Oil and Gas Terms Beginning with “N” — Page 3

A percentage share of production, or the value derived from production, which is free of the costs of drilling and producing, created by the lessor or royalty owner and borne by the lessor or royalty owner out of the… Read more →

Ownership in a share of production, paid to an owner who does not share in the right to explore or develop a lease, or receive bonus or rental payments. It is free of the cost of production, and is deducted from the… Read more →

Referring to a type of conventional electrical log in which the current emitting electrode (A) and the measure electrode (M) are placed close together on the sonde, and the current return electrode (B) and the measure… Read more →

A type of fault in which the hanging wall moves down relative to the footwall, and the fault surface dips steeply, commonly from 50o to 90o. Groups of normal faults can produce horst and graben topography, or a series… Read more →

The case in which a wavefront is parallel to an interface and its raypath is perpendicular, or normal, to the interface as the wave impinges upon the interface. Read more →

A type of acoustic energy that propagates in one direction while being confined in the other two directions, in this case by the borehole wall. Normal modes are propagated as reflections off the borehole wall, and exist… Read more →

The procedure in seismic processing that compensates for the effects of the separation between seismic sources and receivers in the case of a horizontal reflector. Read more →

The pore pressure of rocks that is considered normal in areas in which the change in pressure per unit of depth is equivalent to hydrostatic pressure. The normal hydrostatic pressure gradient for freshwater is 0.433… Read more →

A function of time and offset that can be used in seismic processing to compensate for the effects of normal moveout, or the delay in reflectionarrival times when geophones and shotpoints are offset from each other. Read more →

A unit of concentration for solutions of reagent chemicals used in testing mud chemistry. Normality provides a simple relationship between the volume in cm3 of reagent added during a titration and the chemical… Read more →

A device for measuring the density of fluids in a completed well, using a radioactive source of gamma rays and a detector. In most instruments, a 137Cs (cesium) or 241Am (americium) source is used to induce Compton… Read more →

Pertaining to a measurement of the nuclear magnetic properties of formation hydrogen. The basic core and log measurement is the T2 decay, presented as a distribution of T2 amplitudes versus time at each sample depth,… Read more →

What Is NMR Measurement in Petroleum Well Logging? Nuclear magnetic resonance (NMR) measurement in petroleum logging uses the magnetic properties of hydrogen atoms in pore fluids to characterise formation porosity, pore… Read more →

Mathematical methods that require iterative processing of data rather than applying deterministic equations. Some relationships can be solved only by numerical methods, including most integration problems, some… Read more →

A rendering of a model of a reservoir or field in entirely numerical formats. Numerical models, once built, may be used to perform many mathematical operations, including calculations of available reserves and… Read more →

The mathematical simulation of a numerical model of a reservoir's petrophysical characteristics to analyze and predict fluid behavior in the reservoir over time. Read more →