Discover the IHRDC Energy Glossary_beta

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M

MBBL

One thousand barrels of crude oil, bitumen, condensate or natural gas liquids.

MCF

One thousand standard cubic feet of natural gas. In the United States, standard conditions are defined as gas at 14.7 psia and 60oF.

MFFI

The free fluid index in NMR log interpretation. In Halliburton's terminology, MFFI has been used as the abbreviation for the free fluid index.

MMBBL

One million barrels of crude oil, bitumen, condensate or natural gas liquids.

MMCF

One million standard cubic feet of natural gas. In the United States, standard conditions are defined as gas at 14.7 psia and 60oF.

MMSCF

One million standard cubic feet of gas. (One cubic foot of gas at 60°F (15°C) and atmospheric pressure.)

MMSCFD

Measurement of natural gas equaling "one million standard cubic feet perday."

MODBUS Protocol

A standard communications protocol that governs the transmission of data through networks

MON

Motor octane number; indicates gasoline performance under severe operating conditions.

MPHI

MPHI is the effective porosity derived from NMR log interpretation.

A proprietary, computer-based petrophysical analysis developed by NUMAR that uses MRIL measurements to augment conventional resistivity and porosity logs within a Dual Water petrophysical interpretation model.

MSCFD

Measurement of natural gas equaling "one thousand standard cubic feet perday."

MSD signs

Objective findings that an MSD is present including decreased range of motion, decreased grip strength, loss of muscle function and, in the most severe cases, even deformity.

MSD symptoms

Physical indications that an employee may be developing an MSD. They include numbness, burning, an ache or pain, tingling, cramping and stiffness.

MSIG

MSIG is the total porosity from NMR log interpretation.

MTPA

Millions of tonnes per annum.

Machine

A device that uses applied forces advantageously to perform work

Magnetic Controller

A motor controller in which control functions are performed by electromagnetic switches

Magnetic Field

A portion of space or area within which magnetic forces produced by a magnet or a current-carrying conductor can be detected; the lines of force surrounding a permanent magnet or a moving charged particle.

Magnetic Moment

Magnetic moment is the property of a magnet that interacts with an applied field to give a mechanical moment.

Magnetic Overload Device

A type of overload device that operates on the magnetic field produced by current

Magnetic Pickup

A feedback device that senses the movement of motor shafts or machinery parts and provides a feedback signal to a variable speed controller

Magnetic Resonance

Magnetic resonance is a phenomenon by which a nucleus absorbs electromagnetic radiation of a specific frequency in the presence of a strong magnetic field.

Magnetic Resonance Imaging Log (MRIL)

The Magnetic Resonance Imaging Log (MRIL) is the proprietary nuclear magnetic resonance (NMR) logging service developed by Numar, a company subsequently bought by Halliburton.

Magnetic lines of flux

Lines used to represent a magnetic field.

Magnetism

How materials respond on the microscopic level to an applied magnetic field; to categorize the magnetic phase of a material.

Magnetizing Current

Current required by an induction motor; used to create a magnetic field in the motor.

Magnetometer

An instrument used for measuring magnetic forces, especially the Earth's magnetism.

Magnetostrictive Material

A magnetostrictive material consists of tiny ferromagnets.

Main Steam Stop Valve

A specially designed, hydraulic cylinder operated valve that stops the flow of steam to the turbine to prevent possible damage.

Main Steam System

A system of pipes and valves that directs and controls the flow of steam from the boiler to the turbine.

Main fractionator

The area of a cat cracking unit where hot cracked gas from the reactor is separated into different fractions.

Makeup Water

Water added to a cooling tower's catch basin to maintain the proper level

Makeup Water System

The support system that adds water to the steam cycle to replace water and steam lost as a result of leakage

Makeup catalyst

Catalyst that is continually added to maintain desired yields and conversion and to make up for catalyst lost in the cracking process.

Malaria

A disease caused by a parasitic protozoan that is usually transferred to the human bloodstream by a mosquito. It is characterized by attacks of chills, fever and sweating. Malaria destroys red blood cells.

Male-female ﬂange

A ﬂange similar to the tongue-and-groove. The female part of one ﬂange half is formed in a raised area around the center opening into which the male part of the other ﬂange half ﬁts.

Mallet

A short-handed hammer, usually with a cylindrical wooden, rubber, plastic, or rawhide head, used for striking a chisel

Mandatory Training (formerly known as Compliance)

A function in CMS Online used to assign and track required training across all business locations and functions. Certain training, such as Health, Environment and Safety courses, may be required by the organization, and in some cases may be required as a result of government mandate.

Mandrel

A bar, shaft, spindle, or tapered tool around which other components are arranged or assembled. In riveting, the shank of a rivet.

Manifold

A system of tubing attached to the main pipe that may divide flow, combine flows or reroute a flow.

Manipulated Variable

The variable in a process that is adjusted or manipulated by the final control element to keep the controlled variable at set point.

Manometer

A basic instrument used to measure and indicate pressure or vacuum in terms of the height of a column of liquid

Manometers

Instruments that are used to measure condenser vacuum

Manual Control

A basic form of process control in which an operator monitors process variables and then makes manual adjustments to an output device to modify the process

Manual Trip

A mechanism that allows operators to stop, or trip, a system manually

Manway

A covered access port on a tank that can be opened to allow workers to enter the tank for cleaning, repairs, and inspections; also called a manhole.

Marine Sedimentary Rock

Marine sedimentary rock is any deposit of insoluble material transported from land areas to the ocean by wind, ice and rivers, as well as the remains of marine organisms, products of submarine volcanism and chemical precipitates from seawater that accumulates on the seafloor.

Markings

Labelling information that is printed on packaging to identify the contents of the packaging.

Markov Model

A Markov model is a stochastic method for randomly changing systems where it is assumed that future states do not depend on past states.

Mask

A pattern of bits (often expressed in hexadecimal) that acts as a filter to determine which bits in a data word are used or acted upon by an instruction.

Mass

The amount of matter an object possesses. In measurement, the weight of a product corrected for air buoyancy.

Mass Measurement

A method for measuring the quantity of NGLs by multiplying volume by density without needing to correct for temperature and pressure.

Mass Spectrometer

An analytical device that measures and identifies components in a multi-component mixture by measuring the deflection of ionized particles as they pass through a magnetic field

Mast

A movable support structure on some types of cranes that provides a connection point for the boom pendant lines and boom hoist lines

Master Calibration

Master calibration is the regular calibration of a logging tool in the workshop, usually monthly or quarterly. These are run to ensure that the tool is operating within the tolerances of the calibration coefficients from the primary calibration.

Master Meter Factor

The calibrated number of pulses per unit volume.

Master Meter Prover

A meter, usually a turbine meter, which is used to check the measuring accuracy of a NGL meter.

Mastery (Competency Level 4)

Has thorough understanding of activity or process / Has detailed knowledge of the industry standards, trends and best practices / Is regarded as an expert and final decision-maker / Develops new procedures, modifies existing methods and sets policy / Manages team and coordinates work

Material Safety Data Sheet

A document that identifies a specific material and provides information on exposure limits, physical and chemical characteristics, the nature of hazards, precautions for safe handling and use, protective equipment requirements, first aid procedures, storage and handling precautions, and spill/leak/disposal practices.

Material Safety Data Sheet (MSDS)

A document containing information about the identity of a hazardous material, its physical and chemical characteristics, the nature of its hazards, safe handling procedures, health effects and treatment, clean-up instructions, and other safety information.

Material balancing

A method of calculating how much of each raw material is needed to produce a desired product.

Matrix

In catalysis, materials that support zeolite crystals and provide shape and bulk to a catalyst particle. In geology, the finer-grained mass of material in which larger grains, crystals, or clasts are embedded within a rock.

Matrix Density, Grain Density

Matrix, or grain, density is the density of the minerals forming a rock, often referred to in core analysis as grain density.

Matrix Porosity

The porosity determined from a small sample of a rock core, in contrast to total porosity, where the whole core is used.

Matter

Anything that has weight (mass) and occupies space.

Maximum Fork Height

The distance from the floor to the forks of a forklift when the forks are raised to full mast extension

Maximum Operating Temperature

The highest final operating temperature at which a conductor can operate without overheating

Maximum Working Pressure (MWP)

The maximum pressure the compressor can handle while operating continuously.

Maximum boiling point azeotrope

An azeotrope that boils at a temperature that is above the boiling points of its components.

Maximum peak output voltage

The maximum peak-to-peak output voltage that can be obtained without clipping when the op-amp is operated from a bipolar supply.

Maximum-output-swing

The range of frequencies within which the maximum output voltage swing is above a specified value or the maximum frequency of an amplifier in which the output amplitude is at the extents of its linear range. Also called full power bandwidth.

Mean Cell Residence Time

The amount of time that the average micro-organism, or bug, spends in an activated sludge system before it is removed

Mean Square Dip (MSD)

Mean square dip (MSD) uses all 28 possible cross correlations from an eight curve dipmeter tool to compute 28 displacements.

Measured Variable

The physical quantity, property, or condition that is measured to determine the actual condition of a controlled variable

Measurement While Drilling

Measurements taken downhole with an electromechanical device located in the bottom hole assembly. All MWD systems typically have three major subcomponents: power system, telemetry system, and directional sensor.

Mechanical Connector or Terminal

A connector or terminal that is installed by tightening a bolt or setscrew to clamp the connector or terminal onto a conductor

Mechanical Float Switch

In a single-point level detection system, an electrical switch that is operated by the mechanical action of a linkage and a float rod.

Mechanical Interlock

An arrangement of components intended to prevent energizing an electrical device in a way that could damage it or that could be unsafe

Mechanical Operator

An electric, hydraulic, or pneumatic device that is used to open and close a valve

Mechanical Seal

A device composed of a rotating element and a stationary element used to seal between a rotating shaft and a stationary housing (such as a pump casing) with virtually no leakoff.

Mechanical advantage

The advantage gained in transmitting force through the use of a machine; the ratio between resistance force and applied force.

Mechanical-draft Cooling Tower

A cooling tower in which air is moved through the tower by fans

Media

The physical connection or cable used for PLC network connections between nodes on a network.

Medical consultation

A consultation that takes place between an employee and a licensed physician for the purpose of determining what medical examinations or procedures, if any, are appropriate in cases where a significant exposure to a hazardous chemical may have taken place.

Megahertz

1,000,000 hertz; a unit of frequency

Megawatt (MW)

One million watts.

Megawatt-Hour (MWh)

One million watt-hours.

Megger

A trademarked term commonly used to indicate the procedure of measuring the insulation resistance of a motors windings

Membrane Potential

The electromagnetic force generated across an ion-selective membrane when solutions on either side of the membrane have different salinities.

Memory Map

A graphical representation of the memory model of a microprocessor

Memory gauge investigations

Memory gauge investigation refers to memory operations that store the acquired data/images for later review, as opposed to real-time operations when the data/image is immediately available for review.

Meniscus

The curve in the upper surface of a liquid close to the surface of the container or another object, caused by surface tension. It can be either convex or concave, depending on the liquid and the surface.

Mental lift

A planning session in which the load's size, weight, contents, location, and destination are considered before the load is lifted.

Mentor

A person assigned to assist an employee with their professional development. Based on the Competency Development Plan configuration chosen by the client, the Mentor can play a role in building and/or assessing the plan.

Mentoring

Matches a trainee with an experienced individual from outside the employee's supervisory chain to provide guidance to enhance the personal and professional growth of the employee. See also, Coaching

Mercaptan (RSH)

A slightly acidic organic compound containing sulfur and hydrogen.

Mercury Switch

A switch consisting of a glass vial that contains a pool of mercury and a set of contacts; a circuit is completed when the mercury covers the contacts and broken when the vial tips and the mercury no longer covers the contacts.

Metal oxide semiconductor field effect transistor

A type of IGFET that has a gate that is insulated from the transistor body by a thin layer of metal oxide.

Metal oxides

Contain a metal cation and the oxide anion 02.

Meter Factor

The correction to volume measurement attributable to variations in fluid viscosity, flow rate or meter wear.

Meter Movement

The device in an analog display that converts the flow of current into the mechanical motion of the pointer

Meter Proving

The process of checking a flow meter against another calibrated device, either a prover or master meter.

Meter Range

The pressure, temperature and viscosity variation specified for a meter by the manufacturer.

Meter Witnessing

The process of being present when an orifice meter is being checked and calibrated.

Meter-in Circuit

A flow control circuit that controls the amount of fluid going to an actuator by restricting flow directly between the pump and the actuator

Meter-out Circuit

A flow control circuit that controls the amount of fluid returning from an actuator

Meth

A prefix for the name of a hydrocarbon that has one carbon atom.

Methane

A one-carbon compound (CH4) in which the carbon is attached by single bonds to four hydrogen atoms. It is a colorless, odorless, non-toxic but flammable light gaseous paraffin hydrocarbon that is the chief component of natural gas.

Methanol

A liquid alcohol injectant used for three purposes: To dissolve hydrates, to inhibit hydrate formation and to remove water from a natural gas stream.

Metric

A standard against which results can be measured.

Metric system

The world standard system of measurements in which all units are multiples of ten; includes meters, centimeters, and millimeters

Mho

A basic unit of electrical conductivity, the reciprocal of an ohm, used to describe a substance's ability to conduct current. Usually expressed in readings as micromhos.

Mica

The mica group of sheet silicate (phyllosilicate) minerals includes several closely related materials having nearly perfect basal cleavage.

Micro Porosity, Microporosity, Micropores

A micro porous formation is one containing pores with diameters less than 2 nm.

Micro-organisms

Extremely small plants and animals, such as algae and bacteria, that can contaminate water systems including cooling towers.

Micro-porosity

Micro-porosity is that part of the pore space that has a characteristic dimension less than 1 micron.

Microfossil

A fossil or fossil fragment that can only be seen with a microscope; the preserved remains or traces of animals, plants, and other organisms visible only under magnification.

Microgal

The microgal, (\( \mu \)gal), is one millionth of a gal.

Microlearning

Delivers targeted right-sized nuggets of information when and where employees need and want it. It can take different forms, from text to interactive multimedia. Smaller learning sessions provide all the information necessary for learners to achieve a specific training objective quickly, making microlearning valuable in business contexts.

Micrometer

A type of precision caliper used for making accurate measurements to the nearest thousandth or ten-thousandth, using a combination of a fixed scale and a rotating scale.

Microorganism

Any organism too small to be viewed by the unaided eye, such as bacteria, protozoa, and some fungi and algae.

Micropalaeontology

Micropalaeontology is the study of very small fossils under a microscope.

Microresistivity

Microresistivity is the resistivity related to the flushed/invaded zone immediately adjacent to the borehole wall.

Microresistivity, Micro Resistivity

Microresistivity is related to a log of the resistivity of the flushed zone recorded by a wireline electrode device. The device is mounted on a pad and pressed against the borehole wall. Several designs exist, for example microlog, microlaterolog, proximity log, microspherically focused log.

Microresistivity, Micro Resistivity, Micro-resistivity

Microsecond

A unit of time equivalent to 0.000001 seconds

Microspheres

Extremely fine particles that make up the catalyst used for fluid catalytic cracking.

Microwave

A microwave is an electromagnetic wave with a wavelength in the range 0.001–0.3 m, shorter than that of a normal radio wave but longer than those of infrared radiation.

Microwave Channel

A transfer trip communication channel that uses microwaves to send transfer trip signals from one substation to another

Mill, Milled

A mill is a tool that grinds metal downhole. A mill is usually used to remove junk in the hole.

Milliampere (mA)

One thousandth an ampere.

Millidarcy

One thousandth of a darcy (10⁻³ darcy).

Milling

A process that uses a mill or similar downhole tool to cut and remove material from equipment or tools located in the wellbore.

Millisecond

A unit of time equivalent to 0.001 seconds

Mineral, Mineralogy, Mineralogical

A mineral is a naturally occurring substance that is solid and inorganic representable by a chemical formula, usually abiogenic, and has an ordered atomic structure. It is different from a rock, which can be an aggregate of minerals or non-minerals and does not have a specific chemical composition.

Minimum Horizontal Stress

Minimum horizontal stress is one of the principal stresses that confined underground formations are subjected to. Hydraulic fracture propagates perpendicular to the minimum principal stress.

Minimum boiling point azeotrope

An azeotrope that boils at a temperature that is below the boiling points of its components.

Mist Extractor

A device in the separator, usually of woven wire mesh, which re-moves liquid mist from the gas.

Mixed number

A number that consists of a whole number and a fraction.

Mixing box

A device used in double-duct ventilation systems to mix air coming from warm air ducts and cold air ducts.

Mnemonic

A simple abbreviation for a PLC instruction that is often somewhat descriptive. For example, "TON" for Timer: On-Delay.

Mobility

The ratio of effective permeability to phase viscosity. The overall mobility is the sum of individual phase mobilities. Well productivity is directly proportional to the product of mobility and layer thickness.

Mobility Ratio

The mobility of an injectant divided by that of the fluid it is displacing. A comparison of the ability of one fluid to move through or displace another fluid.

Moisture

A measure of the amount of water absorbed by a solid material

Molded-case Circuit Breaker

A circuit breaker that is fully enclosed in an insulated housing.

Mole

The fundamental unit of mass for a substance usually expressed in grams. Often shortened to mol.

Molecular Sieve Bed

A vertical vessel filled with solid desiccant pellets for dehydrating a natural gas stream.

Molecule

The smallest particle of a substance that retains all of the properties of that substance.

Mono-conductor cable

Mono-conductor cables, with a typical diameter of around 1/4 inch, are mostly used for well completion services, such as firing perforating guns or setting wireline packers and plugs, and for basic production logging surveys, such as flowmeters and temperature logs in hydrocarbon producing wells.

Monoethanolamine (MEA)

A type of amine that consists of one nitrogen atom, two hydrogen atoms, and an ethanol molecule.

Monomer

A small, individual molecule that is used to make a polymer chain.

Monopole Sonic Tool Excitation

In monopole excitation, the sonic logging tool's transmitter emits acoustic energy uniformly around the tool. In fast formations, this energy excites three waves that travel down the borehole wall: Compressional; Shear; Stoneley waves.

Monostable Multivibrator

A multivibrator that has one stable state.

Montmorillonite

A very soft phyllosilicate group of minerals that typically form in microscopic crystals, forming a clay. A member of the smectite group, it is a 2:1 clay with 2 tetrahedral sheets sandwiching a central octahedral sheet. The particles are plate-shaped with an average diameter around 1 μm.

Moorings

Lines that are used to secure a barge to a dock during a transfer.

Motion

A body changing position

Motor Action

The movement of an object that results from the interaction of two magnetic fields

Motor Branch Circuit

A circuit that provides power and protection for a particular motor

Motor Control Center

A common housing in which several motor controllers and other electrical devices are grouped together. Also called a switch rack.

Motor Controller

A device or group of devices whose purpose is to control and protect a motor

Motor Operator

A motor-driven assembly used to position a valve electrically by the use of gearing

Motor Starter

A large relay designed for controlling power to a motor; also called a contactor

Moving R chart

A chart for which the value of each plotted point is calculated by subtracting the smallest value from the largest value of a specific number of the most recent samples

Moving X-bar chart

A chart for which the value of each plotted point is calculated by averaging the values of a specific number of the most recent samples

Mucous membranes

A lubricating membrane lining an internal surface or an organ, such as the mouth, throat, eyes, nasal passages and wind pipe.

Mud Cake

Mud cake is the residue deposited on a permeable rock when a drilling fluid is forced against the borehole wall under a differential pressure.

Mud Cake, Filter Cake

Mud cake, also termed filter cake, is the residue deposited on a permeable rock when a drilling fluid is forced against the borehole wall under a differential pressure.

Mud Filtrate

The liquid that passes through a filter cake from a slurry held against the filter medium, driven by differential pressure. Both dynamic and static filtration can produce a filtrate.

Mud Log

A detailed record (a well log) of a borehole generated by examining the cuttings of rock, associated gases, and hydrocarbon fluorescence brought to the surface by the circulating drilling mud. It typically denotes rock formation properties, associated gases, and hydrocarbon fluorescence for cuttings at specified intervals.

Mud Logging

The process whereby circulating drilling mud and its associated drill cuttings and gas are continuously monitored as the well is being drilled, and findings are documented in a mud log.

Mud Pulse Telemetry

A method of transmitting LWD and MWD data acquired downhole to the surface using pressure pulses in the mud system. The measurements are usually converted into an amplitude- or frequency-modulated pattern of mud pulses. The same telemetry system is used to transmit commands from the surface.

Mudstone

A type of mud rock; a fine-grained sedimentary rock whose original constituents were clays or muds. Grain size is up to 0.0625 mm (0.0025 in), with individual grains too small to be distinguished without a microscope.

Multi-Mineral Analysis

Multi-mineral analysis methods emphasise the mineral content of the formation rocks. Such log analysis techniques are often based on a probabilistic, or optimizing, approach to modeling wireline and rock data.

Multi-Pass Heat Exchanger

A heat exchanger in which one or both fluids pass through more than once.

Multi-Stage Compressor

A compressor which has two or more cylinders to compress gas in stages from low pressure to high pressure.

Multi-conductor Wireline Logging Cable, Multi-conductor Cable

Seven (7)-conductor wireline is the standard for open hole logging. It is better than a single conductor cable for supplying power to the tools and for electrical communications.

Multi-lateral Well

A multilateral well is a well that has more than one branch radiating from the main wellbore.

Multi-mineral

Multi-mineral is a situation where there is more than one mineral present.

Multi-mode Fiber

Common 62.5/125 fiber that can use inexpensive, low power, LEDs as transmitting light sources but has a range of about two kilometers due to pulse distortion

Multi-shot Reclosing

A reclosing relay that recloses a circuit breaker several times; the first reclose is usually instantaneous, and can be followed by up to two or three delayed recloses

Multiconductor Cable

A cable that consists of a group of conductors that are insulated from one another

Multicore Solder

Solder that has flux embedded in it

Multidraw Tower

A distillation tower that separates a feed into more than two products; also called a side-draw tower

Multipart Valve

A valve that can route fluid flow through a number of different openings, or ports

Multiple Loop Control

A type of process control in which more than one process loop is controlled by a single controller. Each loop includes its own inputs, setpoints, control algorithms, and outputs.

Multiplication Component

A control device in which the output is the product of two inputs

Multiport Valve

A valve that can route fluid flow through a number of different openings, or ports

Multivibrator

An RC oscillator that has two amplifier stages and produces non-sinusoidal signals. The frequency of the signals is determined by resistance and capacitance rather than by inductance and capacitance.

Musculoskeletal disorder (MSD)

Disorders of the muscles, nerves, tendons, ligaments, joints, cartilage, blood vessels and spinal discs. They may include muscle strains and tears, ligament sprains, joint and tendon inflammation, pinched nerves and spinal disc degeneration. Although MSDs can result from one-time incidents, more often than not they result from damage to the body that has accumulated over a period of time. These types of MSDs are also sometimes referred to as cumulative trauma disorders.

Mushrooming

A damage condition in which the striking surface of a tool, such as a chisel, is misshaped, creating a mushroom pattern

metamorphic

Metamorphic rocks are a category of rocks that arise from the transformation of existing rocks into new rock types, which are generated by high temperatures and pressures that cause profound physical or chemical changes and result in new textures and mineral compositions. Common metamorphic rocks include schist, gneiss, slate, quartzite and marble.

micro-induction sensors

A micro-induction sensor is a device that uses the principle of electromagnetic induction (a current produced because of voltage production (electromotive force) resulting from a changing magnetic field) to detect or measure objects.

microfossils

Microfossils are fossils or fragments that can only be seen with a microscope.

micrometers

1 meter = 1 million micrometers

micropaleontology

Micropaleontology is a branch of paleontology that studies microfossils, fossils so tiny a microscope must be used to view them.

mineral staining

Mineral staining is the discoloration of a sample's surface by the presence or reaction of minerals and fluids in the subsurface.

monomineralic

Monomineralic refers to rocks composed primarily of a single mineral, such as rock salt (halite), limestone (calcite), and quartzite (quartz).

mouth bar

Mouth bars are part of a deltaic system, typically referring to the mid-channel deposition of river-transported sediment at the river's mouth.

mud logger

A mud logger is an oil and gas professional who collects samples of drill cuttings as a well is being drilled. These cuttings are usually taken from shale shakers. Mud loggers analyze these samples to identify the rock types and their properties, determine the presence of hydrocarbons, and correlate them to depths in the well.

mud logging unit

A trailer or cabin at the wellsite (or a designated safe location near the shale shakers) that contains the special equipment and materials needed to collect, process, and evaluate drill cutting samples and analyze any gas contained in the returning drilling mud.

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MAWP