC_Porosity_Thickness Thickness The net pay moved hydrocarbon volume multiplied by the net pay thickness; the portion of Net Pay Porosity Thickness filled with moved hydrocarbons. Net_Pay_Moved_HC_Volume_Fraction Moved_Hydrocarbon_Volume_Fraction Net pay moved hydrocarbon volume fraction: moved oil saturation (Sxo-Sw) in the net pay of the zone multiplied by the net pay average porosity. Net_Pay_Permeability Permeability Average permeability in the net pay portion of the zone interval (thickness weighted arithmetic average). Net_Pay_Permeability_Thickness Permeability_Thickness Thickness of the permeable net pay portion of the zone i.e., the product of the Net Pay Thickness and Net Pay Average Permeability Net_Pay_Porosity Porosity Average Porosity of the levels which satisfy "pay zone" criteria; such criteria typically include cutoffs for clay content, porosity, water saturation and permeability. Net_Pay_Porosity_Thickness Thickness Total net pay porosity-thickness of the zone interval: the product of Net Pay Thickness and Net Pay Average Porosity Net_Pay_Thickness Thickness The cumulative thickness of hydrocarbon bearing rocks which satisfy local criteria for a "pay zone"; the footage which satisfies the Net Reservoir conditions and where the water saturation cutoff, permeability cutoff and any discriminator cutoffs specified as "Net Pay" are satisfied; abbreviated "H" for a Hydraulic Unit. Net_Pay_Water_Saturation Water_Saturation Average water saturation in the net pay portion of the zone (thickness weighted arithmetic average). Net_Reservoir_Clay_Volume_Fraction Clay_Volume_Fraction Average volume fraction of clay in the Net Reservoir portion of the zone (thickness weighted arithmetic average). Net_Reservoir_Core_Grain_Density_Point_Match Grain_Density Average grain density in the Net Reservoir portion of the summation interval, computed from core data by point-match method. Net_Reservoir_Core_Permeability_Point_Match Permeability Average permeability in the Net Reservoir portion of the summation interval, computed from core data by point-match method. Net_Reservoir_Core_Porosity_Point_Match Porosity Average porosity in the Net Reservoir portion of the summation interval, computed from core data by point-match method. Net_Reservoir_Core_Water_Saturation_Point_Match Water_Saturation Average water saturation in the Net Reservoir portion of the summation interval, computed from core data by point-match method. Net_Reservoir_Cutoff_Absent_Fraction Quality_Indicator Fraction of the summation interval for which data to apply "Net_Reservoir" cutoff criteria are unavailable (including the fraction for which "Net" criteria are unavailable); used as a coarse indicator of the reliability of the summation results. Net_Reservoir_Flushed_Zone_Water_Saturation Flushed_Zone_Water_Saturation Average flushed zone water saturation in the net reservoir portion of the zone (thickness weighted arithmetic average). Net_Reservoir_Gross_Thickness_Ratio Ratio Ratio of Net_Reservoir_Thickness to Gross_Thickness Net_Reservoir_HC_Porosity_Thickness Thickness Total Net Reservoir hydrocarbon porosity-thickness for all zones; that portion of Net_Reservoir_Porosity_Thickness which is hydrocarbon-filled. Net_Reservoir_Log_Grain_Density_Point_Match Grain_Density Average grain density in the Net Reservoir portion of the summation interval, computed from log data by point-match method. Net_Reservoir_Log_Permeability_Point_Match Permeability Average permeability in the Net Reservoir portion of the summation interval, computed from log data by point-match method. Net_Reservoir_Log_Porosity_Point_Match Porosity Average porosity in the Net Reservoir portion of the summation interval, computed from log data by point-match method. Net_Reservoir_Log_Water_Saturation_Point_Match Water_Saturation Average water saturation in the Net Reservoir portion of the summation interval, computed from log data by point-match method. Net_Reservoir_Permeability Permeability Average permeability in the net reservoir portion of the zone interval (thickness weighted arithmetic/geometric/harmonic average). Net_Reservoir_Permeability_Thickness Permeability_Thickness The product of the Net Reservoir Thickness and Net Reservoir Average Permeability. Net_Reservoir_Porosity Porosity Average porosity in the Net Reservoir portion of the zone (thickness weighted arithmetic average). Net_Reservoir_Porosity_Thickness Thickness Total pore thickness of the zone; i.e. the product of Porosity and Net_Reservoir_Thickness. Net_Reservoir_Thickness Thickness Total thickness of the portion of the zone which has porosity suitable to be a potential reservoir; i.e. the footage which satisfies the Net Thickness conditions and where the porosity cutoff and any discriminator cutoffs specified as "Net Reservoir" are satisfied. Net_Reservoir_Water_Saturation Water_Saturation Average water saturation in the net reservoir portion of the zone (thickness weighted arithmetic average). Net_Shale_Thickness Thickness Difference between Gross_Thickness and Net_Thickness; i.e. the thickness of the formations excluded from "Net" due to cutoff for maximum clay content. Net_Thickness Thickness Total thickness of the non-shales in the interval; i.e. total footage where the clay volume cutoff and any discriminator cutoffs specified as Net are satisfied. Neutron_Capture_Cross_Section Data_Valued_Property The effective area within which a neutron passes in order to be captured by an atomic nucleus. Commonly called Sigma. Neutron_Capture_Cross_Section_Quality_Indicator Quality_Indicator Property used to indicate quality or confidence of data from a neutron capture cross section survey. Neutron_Data_Density MWD_Data_Density Density of data samples per length of borehole traversed, for a neutron logging measurement. Neutron_Diffusion_Length Length Average straight-line distance a neutron travels at thermal energy levels before being absorbed by a formation nucleus. Neutron_Porosity Apparent_Porosity Porosity as measured with an neutron logging device. Neutron_Porosity_Dolomite Neutron_Porosity Porosity derived from a neutron logging measurement, assuming that the rock matrix material is dolomite. Neutron_Porosity_Limestone Neutron_Porosity Porosity derived from a neutron logging measurement, assuming that the rock matrix material is calcite. Neutron_Porosity_Sandstone Neutron_Porosity Porosity derived from a neutron logging measurement, assuming that the rock matrix material is quartz. Neutron_Quality_Indicator Quality_Indicator Property used to indicate quality or confidence of data from a neutron survey. Neutron_Slowing_Down_Length Length Average straight-line distance a neutron travels in being slowed from natural source energy to epithermal energy levels by collisions with formation nuclei. Neutron_Time_After_Bit Time_After_Bit In MWD/LWD logging, the time delay between the drill bit and a neutron sensor reaching a given point in the wellbore. Newtonian_Viscosity Viscosity Slope of Shear Stress/Shear Rate curve for the Newtonian rheology model (Shear Stress proportional to Shear Rate) Next_Receiver_Group_Distance Length For non-equidistant receiver groups, distance to next group Nickel_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of nickel to total dry weight Nickel_Yield Elemental_Yield Elemental contribution of Nickel with respect to total. Nitrogen_Mole_Fraction Mole_Fraction Mole fraction of Nitrogen to total gas composition Nitrogen_Yield Elemental_Yield Elemental contribution of Nitrogen with respect to total. Node_Locked_Flag Processing_Option A Y/N flag indicating whether a particular Node is locked and cannot be displaced. Node_Type Type The type of (topological) Node, as used in the Region submodel. Noise_Amplitude Amplitude The amplitude of noise or unwanted portion of a signal. Noise_Coefficient Coefficient Noise coefficient of pressure sensor Noise_To_Signal_Ratio Ratio The ratio of noise amplitude to signal amplitude, usually expressed in dB. Note: the inverse, Signal_To_Noise_Ratio, is preferred and should be used whenever possible. Nom_Borehole_Diameter Borehole_Diameter Nominal inside diameter of a borehole; often referred to a "bit size". Nom_Cable_Depth Depth Nominal cable depth, such as that planned for the receiver cable in a marine seismic survey. Nom_Diameter Diameter Nominal (approximate, for naming purposes only) diameter of an object. Nom_Flowrate Flowrate Nominal Flow Rate Nom_Hydraulic_Power Hydraulic_Power Hydraulic (Flowrate x pressure) power that the equipment can sustain over a long period of time, as opposed to maximum working pressure which is the peak maximum Nom_Inside_Diameter Inside_Diameter Nominal (approximate, for naming purposes only) inside diameter of an equipment item. Nom_Length Length Nominal (approximate, for naming purposes only) length of an equipment item. Nom_Liquid_Capacity Volume Volume of fluid which can be contained in the vessel Nom_Max_Outside_Diameter Max_Outside_Diameter Nominal maximum outside diameter, such as for a pilot hole. Nom_Near_Trace_Offset Seismic_Offset Nominal in-line offset between the sources and the first receiver group on each cable (for symmetric configurations) Nom_Outside_Diameter Outside_Diameter Nominal (approximate, for naming purposes only) outside diameter of an equipment item. Nom_Pressure_Loss Pressure_Loss The nominal pressure loss in a piece of equipment, such as a Drill_Motor or an MWD_Tool. Nom_Receiver_Group_Distance Length Nominal distance between consecutive receiver groups Nom_Source_Depth Depth Planned depth for the source Nom_Station_Distance Length Nominal distance between stations on a seismic line Nom_Station_Increment Count Nominal increment in station number for consecutive stations Nom_Thickness Thickness Nominal thickness Nom_Weight Weight Nominal (approximate, for naming purposes only) weight of an equipment item. Nomenclature_Code Code Code built by compounding different codes e.g. drill fluid code built on product-packaging type: 103481052 means Barite API(103481) in 50kg sack (052). Nominal Modifier Approximate, for naming purposes only. For example, the nominal lengths of drill pipe sections may be 30 feet, but the actual length of each section will vary. Nominal_Receiver_Correction Correction Nominal correction vector to receiver position Nominal_Receiver_Dx X_Coordinate X coordinate of nominal correction vector to receiver position. Nominal_Receiver_Dy Y_Coordinate Y coordinate of nominal correction vector to receiver position. Nominal_Receiver_Dz Z_Coordinate Z coordinate of nominal correction vector to receiver position. Nominal_Source_Correction Correction Nominal correction vector to source position Nominal_Source_Dx X_Coordinate X coordinate of nominal correction vector to source position. Nominal_Source_Dy Y_Coordinate Y coordinate of nominal correction vector to source position. Nominal_Source_Dz Z_Coordinate Z coordinate of nominal correction vector to source position. Non_Darcy_Flow_Coefficient Indicator Non-Darcy (turbulence) flow coefficient ("D") Non_Darcy_Skin Skin_Factor The skin effect resulting from turbulent flow conditions within the reservoir or the completion. This is the only skin which is flowrate dependent. Non_Magnetic_Flag Flag A flag indicating whether the equipment is made with non magnetic material. Non_Zero_Sample_Count Count Number of samples that do not have a value of zero. None Property No property code applies; this is a temporary property type used to flag Parameters and Arrays for which we cannot make a meaningful mapping to any Property. Normal_Moveout Time_Interval The additional time required for energy to travel from a source to a flat reflecting bed and back to a geophone at some distance from the source point compared to the time to return to a geophone at the source point. Normalization_Factor Coefficient Coefficient used to normalize data for comparison or correlation. Normalized Modifier The data related to the property has been corrected so that its range corresponds to a prescribed norm. Normalized_Distance Length Normalized distance to the center of a point cluster in multi-dimensional attribute-space. Normalized_Quantity Statistical_Property Normalized property derived by a statistical algorithm normalizing between 0. and 1. the original values of some numerical data; the original data Property code and normalization range may be documented in Remarks. North_Departure Y_Coordinate Displacement to the North relative to some coordinate system origin; e.g., the north component of the well departure from the vertical. (Negative value is departure to the South.) North_South_Distance Y_Coordinate North or South distance to the boundary line indicated by North_South_Line to the survey point. North_South_Line Type Indicates whether the North or South boundary line of the survey area has been used as a reference for North_South_Distance values. Northing_Latitude Latitude Latitude of Northing reference point. Northing_Longitude Longitude Longitude of Northing reference point. Nozzle_Count Count The number of nozzles in an equipment item, such as a drill bit. Nozzle_Size Diameter Diameter of the nozzle(s) used in an equipment item, such as a drill bit Nuclear_Magnetic_Data_Density MWD_Data_Density Density of data samples per length of borehole traversed, for a nuclear magnetism measurement. Object_Identifier Identifier Identifier of the seismic object within the Foreign System Object_Name Name Name of an Object Observed Modifier Seen or sensed especially through directed careful analytic attention. Occurrence Description Description of where an object, material or phenomenon may occur or be found. Occurrence_Order Type The order of occurrence of a particular item. Occurrence_Probability Probability The probability that an item (element, mineral, ..) occur within a particular environment under certain conditions. Offset Multi_Use_Property Difference from a reference value, generally zero. Offshore_Block_Number Identifier Identification of the Offshore block where the well is located Oil_Acoustic_Velocity Acoustic_Velocity Sound velocity of live oil at reservoir pressure and temperature. Typical value is 1000 m/s. Oil_Brine_Ratio Volume_Fraction Ratio of oil volume to brine volume for a fluid, such as an oil based mud Oil_Bubble_Flow_Velocity Flow_Velocity Oil Bubble Velocity Oil_Compressibility Compressibility The compressibility of oil at a given pressure and temperature. Oil_Compressibility_Correlation Name Name of the correlation model (often the author name) used to compute oil compressibility (e.g. Calhoun, Vasquez and Beggs) Oil_Concentration Volume_Fraction Oil Concentration per fluid Volume Oil_Connection_Size Diameter Standard oil pipe size connection supplied on the equipment inlet Oil_Density Density The density of oil. Oil_Flow_Velocity Flow_Velocity Flow velocity of oil component of fluid. Oil_Flowrate Flowrate Rate of flow of oil Oil_Formation_Volume_Factor Formation_Volume_Factor For a sample of oil and its residual solution gas at surface, the ratio of the volume at specified (typically, reservoir) conditions to the volume at surface (stock tank) conditions. Normally abbreviated Bo; typical range 1.1 - 2. Oil_Formation_Volume_Factor_Correlation Name Name of the correlation model (often the author name) used to compute oil formation volume factor (Vasquez_Beggs, Glaso, Standing) Oil_Fraction Volume_Fraction Volumetric fraction of oil in the total fluid Oil_Gravimeter_Type Type Type of instrument used to measure oil specific gravity Oil_Gravity Specific_Gravity The ratio of the density of the produced or reservoir oil to that of pure water at atmospheric conditions. See also API_Gravity Oil_Holdup Holdup Volume fraction of oil in the upward-moving stream of a producing well. Oil_Line_Temperature_Gauge_Type Type Type of gauge used to measure oil line temperature of separator Oil_Mass_Flowrate Mass_Flowrate Mass flowrate of oil. Oil_Metering_Line_Size Diameter Diameter of the oil metering line Oil_Probability Probability The probability that oil is present in the formation. Oil_Rate_Meter_Type Type Type of liquid meter used to measure oil rate Oil_Sampling_Point Location The location where oil samples are taken on the separator Oil_Saturation Saturation The extent to which the pore space in a formation contains oil. Oil_Temperature Fluid_Temperature The temperature of oil under certain conditions. Oil_Viscosity Viscosity The viscosity of oil at specific temperature and pressure conditions. Oil_Viscosity_Correlation Type Model used to compute oil viscosity Oil_Volume_Fraction Volume_Fraction The volume fraction of oil with respect to the total volume; the product of Porosity and Oil_Saturation Oil_Water_Contact_Depth Depth The depth at which oil water contact has been recognized in a Reservoir Unit. Oil_Water_Ratio Volume_Fraction Ratio of oil volume to water volume for a fluid, such as an oil based mud Oil_Wettability_Index Wettability_Index Relative affinity of a mineral surface for oil. Amott One_Hour_Pressure Pressure Pressure measured 1 hour after start of test. One_Way_Time Acoustic_Travel_Time The time required for an acoustic wave to travel directly from one point to another; used to distinguish from Two_Way_Time. Open_Fraction Ratio Fraction to which the equipment is open, e.g., 50% open Operating_Mode Type Operating mode of an equipment Operating_System_Name Name Name of computer Operating System, e.g. Unix, VMS, Windows NT. Operating_System_Version Version Version of computer Operating System Operating_Time Time_Interval Period of time which is spent operating, either for a single operation or for a series of operations. Complement of Idle_Time. Operator Organization_Code The code of an operator, usually that of a Service, Contractor, Vendor or E&P company Operator_Name Organization_Name The name of an operator of a well, an equipment, etc. Optimum_Flag Flag Indicates whether the activity, process or solution is optimum. Optional_Blade_Height Blade_Height Optional height of blade at gauge from the body of the equipment, such as a stabilizer (extended Andergauge); used as a supplement to Blade_Height. Ordered_Flag Flag Flag to indicate whether the members of a set have been ordered. Ordinal_Number Data_Valued_Property A number used to indicate the position, rank or order of items in a sequence. Organization_Code Code Catalog-controlled code of Organization. Organization_Name Name Name of organization Organization_Role Type Role of organization (e.g. Business Associate) Orientation Data_Valued_Property The spatial orientation of an object. Usually defined by a vector who origin location is known relative to a coordinate system (e.g., in spherical coordinates, the Vector will be defined by the 3 angles Rho, Theta and Phi) Orifice_Meter_Gas_Temperature Temperature Temperature of gas at orifice meter line when a sample is taken Orifice_Plate_Diameter Diameter Diameter of orifice plate in gas metering system when a sample is taken Origin_Easting X_Coordinate The easting of the point of origin of an orthogonal grid constructed on a map projection. Often, this value is defined to be a positive number to avoid negative coordinates. Sometimes called "false easting". Origin_Latitude Latitude The latitude of the point of origin of an orthogonal grid constructed on a map projection. Frequently this is a projection standard parallel, but can be any defined latitude. Origin_Longitude Longitude The longitude of the point of origin of an orthogonal grid constructed on a map projection. Frequently this is the central meridian, but can be any defined longitude Origin_Northing Y_Coordinate The northing of the point of origin of an orthogonal grid constructed on a map projection. Often, this value is defined to be a positive number to avoid negative coordinates. Sometimes called "false northing". Origin_Rho Radius Radial distance of the origin of a Local Coordinate System, measured with respect to the origin of the "from" coordinate system. Units, if any, are those of the "from" system. Origin_X X_Coordinate X component of the location of the origin of a Local Coordinate System, measured with respect to the origin of the "from" coordinate system. Units, if any, are those of the "from" system. Origin_Y Y_Coordinate Y component of the location of the origin of a Local Coordinate System, measured with respect to the origin of the "from" coordinate system. Units, if any, are those of the "from" system. Origin_Z Z_Coordinate Z component of the location of the origin of a Local Coordinate System, measured with respect to the origin of the "from" coordinate system. Units, if any, are those of the "from" system. Original_Expiry_Date Expiry_Date The original date that the contract was to terminate. If the contract is extended, this date does not change. Orthoclase_Volume_Fraction Volume_Fraction The volume fraction of orthoclase with respect to the total volume. Outer_Boundary_Condition_Type Type Description of the outer boundary condition for a well test model. Outer_Continental_Shelf_Name Name Name of the submerged land area called the Outer Continental Shelf Outer_Pipe_Inside_Diameter Inside_Diameter Inside diameter of a pipe in external position within an annulus Outlet_Connection_Size Diameter The connection size of the output line to the equipment Output_Pressure Pressure Pressure at the output of an equipment item. Outside_Diameter Diameter Outside diameter of an entity, such as an item of drillstring equipment Ovality Shape Degree of departure from roundness. Often measured as the ratio of large diameter over small diameter of an ellipse or an ellipsoid body Overbalance_Pressure Pressure The difference between formation pressure and the pressure of the fluid in the borehole. Overburden_Pressure Pressure The pressure exerted on the matrix of a porous media by the weight of overlying strata. Owner_Name Organization_Name The name of the owner of an item like a piece of equipment. Ownership_Amount Proportion Lessor percentage ownership Oxygen_Yield Elemental_Yield Elemental contribution of Oxygen with respect to total. PI_Code Identifier Petroleum Information Alpha-Numeric code PI_Code_Series Identifier Petroleum Information Alpha-Numeric code series. Example 110 for Producing Wells, 400 for Gas Injection Wells. P_Wave_Angle Plane_Angle P-wave angle Package_Size Amount Quantity of material contained in each package. Unit depends upon the type of material and packaging. Packaging_Code Code Identifier of the packaging e.g. 303: 50 gal Drum Packaging_Type Type Type of Packaging or container used for products, such as Drum, Sack, Bulk, Pieces, Pallets Packaging_Unit Code Code of a packaging unit Packer_Depth Depth Depth at which the packer is set. Packer_Inside_Diameter Inside_Diameter Packer internal diameter (Casing_Tubing Packer) Packer_Motion_Type Type Internal tubular (e.g. tubing) motion allowed by the packer during an increase in pressure. Choices: Free (Packer does not restrain motion), Limited (tubular is free to shorten but not lengthen) and No Motion. Packer_Type Type Type of packer; supplier type like Dowell Model 21. No simple type description available but the supplier identification. Pad_Force Force Tool pad force Pad_Pressure Pressure The pressure with which the pad of a logging or testing device is applied to the formation or other interface. Parallel_Porosity_Volume_Fraction Volume_Fraction The volume fraction of parallel porosity with respect to the total volume. Parameter_Label Annotation String carrying the short explanation of a parameter, for use in user interface Parent_Code Code Code of the supertype or parent of this object type. Part_Number Identifier Identifier used for accounting or purchasing purpose to identify an equipment item. Partial_Completion_Model Type Model used to compute the Partial Completion apparent skin effect Partial_Completion_Skin Skin_Factor The skin effect caused by flow convergence due to not completing the entire flowing thickness. Does not include the skin due to the completion itself. Particle_Displacement Displacement The distance a particle is moved from its equilibrium position, as in ground motion associated with a seismic wave. Pass_Through_Diameter Inside_Diameter Equipment (e.g. drillbit) attribute which specifies the minimum inside diameter of casing through which the equipment will pass. Pattern_Length Interval_Length The length of a pattern, usually pertaining to a dip pattern or a geological feature. The length is usually an interval length like depth. Pattern_Name Name Name of a pattern or style, such as a graphic pattern. Peak_Peak_Amplitude_Ratio Ratio Ratio of amplitudes of two peaks. Peak_Peak_Delta_Amplitude Amplitude Amplitude difference between two peaks. Peak_Peak_Delta_Depth Thickness Depth difference between successive peaks Peak_Peak_Delta_Time Time_Interval Time difference between two peaks. Peak_Trough_Amplitude_Ratio Ratio Ratio of amplitudes of peak and trough. Peak_Trough_Delta_Amplitude Amplitude Amplitude difference between peak and trough. Peak_Trough_Delta_Depth Thickness Depth difference between peak and trough where peak occurs first in increasing depth Peak_Trough_Delta_Time Time_Interval Time difference between peak and trough. Penetration_Depth Depth Depth to which some medium is penetrated, such as by a drill bit or probe, or by fluid invasion. (Not to be used for borehole depth.) Penetration_Rate Velocity Usually used to describe the rate at which a formation is penetrated during drilling operation. In general, the rate at which an equipment penetrates a surface or subsurface volume. Perforation_Charge_Type Type Type of explosive charge used in a perforating gun. Perforation_Count Count Total number of perforations over the perforated interval Perforation_Diameter Diameter The diameter of the perforation entrance hole. Often called Entrance Hole Diameter. Perforation_Distance Interval_Length Distance from the top of the hydraulic unit to the top of the perforations. For use in the partial penetration model. Perforation_Gun_Phase Type Phasing of the perforating gun for the given perforated interval. Standard phasings include Inline (0 deg), Spiral (45, 60, 90, 120, 180 deg), Tangential(90-270 deg). Perforation_Gun_Position Type The position of the perforating gun relative to the tubing/casing in the borehole. Options include: Positioned (usu. Through-Tubing guns), Not Positioned (usu. Casing guns), Centralized. Perforation_Gun_Standoff Standoff Standoff of Perforation Gun Perforation_Gun_Type Type The type of perforating gun used to shoot the given interval of the tubing (or casing) in the borehole. Examples are: 3-3/8" 6 SPF, 3-3/8" HJ HI-TEMP, 4" HJ II, etc. Perforation_Length Length Length of the portion of the perforation which extends from the casing beyond the cement sheath and into the reservoir. It includes the casing thickness and the cement sheath thickness. Perforation_Pressure_Condition Flag Pressure condition in the well at the time of perforating; may be Underbalanced (pressure in formation higher than in borehole) or Overbalanced (pressure in borehole higher than in formation. Perforation_Shot_Density Data_Valued_Property The perforation density; i.e., the number of shots per unit length. Perforation_Status Status Not perforated, perforated, plugged or squeezed Perforation_Type Type The method used to open the production in the borehole. Examples are: Bullet, Jet, Combination, Open Hole, etc. Period Time_Interval The time T for one cycle of a periodic function. The time for a wave crest to traverse a distance equal to one wavelength. The reciprocal of Frequency. Permeability Data_Valued_Property A property of rock (formation) denoting its ability to pass fluids through its interconnected pores. Permeability_Axial_Path Directional_Permeability Permeability measured along the length of a core cylinder. Permeability_Thickness Volume The product of permeability and thickness of the body acting as a conduit. Permeability_Thickness_Ratio Ratio Ratio of component permeability-thickness to total system permeability-thickness [kh(i) / kh(total)], usually known as Kappa in reservoir dynamics work. Permeability_Transverse_Path Directional_Permeability Permeability measured in the plane transverse to the length of the core cylinder. This may be represented as a single measurement in the flow plane or as a two component permeability represented as a measurement along an arbitrary diameter and another along an orthogonal path in the same plane. Permittivity Data_Valued_Property The property of a material that enables it to store electrical charge, typically measured in farad/m. Free space has a Permittivity of 8.854E-12 farad/m. Person_Name Name Name of a person Personnel_Count Count Headcount of personnel satisfying role of Personnel_Role; these may be implemented as lists. Personnel_On_Board Count Count of number of people on board the vessel or structure. Personnel_Role Type Role of the personnel counted in Personnel_Count; these may be implemented as lists. Perspective_Height Height Height of the point of perspective; used in general perspective map projections. Pf_Titration_Volume Volume Amount of 0.02 normal (N/50) standard sulfuric acid required in order to turn the color of phenolphthalein indicator solution from pink to colorless when determining phenolphthalein alkalinity of the mud filtrate, Pf, API RP13 Section 8, Chemical Analysis. Phase_At_Envelope_Maximum Instantaneous_Phase Instantaneous phase at maximum of reflection strength. Similar to Response_Phase, but with maximum within a user-defined interval. Phase_Shift Plane_Angle The result of adding or subtracting from a phase measurement. Phase_Shift_Resistivity Electromagnetic_Propagation_Resistivity Formation resistivity as measured by the phase shift of a high frequency electromagnetic wave (hundreds of KHz to several MHz, 1.1 GHz in the case of Schlumberger's EPT tool); these measurements are typically sharp (good vertical resolution) and have good dynamic range, but their depth of investigation is less than that of measurements based on attenuation. Phase_Velocity Acoustic_Velocity The velocity of any given phase (such as a trough) or a wave of single frequency; may differ from Group Velocity due to dispersion in the medium. Phone_Number Address Telephone number Phosphorus_Yield Elemental_Yield Elemental contribution of Phosphorus with respect to total. Photoelectric_Factor Data_Valued_Property A measure of the probability that scattering due the Photoelectric Effect will occur; often expressed in an approximation unit barns/electron. Photoelectric_Factor_Quality_Indicator Quality_Indicator Property used to indicate quality or confidence of data from a photoelectric factor survey. Pick_Quality Quality_Indicator Pick quality measurement. Pickup_Friction_Coefficient Coulomb_Friction_Coefficient Friction coefficient between a string and the borehole when pulling out of the hole Pickup_Hook_Load Hook_Load Driller estimate of the average pickup hook load (pickup weight) over the reporting period. Pickup_Reel_Back_Tension Tension Amount of tension kept on the coiled tubing between the gooseneck and the reel when pulling out of the hole Pipe_Inside_Diameter Inside_Diameter Inside diameter of pipe Pipe_Outside_Diameter Outside_Diameter Outside diameter of pipe Pitch_Length Length Measure of slope using the linear distance between two successive points: on a screw, between threads, measured parallel to the axis; for a propeller or spinner, the theoretical axial displacement corresponding to one revolution. Plane_Angle Data_Valued_Property The angular displacement between two lines extending from the same point, measured in the plane of the two lines. Plane_Angle_Unit Unit_Code Unit for Plane Angle data Plane_Type Type The type of a plane in the Earth subsurface, e.g. Bed Plane, Fault Plane, Fracture Plane, etc. Planned_Depth Measured_Depth The planned measured depth at the end of the reporting period, as described on the driller depth log of the planned borehole Plastic_Viscosity Viscosity Apparent viscosity of the Bingham Plastic model : Slope of the curve shear stress vs. shear rate (rheogram). Model equation is Shear_Stress = Yield_Stress + Plastic_Viscosity times Shear_Rate. Platform_Type Type The type of a platform. Play_Type Type A type or code assigned to a lease. Play codes can be internal to company and are usually based upon geographic boundaries or geologic trends. Plug_Back_Total_Depth Depth Measured Depth of the current bottom of the borehole. It is the physical bottom of the borehole which is plugged either by a cement or by a mechanical plug. The P.B.T.D. can changes in time. It is smaller than the total depth drilled. Plunger_Count Count Number of plungers e.g. 3 for a triplex pump. Plus_Tolerance Tolerance Amount of positive tolerance on a measurement value; the unit quantity is determined by that of data value. Pm_Titration_Volume Volume Amount of 0.02 normal (N/50) standard sulfuric acid required in order to turn the color of phenolphthalein indicator solution from pink to colorless when determining phenolphthalein alkalinity of the mud, Pm, API RP13 Section 8, Chemical Analysis. Point_Type Type The type of an Earth zero-dimensional object such as a marker. Poisson_Ratio Ratio Ratio of the transverse contraction of a body to its longitudinal extension when stretched. Typical values in minerals are from 0.15 to 0.3 (Carbonates:0.15, Sandstones:0.2, Shales:0.25). Polarity_Ratio Ratio Ratio of number of positive samples to total number of samples. Equivalent to Threshold_Ratio where threshold is zero. Polarity_Reversal_Flag Flag When set, apply reverse polarity. Polarization_Azimuth Azimuth Shear energy polarization azimuth angle measured clockwise from grid north. Polynomial_Order Ordinal_Number Order of term in a polynomial, such as in a multiple regression equation. Polyol_Concentration Chemical_Concentration Polyol Concentration per fluid Volume (Polyol are glycol-glycerol alcohol derivatives) Pond_Depth Depth For a centrifuge, Position of overflow Port relative to Inner Bowl Wall Population Count A count of the number of persons or objects. Pore_Pressure Pressure The pressure of the fluid contained in the pore volume. Pore_Pressure_Gradient Pressure_Gradient The change in pore pressure per unit length. Pore_Pressure_Safety_Factor Safety_Factor Amount by which borehole pressure should normally exceed pore pressure, to allow for uncertainty in pore pressure estimation. Pore_Throat_Diameter Diameter The measured or effective diameter of the aperture which connects pores or void spaces within a rock matrix. Pore_Volume Volume The volume within a geologic volume that describes the connected void space within the matrix of rock. Pore_Volume_Compressibility Compressibility The relative change in the pore volume of a rock under conditions of changing confining pressure. Porosity Volume_Fraction Pore volume per unit gross volume. Porosity is determined from measurements on cores or interpreted from logs. Porosity_Correction Correction Correction to a Porosity measurement. Porosity_Length_Ratio Ratio The ratio of the sum of layer porosity thicknesses to total system porosity thicknesses for a layered porous media. Porosity_Type Type The porosity type usually of a core sample or in either a carbonate or clastic rock formation (e.g. Intercrystal, Breccia, Vuggy, etc.), Port_Count Count Number of ports, such as in a Coiled Tubing BHA Port_Diameter Diameter Diameter of each individual port Positive Modifier Real and numerically greater than zero. Positive_Slope Multi_Use_Property Positive slope value. Positive_Threshold Threshold Positive threshold value. Post_Cursor_Amplitude Amplitude Difference in seismic amplitude between a reference position and the corresponding deeper extreme. Postal_Address Address Location to which postal correspondence may be sent for a person, business or other entity. Potash_Volume_Fraction Volume_Fraction The volume fraction of potash with respect to the total volume. Potassium_Concentration Concentration Concentration of Potassium by weight. Potassium_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of potassium to total dry weight Potassium_Ion_Concentration Chemical_Concentration Potassium K+ cation concentration Potassium_Yield Elemental_Yield Elemental contribution of Potassium with respect to total. Power Data_Valued_Property The time rate at which work is done or energy emitted or transferred. Power_Supply_Start_Time Start_Time Actual date and time at which the recorder was powered on. Pre_Cursor_Amplitude Amplitude Difference in seismic amplitude between a reference position and the corresponding shallower extreme. Precision Statistical_Property The repeatability of an instrument measured by the mean deviation of a set of measurements from the average value; the unit quantity is determined by that of the data. Preferred_Flag Flag An indicator which shows that a particular item is preferred over another, normally as a result of some interpretation or validation process. Preparation_Method Method_Type Method by which an item or sample has been prepared for subsequent operations or analysis. Prescale_Offset Multi_Use_Property Special Offset value used in certain calibrations It is not part of the Calibration_Coefficient list. Preservation_Method Method_Type Method by which an item or sample, such as a core sample, has been preserved. Pressure Data_Valued_Property The force or thrust exerted over a surface divided by its area; e.g., hydrostatic, flow, pump, etc. May be gauge or absolute. Pressure_Accuracy Accuracy The maximum difference, over the calibrated range, between pressure applied to the gauge, with a reference standard, and the pressure measured by the gauge. Pressure_Digit Pressure Element of a representation for pressure data in which each digit in the decimal pressure (1's, 10's, 100's, etc. )is stored as a separate unitless digit. This method is obsolete, but the property is needed for mapping historical data. Pressure_Drop_Correlation Type Pressure drop correlation (e.g., Dun-Ros, Cullender, ) Pressure_Drop_Correlation_Type Type Pressure drop correlation (e.g., Dun-Ros, Cullender, etc. ) Pressure_Gradient Gradient The change in pressure per unit length. Pressure_Loss Pressure The difference between input and output pressure, usually due to friction. Pressure_Measure_Point Measure_Point_Offset The distance from the bottom of the Equipment to the point where the pressure is measured. Pressure_Operation_Type Type Type of pressure-operated mechanism. Certain tools are be operated by either tubing or annulus pressure. These tools frequently contain a rupture disk or break plug and are single-shot. Pressure_Point_Setup Type Identifies the location of the fluid whose pressure is being recorded. Pressure_Point_Setup_Code Code Encoding of the pressure point position setup of a Testing Tool by concatenation of the PRESSURE_POINT_SETUP enumeration separated by space, e.g., "Tubing-Above-Valve Annulus Empty" Pressure_Rate Data_Valued_Property A measure of the rate at which pressure varies per time; e.g., slider pressure correction. Pressure_Sensor_Code Code Pressure sensor code Pressure_Sensor_Drift Pressure Pressure difference over time in the gauge output with constant input conditions Pressure_Sensor_Noise Noise_Amplitude Random changes in pressure sensor response. Pressure_Sensor_Resolution Pressure The minimum significant pressure change that can be detected above the noise. This is measured as the standard deviation of the differences between two successive measurements. Pressure_Sensor_Type Sensor_Type Pressure sensor type Pressure_Unit Unit_Code Unit for Pressure data Primary_Output_Flag Flag Flag indicating that data constitute a valid primary output (1) or an auxiliary output (0) Primary_Porosity Porosity The porosity remaining after sediments have been deposited but without considering changes because of subsequent chemical action or water flow. Prime_Meridian_Greenwich_Offset Longitude Longitude of the prime meridian referenced from the meridian through Greenwich. Positive denotes east of Greenwich. Example: PARIS PANTHEON meridian in France is at longitude 2.337229 degrees. Prime_Meridian_Name Name Name of the meridian from which longitudes are referenced. Normally the meridian through Greenwich is defined as the prime meridian. Principal_Meridian Longitude Principal Meridian of Jeffersonian_Parcel Priority Data_Valued_Property Superiority in rank, position, or privilege Probability Data_Valued_Property The likelihood that a given event will occur, expressed as the ratio of the number of occurrences of the specified event to the total number of events. Processing_Option Indicator An indicator of which of two or more options has been selected for data processing. Processing_Window_Length Interval_Length Length of processing window Processing_Window_Length_Depth Interval_Length Length of processing window in depth domain Processing_Window_Length_Time Time_Interval Length of window in time domain Produced_Fluid_Compressibility Compressibility Compressibility of the Total Produced Fluid for the Hydraulic Unit. It is corrected from Reservoir_Fluid_Compressibility by taking into account the actual volume fractions produced based on the saturation of the fluid within the reservoir. Producing_Gas_Liquid_Ratio Gas_Liquid_Ratio The ratio of produced gas to produced liquid (oil + water) at the wellhead Producing_Thickness Thickness Total flowing thickness along the Borehole ("Hp") Producing_Water_Cut Water_Cut Producing Water Cut from the Hydraulic Unit Product_Code Code The code of a chemical product sometimes named alphacode e.g. D013 Product_Name Name Official product name. Production_History_Flag Flag Flag indicating whether or not this Flow Period is part of the Production History; i.e., set for Production History, not set for Test History Production_History_Reference_Time Reference_Time Reference Date and Time for Production History Production_History_Type Type Type of production/Injection data set : Previous_Flow_History (Production), Injection, Previous_Flow_History (Production), Simulated_Behavior (Test), Actual_Field (Flow) Productive_Flag Flag Indicates whether object or activity is productive. An activity is considered productive if it brings the operation closer to achieving the objective. Productivity_Index Mobility Ratio of flow rate to pressure drop. For oil wells, PI is normally expressed in barrels per day per psi decline in bottomhole flowing pressure. Productivity_Ratio Ratio Productivity ratio (actual productivity index divided by ideal (zero skin) productivity index) Profile_Conductance Conductance Measurement related to conductance but not necessarily scaled or calibrated for quantitative use. Profile_Conductivity Conductivity Conductivity profile measurement, used primarily for pattern recognition; may or may not be calibrated. Profile_Resistivity Resistivity Resistivity profile measurement, used primarily for pattern recognition; may or may not be calibrated. Projection_Azimuth Azimuth Azimuth of positive y-axis of projection. Projection_CS_Type Type The type of a Projection coordinate system, e.g. Lambert, UTM, State Plane, etc. Projection_Class Type Base projection type (e.g. TM for UTM_1) Projection_Code Code Catalog code of a Projection coordinate system. Projection_Name Name Name of the projection coordinate system. Projection_Point_Mode Flag Flag determining number of points used in defining certain projections, 0,1,2 Projection_Quadrant Flag Quadrant in which X and Y axes are positive, 1,2,3, or 4 Projection_Relative_Bearing Azimuth Projection relative bearing Projection_Scale_Factor Scale_Factor Scale Factor which is used as a defining parameter for a projection, typically taken along the Central Meridian or along one of the major parallels Projection_Scale_Reduction Scale_Factor A number by which the scale along a designated meridian, great circle, or parallel is reduced or enlarged during the projection process to reduce the scale error elsewhere in the projection. Projection_Zone_Code Name UTM Zone of projection. Property Any SDM Property defined in this catalog Property_Code Code Catalog code of SDM Property Proportion Ratio The ratio of one part of an amount to the whole, with respect to quantity or magnitude. Proposal_Number Identifier Customer proposal number Proppant_Areal_Distribution Concentration Mass of proppant per fracture area (hydraulic fracturing) Proppant_Concentration Concentration Proppant concentration expressed as mass of proppant added per gallon of gel, legacy (LIS) unit "PPA" Proppant_Density Density The density of the proppant material Proppant_Permeability_Factor Ratio Fraction of proppant permeability retained in the in-situ fracture condition, and due to mechanical damage excluding any damage due to fluid residue. Has the same effect than Fluid_Permeability_Factor. Propped_Bottom_Depth Depth Bottom Depth of proppant laden slurry volume during the propagation of an hydraulic fracture considered along the well bore.. Propped_Half_Length Length Half Length of the part of an hydraulic fracture which is filled by proppant laden slurry . It is shorter during fracture propagation than the fracture half_length as the propped slurry follows a gel volume w/o proppant , the "clean" fluid Propped_Top_Depth Depth Top Depth of proppant laden slurry during the propagation of an hydraulic fracture considered along the well bore. Often named Slurry height. At fracture closure, Propped_Top_Depth = Fracture_Height. Propped_Width Width Width of the proppant laden volume within an hydraulic fracture (hydraulic fracturing). Smaller during fracture propagation than the fracture width. Pseudo Modifier Spurious. Pseudocritical_Pressure Critical_Pressure The pressure needed to condense the vapor of a gas mixture at its pseudocritical temperature. Analogous to Critical_Pressure for pure components. Pseudocritical_Temperature Critical_Temperature The highest temperature at which a fluid can exist as a liquid and above which its vapor cannot be liquefied regardless of the amount of pressure. Used for mixtures, analogous to Critical_Temperature for pure components. Publication_Date Date Date of publication of a document. Publication_Title Title Title of publication of a document. Publisher_Name Organization_Name Name of Organization which published of a document. Pump_Liner_Diameter Diameter Diameter of the pump entry line Pumping_Schedule_Type Type Type of pumping schedule i.e. as measured, design, alternate... Pumping_Time Operating_Time Elapsed time during which pumping has taken place. Purchase_Number Identifier Purchase Order Number Put_Function_Name Function_Name Name of function used to write data. Pyrite_Volume_Fraction Volume_Fraction The volume fraction of pyrite with respect to the total volume. QHSE_Report_Count Count Number of QHSE reports issued for the reporting period Q_Ratio Ratio Quality factor for compressional waves. The ratio of 2*pi times the peak compressional wave energy to the energy dissipated in a cycle. Qs_Ratio Ratio Quality factor for shear waves. The ratio of 2*pi times the peak shear wave energy to the energy dissipated in a cycle. Quality_Factor Data_Valued_Property Factor which quantitatively characterizes the acoustic attenuation of a medium. Quality_Indicator Indicator Property which provides a relative measure of the quality or fitness-for-purpose of data, or of some item, process, or material. Quartz_Volume_Fraction Volume_Fraction The volume fraction of quartz with respect to the total volume. RMS_Amplitude Amplitude Root Mean Square of amplitudes. RMS_Velocity Acoustic_Velocity Transit-time weighted root mean square of the interval velocities over a series if intervals. RP66_Array_Code Array_Code Code or Identifier of this type of RP66 Channel object. RP66_Index_Code Code Code or Identifier of an RP66 axis index measured or computed by some activity, e.g. MD, TVD, etc. RP66_Parameter_Code Code Code or Identifier of this type of RP66 Parameter object. Radial_Length Length Length measured in a radial direction. Radioactivity Data_Valued_Property The measure of intensity of radiation from a material relative to a standard level of intensity. Radius Length Radius of an entity with a spherical or cylindrical shape, such as the borehole, an item of drillstring equipment, etc. Ramping_Duration Time_Interval Time duration of the ramp tapering the time window Ramping_Method Method_Type Method to ramp (tapering) the time window, e.g., Hamming, Hanning... Range_Number Identifier Jeffersonian Range Number Range_Type Type Specification whether the value range is inclusive[], exclusive (), or mixed: [) or (]. Rank Ordinal_Number Integer denoting the order of an element in a collection, such as the rank of a Layer participating in a Sequence or Stratigraphic Column. Rat_Hole_Bottom_Depth Bottom_Depth Bottom depth of the section of the borehole running from the tester valve to the effective bottom of the well Rat_Hole_Diameter Inside_Diameter Diameter of the section of the borehole running from the tester valve to the effective bottom of the well Rat_Hole_Volume Volume Available volume of fluids below testing valve. The rat hole is the section of the borehole running from the tester valve to the effective bottom of the well. The calculation of this volume is not straight-forward as the rat hole is not generally empty. Ratio Data_Valued_Property The value of one item divided by the value of another item. Raw Modifier Data which are uncalibrated and/or uncorrected; such data should be interpreted with caution. Raw_Relative_Bearing Azimuth Raw relative bearing Ray_Velocity Group_Velocity The velocity in the direction of energy transport; in anisotropic media it is different from the direction in which the phase velocity is measured. Also called group velocity. Rayleigh_Slowness Acoustic_Slowness The acoustic slowness of a Rayleigh wave (type of seismic wave propagated along the free surface of a semi-infinite medium). Rayleigh_Velocity Acoustic_Velocity The velocity of a Rayleigh wave (type of seismic wave propagated along the free surface of a semi-infinite medium. Reactance Impedance The opposition to alternating current flow offered by inductance or capacitance; the quadrature component of impedance. Read_Only_Flag Flag Flag indicating that a record is available for read access only (cannot be updated or deleted). Receiver_Event_First_Arrival Time_Interval Time of arrival of first break for each receiver event Receiver_Group_Count Count Total number of receiver groups attached to the cable Receiver_Line_Position Cylindrical_Position Position in a receiver line Receiver_Line_Rho Radius Horizontal (x-y) distance from origin of position in a receiver line. Receiver_Line_Theta Theta_Angle Horizontal angle of position in a receiver line, measured counter-clockwise from x-axis. Receiver_Line_Z Z_Coordinate Z-coordinate of position in a receiver line. Receiver_Offset Seismic_Offset The distance to a seismic receiver from some other object, such as a wellbore in VSP work. Receiver_Orientation Spherical_Position Downhole receiver orientation vector Receiver_Orientation_Phi Inclination Vertical angle of downhole receiver, measured from the x-y plane. Receiver_Orientation_Rho Radius Horizontal (x-y) distance from origin of downhole receiver. Receiver_Orientation_Theta Theta_Angle Horizontal angle of downhole receiver, measured counter-clockwise from x-axis. Receiver_Station_Datum_Elevation Elevation Datum elevation at each station relative to sea level Receiver_Station_Time Time_Interval Time of first measurement for each station since the Origin_Time stored in Seis_Survey_Area Reconstructed Modifier Rebuilt from other criteria. Record_Length Byte_Count Total record length in bytes, such as for a seismic trace header. Recorded Modifier Permanently registered. Recorder_Code Code Code for the recorder Recorder_Delay_Time Time_Interval Delay time between instrument power-on time and when recording begins Recorder_Scanning_Rate Data_Valued_Property Scanning rate at which gauge records data Recorder_Type Type Recorder type Recovery_Factor Volume_Fraction Recovery factor of reservoir fluids expressed as the ratio of standard volumes (stock tank barrels, etc.) recovered to pore volume. Recovery_Ratio Ratio Ratio of amount of sample or material recovered to total amount recoverable. Rectangle_Length Reservoir_Distance The length distance between two parallel boundaries in a rectangular reservoir model. Rectangle_Width Reservoir_Distance The width distance between two parallel boundaries in a rectangular reservoir model. Rectangular_Position Location Set of coordinates specifying the position of a point in a rectangular coordinate system Reduced_Pressure Ratio The pressure of a fluid divided by the critical pressure of the fluid. Reduced_Temperature Ratio The temperature of a fluid divided by the critical temperature of the fluid. Reduced_Traveltime Time_Interval Difference between observed refraction traveltime and the traveltime which would have been observed if only one head-wave velocity had been involved. Reduced_Volume Volume_Fraction The volume of a fluid divided by the critical volume of the fluid. Reel_Core_Diameter Diameter Drum core diameter, such as for a coiled tubing reel Reel_Core_Width Width Width between flanges of the drum core, such as for a coiled tubing reel Reel_Inlet_Pressure Pressure Pressure at the inlet of a coiled tubing reel. Reference_Depth Depth Depth value used as a reference for other data Reference_Location Location Location used as a reference for other data. Reference_Pressure Pressure Reference Pressure, as for a PVT computation Reference_Sack_Mass Mass Sack "weight" (mass) to which unit by sack refers e.g. lbs/sack Reference_Time Absolute_Time Reference Date and Time For Elapsed Time Reflection_Angle Plane_Angle The angle which the raypath of a reflected ray makes with the perpendicular to the interface. At the "reflection point" it is equal to the Incident_Angle for pressure-pressure or shear-shear reflections. Reflection_Coefficient Ratio Ratio of the displacement amplitude of a reflected wave to that of the incident wave. Also called Reflectivity. Reflection_Coefficient_Threshold Reflection_Coefficient Minimum reflection coefficient when processing the multiple reflections Reflection_Heterogenity Amplitude An indirect measure of how much a reflection signal is changing or of how erratic a trace is. A constant has a Reflection_Heterogenity of 0. Heterogeneity can be computed from any of several signals, including seismic data, instantaneous phase, instantaneous frequency, apparent polarity and reflection strength. Reflection_Intensity Data_Valued_Property Rate of flow of wave energy through a unit area perpendicular to the direction of wave travel; for a seismic wave, intensity is proportional to the square of the amplitude of displacement or velocity. Reflection_Strength Analytic_Trace Amplitude of analytical seismic trace (Hilbert transform technique). Synonym of Instantaneous_Amplitude. Reflection_Strength_Slope Slope Least squares slope (gradient) of reflection strength in an interval. Refractive_Index Data_Valued_Property The ratio of the velocity of light in a vacuum to that in the medium in question. Region_Of_Interest Name Geopolitical area of interest Regularization_Factor Data_Valued_Property Factor used in T2 inversion (nuclear magnetic resonance logging) to ensure the continuity of the T2 distribution as a function of the signal to noise ratio. Related_Sample_Type Type Type of related samples taken in the recombination set Relation_Valued_Property Property A Property whose value is a reference (pointer) to another Entity. Relationship_Constraint_Type Type Type of constraint for a relationship, such as Restrict, Cascade, or Nullify. Relationship_Type Type Type of relationship between two objects: Containment, Reference, Supertype, Catalog,etc. Relative_Apparent_Resistivity Resistivity The ratio of apparent resistivity to the true resistivity of a portion of a reservoir model (like a two-layer model). Relative_Bearing Plane_Angle Angle measured clockwise from top of hole to tool angular reference point in the plane perpendicular to the tool axis, viewed from above the tool. Relative_Dip_Angle Dip_Angle Magnitude of formation dip relative to structural dip; computed by subtracting structural dip from true dip (dip removal). Relative_Dip_Azimuth Dip_Azimuth Azimuth of formation dip relative to structural dip; computed by subtracting structural dip from true dip (dip removal). Relative_Permeability Permeability The ratio of effective permeability divided by the absolute permeability; e.g. the relative permeability of a rock to that of any of its contained fluids. Relative_Permeability_Basis Type Absolute or effective permeability basis for the relative permeability. Relative_Permeability_Function Function_Name Name of the function used to represent relative permeability. Relative_Permeability_Function_Coeff Coefficient Coefficients used in the function. Relative_Permeability_Gas Relative_Permeability Ratio of effective gas permeability to absolute permeability. Usually abbreviated as Krg Relative_Permeability_Oil Relative_Permeability Ratio of effective oil permeability to absolute permeability. Usually abbreviated as Kro. Relative_Permeability_Water Relative_Permeability Ratio of effective water permeability to absolute permeability. Usually abbreviated as Krw. Relaxation_Time Time_Interval In nuclear magnetic resonance measurements, the time constant related to the rate at which nuclei realign to the static magnetic field after disturbance by a radio frequency pulse. Relaxation_Time_Ratio Ratio In nuclear magnetic resonance logging, the ratio of longitudinal to transverse relaxation time; used to determine polarization correction. Remaining_Life Operating_Time Remaining relative life predicted by the CoilLIFE model expressed as a percentage Remaining_Volume Volume Volume of material which remains (e.g. remaining volume to be pumped) Remarks Data_Valued_Property Any type of remarks added to an entity instance. Remote_File File_Name Name of file on remote host Report_Date Date Date (time) when report was completed or issued. Report_Flag Flag Flag indicating the presence of a report, or that an item or event is to be included in a report. Representation_Attribute Attribute_Name Object Attribute name where Representation may be found if not specified. Representation_Code Code Catalog code of the Representation Representation_Object Object_Name Object instance name where Representation may be found if not specified. Representation_Type Type The type of computer representation used to manipulate a property value, e.g. Grid, Array, Primitive, etc. Reservoir_Distance Length The distance between two features in a reservoir, for use in modeling the reservoir. Reservoir_Fluid_Compressibility Compressibility Compressibility of the reservoir fluid Reservoir_Fluid_Density Density The density of the reservoir fluid i.e. the mixture oil, gas and water. Reservoir_Fluid_Viscosity Viscosity The viscosity of reservoir fluid at specific temperature and pressure conditions. Reservoir_Gas_Oil_Ratio Gas_Oil_Ratio The ratio of gas to oil of the reservoir fluid at reservoir condition Reservoir_Type Type Description of the reservoir type for a well test model. Residual_Gas_Saturation Saturation The fraction or percentage of gas remaining following production from the reservoir. Residual_Hydrocarbon_Saturation Saturation The fraction or percentage of hydrocarbons remaining following the production of hydrocarbons from the reservoir. Residual_Hydrocarbon_Volume_Fraction Hydrocarbon_Volume_Fraction The volume fraction of residual hydrocarbons with respect to the total volume; residual hydrocarbons are those still in place in the flushed zone after the invasion process. Residual_Oil_Saturation Saturation The fraction or percentage of oil remaining following the liberation of gases from the reservoir. Residual_Water_Saturation Saturation The fraction or percentage of water remaining at maximum hydrocarbon saturation, as measured in core analysis. It differs from Irreducible_Water_Saturation because of filtrate invasion and gas expansion from the core being brought to the surface. Resistance Impedance The resistance of a medium to the flow of electric current; the real component of the complex quantity Impedance. Resistance_Gradient Gradient A measure of the change in electric resistance per unit length. Resistive_Inclusion_Contrast Conductivity_Contrast Conductivity contrast between resistive inclusions and the surrounding rock Resistive_Inclusion_Proportion Inclusion_Proportion Percentage of rock occupied by resistive inclusions within a given depth interval Resistive_Inclusion_Size Surface_Area Average area of resistive inclusions as seen at the borehole wall Resistivity Data_Valued_Property The property of a material which resists the flow of electrical current. The ratio of electric-field intensity to current density. The reciprocal of conductivity. Resistivity_Data_Density MWD_Data_Density Density of data samples per length of borehole traversed, for a resistivity logging measurement. Resistivity_Index Ratio The ratio of the resistivity of a formation to the resistivity it would have if 100% saturated with formation water (Rt/Ro). Resistivity_K_Factor Data_Valued_Property K Factor, a function of the geometry of the electrode or sensor array of a resistivity measurement device. Resistivity_Time_After_Bit Time_After_Bit In MWD/LWD logging, the time delay between the drill bit and a resistivity sensor reaching a given point in the wellbore. Resolution Multi_Use_Property The smallest separation between two objects such that they can still be discerned as separate objects. In sensor technology, the smallest change in input which will produce a detectable change in output. In this context, it is the same as Sensitivity. Resolution_Description Description Textual description of the qualified resolution, e.g., 0.005 psi at > 4 s sampling rate, 0.01 psi at 1 s sampling rate. Response_Equation Data_Valued_Property Sensor response equation Response_Frequency Frequency Instantaneous frequency at local maximum of reflection intensity Response_Parameter Multi_Use_Property Property which reflects the response of some measurement device or algorithm to a particular material or environment. The Unit_Quantity is determined by the type of measurement. Response_Phase Instantaneous_Phase Instantaneous phase at local maximum of reflection intensity Response_Strength Amplitude Reflection strength at local maximum of reflection intensity Restoring_Force Force The force required to restore initial conditions. For example, at the end of a test. Reynolds_Number Ratio The ratio of inertial force to viscous force for viscous fluid flow. Rheology_Model Type Mathematical model describing how the shear stress relates to the shear rate i.e. how a fluid flows and is deformed in response to applied stresses. Most popular model are Newtonian, Bingham Plastic and Power-Law Rheometer_Deviation Plane_Angle Vector of deviation angles of the rheometer related to the vector of given Angular Velocity Rig_Heading Azimuth Azimuth of the direction to which the rig is facing. Rig_Heave Height Amplitude of the vertical motion of the rig Rig_Pitch_Angle Plane_Angle Measure of the fore-aft rotational movement of the rig due the combined effects of wind and waves. Rig_Roll_Angle Plane_Angle Measure of the side-to-side rotational movement of the rig due the combined effects of wind and waves; measured as the angle from vertical. Right_Handed Flag Flag indicating that a 3D axis system is right-handed: a 3D coordinate system is Right_Handed if the direction of rotation from the x axis to the y axis is counter-clockwise when viewed from a positive position on the z axis. For example, if x is East and y is North, a Right_Handed system will have the positive z pointing upward (as increasing elevation). Right_Handed is meaningless for 2D systems. Right_Hidden_Width Width For core images, the width of the core which is hidden on the right side of the image (by core box, for example). Rights_Type Type Type of lease rights Rigid_Flag Flag Flag indicating that a piece of equipment is rigid. Riser_Angle Plane_Angle Angle of the marine riser with the vertical. Riser_Internal_Diameter Inside_Diameter The internal diameter of the marine riser. Riser_Tension Tension Tension of the marine riser Rock_Class Type Classification of rocks into Chemical, Volcaniclastic, etc. Rock_Code Code Catalog code of a rock type (e.g. Limestone) Rock_Compressibility Compressibility Compressibility of the rock matrix. Rock_Compressibility_Correlation Name Rock Compressibility Correlation (Sandstone, Carbonate) Rock_Compressibility_Depth Depth Measured depth for which Rock Compressibility is stated. Rock_Embedment_Strength Strength Force required to push a 1/8 inch diameter sphere 1/16 in into the rock. (Lab test). Value ranges from 5 to 20 kpsi for chalk, 40 to 100 kpsi for sandstones, 50 to 200 for Dolomites. Rock_Genesis Type Classification of rocks by genetic origin, e.g. Sedimentary, Igneous, etc. Rock_Solubility_In_Acid Solubility Amount of rock, normally expressed as a percentage by weight soluble in a given acid Rock_Solubility_In_HCl Rock_Solubility_In_Acid Amount of rock, normally expressed as a percentage by weight soluble in HCl Rock_Solubility_In_RMA Rock_Solubility_In_Acid Amount of rock, normally expressed as a percentage by weight soluble in Mud Acid (standard mixture of 12 % HCl and 3% HF) Rock_Subclass Type Classification of rocks into Carbonate, Evaporite, etc. Commonly called Lithology. Rotary_Speed Angular_Velocity Rotational speed of the Rotary Table. Rotating_Weight Hook_Load Surface weight of the drillstring while drilling Rotation Plane_Angle The angular displacement of a rotating body or figure. Rotation_1 Rotation Value of first rotation, as indicated by the first token in ROTATION_SENSE, used in transforming a coordinate system into a new (local) coordinate system. Rotation_2 Rotation Value of second rotation, as indicated by the second token in ROTATION_SENSE, used in transforming a coordinate system into a new (local) coordinate system. Rotation_3 Rotation Value of third rotation, as indicated by the third token in ROTATION_SENSE, used in transforming a coordinate system into a new (local) coordinate system. Rotation_Gradient Gradient A measure of the rotation of an object per unit length; e.g., flowmeter rotation per length of pipe, pipe rotation per unit length (for stuck pipe applications. Rotation_Sense Type Describes the sense of the axis system rotation specified by {ROTATION_1,ROTATION_2,ROTATION_3}. Most commonly used are "X_Y_Z" and "Z_NEWX_NEWZ". Rotor_Lobe_Count Count Number of rotor lobes in a drill motor configuration (PDM only). Note: Stator is equal to rotor plus one. Rotor_Number Ordinal_Number Number of the rotor. (For a cylindrical rheometer, each number corresponds to a different size. Standard Rotor is #1) Roundness Shape A measure of the degree of how round an object is, such as a contour on a Surface. Rover_Amplitude Amplitude Difference between seismic amplitude and the straight line connecting the two nearest extremes (with same kick). Royalty Money Royalty received by lessor Rugosity Shape A measure of surface irregularity, such as of the borehole wall. Run_Number Ordinal_Number The number (or rank) associated with a particular run of a tool or activity. Use is discouraged due to ambiguity when services are combined or when complete history unavailable; time of data acquisition is more reliable. Running_Direction Type Running direction of an equipment: Pulling Out Of Hole-POOH (Up=-1) or Running In Hole-RIH (Down=1) Running_Force Force The force needed to run. For example, during a test. Running_Length Length Sum of all the displacements in one direction (generally downhole) made by a downhole equipment. Used as fatigue indicator or charged item in coil tubing operations. Running_Speed Velocity Speed of an equipment running into (counted positive) or out of the hole (counted negative). SCAL_Flood_Direction Direction Direction of fluid flow through the sample in the laboratory (e.g. Horizontal, Downwards, Upwards). Water-oil experiments are almost always horizontal, gas-liquid experiments may be horizontal or vertical. If they are vertical they are done in the gravity stable direction. For example gas flooding an oil filled plug would be downwards, water flooding a gas filled plug would be upwards. SDM_Domain_Name Name Name of the data domain, as described in the Schlumberger Data Model. S_Wave_Angle Plane_Angle S-wave angle Safety_Drill_Type Type Type of Quality, Health, Safety, and Environmental safety drill such as Fire Drill, Abandon Ship Drill, Spill Control Drill. Safety_Factor Data_Valued_Property Amount by which some operating condition could be exceeded before reaching the theoretical operational limit, to allow for uncertainty in the actual upper limit. For upper limits, Operating Condition X (1 + Safety Factor) = Upper Limit. Sale_Date Date Date of lease purchase Sale_Group Type Within a business line, Sales services are gathered by group with technical commonalities. Sale_Number Identifier Sale number of lease purchase Salinity Chemical_Concentration Concentration of the total salts in solution (Na, K, Cl, So4, ..). Samarium_Yield Elemental_Yield Elemental contribution of Samarium with respect to total. Sample_Count Count Number of samples. Sample_Gas_Oil_Ratio Gas_Oil_Ratio Ratio of gas flowrate to oil flowrate when a sample is taken Sample_Interval Data_Valued_Property Index interval between sequential data samples; see also Depth_Increment and Time_Increment (Sampling_Period) Sample_Number Identifier The number assigned to a formation or fluid sample. Sample_Type Type Nature of the sample e.g. oil or gas Sample_Water_Oil_Ratio Water_Oil_Ratio Water oil ratio when a sample is taken Sampling_Bottle_Code Code Code for sampling bottle Sampling_Bottle_Number Identifier Sample bottle number Sampling_Bottle_Type Type Type of sampling bottle Sampling_Duration Time_Interval Duration of data sampling or recording. Sampling_End_Time End_Time End date/time of surface sampling Sampling_Period Time_Interval Time interval between the recording of two sequential data samples. Sampling_Start_Time Start_Date Starting date/time of surface sampling Sand_Concentration Solids_Concentration Sand content per Mud Volume, API RP13B, Section 5, Sand Sand_Volume_Fraction Volume_Fraction Volume fraction of sand as calculated, measured or inferred from formation properties. Sandface_Flowing_Pressure Pressure The pressure in the formation immediately prior to entering any completion pressure drops. Saturation Data_Valued_Property The fraction or percentage of the pore volume occupied by a specific fluid; e.g., oil, gas, water. Saturation_Exponent Exponent The exponent of the Saturation term in the Archie saturation equation. Abbreviated "n". Sayers_Anellipticity Coefficient Sayers' normalized anellipticity factor, an alternative to eta for describing the relationship between horizontal and moveout compressional velocities. Scale_Factor Coefficient Coefficient used to convert or correct data, as to some standard. Scale_Factor_Latitude Latitude Latitude at which scale factor is exact. Scale_Factor_Longitude Longitude Longitude at which scale factor is exact. Scale_X Scale_Factor Scale factor in X dimension Scale_Y Scale_Factor Scale factor in Y dimension Scale_Z Scale_Factor Scale factor in Z dimension Scan_Type Type Describes the way in which a subject is scanned to take data samples or to generate an image. Scheduled_Start_Time Start_Time Scheduled start time for an activity Schoenberg_Ellipticity Coefficient Schoenberg's ellipticity factor, the ratio of horizontal to vertical velocity Screen_Angle Inclination Angle of the screen, with respect to horizontal Screen_Arrangement Type Position of the screens, such as in a shale shaker. Screen_Count Count Number of Screens Screen_Mesh_Size Diameter Size of the mesh (usually expressed in inches) use to filter particles. Screen_Motion Type An indicator of the current state of the movement induced by the vibrator(s) of a shale shaker screen Screen_Tension_Type Type Type of screen tension (deck tensioned or factory pretensioned) Second_Derivative Gradient Gradient of gradient of a scalar function Secondary_Porosity Porosity The additional porosity created by chemical changes, specially fissures, fractures, solution vugs and dolomitization. Section_Length Length Length of one section, such as the nominal length of one section of a streamer. Section_Number Identifier Jeffersonian Section Number Section_Suffix Name A subsection single letter suffix designation a part of a Section, as used in California, USA Section_Type Type Jeffersonian Section Type such as a Lot Sediment_And_Water Ratio Measure of impurities which are contained in oil produced from a well, as described in ASTM Standard Test D96-82. Traditionally called Basic Sediment and Water. Sedimentary_Channel_Type Type The type of the sedimentary environment that created the channel, e.g. Submarine, Stream, Tidal, etc. Sedimentary_Feature_Type Type The type of the sedimentation feature associated with a subsurface or surface Earth region. Sedimentary_Structure_Type Type The type of sedimentary structure associated with an interval. Sedimentary_Unit_Type Type The type of sedimentary unit e.g. channel, bar, etc. Segment_Length Interval_Length The length of a borehole segment. Seismic_Arc_Length Acoustic_Amplitude A measure of reflection heterogeneity which is used to quantify lateral changes in reflection patterns. Used as a stratigraphic sequence indicator. Seismic_Flag Flag Flag indicating that the object or data pertains to seismic techniques or was derived from seismic data. Seismic_Object_Type Type Type of seismic data object: data or survey geometry, 2 or 3D Seismic_Offset Length The distance between source and receiver or geophone (seismic). Seismic_Vertical_Depth True_Vertical_Depth Vertical Depth from Seismic Reference Datum Semblance Coherence A measure of waveform coherence with respect to slowness and time, computed as a function of coherent energy to total energy; also called "Slowness_Time_Coherence" Semi_Major_Axis Radius Length of semi-major axis of an ellipse; in geodetic work, of a reference ellipsoid. Semi_Minor_Axis Radius Length of semi-minor axis of an ellipse; in geodetic work, of a reference ellipsoid. Sensitivity Multi_Use_Property The ratio of sensor or instrument output to input. Sensitivity_To_Temperature Sensitivity Sensitivity to temperature variation for a sensor Sensor_Azimuth Azimuth The azimuth of a sensor on a logging device, used to determine the orientation of the device. Sensor_Code Code Sensor code Sensor_End_Time End_Time End time (tend) as observed by downhole or surface sensors, measured as elapsed time since the Time Reference. Sensor_Number Ordinal_Number Sensor number Sensor_Standoff Standoff The distance from a sensor to the medium being investigated, such as from a logging sonde to the wall of the borehole. Sensor_Start_Time Start_Time Start time (t0) as observed by downhole or surface sensors, measured as elapsed time since the Time Reference. Sensor_Type Type Type of sensor used to acquire data Separator_Code Code Code for the separator Separator_Gas_Capacity Gas_Flowrate Gas separator capacity at maximum working pressure and 1 minute retention time at low liquid level (MMscf/day) Separator_Line Type Type of separator line: e.g. oil outlet, gas outlet, water outlet or inlet Separator_Liquid_Capacity Liquid_Flowrate Liquid separator capacity at maximum working pressure and 1 minute retention time at high liquid level Separator_Oil_Flowrate Oil_Flowrate Oil flowrate at separator conditions when a sample is taken Separator_Pressure Pressure Pressure of the separator when a sample is taken Separator_Temperature Temperature Temperature of the separator when a sample is taken Separator_Type Type Separator type Sequence_Boundary_Type Type The type of a Sequence Boundary in the Earth subsurface, e.g. Toplap, Concordance, Baselap, etc. Sequence_Lower_Limit_Type Type The type of surface situated at the base of a sequence. Sequence_Number Ordinal_Number Number used to identify or index an element in a sequence. Sequence_Order Type The order of a sequence in the depositional process. Sequence_Surface_Type Type The type of surface bounding a particular sequence. Sequence_Trend Type The type of vertical evolution recognized in a particular sequence e.g. fining up. Sequence_Type Type The type of sequence, e.g. granulometry, thickness, facies, etc. Sequence_Upper_Limit_Type Type The type of limit bounding the top of a sequence. Serial_Number Identifier The serial number placed on a piece of equipment. Service_Code Code MIS Code of the service and unique identifier. Service_Date Date The date on which a service was performed. Service_Type Type Type of service Session_Duration Duration Elapsed time from the start to the finish of a recording or processing session. Setting_Force Force Load which must be applied to set compression type packer. Typical value : 10,000 lbf Setting_Mode Type Mode for setting a plug or packer: by compression or inflation Setting_Tool Type Generic type of plug or packer setting tool: Drill-Pipe or Wireline Settled_Proppant_Height Height Height of the settled bank of proppant within a fracture, otherwise named pack height. Shale_Volume_Fraction Volume_Fraction Volume fraction of shale as calculated, measured or inferred from formation properties. Shallow_Conductivity Conductivity The conductivity which represents a measurement made approximately one to two feet into the formation; generally considered to measure the formation where it contains fluids which are comprised primarily of mud filtrate. Shallow_Induction_Conductivity Shallow_Conductivity The conductivity, measured by an induction log, which represents a measurement made approximately one to two feet into the formation; generally considered to measure the formation where it contains fluids which are comprised primarily of mud filtrate. Shallow_Induction_Resistivity Shallow_Resistivity The resistivity, measured by an induction log, which represents a measurement made approximately one to two feet into the formation; generally considered to measure the formation where it contains fluids which are comprised primarily of mud filtrate. Shallow_Lateral_Resistivity Shallow_Resistivity Resistivity measurement using a "lateral" electrode arrangement with a "shallow" investigation radius (several inches into the formation). Shallow_Laterolog_Conductivity Shallow_Conductivity The conductivity, measured by a laterolog (or guard log) resistivity device, which represents a measurement made approximately one to two feet into the formation; generally considered to measure the formation where it contains fluids which are comprised primarily of mud filtrate. Shallow_Laterolog_Resistivity Shallow_Resistivity The resistivity, measured by a laterolog (or guard log) resistivity device, which represents a measurement made approximately one to two feet into the formation; generally considered to measure the formation where it contains fluids which are comprised primarily of mud filtrate. Shallow_Normal_Resistivity Shallow_Resistivity Shallow Resistivity measurement using a "normal" electrode arrangement. Shallow_Resistivity Resistivity The resistivity which represents a measurement made approximately one to two feet into the formation; generally considered to measure the formation where it contains fluids which are comprised primarily of mud filtrate. Shank_Diameter Outside_Diameter Outer diameter of the equipment shank; for a drill bit, the shank is the portion of the bit body between the threaded connection and the base of the bit leg (for roller cone bits) or bit crown (for fixed cutter bits). Shank_Length Length Length of the equipment shank; for a drill bit, it is the distance from the face of the bit connection to the base of the bit leg (for roller cone bits) or bit crown (for fixed cutter bits). Shape Geometry A visible makeup characteristic of a particular item or kind of item. Also the spatial form of an item, or a standard or universally recognized spatial form. Shape_Code Array_Code Catalog-controlled code of an array Shape. Shape_Factor Geometrical_Factor A geometrical factor (Ca) characteristic of the reservoir areal drainage shape (e.g. circle or square) and the well location (e.g. centered). Shear_Compressional_Slowness_Ratio Ratio Ratio of shear slowness (Shear_Slowness) to compressional slowness (Compressional_Slowness). Shear_Compressional_Velocity_Ratio Ratio Ratio of velocity of Shear wave (Vs) to that of Compressional wave (Vp). Shear_Modulus Elastic_Modulus The stress-strain ratio for simple shear. Also called rigidity modulus or Lame's constant. Shear_Slowness Acoustic_Slowness Acoustic slowness of a shear wave (Vs); reciprocal of Shear_Velocity; a shear wave is a type of seismic wave in which the particle motion is perpendicular to the direction of propagation; also called S-wave or secondary wave. Shear_Strain Strain Shear component of the change in dimensions caused by stress, generally expressed as a unitless ratio. Shear_Stress Stress Shear force (shear: strain that causes contiguous parts of a body to slide relatively to each other in a direction parallel to their plane of contact) per area unit of surface Shear_Velocity Acoustic_Velocity The velocity of a shear wave (Vs); a shear wave is a type of seismic wave in which the particle motion is perpendicular to the direction of propagation; also called S-wave or secondary wave. Shear_Velocity_Gradient Gradient A measure of the change in the shear velocity of a medium per unit length. Shock_Level Indicator Qualitative indicator of Shock_Rate; used as a real-time indicator of vibration severity for MWD/LWD tools. Shock_Rate Frequency Measure of shocks or vibrations above some threshold per unit of time; used to quantify vibration severity for MWD/LWD tools. Short_Name Name Informal, usually shortened name given to an object or data item; a nickname. Shotsequence_Number Ordinal_Number Nominal ordering matching raw receiver sort Show_Description Description A textual description of the hydrocarbon shows in a rock sample. Show_Distribution Description A textual description of the distribution of hydrocarbon indicators on a rock surface; e.g. solid, spotty, streaky. Show_Flow_Rate Description A textual description of the rate at which fluid emerges from the rock sample. Example keywords include: dead oil, live show, streaming or bleeding. Show_Quality Description A qualitative indicator of the intensity of the fluid show. Show_Type Type The type of hydrocarbon show from a Well or from a Sample (Core, Cuttings, etc.): e.g. Gas, Oil, etc. Shrinkage_Factor Volume_Fraction A measure of the decrease in volume of the liquid phase caused by release of solution gas and/or by the thermal contraction of the liquid; the reciprocal of formation volume factor. Siderite_Volume_Fraction Volume_Fraction The volume fraction of siderite with respect to the total volume. Sidetrack_Number Identifier A sequential number identifying a particular sidetrack; 0 if no sidetracks have occurred. Used for WITS Channel SKNO. Signal_Amplitude Amplitude The amplitude associated with a generic type signal. Signal_To_Noise_Ratio Ratio The ratio of signal amplitude to noise amplitude, usually expressed in dB. Signal_Type Type Type of data signal. Silicon_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of silicon to total dry weight Silicon_Yield Elemental_Yield Elemental contribution of Silicon with respect to total. Silt_Volume_Fraction Volume_Fraction The volume fraction of silt with respect to the total volume. Simulation_Layer_Name Name Name given to a layer in a reservoir simulation model. Simulation_Multiple_Count Count Number of multiple reflections considered in the simulation Single_Shot_Flag Flag If flag is set, it means that the equipment or item can only be used once before rework or replacement. Skin_Factor Data_Valued_Property The term that accounts for additional pressure drops in the immediate vicinity of a well in well performance calculations. A positive skin indicates damaged conditions, negative indicates stimulated conditions. Slackoff_Friction_Coefficient Coulomb_Friction_Coefficient Friction coefficient between a string and the pipe when running into the hole Slackoff_Hook_Load Hook_Load Average slackoff hook load (slackoff weight) over the reporting period. Slackoff_Reel_Back_Tension Tension Amount of tension kept on the coiled tubing between the gooseneck and the reel while going into the hole Slant_Rig_Angle Plane_Angle Slant rig angle Slant_Rig_Flag Flag A flag indicating if the rig is slanted. Slew_Rate Data_Valued_Property Highest rate of change in signal level which a device can produce; also the rate at which a device reacts to commands. In the latter case, the data are normally represented in units of time. Sliding_Window_Duration Time_Interval Duration (length) in time of the sliding window used for processing. Slippage_Velocity Flow_Velocity In two-phase flow, the difference between the velocities of the two phases. Slope Multi_Use_Property The slope of a function: the tangent of the angle between the x-axis and the tangent to the curve defined by the function. Slot_Width Width Width of a slot, such as in a slotted liner. Slowness_Time_Coherence Coherence A measure of waveform coherence with respect to slowness and time, computed as a function of coherent energy to total energy; also called "Semblance" Small_Circle_Azimuth Azimuth The azimuth of the pole associated with a small circle. Small_Circle_Dip Dip_Angle The angle of the pole associated with a small circle. Smectite_Volume_Fraction Volume_Fraction The volume fraction of smectite with respect to the total volume. Smoothing_Mode Processing_Option Mode to use while smoothing horizon picks (automatic, manual). Snap_Criteria Data_Mask Set of parameters used by an application for "snapping" interpretation values to their corresponding data samples Snap_Depth_Window_Bottom Snap_Window_Bottom Distance below the picked Z to search for the Tracking Event and Snap_Type when snapping Snap_Depth_Window_Top Snap_Window_Top Distance above the picked Z to search for the Tracking Event and Snap_Type when snapping Snap_Quality Quality_Indicator Indicates whether the values are snapped to a sample or sub-sample Snap_Type Type When snapping to the Seismic Event Type the application should snap to the Largest or Closest (Valid only for peak or trough) Snap_Window_Bottom Offset Interval (time or depth) below the picked Z to search for the Tracking Event and Snap_Type when snapping Snap_Window_Top Offset Interval (time or depth) above the picked Z to search for the Tracking Event and Snap_Type when snapping Sodium_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of sodium to total dry weight Sodium_Yield Elemental_Yield Elemental contribution of Sodium with respect to total. Solids_Concentration Concentration Solid Concentration (Cutting, clays, polymer) per fluid Volume Solids_Control_Cone_Count Count Number of cones of a solid Control Equipment Solids_Control_Cone_Diameter Diameter Largest Inner Diameter of a Cone Solubility Data_Valued_Property A measure of the amount of one substance (the solute) which will dissolve in a given amount of another (the solvent). Solution_Gas_Liquid_Ratio Gas_Liquid_Ratio The ratio of dissolved gas volume to total liquid (oil + water) volume Solution_Gas_Oil_Ratio Gas_Oil_Ratio Measure of the degree to which a gas is soluble in oil; ratio of the dissolved gas volume to liquid hydrocarbon volume, often designated Rs Oil Solution_Gas_Oil_Ratio_Correlation Type Model used to compute gas solubility in oil Sonde_Error Error An unwanted portion of the total conductivity measurement of an induction logging instrument, generated by imperfections in the coils in the sonde. It is measured during surface calibration and then cancelled during the survey operation. Sonic_Data_Density MWD_Data_Density Density of data samples per length of borehole traversed, for a sonic logging measurement. Sonic_Porosity Apparent_Porosity Porosity calculated using the acoustic slowness measurement from a sonic log. Sonic_Porosity_Dolomite Sonic_Porosity Porosity calculated using the compressional wave travel time measurement from an acoustic log with a dolomite matrix travel time. Sonic_Porosity_Limestone Sonic_Porosity Porosity calculated using the compressional wave travel time measurement from an acoustic log with a limestone matrix travel time. Sonic_Porosity_Sandstone Sonic_Porosity Porosity calculated using the compressional wave travel time measurement from an acoustic log with a sandstone matrix travel time. Sonic_Time_After_Bit Time_After_Bit In MWD/LWD logging, the time delay between the drill bit and a sonic sensor reaching a given point in the wellbore. Source Data_Valued_Property The source of an entity instance, usually a user name or an application (or activity) instance. Source_Angle Plane_Angle Source angle Source_File File_Name File containing the original description of the object, e.g., TIF file for an image. Source_Line_Position Cylindrical_Position Position in a source line. Source_Line_Rho Radius Horizontal (x-y) distance from origin of position in a source line. Source_Line_Theta Theta_Angle Horizontal angle of position in a source line, measured counter-clockwise from x-axis. Source_Line_Z Z_Coordinate Z-coordinate of position in a source line. Source_Offset Seismic_Offset The distance to the seismic source from some other object, such as a wellbore in VSP work. Source_Orientation Spherical_Position Downhole source orientation vector. Source_Orientation_Phi Inclination Vertical angle of downhole source, measured from the x-y plane. Source_Orientation_Rho Radius Horizontal (x-y) distance from origin of downhole source. Source_Orientation_Theta Theta_Angle Horizontal angle of downhole source, measured counter-clockwise from x-axis. Spacing_X Interval_Length Spacing in X dimension; may be expressed as an absolute spacing with units or as a proportion of some reference X Spacing. Spacing_Y Interval_Length Spacing in Y dimension; may be expressed as an absolute spacing with units or as a proportion of some reference X Spacing. Spacing_Z Interval_Length Spacing in Z dimension; may be expressed as an absolute spacing with units or as a proportion of some reference X Spacing. Sparse_2D_Data Data_Valued_Property A data set of sparse location data in 2-space, where none or up to n Properties may be represented at each location. Example: X_Coordinate,Y_Coordinate,Porosity,Density. Sparse_3D_Data Data_Valued_Property A data set of sparse location data in 3-space, where none or up to n Properties may be represented at each location. Example: X_Coordinate,Y_Coordinate,Z_Coordinate,Velocity. Spatial_Gamma_Radiation_Intensity Gamma_Ray Intensity of gamma radiation represented as a function of a spatial path. Species Biological_Name A category of biological classification ranking immediately below the genus or subgenus. Specific_Gravity Density The ratio of the density of a substance to the density of some other substance taken as a standard (e.g. water, hydrogen). Specific_Heat Data_Valued_Property The amount of heat in calories required to raise the temperature of 1 gram of substance by 1 degree Celsius. Specific_Productivity_Index Mobility Rate of fluid produced per unit change in limiting pressure per unit of reservoir thickness. For oil wells, PIs is normally expressed in barrels per day per psi per foot of net reservoir thickness. Specific_Surface_Area_Per_Mass Data_Valued_Property The characteristic of a porous media which is the internal surface area of the medium per unit mass. Specific_Surface_Area_Per_Volume Data_Valued_Property The characteristic of a porous media which is the internal surface area of the medium per unit volume. Specific_Volume Data_Valued_Property A measure of the volume distribution of a gas or liquid per unit mass. Spectral_Fluorescence_Intensity Data_Valued_Property Intensity of light emitted by a material represented as a function of emitted light wavelength and wavelength of the excitation beam, typically an ultraviolet light source. Spectral_Gamma_Radiation_Intensity Gamma_Ray Intensity of gamma radiation represented as a function of wavelength. Spherical_Mobility Mobility A measure of the ease with which a fluid can be moved in a specific medium (i.e. rock); computed as the cube root of (Vertical_Mobility X Horizontal_Mobility**2) Spherical_Permeability Directional_Permeability An effective permeability used to combine directional permeabilities, Kx and Ky. Usually abbreviated as Ksph. Spherical_Position Location Set of coordinates specifying the position of a point in a spherical coordinate system Spherically_Focused_Conductivity Shallow_Conductivity The conductivity, measured by a spherically focused log, which represents the resistivity approximately one to two feet into the formation. Spherically_Focused_Resistivity Shallow_Resistivity The resistivity, measured by a spherically focused log, which represents the resistivity approximately one to two feet into the formation. Sphericity Shape A measure of the degree of how spherical an object is, such as an Lens within a subsurface Volume Spinner_Speed Angular_Velocity Rotational speed of the flowmeter spinner. Spliced Modifier The data related to the property has been obtained by concatenating two or more other data sources. Spontaneous_Potential Electric_Potential The potential difference (DC voltage) between a movable electrode in the borehole and a distant reference electrode usually at surface. The voltage is due to currents generated by the Electrochemical and Electrokinetic potentials. Spontaneous_Potential_Drift Gradient The drift in the measured Spontaneous Potential per depth. Spore_Color_Index Color Relative color of fossil spores as caused by thermal processes. Index is used as an indicator of thermal maturation of organic material. Spot_Description Description The fractional part of interest within the section Spring_Number Ordinal_Number Spring number of a cylindrical rheometer corresponding to a particular stiffness. Fann 35 spr #1stiffness is 2.2116E-3 Nm/Rad Spring_Stiffness Data_Valued_Property Coefficient relating spiral spring exerted force and corresponding elongation Spud_Date Date The date a spud attempt was performed on a well Spurt Length (Fracturing) Volume of fluid flowing through a given area of porous media which leaks off during the formation of the filter cake. Spurt loss reduces the fluid volume available for fracture extension. Typical Unit: gal/100ft2. Squared Modifier The data related to the property is the result of a squaring process, i.e., a process that converts a smooth function into a step function. Stab_To_Bottom_Conn_1 Length Length from the mid-point of the first stabilizer to the bottom connection of the tool Stab_To_Bottom_Conn_2 Length Length from the mid-point of the second stabilizer to the bottom connection of the tool Stab_To_Bottom_Conn_3 Length Length from the mid-point of the third stabilizer to the bottom connection of the tool Stable_Elapsed_Time Time_Interval Time elapsed since production conditions were stable Stack_Alkhalifah_Eta Alkhalifah_Eta Effective value through the subsurface of Alkhalifah's eta anisotropy parameter. Stack_Anisotropic_Axis_1_Crossline_Direction Anisotropic_Axis_1_Crossline_Direction Estimation of the anisotropic axis 1 crossline direction for all layers to the current depth. Stack_Anisotropic_Axis_1_Inline_Direction Anisotropic_Axis_1_Inline_Direction Estimation of the anisotropic axis 1 inline direction for all layers to the current depth. Stack_Anisotropic_Axis_2_Crossline_Direction Anisotropic_Axis_2_Crossline_Direction Estimation of the anisotropic axis 2 crossline direction for all layers to the current depth. Stack_Anisotropic_Axis_2_Inline_Direction Anisotropic_Axis_2_Inline_Direction Estimation of the anisotropic axis 2 inline direction for all layers to the current depth. Stack_Bale_Kappa Bale_Kappa Effective value through the subsurface of Bale's kappa, the mode-converted wave equivalent to eta, describing the relationship between horizontal and moveout mode-converted wave velocities. Stack_Bale_Xi Bale_Xi Effective value through the subsurface of Bale's xi, the shear wave equivalent to eta, describing the relationship between horizontal and moveout shear wave velocities. Stack_Crossline_Dip Crossline_Dip Estimation of the crossline dip for all layers to the current depth. Stack_Inline_Dip Inline_Dip Estimation of the inline dip for all layers to the current depth. Stack_Mode_Converted_Velocity Mode_Converted_Velocity Stacking converted-wave velocity, for a wave traveling through layers as a Compressional wave in one direction and a Shear wave in the other. This can be computed from a combined RMS average of the Compressional and Shear interval velocities. In practice it is usually determined directly from velocity analysis on short offset converted wave data. Stack_Number Ordinal_Number Stack number Stack_Polarization_Azimuth Polarization_Azimuth Estimation of the polarization azimuth angle for all layers to the current dept. Stack_Sayers_Anellipticity Sayers_Anellipticity Effective value through the subsurface of Sayers' normalized anellipticity factor. Stack_Schoenberg_Ellipticity Schoenberg_Ellipticity Effective value through the subsurface of Schoenberg's ellipticity factor, for each layer. Stack_Shear_Velocity Shear_Velocity Stacking shear wave velocity computed from an RMS average of the Shear interval velocities. In practice it is often determined from velocity analysis on Shear wave data, or indirectly from the stacking velocities for Compressional and Converted wave data. Stack_Thomsen_Delta Thomsen_Delta Effective value through the subsurface of Thomsen's delta anisotropy parameter. Stack_Thomsen_Epsilon Thomsen_Epsilon Effective value through the subsurface of Thomsen's epsilon anisotropy parameter. Stack_Thomsen_Gamma Thomsen_Gamma Effective value through the subsurface of Thomsen's gamma anisotropy parameter. Stack_Thomsen_Sigma Thomsen_Sigma Effective value through the subsurface of Thomsen's sigma anisotropy parameter Stack_Velocity Acoustic_Velocity The velocity determined from velocity analysis based upon normal-moveout measurements. Stack_Velocity_Ellipticity_Azimuth Velocity_Ellipticity_Azimuth Estimation of the velocity ellipticity azimuth for all layers to the current depth. Stack_Velocity_Ellipticity_Flattening Velocity_Ellipticity_Flattening Estimation of the velocity ellipticity flattening for all layers to the current depth. Stacked Modifier The data related to the property is the sum of two or more other data sources. Stacked_Time_Interpretation Time_Interpretation Seismic traveltime interpretation based on stacked seismic sections Stacking_Method_Type Method_Type Stacking method (e.g. median, average, auto, manual) Stage_Count Count Number of stages in an activity. Stage_Volume Volume Volume of material pumped during a stage of an activity. Standard_Deviation Statistical_Property Statistical standard deviation from the mean value for some data; normally abbreviated a lowercase sigma; the unit quantity is determined by that of the data. Standard_Document_Identifier Identifier Standard document identifier, such as an ISBN or ISSN number. Standard_Oil_Flowrate Oil_Flowrate Oil flow rate at standard condition when a sample is taken Standard_Pressure Pressure Pressure considered to be "standard", for rates and volumes reported to be measured at Standard Conditions. Standard_Reference_Datum Depth Depth measured from the Standard Reference Datum Standard_Temperature Temperature Temperature considered to be "standard", for rates and volumes reported to be measured at Standard Conditions. Standing_Oil_Flag Flag Indicates if there is standing, motionless oil Standing_Water_Flag Flag Indicates if there is standing, motionless water Standoff Length The amount of physical separation between two objects, usually maintained in order to control their interaction. Standoff_Porosity Apparent_Porosity Porosity measurement of the "standoff" region, a very shallow porosity determination used to correct formation porosity measurements from nuclear logging tools. Standoff_Ratio Standoff A measure of standoff of tubular equipment from the borehole wall, computed as the ratio of Standoff to the difference between hole radius and tubular radius; Standoff Ratio is 0 if the tubular is in contact with the hole wall, 1 if the tubular is centered in the hole. Standpipe_Pressure Pressure Mud pressure at the stand pipe manifold, just before the flexhose connecting to the swivel. Start_Age Geologic_Age The earliest (numerically largest) geologic or geochronologic age associated with an event or item, such as an earth layer, a fossil or pollen type. Start_Age_Code Geologic_Age_Code The code of the earliest geologic or geochronologic age associated with an event or item, such as an earth layer, a fossil or pollen type. Start_Date Date The date/time a particular activity started. Start_Depth Depth Depth at which an activity starts e.g. at the beginning of the Coiled tubing pumping stage, depth of the cleaning tool Start_Time Absolute_Time The time a certain activity or sub-activity started. Use Start_Age for geochronological time. Starting_Force Force The force applied at the start of a process. For example, at the beginning of a test. State_Code Geopolitical_Region_Code Catalog-controlled code of a State State_Name Name Name of a State Static_Potential Pressure Static (built up) pressure of a hydraulic unit, converted to pressure potential at a reference datum depth. Static_Pressure Pressure Static (non-flowing) Pressure Static_Pressure_Date Date Date when Static Pressure data were recorded Station_Inflection Flag Logical flag for each seismic station indicating whether or not it is an inflection point Station_Number Ordinal_Number Depth identifier Station_Residual_Static Data_Valued_Property Residual static information (time) for each station Statistical Modifier A Modifier of a property which is derived from the statistical analysis of, and which is used to characterize, another property. Statistical_Property Data_Valued_Property A property of statistical nature, e.g. Standard Deviation, Average or Mean, Median, etc. Statistical_Skewness Statistical_Property A statistical measure of asymmetry in a distribution. Status Indicator An indicator of the state of an entity or process at some moment in time. Also the position or rank in relation to others. Std_Parallel Latitude Latitude of parallel along which scale is true. Std_Parallel_1 Latitude First line of latitude along which scale is true, for map projections using two standard parallels; this parallel is NEAREST to the EQUATOR. Std_Parallel_2 Latitude Second line of latitude along which scale is true, for map projections using two standard parallels; this parallel is NEAREST to the POLE. Steel_Grade Grade Grade used to qualify the characteristics of the steel. For tubulars, grade determines the minimum yield strength and thus the burst and collapse pressures and is of importance for the proper choice of slips. The grade can be either custom, i.e. defined by the supplier, e.g. US Steel FS80, Vallourec 110 VS 22, or defined by the API, e.g. C75, J55, N80, E. Number in the API grade means the minimum yield strength in kpsi (N80: 80,000 psi). API grades for Tubing, Casing and Drill pipes can be found in the API specifications 5xx. Stiffness Data_Valued_Property The ratio of stress acting in a specified direction to the strain in a specified direction. Stiffness is a tensor of rank 4, but is expressible as a 6x6 matrix, the inverse of the compliance matrix. Stoneley_Slowness Acoustic_Slowness The acoustic slowness of a Stoneley wave; a Stoneley wave is a type of seismic wave which is propagated along an interface, such as a tube wave in a borehole. Stoneley_Velocity Acoustic_Velocity The velocity of a Stoneley wave; a Stoneley wave is a type of seismic wave which is propagated along an interface, such as a tube wave in a borehole. Stop_Date Date The date a particular activity stopped. Stop_Depth Depth Depth at which a particular activity stopped. Stop_Time Absolute_Time The time a certain activity or sub-activity stopped. Storage_Capacity Volume_Fraction The ratio of the sum of layer porosity thicknesses to total system porosity thicknesses for layered porous media. Storage_Label Identifier Label found on any stored item, such as tapes, documents, etc. Storage_Location Location The name of the location where an item is physically stored. Storativity Data_Valued_Property Product of Porosity and Total Compressibility for a reservoir hydraulic unit. Storativity_Ratio Ratio Ratio of component storativity to total system storativity. Usually known as Omega in reservoir dynamics. Storativity_Thickness Data_Valued_Property The product of the Storativity of a layer and its thickness [phi*Ct*h]. Storativity_Thickness_Ratio Ratio Ratio of component storativity-thickness to total system storativity-thickness [phi*Ct*h(i) / phi*Ct*h(total)]. Strain Data_Valued_Property Measure of the change in dimensions or shape caused by stress, generally expressed as a unitless ratio of the change of length per unit of initial length. If not otherwise specified, strain is taken to be "normal" (in the same direction as the stress). Streamer_Length Length The nominal length of the streamer. Street_Address Address Physical location of a business, residence, or other installation, as would be used by a courier service or visitor to locate the installation. Strength Pressure A measure of the ability of a body to resist applied force. Stress Data_Valued_Property Force acting per unit area in a material resisting the stretching, compression or shear induced by external forces; fully characterized by a Stress_Tensor. Stress_Gradient Gradient Change in stress magnitude over distance. Stress_Tensor Stress A second rank tensor whose components are the stresses exerted across surfaces perpendicular to the coordinate directions. Stretch Length The amount of elongation observed in an object as a result of its being placed under tension. Stretch_Coefficient Indicator The amount of stretch per unit force applied. Stripper_Friction_Load Load Amount of friction between the coiled tubing and the packoff assembly. It is not the hydraulic pressure within the Stripper. Stroke_Count Count Cumulative number of strokes over a time interval Stroke_Length Length Length of stroke (maximum travel), such as for a pump piston or for hydraulic jars). Stroke_Rate Count_Rate Frequency of the piston (plunger) of a pump usually expressed in number of strokes per minute Stroke_Volume Volume Volume of a pump stroke Strontium_Yield Elemental_Yield Elemental contribution of Strontium with respect to total. Structural_Dip_Removal_Flag Processing_Option This property specifies whether the effect of structural dipping on a particular geological zone has been removed. Structural_Dip_Type Type This property specifies whether the structural dip is constant, variable or contemporaneous. Structural_Model_Type Type Structural hypothesis chosen to derive the cross section Subgenus Biological_Name A category in biological taxonomy below a genus and above a species. Subsea_Equipment_Type Type Type of subsea equipment installed in facility or used in activity. Subsea_Vertical_Depth True_Vertical_Depth Vertical Depth from Mean Sea Level Sulfur_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of sulfur to total dry weight Sulfur_Yield Elemental_Yield Elemental contribution of Sulfur with respect to total. Sum_Amplitude Amplitude Sum of the amplitudes Sum_Magnitude Magnitude Sum of magnitudes Sum_Negative_Amplitude Sum_Amplitude Sum of amplitudes less than zero. Sum_Positive_Amplitude Sum_Amplitude Sum of amplitudes greater than zero. Summed_Traces_Number Count Number of traces in stack Super_Array_Code Array_Code Code of super array Supervised_Flag Flag Flag indicating whether the activity was supervised (1) or unsupervised (0) Supplier Organization_Name Supplier name of a Product. Surface_Area Data_Valued_Property Measure of the two-dimensional extent of the surface of some object. Surface_Cable_Tension Tension Tension of the logging cable as measured at the surface. Surface_Gas_Flowrate Gas_Flowrate Gas flowrate (surface conditions) Surface_Lines_Volume Volume Total volume of the surface lines equipment Surface_Location Location The location of a well, region, or facility/measurement point at the surface of the Earth. Surface_Oil_Flowrate Oil_Flowrate Oil flowrate (surface conditions) Surface_Reflection_Coefficient Reflection_Coefficient Reflection coefficient for the case when the multiples are reflecting from the free surface Surface_Sensor_Code Code Specific code of surface sensor. Surface_Sensor_Type Sensor_Type Type of surface sensor such as depth sensor, hydraulics depth sensor, kelly revolution sensor, etc. Surface_Surface_Intersection_Type Type The type of Surface-Surface intersection showing the types of the 2 intersecting surfaces. Surface_Temperature Temperature Temperature above ground. Temperature of the atmosphere. Surface_Type Type The type of an Earth surface in the subsurface Earth structure, e.g. Fault, Horizon, Boundary, etc. Surface_Water_Flowrate Water_Flowrate Water flowrate (surface conditions) Survey_Bearing Plane_Angle The horizontal angle of an object, measured as a departure from some datum direction, such as North or South. Representations typically indicate the datum and the direction of measurement, such as [N 26.46(deg) W]. Survey_Bottom_Depth Bottom_Depth Deepest depth to which the borehole was surveyed Survey_East_West Type Indicates whether survey location is East or West of reference line, such as principal meridian. Survey_North_South Type Indicates whether survey location is North or South of reference line, such as survey baseline. Survey_Top_Depth Top_Depth Shallowest depth of the survey or suite of surveys. Survey_Type Type Type of survey, such as one performed on a Well, e.g., Check Shot or Deviation Survey, or on a Region, Land or Marine, , e.g., Seismic survey. Synthetic_Seismic_Section Data_Valued_Property An artificial seismic section produced by collecting artificially-generated traces (such as a Synthetic_Seismogram from log-derived Reflectivity) or by extracting data from an actual seismic section. Synthetic_Seismogram Data_Valued_Property An artificial seismic reflection record produced by assuming a particular wavelet and model. Commonly, a one dimensional synthetic seismogram is generated by convolving a typical seismic wavelet with log-derived Reflectivity. Sys_Copy_Number Sequence_Number Number used to identify an instance of a particular type object within a set; used in conjunction with Copy_Number in GeoFrame. System_Identifier Identifier Identifier of a computer system. TBG_Grade_Bearing Drill_Bit_Grade_TBG TBG Drill Bit Grade based on bearing condition. TBG_Grade_Broken_Teeth Drill_Bit_Grade_TBG TBG Drill Bit Grade based on broken teeth TBG_Grade_Gauge Drill_Bit_Grade_TBG TBG Drill Bit Grade based on gauge. TBG_Grade_Gauge_OH Drill_Bit_Grade_TBG TBG Drill Bit Grade based on gauge out of hole. TBG_Grade_Tooth_Grade Drill_Bit_Grade_TBG TBG Drill Bit Grade based on teeth condition. TVD_Computation_Method Method_Type Method of defining the wellbore trajectory based upon directional survey data; includes curve fitting to the survey points and extrapolating beyond them. Table_Name Name Name of a database Table. Tank_Code Code Code for the tank Tank_Type Type Tank type Tape_Density Data_Valued_Property Tape density, usually expressed in bits per inch. Tar_Volume_Fraction Volume_Fraction The volume fraction of tar with respect to the total volume. Tectonic_Cycle_Type Type The type of tectonic cycle, i.e. distensive or compressive. Tectonic_Feature_Type Type The type of tectonic environment associated with an Earth subsurface, e.g. Fault, Fold, etc. Temperature Data_Valued_Property The degree of hotness or coldness measured on a definite scale Temperature_Accuracy Accuracy The maximum difference, over the calibrated range, between temperature applied to the gauge, with a reference standard, and the temperature measured by the gauge. Temperature_Data_Density MWD_Data_Density Density of data samples per length of borehole traversed, for an temperature measurement. Temperature_In Temperature The temperature of the input material. Temperature_Measure_Point Measure_Point_Offset The distance from the bottom of the Equipment to the point where the Temperature is measured Temperature_Out Temperature The temperature of the output material Temperature_Sensor_Code Code Temperature sensor code Temperature_Sensor_Resolution Temperature The minimum significant temperature change that can be detected above the noise. This is measured as the standard deviation of the differences between two successive measurements. Temperature_Sensor_Type Sensor_Type Type of temperature sensor Tensile_Yield Tension Maximum force which can be applied to an object without causing permanent deformation. Tension Force The force tending to cause extension of a body, as experienced in a cable, rope, string, etc. Term Duration Term of an agreement. Usually in years Terminal_Mode_Flag Flag Flag indicating whether or not the setup was filled in terminal mode (e.g. via an HP hand calculator). This affects the interpretation of the Job_Duration parameter. Termination_Date Date The date on which a lease, an organization, or any legal or organizational entity was terminated. Test_Code Code Catalog-controlled code of test type or analysis method. Test_Date Date The date at which a particular test activity was conducted. Test_Depth Depth Depth at which a formation test is performed; normally taken to be measured depth. Test_Number Ordinal_Number The number (or rank) associated with a particular test activity. Test_Pressure Pressure Recommended pressure at which the equipment is tested when inspected or certified Tetrahedron_Code Code Mineral tetrahedron name, e.g. Pettijohn Text Description Textual body a document or document section, such as a contract clause. Text_Location Location Location of a section of text, such as a contract clause; typical locations are paragraph number or line number on a page. Theoretical Modifier Confined to theory or speculation. Thermal_Alteration_Index Indicator An indicator of the thermal maturity of organic matter, based on a relationship between color of organic particles and the length and intensity of heat exposure. Thermal_Conductivity Data_Valued_Property Heat flux or thermal energy per unit length and temperature. The capacity of a body to conduct or pass thermal energy. The capacity of a material to conduct or pass thermal energy. Thermal_Gradient Gradient The rate of change of temperature with length. Thermal_Neutron_Decay_Time Time The time for the neutron population to fall to 1/e (37%) of its original value. Commonly called Tau, it is inversely related to Neutron_Capture_Cross_Section Thermal_Neutron_Near_Far_Ratio Ratio Ratio of the count rate of the near detector to that of the far detector in a thermal neutron logging device Thermal_Neutron_Porosity Neutron_Porosity Porosity as measured with a thermal neutron logging device. Theta_Angle Plane_Angle The horizontal angle measured counterclockwise from the x-axis. Thickness Length The smallest of three dimensions {length, width, and thickness} Thickness_Loss Thickness Loss of thickness due to any action such as corrosion or erosion Thin_Out_Azimuth Azimuth Azimuth of the thin out of a barrier type depositional environment. Third_Party_Certification Data_Valued_Property Certification by third party for the sampling bottle Thomsen_Delta Anisotropy Thomsen's delta anisotropy parameter, describing the relationship between vertical and moveout Compressional velocities. Thomsen_Epsilon Anisotropy Thomsen's epsilon anisotropy parameter, describing the relationship between vertical and horizontal Compressional velocities. Thomsen_Gamma Anisotropy Thomsen's gamma anisotropy parameter, describing the relationship between Horizontally polarized Shear (SH) velocities in the vertical and horizontal directions. Thomsen_Sigma Anisotropy Thomsen's sigma anisotropy parameter, describing the relationship between Vertically polarized Shear (SV) velocities in the vertical direction and moveout SV velocity. Thorium_Concentration Concentration Concentration of Thorium by weight Thorium_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of thorium to total dry weight Thorium_Potassium_Ratio Ratio Ratio of concentration of Thorium to that of Potassium. Thorium_Uranium_Ratio Ratio Ratio of concentration of Thorium to that of Uranium. Thorium_Yield Elemental_Yield Elemental contribution of Thorium with respect to total. Thread_Type Type Type of thread for casing pipe (such as short, long, buttress, extreme line) Threshold Multi_Use_Property The value of a property which signals some change in state or behavior of a material, process or algorithm. Threshold_Ratio Ratio Relative measure of trace value attribute; ratio of number of samples with values greater than threshold to total number of samples. Throughput Data_Valued_Property A measure of the mass produced, say from some facility, per unit time. Tie_Point_Phase_Shift Phase_Shift Phase difference between traces of seismic lines at a tie point. Tie_Point_Time_Quality Correlation_Coefficient Measure of the significance of a mis-tie computed on a correlation basis. Tie_Point_Total_Time_Correction Time_Interval Total amount of mis-tie correction to apply. Evaluated at line ties. Time Data_Valued_Property 1) The measured or measurable period during which an action, process, or condition exists or continues. 2) The point or period when something occurs. 3) A fixed moment or hour for something to happen, begin, or end. 4) A historical period. Time_After_Bit Delay_Time In MWD/LWD logging, the time delay between the drill bit and a sensor reaching a given point in the wellbore. Time_Dip Dip_Angle Dip computed on a time surface by measuring the difference in seismic times between two points compared to the horizontal distance between the points. Time_Increment Time_Interval Time increment between samples indexed by time. Time_Interpretation Two_Way_Time Generic interpretation on seismic traveltime sections Time_Interval Time A time value which is intended to indicate the duration of a process or event. Time_Of_First_Data Time_Interval Listening time until first detection Time_Pick Transit_Time Acoustic transit time (normally a two-way time) from seismic reference datum to the well marker, as picked from a seismic section. Time_Stamp Absolute_Time A time value which is associated with some event to fix its occurrence in time; often expressed as an elapsed time from recent reference time. Time_System_Offset_Wrt_Standard_Time Time_Interval Time zone correction (defined to fractions of an hour) to be added to vehicle system time to correct to standard time. (GMT, UTC,...) Time_Uncertainty Uncertainty Uncertainty of a time measurement. Time_Unit Unit_Code Unit for Time data Titanium_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of titanium to total dry weight Titanium_Yield Elemental_Yield Elemental contribution of Titanium with respect to total. Title Name A formal descriptive name, such as for a publication; also used for the role of person in an organization. To_Conn_Number Identifier Indicates which end or connection number (1 or 2 for tubulars, 3 for a hydraulic T,...) of the "To" equipment in a From_To equipment connection. The description of the "To" connection number is needed in some cases for equipment item which is last in the connection chain. When no ambiguity exists, the From_Conn_Number is the preferred property. To_Datum_Code Geodetic_Datum_Code Code of the target datum used in a datum-to-datum coordinate system transformation (datum shift). To_Entity_Code Entity_Code Code of Entity to which the relationship points To_Property_Code Property_Code Code of Property of Entity to which the relationship points Tolerance Statistical_Property Allowable uncertainty or deviation from a standard; the unit quantity is determined by that of the data value. Tool_Azimuth Azimuth Angle measured clockwise from North to the horizontal projection of the radius passing through the tool angle reference point. One of Tool_Azimuth or Relative_Bearing must be present Tool_Deviation Deviation Angle between the tool axis and the vertical. Tool_Measure_Point_Offset Measure_Point_Offset Distance from the Measure Point to the Tool Reference Plane (most often the bottom tool make-up plane); a positive value indicates that the Measure Point is above the Reference Plane. [Traditionally stored in Parameter MPOI on LIS/DLIS tapes.] Tool_Number Identifier Acquisition system tool number Tool_Rotation_Speed Angular_Velocity Rotational speed of the logging tool Tool_Speed Velocity Speed of the tool; logging speed. Tool_Status Status Indicator of some condition in the operation of a tool. Tool_String_Measure_Point_Offset Measure_Point_Offset Distance from the Measure Point to the Tool String (not just Tool!) Reference Plane; a positive value indicates that the Measure Point is above the Reference Plane. [Traditionally referred to as "tool zero".] Tool_Temperature Temperature Internal temperature of the logging tool Tool_Type Type The type of a Tool usually used in some activity, e.g. CNTA, USIT, AIT, etc. Toolface Plane_Angle In directional drilling, the angle between a reference direction on the drill string and a fixed reference, measured in a plane normal to the drillstring. In near-vertical applications, North is the fixed reference (Magnetic_Toolface); for higher deviation applications, Top of Hole is the reference (Gravity_Toolface). Toolface_Data_Density MWD_Data_Density Density of data samples per length of borehole traversed, for a toolface measurement. Toolface_Time_After_Bit Time_After_Bit In MWD/LWD logging, the time delay between the drill bit and the point at which the toolface measurement is taken reaching a given point in the wellbore. Top_Charge_Offset Length Distance from the bottom (make-up plane) of the gun or the assembly of guns to the upper perforating charge Top_Depth Depth The top depth of a borehole interval, a formation or any depth indexed representation of an data item. Top_Dip_Number Dip_Number Number of Dip (in the Dip Set) at the top of the Bed Top_Discontinuity_Type Discontinuity_Type Type of Discontinuity forming the top boundary Top_Location Location The location of the top of any Entity with a geometric extent (e.g., Zone Interval, Borehole, Borehole Segment, Rig, Arc, Edge, etc.). It is represented by some position relative to a coordinate system. Top_Subsea_Vertical_Depth Subsea_Vertical_Depth Subsea Vertical Depth of Top of Interval Top_True_Stratigraphic_Thickness_Depth True_Stratigraphic_Thickness_Depth True Stratigraphic Thickness Depth of Top of Interval Top_True_Vertical_Depth True_Vertical_Depth True Vertical Depth of Top of Interval Top_True_Vertical_Thickness_Depth True_Vertical_Thickness_Depth True Vertical Thickness Depth of Top of Interval Top_Two_Way_Time Two_Way_Time Depth of Top of Interval in Two Way Time Top_Value Multi_Use_Property Value at the top of an interval. Top_Vertical_Section Vertical_Section Top "depth" of an interval along a Vertical Section (VSCT) index. Torque Data_Valued_Property Something that produces rotation or torsion and whose effectiveness is measured by the product of the force and the perpendicular distance from the line of action of the force to the axis of rotation. Torsional_Yield Torque Maximum torque which can be applied to an object without causing permanent deformation. Tortuosity Shape A characteristic of permeable media that is the squared ratio of the mean flow path length to the medium length. Total Modifier Comprising or constituting a whole. Total_Compressibility Compressibility Compressibility of the rock matrix combined with fluid compressibilities within the matrix. Total_Depth Depth The total depth, usually of the well borehole. Total_Depth_Date Date The date/time at which the drilling reached total depth. Total_Flow_Area Surface_Area Total cross-sectional area through which fluid can flow. Total_Flowrate Flowrate Sum of the flowrates coming from different sources Total_Formation_Volume_Factor Formation_Volume_Factor Ratio of fluid volume (liquid + total solution gas) at specified (typically, reservoir) conditions to the volume of liquid and residual solution gas at surface (stock tank) conditions. Used for two-phase systems; abbreviated Bt; typical range 1.1 - 200. Total_Geometric_Spreading Coefficient The total effect of geometric spreading along ray. Factor giving the reduction in seismic amplitude (<1) due to spreading of the wave between two points. Includes both spherical divergence and cylindrical divergence. Total_Hardness Chemical_Concentration Sum of Ca and Mg concentration in water, API RP13B, Section 8, Water Based Mud, expressed as being entirely composed of calcium Total_Organic_Carbon Volume_Fraction Volume concentration of organic carbon relative to the total volume. Total_Organic_Matter Volume_Fraction Relative content of organic matter in a material, such as a rock sample. Calculated as total organic Carbon * 1.22. Total_Permeability_Thickness Permeability_Thickness Total permeability-thickness [= kh(1) + kh(2)] for a vertical interference test Total_Porosity Porosity The total volume fraction of a rock which is occupied by fluid; includes all forms of porosity, including that occupied by bound fluids, and is independent of rock and fluid materials and of environmental effects Total_Skin Skin_Factor The sum of all formation, completion, deviation, geometric and fluid flow skin factors. It can be a function of the flowrate if a Non-Darcy skin effect is present. Total_Storativity_Thickness Storativity_Thickness Sum of the Storativity_Thickness values of all layers in the model. Township_Number Identifier Jeffersonian Township Number Trace_Aperture Width The size of the aperture of the trace on the borehole surface Trace_Azimuth Azimuth The Azimuth coordinate of a trace Trace_Count_Receiver Count The maximum number of traces which were recorded at any individual receiver for all source events Trace_Count_Source Count The maximum number of traces assigned to the source Trace_Depth Depth The depth coordinate of a trace Trace_Elements Description Description of the trace elements in a sample or material. Trace_Length Length Length of a trace or mark which is visible on some surface, such as that of a road on a map, or of a fracture on a borehole wall. Tracking_Depth_Operator_Length Tracking_Operator_Length Length of the cross correlation window to use while tracking Tracking_Depth_Window_Bottom Tracking_Window_Bottom Distance below the picked Z to search for the Event_Type and Snap_Type while tracking Tracking_Depth_Window_Top Tracking_Window_Top Distance above the picked Z to search for the Tracking Event and Snap_Type while tracking Tracking_Operator_Length Time_Interval Length (time or depth interval) of the crosscorrelation window to use while tracking Tracking_Quality Quality_Indicator The acceptable value of the crosscorrelation for continued tracking (0.0 - 1.0). Tracking_Window_Bottom Offset Interval (time or depth) below the picked Z to search for the Tracking Event and Snap_Type while tracking Tracking_Window_Top Offset Interval (time or depth) above the picked Z to search for the Tracking Event and Snap_Type while tracking Trade_Name Name An arbitrarily adopted name that is given by a manufacturer or merchant to an article or service to distinguish it as produced or sold by him and that may be used and protected as a trademark. Trajectory Data_Valued_Property A description of the path that some activity or object makes as it traverses a medium. Transfer_Duration Time_Interval Duration of sampling operation Transfer_Fluid_Type Fluid_Type Liquid displaced away during sampling Transient_End_Time End_Time End time (tend) of the Transient Transient_Final_Flowrate Flowrate Flowrate at Transient End Time (qend) Transient_Final_Pressure Pressure Pressure at Transient End Time (pend) Transient_Initial_Flowrate Flowrate Flowrate at start of Transient Transient_Initial_Pressure Pressure Pressure at start of Transient Transient_Start_Time Start_Time Start time (t0) of the Transient Transit_Time Time_Interval Time required for a wave to travel from one point to another. Transit_Time_Accuracy Accuracy The accuracy attached to the transit time measurement or computation. Transit_Time_Ampmod Transit_Time Transit time estimated from processing Transit_Time_Initial Transit_Time Initial transit time Transit_Time_NMO Transit_Time Normal moveout transit time Transit_Time_Nominal Transit_Time Nominal transit time Transit_Time_Qfactor Transit_Time Transit time q-factor Transit_Time_SRD Transit_Time Transit time with respect to seismic reference datum Transit_Time_Sensor Transit_Time Transit time taken from tool sensor Transit_Time_Shear Transit_Time Shear wave transit time Transit_Time_Slope Transit_Time Transit time slope Transmission_Coefficient Ratio Ratio of the amplitude of a transmitted wave to that of the incident wave; may be greater than 1. Transverse_Amplitude Amplitude Amplitude of transverse component in multi-component seismic. Transverse_Dispersivity_Coefficient Coefficient The coefficient used as a multiplier of interstitial velocity to estimate dispersion normal to the direction of movement for a displacement front. Transverse_Isotropy_Coefficient Coefficient The degree of transverse isotropy in a medium; that is, having the different property values when measured within or normal to a plane. Usually represented by the 5 coefficients of the Stiffness matrix: C11, C13, C33, C44, C66. Transverse_Relaxation_Time Relaxation_Time Transverse, or spin-spin, relaxation time constant for transverse magnetization decay rate of nuclei; normally abbreviated by symbol T2. Treatment_Bottom_Depth Depth Depth of the borehole at the moment of the treatment Treatment_Displacement_Volume Volume Dead volume including the surface treating lines to be pumped to move the treating fluid down to formation. In cementing it is the volume (through casing/tubing/ drillpipe) up to the landing collar; in acidizing it is the tubing volume to perforations Treatment_Flow_Path Type Indicates how the fluid is pumped into the well e.g. by the casing, the tubing, the annulus Casing-tubing ... Treatment_Number Identifier Internal Dowell treatment number Treatment_Rate Flowrate Total flowrate pumped downhole in a well treatment activity Trimmed_Length Length Length of material which has been cut away either to prevent fatigue rupture on a cable or a coiled tubing or to connect an equipment Trona_Volume_Fraction Volume_Fraction The volume fraction of trona with respect to the total volume. Trough_Peak_Amplitude_Ratio Ratio Ratio of amplitudes of peak and trough. Trough_Peak_Delta_Amplitude Amplitude Amplitude difference between trough and peak. Trough_Peak_Delta_Depth Thickness Depth difference between trough and peak where trough occurs first in increasing depth Trough_Peak_Delta_Time Time_Interval Time difference between trough and peak Trough_Trough_Amplitude_Ratio Ratio Ratio of amplitudes of two troughs. Trough_Trough_Delta_Amplitude Amplitude Amplitude difference between two troughs. Trough_Trough_Delta_Depth Thickness Depth difference between successive troughs Trough_Trough_Delta_Time Time_Interval Time difference between two troughs True Modifier Conformable to an essential reality. In Earth science, determined with reference to the earth axis rather than the magnetic poles. True_Common_Depthpoint_Number Ordinal_Number CDP Line Number True_Common_Depthpoint_Offset Offset Shot position relative to the CDP Line True_Common_Midpoint_Position Rectangular_Position Common midpoint (CMP) position True_Common_Midpoint_X_Coord X_Coordinate X-coordinate of Common midpoint (CMP) position True_Common_Midpoint_Y_Coord Y_Coordinate Y-coordinate of Common midpoint (CMP) position True_Common_Midpoint_Z_Coord Z_Coordinate Z-coordinate of Common midpoint (CMP) position True_Receiver_Line_Position Receiver_Line_Position True position in a receiver line True_Receiver_Line_Position_Rho Receiver_Line_Rho Horizontal (x-y) distance from origin of true position in a receiver line. True_Receiver_Line_Position_Theta Receiver_Line_Theta Horizontal angle of true position in a receiver line, measured counter-clockwise from x-axis. True_Receiver_Line_Position_Z Receiver_Line_Z Z-coordinate of true position in a receiver line. True_Receiver_Position Rectangular_Position True receiver position True_Receiver_Position_X_Coord X_Coordinate X-coordinate of true receiver position. True_Receiver_Position_Y_Coord Y_Coordinate Y-coordinate of true receiver position. True_Receiver_Position_Z_Coord Z_Coordinate Z-coordinate of true receiver position. True_Scale_Latitude Latitude Latitude at which scale is true, as with a standard parallel. True_Source_Line_Position Source_Line_Position True position in a source line. True_Source_Line_Position_Rho Source_Line_Rho Horizontal (x-y) distance from origin of true position in a source line. True_Source_Line_Position_Theta Source_Line_Theta Horizontal angle of true position in a source line, measured counter-clockwise from x-axis. True_Source_Line_Position_Z Source_Line_Z Z-coordinate of true position in a source line. True_Source_Position Rectangular_Position True source position True_Source_Position_X_Coord X_Coordinate X-coordinate of true source position. True_Source_Position_Y_Coord Y_Coordinate Y-coordinate of true source position. True_Source_Position_Z_Coord Z_Coordinate Z-coordinate of true source position. True_Source_Sensor_Position Rectangular_Position Position of sensor placed near source, for detection of shot event. True_Source_Sensor_Position_X_Coord X_Coordinate X-coordinate of position of sensor placed near source, for detection of shot event. True_Source_Sensor_Position_Y_Coord Y_Coordinate Y-coordinate of position of sensor placed near source, for detection of shot event. True_Source_Sensor_Position_Z_Coord Z_Coordinate Z-coordinate of position of sensor placed near source, for detection of shot event. True_Stratigraphic_Thickness Thickness Cumulative thickness of an earth layer, measured perpendicular to the bedding plane, thus eliminating any offset effect due to borehole deviation or structural dip. Also called True Bed Thickness. True_Stratigraphic_Thickness_Depth Depth The depth of a point relative to a True Stratigraphic Thickness (TST) Index. Such indices may be local to a particular zone interval, hence their values can only be compared to other values referenced to the same index. True_Vertical_Depth Depth The true vertical depth from the surface of the Earth to a particular subsurface point. True_Vertical_Thickness Thickness Isochores obtained by correcting for structural dip in order to account for the lateral offset of the intersections of the well bore with the top and bottom of a layer. True_Vertical_Thickness_Depth Depth The depth of a point relative to a True Vertical Thickness (TVT) Index. Such indices may be local to a particular zone interval, hence their values can only be compared to other values referenced to the same index. Tube_Drift_Diameter Drift_Diameter Drift diameter of tube or body of equipment item. Tube_Material Material_Code Material composition of the tubular product. Tube_Nom_Inside_Diameter Nom_Inside_Diameter Nominal inside diameter of body or actual inside diameter tube (for API spec. drill pipe) Tube_Nom_Length Nom_Length Nominal length of tube of body of equipment item. Tube_Nom_Outside_Diameter Nom_Outside_Diameter Nominal outside diameter of body or API nominal outside diameter of tube Tube_Tensile_Yield Tensile_Yield Maximum Force which can be applied to a tube or body without causing permanent deformation. Tube_Torsional_Yield Torsional_Yield Maximum torque which can be applied to the tube or body without causing permanent deformation. Tube_Upset_Type Type Type of upset in tube or body Tube_Wall_Thickness Thickness Wall thickness of tube or body of equipment item. Tubing_Shoe_Depth Depth Tubing shoe depth Tubular_Code Code Specific code of the tubular goods. Tubular_String_Component_Rank Rank A rank denoting the order of the element in a string of tubular drilling equipment. Tubular_String_Connect_Type Type The string tubular equipment connection number that is at the top. Allowed values are: UNKNOWN, 1st connection, and 2nd connection. Tubular_String_Location_Type Type The location of the super tubular equipment where the sub tubular equipment is attached. Allowed values are: UNKNOWN, attached outside of super string equipment, and attached inside of super string equipment Tubular_String_Offset Length The distance from the mid-point of the sub tubular equipment to the bottom of the super tubular equipment where the sub tubular equipment is attached. Tubular_Type Type The type of a Tubular used in some activity or installed in and part of the well structure, e.g. Casing, Production Tubing, etc. Turbulence_Coefficient Indicator The coefficient that describes the additional pressure drop due to inertial effects for high velocity gas flow. Two_Way_Time Acoustic_Travel_Time The time required for an acoustic wave to travel from its source to a reflector and return to a receiver. Type Data_Valued_Property The type of any item. Applies to all items in all domains. UNKNOWN Property Unknown property type; used to assert that a specific Property Code cannot be determined from the information provided. URL Address Address of Worldwide Web site; acronym for Universal Resource Locator UWI Identifier The unique Identifier given to a well or a borehole specified in a given naming system. This identifier can be granted by either an official regulatory commission such as the API 12/14 digits, the Canadian Petroleum Association (CPA) or by any organization (user, customer), described in Well.Naming_System. Ultrasonic_Caliper Caliper Borehole diameter as measured by an ultrasonic logging device. Uncertainty Statistical_Property Precision with which a measurement is known; often implies a 50-50 chance that any one of a series of measurements will fall within a given range; the unit quantity is determined by that of data value. Uncertainty is not necessarily related to Accuracy. Uncertainty_Radius Uncertainty Magnitude of uncertainty for a measurement being represented as a position in 2D or 3D coordinate space, such as a geographical position. Unconformity_Type Type The type of an unconformity in the Earth subsurface, e.g. Joint, Disconformity, Diastem, etc. Undisturbed_Zone_Bound_Water_Volume_Fraction Water_Volume_Fraction The volume fraction of bound water in the undisturbed zone with respect to the total volume. Undisturbed_Zone_Dissolved_Salt_Volume_Fraction Volume_Fraction The volume fraction of dissolved salt in the undisturbed zone with respect to the total volume. Undisturbed_Zone_Free_Water_Volume_Fraction Water_Volume_Fraction The volume fraction of free water in the undisturbed zone with respect to the total volume. Undisturbed_Zone_Gas_Volume_Fraction Gas_Volume_Fraction The volume fraction of gas in the undisturbed zone with respect to the total volume. Undisturbed_Zone_Hydrocarbon_Volume_Fraction Hydrocarbon_Volume_Fraction The volume fraction of hydrocarbon in the undisturbed zone with respect to the total volume. Undisturbed_Zone_Irreducible_Water_Volume_Fraction Water_Volume_Fraction The volume fraction of irreducible water in the undisturbed zone with respect to the total volume. Undisturbed_Zone_Oil_Volume_Fraction Oil_Volume_Fraction The volume fraction of oil in the undisturbed zone with respect to the total volume. Undisturbed_Zone_Water_Volume_Fraction Water_Volume_Fraction The volume fraction of water in the undisturbed zone with respect to the total volume. Unit_Attribute Attribute_Name Name of Object Attribute where Unit may be found if not otherwise specified Unit_Canonical_Form Unit_Code Canonical form of defining unit for this Dimension Unit_Code Code Code of a Unit Symbol in the SDM/OSDD Units model or of an RP66 Unit expression. Unit_Column Column_Name Database column name where Unit may be found if not otherwise indicated. Unit_Cost Cost Cost per unit amount Unit_Dimension_Code Code Code of a Unit Dimension in the SDM/OSDD Units model Unit_Namespace_Code Namespace_Code Code of the Namespace for a Unit Symbol Unit_Object Object_Name Name of Object where Unit may be found if not specified Unit_Quantity_Code Code Code of a Unit Quantity in the SDM/OSDD Units model Unit_Quantity_Column Column_Name Name of column in database table where Unit may be found if not otherwise indicated. Unit_Quantity_Table Table_Name Name of database table where Unit may be found if not otherwise indicated. Unit_System_Code Code Code of a Unit System in the SDM/OSDD Units model. Unit_Table Table_Name Name of database table where Unit may be found if not otherwise indicated. Up_Load Load Upward load exerted on an equipment item. Up_Stroke Stroke_Length Up stroke distance, as used for drilling jars. Maximum stroke travel in shock/cushion sub Upper_Fluid_Type Fluid_Type The type of fluid found in the layer above a reference surface (e.g. Water in layer above a Fluid Contact in a Reservoir,) Upper_Surface_Relation Type The type of relationship between a surface and the ones above (e.g. the surfaces below a Horizon are onlapping.) Upset_Diameter Diameter Upset diameter (such as replaceable sleeve stabilizer) Upstream_Coil_Pressure Pressure Coil working pressure upstream of the choke box Uranium_Concentration Concentration Concentration of Uranium by weight Uranium_Dry_Weight_Fraction Dry_Weight_Fraction Ratio of dry weight of uranium to total dry weight Uranium_Potassium_Ratio Ratio Ratio of concentration of Uranium to that of Potassium. Uranium_Yield Elemental_Yield Elemental contribution of Uranium with respect to total. Use_Checkshot_Flag Flag A processing option indicating whether or not Checkshot survey data should be used for depth-time conversion. User_Data_Ident Data_Mask User-defined mask User_Evaluation_Code Data_Mask Auxiliary user-defined mask User_Trace_Selection Flag Good/bad marker Validation_Flag Flag Flag indicating that validation will be or has been performed on the data. Value_Domain_Code Code Code of an SDM Value Domain Value_Long Multi_Use_Property Value if of data type Long Value_Number Multi_Use_Property Value if of data type Number Value_String Multi_Use_Property Value if of data type String Value_Type Code Code of value type of data Value_Type_Code Code Code of value type of data Value_Type_Column Column_Name Name of column in database table where value type may be found if not otherwise indicated. Value_Type_Table Table_Name Name of database table where value type may be found if not otherwise indicated. Valve_Inside_Diameter Inside_Diameter Inside diameter of the valve assembly Variable_Deck_Load Load Current temporary load on the rig deck Variance Statistical_Property A measure of the width of the probability distribution for a single random variable; the square of standard deviation. Velocity Data_Valued_Property The rate of change of the displacement of a body in time. Velocity_Alpha_Factor Gradient Gradient factor a for Faust 6th root velocity function v(z) = a * z**(1/6) Velocity_At_Z0 Acoustic_Velocity (Instantaneous) Velocity at surface reference z=0 (z is time or depth). Velocity_Beta_Factor Gradient Gradient factor b for Faust 3rd root velocity function. v(z) = b * z**(1/3) Velocity_Ellipticity_Azimuth Azimuth Fastest direction of elliptic anisotropic velocity (i.e. ellipse major axis) measured clockwise from grid north in degrees. Velocity_Ellipticity_Flattening Ratio Degree of velocity elliptical anisotropy, in the range 0 (isotropic) to 1, defined as the ratio of the difference between the major and minor axes to the major axis of the velocity ellipse. Velocity_Gamma_Factor Gradient Gradient factor g for Faust Nth root velocity function v(z) = g * z**(1/n) Velocity_Gradient_In_Depth Gradient First derivative of velocity versus depth Velocity_Gradient_In_Time Gradient First derivative of velocity versus time. Velocity_K_Factor Gradient Velocity depth gradient, dv/dz used in some velocity functions like linear velocity : v(z) = v_0 + k*z depth of burial : v(z,z_1) = v_0 + k_1*z_1 + k_2*(z-z_1) Velocity_To_Seismic_Datum Acoustic_Velocity Velocity of the medium between the zero-time reference of a particular survey to the Seismic Reference Datum. Velocity_Uncertainty Uncertainty Uncertainty of a velocity measurement. Version Identifier Software version number Vert_Hor_Permeability_Ratio Vert_Hor_Ratio The ratio of vertical to horizontal permeability in a permeable medium. Vert_Hor_Ratio Ratio The ratio of some property measured vertically to that of the same property measured horizontally; several such property types are used to characterize formation anisotropy. Vertical_Datum_Code Code Code of the permanent Vertical Datum to which the local elevation reference is related. Typical Vertical Datums are "MSL" and "GL". Vertical_Datum_Name Name Name of the permanent Vertical Datum to which the local elevation reference is related. Typical Vertical Datums are "Mean Sea Level" and "Least Astronomic Tide". Vertical_Depth_Offset Depth_Offset Offset in true vertical depth versus some true vertical depth reference. Vertical_Formation_Resistivity Formation_Resistivity Formation resistivity measured perpendicular to layering. (for "Transverse-Isotropic (TI)" rock Vertical_Geometric_Skin Skin_Factor In a horizontal well, skin effect due to the limited entry in the vertical direction. Vertical_Lift_Depth Depth Tubing depth in vertical lift fluid flow computation Vertical_Lift_Flow_Regime_Flag Flag Flag identifying flow regime flag at some depth Vertical_Lift_Pressure Pressure Computed pressure at some depth in tubing Vertical_Lift_Temperature Temperature Computed temperature at some depth in tubing Vertical_Mean_Permeability Geometric_Mean_Permeability Geometric mean permeability in the vertical plane (Y-Z) of the reservoir Vertical_Mobility Mobility A measure of the ease with which a fluid can be moved vertically in a specific medium (i.e. rock). The ratio of the effective vertical permeability and the viscosity of the fluid. Vertical_Permeability Directional_Permeability A permeability oriented vertically perpendicular to the bedding plane of the stratum. Usually abbreviated as Ky. Vertical_Rotation Inclination Vertical inclination of the ellipses of uncertainties relative to the wellbore at the associated survey point. Vertical_Section Length Vertical Section, historical name given to the horizontal distance from the surface location to the downhole point (horizontal counterpart to True Vertical Depth). Vertical_Section_Azimuth Azimuth Angle between the true north and the vertical section plane. Vertical_Section_Origin Location The location and orientation of the vertical section plane in which vertical section distances are measured. Vertical_Size Height The size of any object as measured vertically Vertical_Time_Thickness Time_Interval Vertical time difference between layers. Viscosibility Data_Valued_Property Normalized derivative of viscosity: -(dv/dp)/v where v=viscosity and p=pressure. Viscosity Data_Valued_Property The property of a substance offering internal resistance to flow; a measure of the degree of fluidity. Visibility Length Maximum distance at which objects can still be discerned or identified visually. Visible_Width Width For core images, the width of the core which is visible in the image. Vitrinite_Reflectance Data_Valued_Property The optical reflectivity of solid organic constituents of rock, known as vitrinite, which provides an indication of thermal maturity. Volume Data_Valued_Property A measure of the space occupied by a body in cubic units; e.g., cm3, in3, quarts, liters, etc. Volume_Fraction Ratio The ratio of the volumes occupied by two components, or by one component to the total volume of the system. Volume_Per_Length Data_Valued_Property The measure of volume per linear displacement, usually given in bbl/in, bbl/ft, U.S. gal/ft. Volume_Reflection_Spectrum Amplitude Volume Reflection Spectrum, i.e. spectral decomposition of the amplitude response in interval Volume_Safety_Factor Safety_Factor Volume in excess of what has been calculated for the job. Used to account for loss or safety margin Volume_Type Type The type of an Earth subsurface region or volume, e.g. Formation, Reservoir, Tank, Bed, etc. Volumetric_Coefficient Data_Valued_Property Multiplicative factor (Volume per pulse), sometimes called K Factor. Volumetric_Photoelectric_Factor Data_Valued_Property A lithology indicator computed from bulk density and Photoelectric Factor; often expressed in an approximation unit barns/cc. Von_Mises_Stress Stress Normalized sum of the square of the differences of principal stresses applied to a material, e.g. for coiled tubing hoop, bending & radial. See Von_Mises_To_Yield_Ratio. Von_Mises_To_Yield_Ratio Ratio Ratio of the Von_Mises_Stress to the Yield Strength of the material : It helps determine whether the material has yielded (permanently damaged) by comparing to the yield_stress (>1, permanently deformed). Vsplib_Waveform_Header Data_Valued_Property The waveform header used in Vertical Seismic Profile. The structure of the data is specific to Schlumberger Borehole Seismic applications. Wall_Building_Coefficient Data_Valued_Property (Fracturing) Measure of the capability of a fluid flowing in front of a porous media to build up a filter cake inhibiting the fluid leakoff through the porous media. Non RPP66 unit :length/(time)**1/2 e.g. ft/min**1/2 Warmup_Duration Duration Duration between power-on time and acquisition start time. Washout_Caliper_Diff Caliper The degree of a borehole ovality beyond which caliper data becomes unreliable due to bad contact with the tool pads. Washout_Caliper_Ext Caliper The extension of a borehole diameter beyond which caliper data becomes unreliable due to bad contact with the tool pads. Water_Acoustic_Velocity Acoustic_Velocity Sound velocity in water. Typical value under reservoir conditions is 1550 m/s. Water_Activity Volume_Fraction Measure of the water concentration in aqueous solutions expressed as a decimal fraction between 0 and 1 ( = 1 for pure water) Water_Bubble_Flow_Velocity Flow_Velocity Water Bubble Velocity Water_Compressibility Compressibility The compressibility of water at a given pressure and temperature. Water_Concentration Volume_Fraction Water Concentration per fluid Volume Water_Conductivity Conductivity Conductivity of Connate Water (in formation) Water_Connection_Size Diameter Standard water pipe size connection supplied on the equipment inlet Water_Cut Volume_Fraction The percent of water per total volume of liquid over a period of time for a product flow network unit. Water_Density Density The density of water. Water_Depth Depth Water depth Water_Flow_Velocity Flow_Velocity Flow velocity of water component of fluid. Water_Flowrate Flowrate Rate of flow of water Water_Formation_Volume_Factor Formation_Volume_Factor Ratio of water volume at specified (typically, reservoir) conditions to the water volume at surface (stock tank) conditions. Normally abbreviated Bw; typical range .99 - 1.07. Water_Fraction Volume_Fraction Volumetric fraction of water in the total fluid Water_Gravity Specific_Gravity The ratio of the density of the produced or reservoir water to that of pure water at atmospheric conditions Water_Holdup Holdup Volume fraction of water in the upward-moving stream of a producing well. Water_Mass_Flowrate Mass_Flowrate Mass flowrate of water. Water_Metering_Line_Size Diameter Diameter of the water metering line Water_Neutron_Capture_Cross_Section Neutron_Capture_Cross_Section The macroscopic capture cross section, i.e. the effective cross sectional area per unit volume, of water for the capture of neutrons. Water_Oil_Ratio Ratio A measure of the volume of water which is produced with a given quantity of oil. Water_Rate_Meter_Type Type Type of liquid meter used to measure the water rate Water_Resistivity Resistivity Resistivity of connate (formation) water Water_Salinity Salinity Total salts in solution (Na, K, Cl, So4, ..). Normal sea water has around 35,000 ppm (parts per million) salinity. Less than 2,000 ppm is considered "fresh". Water_Saturation Saturation The extent to which the pore space in a formation contains water. Water_Saturation_At_Breakthrough Water_Saturation Water saturation at the breakthough point. In Special Core Analysis, breakthough is the appearance of the injected fluid at the outlet face of the rock sample. Water_Saturation_At_Breakthrough_FF Water_Saturation Water saturation at the breakthough point, calculated from fractional flow curve (SCAL SwBkFF). In Special Core Analysis, breakthough is the appearance of the injected fluid at the outlet face of the rock sample. Water_Saturation_Min_So_3Phase Water_Saturation The water saturation at minimum oil saturation in a three phase system. (SCAL SWM) Water_Viscosibility Viscosibility Normalized derivative of viscosity for water: -(dv/dp)/v where v=viscosity and p=pressure. Water_Viscosity Viscosity The viscosity of water at specific temperature and pressure conditions. Water_Viscosity_Correlation Name Model used to compute water viscosity Water_Volume_Fraction Volume_Fraction The volume fraction of Water with respect to the total volume; the product of Porosity and Water_Saturation Water_Wettability_Index Wettability_Index Relative affinity of a mineral surface for water. Wave_Azimuth Azimuth Azimuth of the direction from which the waves are coming. Wave_Differential_Energy Gradient The change in attenuation of an acoustic wave (compressional, shear or Stoneley) per unit length. Wave_Height Height Average trough-to-peak height of the waves. Wave_Period Time_Interval Average elapsed time between the passing of two wave peaks. Waveform_Number Ordinal_Number Waveform number Wavelet_Type Type Type of wavelet used to deconvolve seismic data or to convolve with a basic reflection model to produce synthetic seismic data. Wavenumber Data_Valued_Property Spatial frequency, reciprocal of wavelength Weathering_Depth Depth Depth of the weathered layer, the near-surface low velocity layer consisting of unconsolidated material and rock in which air rather than water fills the pore space. Weathering_Depth_CDP Weathering_Depth Depth of weathered layer at a CDP. Weathering_Velocity Acoustic_Velocity Average acoustic velocity of the weathered layer, the near-surface low velocity layer consisting of unconsolidated material and rock in which air rather than water fills the pore space. Weathering_Velocity_CDP Weathering_Velocity Weathering velocity at a CDP. Weight Force The force with which a body is attracted toward the center of the earth or any celestial body by gravitation. The product of the mass of the body by the local gravitational acceleration. Weight_Indicator_Load Load Weight indication as measured at the sensor. In a coiled tubing unit, the sensor is located at the base of the injector head. Weight_On_Bit Force The downward force exerted by the drillbit on the formation being drilled. Weight_Per_Joint Weight Weight of each joint in a string of equipment Weight_Safety_Factor Safety_Factor Weight in excess of what has been calculated for the job. Used to account for loss or safety margin Welded_Section_Flag Flag Y/N : does the section has a weld or not : used as a weak point flag in coiled tubing. Well_Count Count The count of the numbers of wells. Well_Job_Count Count Total Number of jobs Well_Name Name Name given to a well, quite possibly the legal name. The name may vary as ownership and rights are transferred. Well_Production_Control_Mode Type Describes what controls the production flow of the well (e.g. constant wellhead pressure, constant flowrate) Well_Projection_Type Type Characterizes the way a well borehole is projected onto a cross section. Well_Spacing Reservoir_Distance Average distance between two wells, connected or not to regulatory petroleum laws Well_Status Status A property indicating the operational condition of a well: proposed, active, abandoned, etc. Well_Test_Model Type Type of well test: e.g. Conventional, Horizontal, Interference, etc. Well_Test_Model_Type Type Type of Well Test Model selected Well_Test_Type Type The type of test conducted on a Well. Well_Thermal_Gradient Thermal_Gradient The rate of change of temperature with measured depth in a well; equivalent to Geothermal_Gradient for a vertical well whose temperature has stabilized. Well_To_Boundary_Distance Reservoir_Distance The distance between the well trajectory and the adjacent reservoir boundary distance. Well_To_Boundary_Distance_X X_Coordinate The distance between the well trajectory and the adjacent reservoir boundary in the X direction. Well_To_Boundary_Distance_Y Y_Coordinate The distance between the well trajectory and the adjacent reservoir boundary in the Y direction. Well_To_Fault_Angle Plane_Angle The angle between the well and either sealing fault in a wedge well test model. Well_To_Fault_Distance Reservoir_Distance The distance between the sealing fault and the well trajectory. Well_To_Fracture_Element_Distance Reservoir_Distance Distance from Borehole to start of fracture element Well_Treatment_Fluid_Type Fluid_Type Type of Fluid used in Well Treatment operation Well_Treatment_Type Type Matrix acidizing, Cementing, Acid fracturing, Hydraulic fracturing, Gravel Packing ... Wellbore_Purpose Type A property indicating the purpose of a wellbore (borehole). Wellbore_Shape Shape Type of wellbore trajectory shape; common types are: build & hold, S shaped, vertical, horizontal. In the early stages of well planning, this information, along with some key parameters, are used to generate an approximate well profile - without the requirement for detailed trajectory planning. This information is also of value for wells that have already been drilled because it is difficult to categorize wells by their detailed trajectory. Wellbore_Status Status A property indicating the operational condition of a wellbore: proposed, active, abandoned, etc. Wellbore_Storage Data_Valued_Property Measure of the ability of the wellbore to store fluid ("afterflow" when a well is shut in) or unload fluid (when a well is opened to flow). Wellbore_Storage_Type Type Describes Wellbore storage behavior as either constant, variable (exp), or variable (erf). Wellbore_Tortuosity_Amplitude_Angle Plane_Angle Amplitude translated as an inclination of the sinusoidal function fitting the survey station points and simulating a real well path Wellbore_Tortuosity_Wave_Length Length The wave length of the sinusoidal function fitting the deviation survey station points and simulating a real well path Wellhead_Connection_Type Type Type of wellhead connection (flange, tree- saver ..); data must identity the mechanical item unambiguously to allow a hydraulic connection e.g. Studded Flange API BX150-15000 psi. Wellhead_Flowing_Pressure Pressure Pressure at the Wellhead with well flowing Wellhead_Flowing_Temperature Temperature Temperature at the Wellhead with well flowing Wellhead_Gas_Flowrate Gas_Flowrate Gas flowrate at the Wellhead Wellhead_Liquid_Flowrate Liquid_Flowrate Liquid flowrate at the Wellhead Wellhead_Pressure Pressure The producing or shutin pressure at the top of the well before any surface pressure drops. Wellhead_Producing_Gas_Liquid_Ratio Gas_Liquid_Ratio Ratio of volume of gas to volume of liquids produced at the wellhead. Wellhead_Producing_Liquid_Gas_Ratio Liquid_Gas_Ratio Ratio of volume of liquids to volume of gas produced at the wellhead; used primarily to express the amount of condensate produced in gas wells; typical unit is barrel per million cubic feet (RP66: 1E-6 bbl/ft3) Wellhead_Producing_Water_Cut Producing_Water_Cut Water Cut at the Wellhead while well is producing Wellhead_Shutin_Pressure Pressure Static wellhead pressure during test Wellhead_Temperature Temperature The temperature at the wellhead occurring at the time of the activity being performed on the well. Wet_Gas_Critical_Pressure Critical_Pressure The pressure needed to condense a wet gas at its critical temperature (Wet gas : mixture of free gas plus condensate) Wet_Gas_Critical_Temperature Critical_Temperature The highest temperature at which the gas can exist as a liquid and above which its vapor cannot be liquefied regardless of the amount of pressure (Wet gas - mixture of free gas plus condensate) Wet_Gas_Gravity Gas_Gravity The ratio of the molecular weight of the wet gas to that of air (Wet gas - mixture of free gas plus condensate) Wettability_Index Data_Valued_Property Relative affinity of a mineral surface for hydrophilic (water wet) or hydrophobic fluids. Wetting_Contact_Angle Plane_Angle Angle between a fluid droplet and a solid surface at the point of contact; the lower the angle (measured inside the droplet), the greater the adhesion and thus the greater the wettability of the solid to that fluid. Wetting_Type Type Classification of the wetting characteristic of the rock, such as Oil Wet or Water Wet. Wheel_Circumference Length Wheel Circumference Width Length The measurement taken at right angles to the length. Wind_Azimuth Azimuth Azimuth of the direction from which the wind is blowing. Wind_Velocity Velocity Velocity of the wind Windchill_Temperature Temperature A measure of the combined chilling effect of wind and low temperature on living things, also named chill factor, e.g., according to US weather service table, an air temperature of 30 degF with a 10 mi/h corresponds to a "wind-chill" of 22 degF. Window_End_Time End_Time End time of the processing window. Window_Start_Time Start_Time Start time of the processing window. Wire_Diameter Outside_Diameter Diameter of wire, such as that used in a mesh or a slotted liner Wireline_Tool_Type Tool_Type The type of a Tool usually used in some wireline activity, e.g. CNTA, USIT, AIT, etc. Working_Pressure Pressure Pressure at which an equipment item normally operates Working_Temperature Temperature Temperature at which an equipment item normally operates X_Acceleration Acceleration Acceleration along the X-axis. X_Coordinate Coordinate X-coordinate of Location X_Direction_Permeability Directional_Permeability Permeability in X Direction X_Displacement Displacement Displacement in the X Direction relative to some coordinate system; e.g., the X-Component of the Well departure from the vertical. X_Display_Identifier System_Identifier XServer Id on which application is to display output X_Magnetometer Magnetic_Field_Strength Magnetic Field Strength along the X-axis. X_Transverse_Amplitude Amplitude X component of Transverse_Amplitude in multi-component seismic. Y_Acceleration Acceleration Acceleration along the Y-axis. Y_Coordinate Coordinate Y-coordinate of Location Y_Direction_Permeability Directional_Permeability Permeability in Y Direction Y_Displacement Displacement Displacement in the Y Direction relative to some coordinate system; e.g., the Y-Component of the Well departure from the vertical. Y_Magnetometer Magnetic_Field_Strength Magnetic Field Strength along the Y-axis. Y_Transverse_Amplitude Amplitude Y component of Transverse_Amplitude in multi-component seismic. Yield_Strength Pressure Unit stress which will produce a small amount of deformation generally equal to a strain of 0.2%. This value is a little greater than the Elastic limit. It is often supplied by the manufacturer of the material. Yield_Stress Shear_Stress Resistance to initial flow; the stress required to start fluid movement. Specifically, shear stress at 0 shear rate for Bingham Plastic (BP) rheological model, otherwise named Bingham yield value or yield point. BP fluid remains static until applied forces build up to the point where it starts to move. See Plastic_Viscosity. Young_Modulus Elastic_Modulus The stress-strain ratio when a body is pulled or compressed. Z_Acceleration Acceleration Acceleration along the Z-axis. Z_Coordinate Coordinate Z-coordinate of Location Z_Factor Coefficient The factor which corrects for the deviation of a gas from the ideal gas law when calculating PVT relationships. Z_Gravity Gravity Strength of the z-axis component of the gravitational field at some location; used to correct total z-axis acceleration of a logging tool to compute actual tool movement. Z_Magnetometer Magnetic_Field_Strength Magnetic Field Strength along the Z-axis. Z_Transverse_Amplitude Amplitude Z component of Transverse_Amplitude in multi-component seismic. Zenith_Angle Plane_Angle Angle from an upward-pointing vertical line, measured in a vertical plane. A horizontal line has a zenith angle of 90 degrees Zero_Crossing_Count Count Count of zero crossings of waveform(s). Zinc_Yield Elemental_Yield Elemental contribution of Zinc with respect to total. Zirconium_Yield Elemental_Yield Elemental contribution of Zirconium with respect to total. Zone_Length Interval_Length The length of a zone, usually along the borehole. Zone_Name Name Zone Name Zone_Number Ordinal_Number An ordinal identifier that uniquely characterizes each zone Zone_Set_Type Type The type of a set of zone intervals traversing one or more Boreholes and/or one or more Earth subsurface Volumes. Zone_Start Depth The start depth of a zone, usually along the borehole. This may be the deeper or the shallower end of the zone. Zone_Stop Depth The stop depth of a zone, usually along the borehole. This may be the deeper or the shallower end of the zone. i_C4H10_Concentration Chemical_Concentration Concentration of iso-Butane (i-C4H10); typical volume concentration in natural gas is 0.3%. i_C5H12_Concentration Chemical_Concentration Concentration of iso-Pentane (i-C5H12); typical volume concentration in natural gas is 0.3%. i_C6H14_Concentration Chemical_Concentration Concentration of iso-Hexane (i-C6H14). n_C4H10_Concentration Chemical_Concentration Concentration of Normal Butane (n-C4H10); typical volume concentration in natural gas is 0.6%. n_C5H12_Concentration Chemical_Concentration Concentration of Normal Pentane (n-C5H12); typical volume concentration in natural gas is 0.25%. n_C6H14_Concentration Chemical_Concentration Concentration of Normal Hexane (n-C6H14). pH Concentration An indicator of the degree of acidity or basicity of an aqueous solution. A value of 7 denotes a neutral fluid, lower values correspond to acidic fluids and higher values to basic fluids.