A – B – C – D – E – F – G – H – I – J – K – L – M – N – O – P – R – S – T – U – V – W – X
| MRBP | Magna Range Bridge Plug |
| MGL | Magnelog |
| MP | Magnetic particle |
| MPI | Magnetic particle inspection |
| NUMAR | Magnetic Resonance Image Log |
| MRIRE | Magnetic Resonance Image Report |
| MSS | Magnetic Single Shot |
| MAGST | Magnetostratigraphic Report |
| MT | Magnetotellurics |
| MCHE | Main Cryogenic Heat Exchanger |
| MP | Main Pass Area Gulf of Mexico leasing area |
| MHA | Major hazards analysis |
| MPD | Managed Pressure Drilling |
| MOC | Management of Change |
| MSC | Management system coordinator |
| MCS | Manifold & Connection System |
| MCM | Manifold Choke Module |
| MCP | Manifold compression platform |
| MPQT | Manufacturing Procedure Qualification Test |
| MPS | Manufacturing Procedure Specification |
| MARA | Maralog |
| MLF | Marine Loading Facility |
| MMO | Marine mammal observer |
| MOF | Marine Offloading Facility |
| MR | Marine Riser |
| MSRC | Marine Spill Response Corporation |
| MWS | Marine Warranty Survey |
| MWCC | Marine Well Containment Co. Partners in the nonprofit include BP, BHP Billiton, Apache Corp., Anadarko Petroleum, and Statoil. |
| MTSRU | Maritime Transportation System Recovery Unit |
| MQ | Marqesas Gulf of Mexico leasing area |
| MF | Marsh Funnel (mud viscosity) |
| MS | Mass spectrometry |
| MCS | Master Control Station |
| MSA | Master service agreement |
| MSC | Master services contract |
| MVB | Master Valve Block on Xmas Tree |
| MI | Matagorda Island Area Gulf of Mexico leasing area |
| MRR | Material Receipt Report |
| MSDS | Material Safety Data Sheets |
| MTO | Material Take Off |
| MTR | Material test reports |
| MOT | Materials/Marine Offloading Terminal |
| XPERM | Matrix Permeability in the X-Direction |
| MAASP | Maximum Acceptable (or Allowable) Annular Surface Pressure |
| MAOP | Maximum allowable operating pressure |
| MASP | Maximum allowable surface pressure |
| MAWOP | Maximum allowable wellhead operating pressure |
| MAWP | Maximum allowable working pressure |
| MASPcc | Maximum anticipated surface pressure for the completion case |
| MGW | Maximum gross weight |
| MIYP | Maximum Internal Yield Pressure |
| MSP | Maximum source pressure |
| Hmax | Maximum Wave Height |
| MSL | Mean sea level |
| MTBF | Mean Time Between Failure |
| MTTF | Mean time to failure |
| MD | Measured depth |
| MD | Measured Depth (see also MDSS) |
| MDSS | Measured Depth Sub-Sea |
| M&R | Measurement and regulation |
| MWD | Measurement while drilling |
| MWDRE | Measurement While Drilling Report |
| MD | Measurements/Drilling Log |
| MSI | Mechanical and Structural Inspection |
| MCD | Mechanical Completion Dossier |
| MEM | Mechanical earth model |
| MEIC | Mechanical Electrical Instrumentation Commission |
| MI | Mechanical integrity |
| MEPRL | Mechanical Properties Log |
| MSD | Mechanical setting devices |
| MSCT | Mechanical Sidewall Coring Tool |
| LD50 | Median lethal dose |
| MJ | Megajoule |
| MOU | Memorandum of understanding |
| MERCR | Mercury Injection Study Report |
| MNP | Merge and Playback Log |
| MERG | Merge FDC/CNL/Gamma Ray/Dual Laterolog/Micro SFL Log |
| MPK | Merged Playback Log |
| mKB | Meters below Kelly Bushing |
| C1 | methane |
| MDL | Methane Drainage Licence (United Kingdom), a type of onshore licence allowing natural gas to be collected “in the course of operations for making and keeping safe mines whether or not disused” |
| MH | Methane hydrate (methane clathrate, or fire ice) |
| MDEA | Methyl Diethanolamine (aMDEA) |
| MTBE | Methyl tertiary butyl ether |
| MBT | Methylene Blue Test |
| m | metre |
| MT | Metric tons |
| MA | Miami Gulf of Mexico leasing area |
| MSFL | Micro SFL Log; Micro-Spherically Focussed Log (resistivity). |
| MSL | Micro Spherical Log |
| MEST | Micro-electrical scanning tool (a dipmeter, aka. MST or FMS). |
| MLL | Microlaterolog |
| ML | Microlog, or Mud Log |
| MPA | Micropalaeo Analysis Report |
| MIPAL | Micropalaeo Log |
| MENA | Middle East and North Africa (region) |
| MWA | Military warning area |
| mD | millidarcy, measure of permeability, with units of area |
| mmHg | Millimeters of mercury (a unit of pressure) |
| MMboe | million barrels of oil equivalent |
| MMboed | million barrels of oil equivalent per day |
| MMbod | million barrels of oil per day |
| MMbd | million barrels per day |
| MMbpd | million barrels per day |
| MMbtu | Million btu |
| MMcfe | million cubic feet (of natural gas equivalent) |
| MMcf | million cubic feet (of natural gas) |
| MMTA | Million metric tons per annum |
| MMscf | Million standard cubic feet |
| mmscfd | million standard cubic feet per day |
| mmstb | million stock barrels |
| MMTPA | Millions of Metric Tonnes per Annum |
| MMS | Minerals Management Service, (United States) |
| MIFR | Mini Frac Log |
| MINL | Minilog |
| MBR | Minimum Bend Radius |
| MIST | Minimum Industry Safety Training |
| MS | Mississippi |
| MC | Mississippi Canyon Gulf of Mexico leasing area |
| MO | Mobile Gulf of Mexico leasing area |
| MODU | Mobile offshore drilling unit |
| MOPU | Mobile offshore production unit |
| MOU | Mobile offshore unit |
| MDT | Modular formation Dynamic Tester |
| MSIP | Modular Sonic Imaging Platform (Sonic Scanner) |
| MCC | Molded case circuit breaker |
| MEA | Monoethanolamine |
| MEG | Mono-Ethylene Glycol |
| MOM | Month on month |
| MR | Morning Report |
| MIRU | Move In and Rig Up |
| STARS | MSRC’s Spill Team Area Responders network of contractors |
| MST | MST EXP Resistivity Log |
| MTT | MTT Multi-Isotope Trace Tool |
| MLH | Mud Liner Hanger |
| MUD | Mud Log |
| MUDT | Mud Temperature Log |
| MW | Mud weight |
| MBWH | Multi Bowl Wellhead |
| MPV | Multi Purpose Vessel |
| MQC | Multi Quick Connection Plate |
| MRCV | Multi Reverse Circulating Valve |
| MSIPC | Multi Stage inflatable Packer Collar |
| MACL | Multiarm Caliper Log |
| MBRO | Multi-Bore Restriction Orifices |
| MFCT | Multifinger Calliper Tool |
| ML | Multilateral |
| MPFM | Multi-Phase Flow Meter |
| MPFM | Multiphase flowmeter |
| MPP | Multiphase Pump |
| MAC | Multipole Acoustic Log |
| MU | Mustang Island Area Gulf of Mexico leasing area |
| MuSol | Mutual Solvent |