Oil and Gas Terms Beginning with “F” — Page 6

A chemical additive that alters fluid rheological properties to reduce friction created within the fluid as it flows through small-diameter tubulars or similar restrictions. Generally polymers, or similar friction… Read more →

An in-situ measurement of the flow profile made by pumping different fluids down the tubing and casing and observing the interface between them. The fluids are normally both water, but one may be fresh and the other… Read more →

A chemical additive used to control the loss of fluid to the formation through filtration. In cementing operations, loss of the aqueous phase can severely affect the performance of the slurry and set cement. In almost… Read more →

The act or means of controlling (usually lowering) the volume of filtrate that passes through a filter medium. Control of fluid loss for a mud is achieved by several means, one of which is by addition of… Read more →

A group of mud additives specifically designed to lower the volume of filtrate that passes through a filter medium. Specific materials are available for all types of water- and oil-base mud systems and are evaluated in… Read more →

An acid mixture that generates more hydrofluoric [HF] acid as the HF is consumed. In the field, fluoboric acid [HBF4] is easily prepared by mixing boric acid [H3BO3], ammonium bifluoride [NH3F.HF] and hydrochloric acid.… Read more →

A technique for imaging a core by moving a core between a source of X-rays and a fluorescent screen. The image on the screen is intensified and recorded by a video camera. Read more →

A type of tubing connection in which the internal or external surfaces are the same diameter throughout the tubing joint. Internal flush joints are most common, offering no restriction to fluid flow. Externally flush… Read more →

A high flow rate reached with a new well. Read more →

The volume close to the borehole wall in which all of the moveable fluids have been displaced by mudfiltrate. The flushed zone contains filtrate and the remaining hydrocarbons, the percentage of the former being the… Read more →

The fraction of water in a given pore space in the flushed zone. It is expressed in volume/volume, percent or saturation units and is given the symbol Sxo. Unless otherwise stated, the pore space concerned is usually… Read more →

Pertaining to an environment of deposition by a river or running water. Fluvial deposits tend to be well sorted, especially in comparison with alluvial deposits, because of the relatively steady transport provided by… Read more →

A distortion of the magnetic flux that has been introduced into a casing by a low-frequency electromagnet or permanent magnet. The principle of flux leakage is used to detect casing corrosion, since flux leakage is… Read more →

The noncombustible residue from the burning of pulverized coal. Fly ash is pozzolanic and is frequently used to replace a portion of the cement and reduce its density. Read more →

The use of foam as a diverting agent during staged stimulation treatments. Stable foam is relatively viscous and the effect within a reservoirmatrix can be used to divert subsequent acid stages from the zones already… Read more →

An enhanced oil recovery process in which foam is injected into a reservoir to improve the sweep efficiency of a driving fluid. Foam can be generated either in the reservoir pore space or at the surface before… Read more →

A device fitted in surface treatment lines that helps distribute a liquid foamer phase in a stream of nitrogen gas. The foam generator creates a consistent mixture that becomes a stable foam under downhole pressure and… Read more →

A homogeneous, ultralightweight cement system consisting of base cement slurry, gas (usually nitrogen) and surfactants. Foamed cements are commonly used to cement wells that penetrate weak rocks or formations with low… Read more →

An additive used in preparation of foam used as a drilling fluid. Drilling foam is water containing air or gas bubbles, much like shaving foam, and it must withstand high salinity, hard water, solids, entrained oil and… Read more →

An oil-continuous foam that contains dispersed gas bubbles produced at the wellhead from heavy oil reservoirs under solution gas drive. The nature of the gas dispersions in oil distinguishes foamy oil behavior from… Read more →

A measure of the redundancy of common midpointseismic data, equal to the number of offset receivers that record a given data point or in a given bin and are added during stacking to produce a single trace. Typical… Read more →

Variations in the properties of seismic data, encountered during processing, that are related to the acquisition geometry and distort the amplitude and phase of reflections. Also called acquisition footprint. Read more →

The amount of foreign personnel, material and services that working interest owners are permitted to employ, as defined under the terms of a concession when drilling and operating a well. Read more →

The simplest aldehyde, having the formula HCHO. Formaldehyde is used in aqueous solutions as a preservative. In muds, paraformaldehyde is added to protect against bacterial attack. The formaldehyde test determines the… Read more →

A class of salts made from neutralization of formic acid with a metal hydroxide or oxide. Three alkali-metal formates are used in drilling, drill-in and completion fluids, (1) sodium formate, HCOO-Na+, (2) potassium… Read more →

A general term for the rock around the borehole. In the context of formation evaluation, the term refers to the volume of rock seen by a measurement made in the borehole, as in a log or a well test. These measurements… Read more →

What Is Formation Damage in Oil and Gas? Formation damage is any reduction in the intrinsic permeability of a reservoir rock near the wellbore caused by drilling, completion, production, or injection operations. It… Read more →

The measurement and analysis of formation and fluid properties through examination of formation cuttings or through the use of tools integrated into the bottomhole assembly while drilling, or conveyed on wireline or… Read more →

The time that has elapsed between the bit first penetrating a formation and a log being recorded opposite the formation. In logging-while-drilling operations, this time is different for each log, since it depends on the… Read more →

What Is Formation Factor? The formation factor (F) is a dimensionless petrophysical parameter that relates the electrical resistivity of a fully water-saturated rock to the resistivity of the water it contains: F = R₀ /… Read more →