Oil and Gas Terms Beginning with “A” — Page 2

What Is Absolute Open Flow Potential? Absolute open flow potential (AOFP) quantifies the theoretical maximum rate a gas or oil well could deliver if bottomhole flowing pressure were reduced to zero (atmospheric),… Read more →

What Is Absolute Permeability? Absolute permeability quantifies the intrinsic ability of a porous rock to transmit a single fluid phase under a pressure gradient, independent of fluid properties. Measured when a rock is… Read more →

Absolute pressure is the measurement of pressure relative to a perfect vacuum, defined as the total force per unit area exerted by a fluid on its surroundings when referenced to zero pressure rather than to local… Read more →

Absolute volume is the volume that a unit mass of a solid or liquid material occupies or displaces in a fluid system. In petroleum drilling engineering, it is defined as the volume per unit mass of a substance,… Read more →

Absorbing boundary conditions (ABCs) are numerical algorithms applied along the outer edges of a finite computational domain in seismic wave simulation to suppress artificial reflections that would otherwise propagate… Read more →

Absorptance is the ratio of the radiant or luminous flux absorbed by a body to the total flux incident upon it. Expressed as a dimensionless number between 0 and 1, absorptance describes what fraction of incoming… Read more →

Absorption in petroleum engineering refers to the process by which a gas or vapor is taken up and dissolved into the bulk phase of a liquid, as distinct from being captured only on the surface of a solid. In oil and gas… Read more →

An absorption band is a range of wavelengths (or equivalently, frequencies or wavenumbers) of electromagnetic radiation at which a given substance absorbs energy preferentially, reducing the intensity of transmitted or… Read more →

Absorption oil is a light liquid hydrocarbon used to remove heavier hydrocarbon components from a wet natural gas stream by intimate contact between the liquid and gas phases inside an absorption tower (absorber… Read more →

The term abyssal refers to the depositional environment of the deepest areas of the ocean basins, commonly called the abyss. Water depths exceed 2,000 m (6,562 ft) in the abyssal zone, with the abyssal plain typically… Read more →

What Is an Accelerator? An accelerator is a downhole drilling tool placed immediately above a jar in a bottom hole assembly (BHA) or fishing string to amplify the jar's impact force. The tool stores elastic energy via… Read more →

An accelerometer is a transducer that measures the acceleration of a body or the acceleration component of gravity acting along a defined axis. In the upstream oil and gas industry, accelerometers serve two distinct but… Read more →

Accommodation is a fundamental concept in sequence stratigraphy referring to the space available for sediment to accumulate and be preserved below the base level. More precisely, accommodation is the three-dimensional… Read more →

Accretion is the mechanism by which partially hydrated drill cuttings adhere to components of the bottomhole assembly (BHA) and accumulate as a compacted, layered deposit. Reactive clay minerals in the cuttings absorb… Read more →

A petroleum accumulation is a naturally occurring concentration of hydrocarbons trapped in porous reservoir rock in sufficient quantity to be detected, evaluated, and potentially produced. More precisely, an… Read more →

What Is an Accumulator? An accumulator stores high-pressure hydraulic energy in a nitrogen-precharged pressure vessel and delivers that energy instantaneously to close blowout preventer components during well control… Read more →

Accuracy describes the closeness of agreement between a measured value and the true (or conventionally accepted reference) value of the quantity being measured. In the oil and gas industry, accuracy is a formal… Read more →

(noun) A weak organic acid with the chemical formula CH₃COOH, used in oilfield operations as a low-corrosivity stimulation fluid for dissolving carbonate scale and calcium carbonate formations, as a pH buffer in… Read more →

A generic term used to describe a treatment fluid typically comprising hydrochloric acid and a blend of acid additives. Acid treatments are commonly designed to include a range of acid types or blends, such as acetic,… Read more →

The acid effect refers to the measurable change in a pulsed neutron capture (PNC) log response that results directly from acidizing a carbonate formation. When acid is pumped into the near-wellbore zone, it dissolves… Read more →

What Is Acid Frac? Acid fracturing applies hydraulic pressure above fracture gradient in carbonate formations while injecting hydrochloric acid, which differentially dissolves the fracture faces to create a rough,… Read more →

What Is Acid Gas? Acid gas describes any gas component that dissolves in water to produce an acidic solution; in the oil and gas industry, the term refers primarily to hydrogen sulfide (H2S) and carbon dioxide (CO2),… Read more →

What Is an Acid Inhibitor? An acid inhibitor is a chemical additive blended into acid treatment fluids, including hydrochloric acid (HCl), hydrofluoric/hydrochloric acid (HF/HCl mud acid), and organic acids, to suppress… Read more →

The acid number is a standardized laboratory measurement that quantifies the total concentration of acidic components dissolved in a crude oil or petroleum product. Expressed in milligrams of potassium hydroxide per… Read more →

An acid tank is a purpose-built vessel used to transport raw or concentrated acid from a blending or manufacturing facility to the wellsite, where it will be used in a stimulation treatment such as matrix acidizing or… Read more →

What Is an Acid Wash? An acid wash is a targeted wellbore treatment in which a small volume of acid solution, typically 1 to 5 barrels (0.16 to 0.79 cubic meters), is circulated or spotted across perforations,… Read more →

What Is Acidizing? Acidizing pumps acid solutions into the wellbore and surrounding formation to dissolve damaging materials, remove near-wellbore scale or mineral fines, and restore or enhance hydrocarbon flow by… Read more →

In petroleum geophysics and well logging, acoustic refers specifically to compressional wave (P-wave) phenomena in which energy is transmitted as pressure pulses through a medium, independent of shear forces. The term… Read more →

Acoustic basement is the depth below which seismic energy cannot penetrate far enough to image coherent subsurface reflections, effectively defining the lower limit of the seismically resolvable stratigraphic column.… Read more →

An acoustic coupler is an electromechanical transducer device that converts acoustic (sound) signals into electrical signals, and electrical signals back into acoustic form, enabling the transmission of data over… Read more →