Oil and Gas Terms Beginning with “B”

A BBL (also written bbl , barrel, or oil barrel) is the standard unit of crude oil and petroleum product volume used throughout the international petroleum industry, defined as exactly 42 US gallons or 158.987 litres… Read more →

Background gas (abbreviated BGG or sometimes BG ) is the continuous, baseline concentration of hydrocarbon gases detected in the drilling fluid returns at the surface during mud logging operations, representing the… Read more →

A bottom hole assembly ( BHA ) is the lowermost section of the drill string, comprising the drill bit and all specialized tools and drill collars between the bit and the start of the drill pipe or heavyweight drill… Read more →

Bottomhole circulating temperature ( BHCT ) is the equilibrium temperature at the bottom of a wellbore (or at any specified depth of interest) during active circulation of drilling fluid, representing the thermal… Read more →

Bottomhole pressure ( BHP ) is the fluid pressure measured or calculated at a specified datum depth within the wellbore — typically at the mid-perforation depth, the producing formation top, or the total depth of the… Read more →

Bottomhole static temperature ( BHST ) is the true geothermal equilibrium temperature of the formation at a specified depth, measured or inferred after the wellbore has been shut in for sufficient time that the thermal… Read more →

Bottomhole temperature ( BHT ) is the temperature recorded by the maximum reading thermometer (MRT) housed in a wireline logging tool string at the time of a logging run — specifically, the highest temperature… Read more →

BLPD (barrels of liquid per day) is the total volumetric production rate of all liquid phases from a producing well or field facility: oil, produced water, and any liquid condensate that has dropped out of the gas… Read more →

In petroleum engineering and operations documentation, BM is an abbreviation used in at least three distinct technical contexts that share no direct relationship but appear in different sections of the same well record,… Read more →

Biochemical oxygen demand ( BOD ), sometimes called biological oxygen demand , is a measure of the quantity of dissolved oxygen consumed by microorganisms in a water sample over a defined time period (standardly 5 days… Read more →

BOP is the universally recognized oilfield abbreviation for blowout preventer — the high-pressure valve assembly installed on the wellhead to seal the wellbore if a kick develops into an uncontrolled well control event.… Read more →

The BOP stack (blowout preventer stack) is the complete assembly of high-pressure wellbore closure equipment mounted at the wellhead during drilling — combining multiple preventer bodies (annular, ram), connecting… Read more →

BOPD (barrels of oil per day) is the most commonly used volumetric production rate measurement for crude oil wells, expressing how many barrels (1 barrel = 0.158987 m³) of stock tank oil (oil at surface standard… Read more →

Basic sediment and water (BS&W), also written BS&W or abbreviated as "basic sediment" in older WCSB usage, is the measurement of the combined volume fraction of water (free water and emulsified water) and inorganic… Read more →

BTU adjustment in natural gas commerce is the contractual mechanism by which the energy billing for natural gas delivered through a pipeline or sold at a custody transfer point is corrected to reflect the actual heating… Read more →

BWOB (by weight of blend) in oilfield cementing is a concentration basis that expresses the mass of a dry additive as a percentage of the total mass of the dry blend, where the dry blend is the complete pre-mixed bulk… Read more →

BWOC (by weight of cement) in oilfield cementing is the API-standard concentration basis for expressing the quantity of a cement additive relative to the mass of neat cement in the slurry, defined as kilograms of… Read more →

BWOW (by weight of water) in oilfield cementing is a concentration basis that expresses the quantity of a liquid or dissolved additive as a mass percentage of the mix water used in the cement slurry, defined as… Read more →

BWPD (barrels of water per day) in WCSB oil and gas production operations is the standard volumetric rate unit for produced water, measured at surface conditions in Canadian and US oilfield practice as the volume of… Read more →

Backlash in drilling and oilfield mechanical systems is the amount of free play, clearance, or lost motion in a gear train, rotary drive, threaded coupling, or mechanical assembly that must be taken up before the… Read more →

Bale eyes are the circular load-bearing apertures machined or forged into the bails of drilling rig hoisting components, through which a pin, hook, or latch element passes to create a mechanical connection in the… Read more →

Bales (also commonly written as bails ) are the U-shaped, C-shaped, or loop-type high-strength steel members that serve as the primary structural connectors between hoisting and production components on drilling rigs… Read more →

Bayesian inference is a statistical framework for updating the probability of a hypothesis as new evidence becomes available, grounded in Bayes' theorem: P(H|D) = P(D|H) x P(H) / P(D), where P(H|D) is the posterior… Read more →

The Bayesian method is a statistical framework for updating probability estimates as new evidence is observed, combining prior knowledge about a parameter expressed as a probability distribution with the likelihood of… Read more →

Bayesian probability is the interpretation of probability as a quantified degree of belief or confidence that a proposition is true, updated by evidence according to Bayes' theorem. In contrast to the frequentist… Read more →

In Canadian petroleum industry usage, BC refers to British Columbia, the westernmost province of Canada and a significant hydrocarbon-producing jurisdiction whose petroleum sector is concentrated in the northeastern… Read more →

A Bcf (billion cubic feet) is a unit of natural gas volume equal to one billion (10^9) standard cubic feet (scf) measured at standard conditions of 60°F (15.56°C) and 14.696 psia (101.325 kPa). Bcf is the standard unit… Read more →

Bcf/d (billion cubic feet per day) is the standard unit of natural gas volumetric flow rate used to express pipeline deliverability, play-level production, LNG terminal throughput, national supply statistics, and major… Read more →

Bearden units of consistency (abbreviated Bc ) is the dimensionless measurement scale used to quantify the pumpability and rheological state of oilwell cement slurries during laboratory thickening-time testing conducted… Read more →

The Beaufort scale is an empirical wind force rating system using a dimensionless integer scale from 0 (calm, wind speed less than 1 knot or 0.5 m/s) to 12 (hurricane force, wind speed greater than 64 knots or 32.7 m/s)… Read more →