Magnetic anomalies 338 Magnetic field 498 Magnetic field (in space) 339 Magnetic methods 424 Magnetic properties 390 Magnetic susceptibility 418 Magnetosphere 857 Mammalia 1,605 Mandibulata 1,525 Mantle 450 Mapping 3,918 Maps 2,458 Maps and charts 507 Marine atmospheres 474 Marine biology 3,708 Marine deposits 4,095 Marine environment 4,884 Marine geology 1,470 Marine installations 708 Marine sedimentation 692 Marine sediments 3,355 Marine transportation 575 Mars 1,060 Mars (planet) 1,351 Mass balance 3,057 Mass movements 3,584 Mass movements (geology) 3,675 Mass spectra 804 Mass transfer 944 Mathematical methods 1,476 Mathematical models 8,898 Meadow soils 356 Measurement 3,060 Measuring instruments 2,212 Mechanical properties 2,171 Mechanical tests 617 Meetings 1,821 Melting 2,195 Meltwater 5,511 Mesozoic 1,432 Metabolism 413 Metal ores 399 Metals 3,935 Metamorphic rocks 846 Metamorphism 426 Metamorphism (snow) 522 Meteorites 408 Meteorological data 1,666 Meteorological factors 1,597 Meteorological instruments 534 Meteorology 6,302 Meteorology--Instruments 679 Meteorology--Maps and charts 566 Meteorology--Models 985 Methane 1,119 Methods 674 Microbiology 2,256 Microclimatology 515 Microelement content 400 Microfossils 3,648 Microorganisms 851 Microstructure 658 Microwave methods 842 Microwaves 1,836 Migration 486 Military engineering 391 Military facilities 706 Military geology 508 Military operation 652 Mineral composition 988 Mineral exploration 358 Mineralogy 2,262 Minerals 642 Mining 1,505 Miocene 533 Miospores 1,336 Mires 777 Mitigation 1,605 Mixing 600 Models 10,501 Modern 897 Modern analogs 367 Moisture 1,612 Moisture transfer 469 Molecular energy levels 498 Molecular structure 1,144 Mollusca 929 Monitoring 2,798 Monitors 356 Monsoons 465 Monthly variations 371 Moraines 4,236 Morphology 1,046 Mosses 605 Motor vehicles 549 Mountain glaciers 2,326 Mountains 2,658 Mountain soils 648 Movement 690 Mudflows 671