m (logging) M3

MAASP

Macaroni String

Magma

Magnetic Basement (seismic)

Magnetometer

Main Bore

Major

Make Hole

Make-Up

Make A Trip

Maltene

Managed Pressure Drilling

Mandrel

Manifold

Maraseal

Marble

Marcit

Mare�s Tail (process facility)

Marginal Field

Marginally Consolidated

Marine Riser

Marker (circulation)

Marker (formation)

Marker Fossils

Marsh Funnel

Martensite

MASP

Mast (rig up)

Master Valve

Material Safety Data Sheet

Matrix

Matrix Acidizing

MAWP

Maximum Efficient Rate

Maximum Principal Stress

MBAL(tm)

MBD

MBPD

MBE (reservoir)

MBE (heavy oil)

MBT

Mcf

MCS

MD (frequently shown incorrectly as md)

MD

MDRT

MDT

Measurement While Drilling

Mechanical Filter

Mechanical Integrity Test

Mechanical Jar (wireline tools)

Medium Radius

MEG

Memory Logs

Memory Tool

Meniscus

MeOH

MEOR

MER

Mercaptan

Mercury Pore Measurement or Porosimetry

Mesh

Meshrite(tm)

Mesozoic

Metal-to-Metal Seal

Metallizing

Metamorphic

Meter Factor

Meter Slippage

Methane

Methanol

Metocean

Metric Ton

MFCT

MFE

MFP

MFT

MGal (seismic)

MGI

MGL

MI

MI (flooding)

Mica

Micelle

Micro Cement

Microbeads or Microballoons

Microgels

Microlaterlog

Micro Log

Microorganisms

Micro-Seismic

Microemulsion

Micron Rating

Micropolishing

Microporosity

Middle Distillates

Midstream (operations)

Migration (seismic)

Migration (fluids)

Mill

Mill Scale

Milli

Millidarcy

Milligal (seismic)

Milling

Millout Extension (packer)

Mils Per Year

Mineral

Mineraloid

Mineral Rights

Minerals Management Service

Mini Frac

Minimum Bend Radius

Minimum Principal Stress

Miocene

MIR

MIRU

Miscible

Miscible Gas Drive

Misfire

Mississippian

Mist Flow

MIT

MIT-IA

Mitigation

MIT- OA

MIT-T

Mixed Layer Clays

MJ

ML

MLT

MMbls

MMcf

MMH

MMO

MMS

MMscf (gas volume)

Mobility Ratio

Mobilize

MOC

Model D Packer

Modified Isochronal Test

MODU

Modular Perforating Gun

Modulus of Elasticity

MOE

Mohs Scale

Monkey Board

Monobore

Monocline

Monolayer

Monte Carlo Risk Assessment

Montmorillonite

Moon Pool

MOP (LWD)

Mosquito Bill

Motherbore

Mouse Hole

Moveout (seismic)

MPa

MPD

MPLT

MPY

Ms

MSA

MSA (regulations)

MSCF (gas volume)

MSDS

MSFL (logging)

MSV

MT

MTBE

MTBF

MTR

MTTF

MU

Mud

Mud Acid

Mud Anchor

Mud Balance (fluid density)

Mud Cake

Mud Cup

Mud Density

Mud Displacement Flush

Mud Engineer

Mud Filtrate

Mud Flow Through Screens

Mud Log

Mud Loss

Mud Logger

Mud Motor

Mud Pit

Mud Pit Level Indicator and Alarm

Mud Pulse

Mud Pump

Mud Tracer

Mud Up

Mud Weight

Mudstone

Mule Shoe

Multicomponent Seismic

Multi-Finger Caliper

Multi-Lateral

Multi-Phase Flow

Multiple Completion

Multi-Pointing

Multi-Stage Cementing

Mutual Solvent

MW

MWD

MWP

MWPT

Mylar(tm)

Mysid Shrimp

MZ