N

Nameplate Rating
The manufacturers' ratings as to speed, working pressure, horsepower, type of fuel, voltage requirements, etc. printed or stamped on the nameplate attached to equipment.

Naphthene Base Crude Oil
SEE: Asphalt Base Crude Oil.

National Topographic Series Survey Canada
A Canadian rectilinear grid system delineated by lines of latitude and longitude.

Native Gas
SEE: Formation Gas.

Natural Clay
A clay that is encountered when drilling various formations. The yield of these clays varies greatly, and they may or may not be purposely incorporated into the drilling fluid system.

Natural Flow
Production of oil to the surface by use of available reservoir energy which may be water pressure, free gas pressure, solution gas or a combination of these factors and without the use of artificial lift methods.

Natural Gamma Ray Spectroscopy Log
A well log in which the specific energy levels of natural gamma ray radiation are analyzed to provide a means to identify and quantify the elements (isotope) which are the sources of the radiation. This measurement is used primarily to determine clay content. Also referred to as: spectral gamma ray log.

Natural Gas
Gaseous forms of petroleum consisting of mixtures of hydrocarbon gases and vapors, the more important of which are: methane, ethane, propane, butane, pentane, and hexane. It may exist either in the gaseous phase or in solution with crude oil in reservoirs.

Natural Gas Futures Contract
A commodity contract traded on NYMEX to buy or sell natural gas for future month deliveries. One contract equals 10,000 MMBTUs of natural gas, with a standard delivery point of Henry Hub.

Natural Gas Liquid
Commonly abbreviated as : NGL. Hydrocarbon found in natural gas which has been liquefied at the surface in field facilities or in gas processing plants. NGL's include but are not limited to: ethane, propane, normal butane, isobutane, pentanes, debutanized natural gasoline, and plant condensate not recovered by mechanical separation. Liquid hydrocarbons extracted in gas processing plants are often referred to as plant products.

Natural Gas Liquid Products
The separate products derived from natural gas liquids, including butane (isobutane and normal butane), propane, propane mixtures and natural gasoline, but not ethane. Refer to DOE/ERA Regulations, Section 212.162.

Natural Gas Plant
SEE: Gas Processing Plant.

Natural Gas Policy Act Of 1978
Enacted on November 9, 1978 and became effective December 1, 1978. The Act has been amended, and it replaced or amended the Natural Gas Act. Refer to 15USC 3301-3432.

Natural Gas Stripping
The countercurrent bubbling of a gas through a fluid to remove certain components or impurities in the fluid.

Natural Ice Island
SEE: Ice Island.

Naturally Deviated Wellbore
A wellbore path which has deviated from vertical without use of deflection tools. Drilling tends to creep updip, for example.

Near Size Material
That material very nearly the size of the screen aperture, generally considered as plus or minus 25% of the aperture.

Needle Valve
A valve having a tapered gate that rests in a tapered orifice for extremely fine regulation of flow.

Negative Buoyancy
When a body weighs more than the weight of fluid that it displaces.

Negatively Skewed Bit
A bit with offset built into the cones in an opposite direction to that normally used.

Nema Enclosure
An electrical enclosure manufactured to National Electrical Manufactures Association (NEMA) standards.

Net Acre Feet
The total acre feet applicable to one owner based on a calculation of the owner's interest applied to the total acre feet in the entity involved.

Net Additional Burden
The decimal expression of the net additional nonoperating type burden which is payable out of the company's working interest. Does not include royalty reserved by the lessor(s).

Net Amount
The gross value plus or minus adjustments.

Net Back
Economic Regulatory Administration (ERA) defines, with respect to natural gas liquids, any transfer for value to a class of purchaser for which a percentage of the revenues from the first sale of natural gas liquids or natural gas liquid products is received.

Net Delivered/sold Volume
The volume of production delivered to a plant or sold. Net of exempt and nonexempt adjustments

Net Effective Gas Thickness
The cumulative net vertical gas thickness of gaseous hydrocarbons within a borehole.

Net Effective Oil Thickness
The cumulative net vertical thickness of liquid hydrocarbons within a borehole.

Net Heating Value
The gross heating value less the heat of condensation of any water formed in combustion.

Net Oil Computer
A combination of electronic and mechanical devices that automatically determines the amount of oil in a water and oil emulsion.

Net Pay
The cumulative reservoir rock thickness capable of producing commercial hydrocarbons, excluding nonproducing portions, within a specified interval.

Net Positive Suction Head
The differential, in feet of liquid pumped, of the pressure at the intake of a pump over the bubble point pressure of the liquid at pumping temperature. Commonly abbreviated as: NPSH.

Net Price Per Unit Amount
The gross price received less allowable deductions.

Net Production
Production derived from ownership of all working interests less any royalty, overriding or any other economic interests.

Net Profits Interest
An interest in a property which entitles the owner to receive a stated percentage of the net profit as defined in the instrument creating the interest. It is carved out of the working interest.

Net Profits Lease
When the lessor shares in the net proceeds of production after the lessee has recovered his initial investment. The various expenses to be allowed as deductions from gross proceeds are points of negotiation. Also applies to working interest relationships.

Net Reserves
Reserves derived from ownership of working interests less any royalty, override or other economic interests.

Net Reservoir Thickness
SEE: Net Pay.

Net Revenue Interest
The total interest a working interest owner has in a lease including any royalty interest. This excludes any royalty, overriding royalty, production payments, etc., that the owner owns that he must pay to others.

Net Taxable Amount
The value on which tax is based.

Net Volume
The gross volumes plus or minus applicable volume adjustments.

Net Working Interest
A working interest owner's gross working interest in production, less the related royalty, overriding royalty, production payment, and net profits interests.

Network Well
A well in which component wellbores may start at many points on the surface of the earth but are interconnected below the surface of the Earth, and are created for the acquisition of many primary geological targets. A network well may have many surface access points to shared geological targets.

Neutral Point
This term has been defined variously as: (1) The point where tension is zero.(2) The point where stresses are zero.

Neutralization
A reaction in which the hydrogen ion of an acid and the hydroxyl ion of a base unite to form water, the other ionic product being a salt.

Neutralization Number
The acidic content of a lubricating oil, normally expressed as milligrams of potassium hydroxide per gram of oil.

Neutralizing Amine
An amine introduced into a condensate or boiler system to neutralize acidity.

Neutron Log
A porosity log of a nuclear logging tool whose response is primarily related to hydrogen concentration in the formation. Used with other porosity information, the neutron log is useful to ascertain the presence of gas and determine mineralogy and shaliness.

New Contract
Under the Natural Gas Policy Act (NGPA), 1978, as amended, any contract entered into on or after November 9, 1978 for the first sale of natural gas not previously subject to an existing contract.

New Mexico Battery Code
A code assigned by the New Mexico Oil and Gas Conservation Commission to uniquely identify commingled oil/condensate tank batteries, for reporting purposes.

New Mexico Hole Code
A code assigned by the New Mexico Oil & Gas Conservation Commission to indicate that a lease has two or more wells per 40 acre spacing.

New Mexico Lease Control Identifier
An identifier assigned at the lease regulatory horizon level by the New Mexico Oil and Gas Conservation Commission to provide separate identification of each well horizon/zone with its parent lease regulatory horizon within each of the three sections of the Form C-115, Operator's Monthly Report; e.g., oil section; gas section; commingled section.

New Ocs Lease
Under the Natural Gas Policy Act (NGPA), 1978, as amended, with respect to the Outer Continental Shelf, a lease of submerged acreage entered into on or after April 20, 1977.

New Taxes Reimbursed Percentage
The percent of new tax increases on gas for which the buyer is obligated to reimburse seller.

New Well
Under the Natural Gas Policy Act (NGPA), 1978, as amended, a well for which surface drilling began on or after February 19, 1977, or the depth of which was increased by means of drilling on or after February 19, 1977.

Ngl
SEE: Natural Gas Liquid.

Ngpa
SEE: Natural Gas Policy Act of 1978.

Ngpa Category Type
An indicator of the Natural Gas Policy Act (NGPA) gas category for which gas from the well qualifies.

Nipple
A pipe fitting that is usually threaded on both ends and is less than 12 inches in length.

Nipple Up
To assemble a system of pipe, valves, and nipples as in a Christmas tree.

Nitroglycerine
A heavy, oily explosive poisonous liquid C3H5(NO3)3.

No Drift
A length of pipe which will not pass an API drift with reasonable pressure.

Node
(1) A point in a standing wave where a given characteristic of the wave field has zero amplitude.(2) A location on a marine cable that contains a positioning sensor, or a seismic source, or a receiver.

Noise
Any undesired signal that tends to interfere with the normal reception or processing of the desired signal. Origin may be electrical, traffic, small reflectors, etc.

Noise Logging
A well logging process for measuring the amplitude of background noise in the borehole environment, for specific frequencies in the audible range, at selected stations in the wellbore. It is used to ascertain fluid movement profiles and fluid movements behind tubing or casing.

Nominal Far Offset
The distance from center of source to farthest live receiver, as specified in the acquisition plan, and which is planned for a typical source occurrence.

Nominal Fold
SEE: Fold.

Nominal Near Offset
The distance from center of source to nearest live receiver, as specified in the acquisition plan, and which is planned for a typical source occurrence.

Nominal Spread Type
The spread used for the acquisition line which occurs for a typical source occurrence; e.g., split,end on, H.

Nominate
The method whereby the purchaser or seller establishes a volume of gas delivery to accomodate market conditions.

Nominated Quantity
The physical quantity of gas requested for a specific contract or for all contracts at a specific point.

Nomination
(1) A request for a physical quantity of gas under a specific purchase, sales, or transportation agreement or for all contracts at a specific point. A nomination will continue for a specified number of days or until superseded by another service request for the same contract.(2) The amount of oil or gas proposed to be taken from a field as reported to a regulatory agency, operator, transporter, etc.

Nomination Allocation
SEE: Capacity Allocation.

Nonassociated Gas
Gas produced from reservoirs that do not contain significant quantities of oil.

Nonconformance
Any deviation from specified requirements.

Nonconsenting Owner
A working interest owner who has elected not to participate in a project or operation.

Noncorrosive Hydrocarbon Service
Process streams under conditions which do not cause significant metal weight loss, selective attack, or stress corrosion cracking.

Nondestructive Evaluation
SEE: Nondestructive Testing.

Nondestructive Testing
Inspection to detect internal, surface and concealed defects or flaws in materials using techniques that do not damage or destroy the items being tested.

Nonfull Crested Thread
A thread on which the profiled or machined pipe surface still appears on the thread crests.

Nonincendive Circuit
A circuit that, under normal conditions, does not release sufficient energy to ignite a specific ignitible mixture.

Nonincendive Equipment
Electrical equipment which in its normal operating condition would not ignite a specific hazardous atmosphere in its most easily ignitible concentration.

Noninterest Property
Producing leases, units, and tracts of units in which the company owns no interest and is not the operator, but has need for identification for one of the following recording and/or reporting purposes: (1) The company purchases the crude oil and/or condensate production from such properties.(2) The company operates a plant or facility that processes the gas production from such properties and makes settlement for the gas and/or extracted product(s).(3) The company farms out acreage or contributes m

Nonoperator
A working interest owner other than the one designated as operator of the property.

Nonoperator Administrative Contact Fax Number
The facsimile number supplied by the nonoperator for financial information.

Nonoperator Administrative Contact Fax User Id
The Fax User ID supplied by the nonoperator for financial information.

Nonoperator Administrative Contact Name
The name of the individual supplied by the nonoperator to be contacted for financial information.

Nonoperator Administrative Contact Telephone Number The Telephone Number Supplied By The Nonoperator For Financial Information.

Nonoperator Administrative Contact X.400 E-mail Address The X.400 E-mail Address Supplied By The Nonoperator For Financial Information.

Nonoperator Individual Approving Afe
The name of the individual of the nonoperating company with the authority to approve the AFE.

Nonoperator Name
The name of the working interest owner other than the one designated as the operator of the property.

Nonoperator Technical Contact Fax Number
The Fax number supplied by the nonoperator for technical, engineering, or geological information.

Nonoperator Technical Contact Fax User Id
The Fax User ID supplied by the nonoperator for technical, engineering, or geological information.

Nonoperator Technical Contact Name
The name of the individual supplied by the nonoperator to be contacted for technical, engineering, or geological information.

Nonoperator Technical Contact Telephone Number
The telephone number supplied by the nonoperator for technical, engineering, or geological information.

Nonoperator Technical Contact X.400 E-mail Address The X.400 E-mail Address Supplied By The Nonoperator For Technical, Engineering, Or Geological Information.

Nonpressure Containing Weld
A weld, the absence of which will not reduce the pressure containing integrity of the part.

Nonrecoverable Usage
Production from a well which is burned in support facilities such as generators, boilers, etc.

Nonsensitive Reservoir
A reservoir in which ultimate recovery is not decreased by high reservoir production rates.

Normal Bhp
A reservoir is said to have a normal bottomhole pressure (BHP) when the initial BHP approximates the hydrostatic pressure of a column of salt water corresponding to the depth of the reservoir.

Normal Fault
A fault in which the hanging wall appears to have moved downward relative to the footwall.

Normal Solution
A solution containing one gram equivalent of the dissolved substance per liter of total solution.

Normally Closed Valve
A valve which will shift to the closed position upon loss of the power medium.

Normally Open Valve
A valve which will shift to the open position upon loss of the power medium.

North American Datum Code
The name of a latitude/longitude datum used as a standard reference point; e.g., North American Datum (NAD) 27; NAD 83.

North American Veritical Datum Code
An indicator of the name of a elevation datum used as a standard reference point; e.g., North American Vertical Datum (NAVD 29, NAVD88).

North Axis Direction
The basis for defining the North direction. Examples include: true, magnetic, local grid, and geodetic.

North Dakota Well Code
Used to categorize individual wells or properties (whichever constitutes the taxable entity) by relative oil well production rates as defined by North Dakota for determining and reporting North Dakota's gross production and extraction tax(es). Codes are assigned by the state of North Dakota. Codes are: h=high producer well (average daily production greater than 100 bbls for the month reported); m=moderate producer well (not stripper, not high producer); s=stripper well (certified as stripper by producer

North South Descriptor
The North/South descriptor that indicates the direction of a measurement from an identifiable line; e.g., lease; boundary; block.

North South Footage
The North/South footage or distance that represents the length of a measurement from an identifiable line; e.g., lease; boundary, block.

Northing
The map projection grid coordinate of a point measured northwards (positive) from the east-west line through the origin.

Nose
A short, plunging anticline without closure.

Notch
SEE: Notch Filter.

Notch Filter
Designated filter used to remove a narrow band of frequencies.

Nozzle
A projecting part with an opening; i.e., a piping connection on a vessel or pump, through which a fluid is discharged.

Npsh
SEE: Net Positive Suction Head.

Nuclear Cement Log
A well log of scattered gamma rays, differing from the density log in that the gamma-ray source and detector are so spaced as to be sensitive to the density of material in the annulus between casing and borehole wall.

Nuclear Log
A well log of some parameter in the borehole environment derived from techniques utilizing nuclear reactions taking place in the downhole logging tool and/or in the rocks surrounding the borehole. Nuclear logs usually are well logs obtained by using radiation sources in the logging tool.

Nuclear Magnetism Log
A well log designed to measure free fluid index. The free fluid index indicates the free fluid (the hydrogen in free fluid hydrocarbons and water) in the rocks surrounding the borehole. Also referred to as: Free Fluid Log or Nuclear Magnetic Resonance Log.

Number Of Stages
The total number of steps in a given process whereby one or more batches are pumped at different depth intervals within a wellbore.

Nutating Disc
Wobble disc used in a liquid flowmeter to transfer motion of the flowing fluid to the counter.

Nymex
New York Mercantile Exchange, a price reference point for natural gas futures contracts, with physical receipt and delivery at Henry Hub.

Nymex Pricing
A market pricing mechanism that provides an alternative to index pricing.