List of Science Areas included under 'Geophysical'

  300   ATMOSPHERIC COMPOSITION AND STRUCTURE
  305   Aerosols and particles (0345, 4801)
  310   Airglow and aurora
  312   Air/sea constituent fluxes (3339, 4504)
  315   Biosphere/atmosphere interactions
  317   Chemical kinetic and photochemical properties
  320   Cloud physics and chemistry
  322   Constituent sources and sinks
  325   Evolution of the atmosphere
  330   Geochemical cycles
  335   Ion chemistry of the atmosphere (2419, 2427)
  340   Middle atmosphere--composition and chemistry
  341   Middle atmosphere--constituent transport and chemistry (3334)
  342   Middle atmosphere--energy deposition
  343   Planetary atmospheres (5405, 5407, 5409, 5704, 5705, 5707)
  345   Pollution--urban and regional (0305)
  350   Pressure, density, and temperature
  355   Thermosphere--composition and chemistry
  358   Thermosphere--energy deposition
  360   Transmission and scattering of radiation
  365   Troposphere--composition and chemistry
  368   Troposphere--constituent transport and chemistry
  370   Volcanic effects (8409)
  394   Instruments and techniques
  399   General or miscellaneous
  
  400   BIOGEOSCIENCES (New category to be developed; check other
        categories for relevant subordinate terms)
  
  600   ELECTROMAGNETICS
  604   Antenna arrays
  609   Antennas
  614   Biological effects
  619   Electromagnetic theory
  624   Guided waves
  629   Inverse scattering
  634   Measurement and standards
  639   Nonlinear electromagnetics
  644   Numerical methods
  649   Optics
  654   Plasmas
  659   Random media and rough surfaces
  664   Reflectors and feeds
  669   Scattering and diffraction
  674   Signal processing and adaptive antennas
  679   Singularity expansion method
  684   Transient and time domain
  689   Wave propagation (4275)
  694   Instrumentation and techniques
  699   General or miscellaneous
  
  900   EXPLORATION GEOPHYSICS
  902   Computational methods, seismic
  903   Computational methods, potential fields
  905   Continental structures (8109, 8110)
  910   Data processing
  915   Downhole methods
  920   Gravity methods
  925   Magnetic and electrical methods
  930   Oceanic structures
  932   Radioactivity methods
  933   Remote sensing
  935   Seismic methods (3025)
  994   Instruments and techniques
  999   General or miscellaneous
  
 1000   GEOCHEMISTRY (New field, replaces Rock Chemistry)
 1010   Chemical evolution
 1015   Composition of the core
 1020   Composition of the crust
 1025   Composition of the mantle
 1030   Geochemical cycles (0330)
 1035   Geochronology
 1040   Isotopic composition/chemistry
 1045   Low-temperature geochemistry
 1050   Marine geochemistry (4835, 4850)
 1055   Organic geochemistry
 1060   Planetary geochemistry  (5405, 5410, 5704, 5709, 6005, 6008)
 1065   Trace elements (3670)
 1094   Instruments and techniques
 1099   General or miscellaneous
 
 1200   GEODESY AND GRAVITY
 1204   Control surveys
 1206   Crustal movements--interplate (8155)
 1208   Crustal movements--intraplate (8110)
 1210   Diurnal and subdiurnal rotational variations
 1212   Earth's interior--composition and state (8105)
 1213   Earth's interior--dynamics (8115, 8120)
 1214   Geopotential theory and determination
 1219   Local gravity anomalies and crustal structure
 1221   Lunar geodesy and gravity (6250)
 1223   Ocean/Earth/atmosphere interactions (3339)
 1224   Photogrammetry
 1227   Planetary geodesy and gravity (5420, 5714, 6019)
 1229   Reference systems
 1234   Regional and global gravity anomalies and Earth structure
 1236   Rheology of the lithosphere and mantle (8160)
 1239   Rotational variations
 1241   Satellite orbits
 1242   Seismic deformations (7205)
 1243   Space geodetic surveys
 1244   Standards and absolute measurements
 1247   Terrestrial reference systems
 1249   Tides--Earth
 1255   Tides--ocean (4560)
 1294   Instruments and techniques
 1299   General or miscellaneous
 
 1500   GEOMAGNETISM AND PALEOMAGNETISM
 1503   Archeomagnetism
 1505   Biomagnetism
 1507   Core processes (8115)
 1510   Dynamo theories
 1512   Environmental magnetism
 1513   Geomagnetic excursions
 1515   Geomagnetic induction
 1517   Magnetic anomaly modeling
 1518   Magnetic fabrics and anisotropy
 1519   Magnetic mineralogy and petrology
 1520   Magnetostratigraphy
 1521   Paleointensity
 1522   Paleomagnetic secular variation
 1525   Paleomagnetism applied to tectonics (regional, global)
 1527   Paleomagnetism applied to geologic processes
 1530   Rapid time variations
 1532   Reference fields (regional, global)
 1533   Remagnetization
 1535   Reversals (process, timescale, magnetostratigraphy)
 1540   Rock and mineral magnetism
 1545   Spatial variations (all harmonics and anomalies)
 1550   Spatial variations attributed to seafloor spreading (3005)
 1555   Time variations--diurnal to secular
 1560   Time variations--secular and long term
 1594   Instruments and techniques
 1599   General or miscellaneous
 
 1600   GLOBAL CHANGE (New category)
 1610   Atmosphere (0315, 0325)
 1615   Biogeochemical processes (4805)
 1620   Climate dynamics (3309)
 1625   Geomorphology and weathering (1824, 1886)
 1630   Impact phenomena
 1635   Oceans (4203)
 1640   Remote sensing
 1645   Solid Earth
 1650   Solar variability
 1655   Water cycles (1836)
 1694   Instruments and techniques
 1699   General or miscellaneous
 
 1700   HISTORY OF GEOPHYSICS
 1704   Atmospheric sciences
 1709   Geodesy
 1714   Geomagnetism and paleomagnetism
 1719   Hydrology
 1724   Ocean sciences
 1729   Planetology
 1734   Seismology
 1739   Solar/planetary relationships
 1744   Tectonophysics
 1749   Volcanology, geochemistry, and petrology
 1794   Instruments and techniques
 1799   General or miscellaneous
 
 1800   HYDROLOGY
 1803   Anthropogenic effects
 1806   Chemistry of fresh water
 1809   Desertification
 1812   Drought
 1815   Erosion and sedimentation
 1818   Evapotranspiration
 1821   Floods
 1823   Frozen ground
 1824   Geomorphology (1625)
 1827   Glaciology (1863)
 1829   Groundwater hydrology
 1831   Groundwater quality
 1832   Groundwater transport
 1833   Hydroclimatology
 1836   Hydrologic budget (1655)
 1842   Irrigation
 1845   Limnology
 1848   Networks
 1851   Plant ecology
 1854   Precipitation (3354)
 1857   Reservoirs (surface)
 1860   Runoff and streamflow
 1863   Snow and ice (1827)
 1866   Soil moisture
 1869   Stochastic processes
 1871   Surface water quality
 1875   Unsaturated zone
 1878   Water/energy interactions
 1884   Water supply
 1886   Weathering (1625)
 1890   Wetlands
 1894   Instruments and techniques
 1899   General or miscellaneous
 
 2100   INTERPLANETARY PHYSICS
 2102   Corotating streams
 2104   Cosmic rays
 2109   Discontinuities
 2111   Ejecta, driver gases, and magnetic clouds
 2114   Energetic particles, heliospheric (7514)
 2116   Energetic particles, planetary
 2118   Energetic particles, solar
 2124   Heliopause and solar wind termination
 2129   Interplanetary dust
 2134   Interplanetary magnetic fields
 2139   Interplanetary shocks
 2144   Interstellar gas
 2149   MHD waves and turbulence
 2151   Neutral particles
 2152   Pickup ions
 2154   Planetary bow shocks
 2159   Plasma waves and turbulence
 2162   Solar cycle variations (7536)
 2164   Solar wind plasma
 2169   Sources of the solar wind
 2194   Instruments and techniques
 2199   General or miscellaneous
 
 2400   IONOSPHERE
 2403   Active experiments
 2407   Auroral ionosphere (2704)
 2409   Current systems (2708)
 2411   Electric fields (2712)
 2415   Equatorial ionosphere
 2419   Ion chemistry and composition (0335)
 2423   Ionization mechanisms
 2427   Ionosphere/atmosphere interactions (0335)
 2431   Ionosphere/magnetosphere interactions (2736)
 2435   Ionospheric disturbances
 2437   Ionospheric dynamics
 2439   Ionospheric irregularities
 2443   Midlatitude ionosphere
 2447   Modeling and forecasting
 2451   Particle acceleration
 2455   Particle precipitation
 2459   Planetary ionospheres (5435, 5729, 6026, 6027, 6028)
 2463   Plasma convection
 2467   Plasma temperature and density
 2471   Plasma waves and instabilities
 2475   Polar cap ionosphere
 2479   Solar radiation and cosmic ray effects
 2481   Topside ionosphere
 2483   Wave/particle interactions
 2487   Wave propagation (6934)
 2494   Instruments and techniques
 2499   General or miscellaneous
 
 2700   MAGNETOSPHERIC PHYSICS
 2704   Auroral phenomena (2407)
 2708   Current systems (2409)
 2712   Electric fields (2411)
 2716   Energetic particles, precipitating
 2720   Energetic particles, trapped
 2722   Forecasting
 2724   Magnetopause, cusp, and boundary layers
 2728   Magnetosheath
 2730   Magnetosphere--inner
 2731   Magnetosphere--outer
 2732   Magnetosphere interactions with satellites and rings
 2736   Magnetosphere/ionosphere interactions
 2740   Magnetospheric configuration and dynamics
 2744   Magnetotail
 2748   Magnetotail boundary layers
 2752   MHD waves and instabilities
 2753   Numerical modeling
 2756   Planetary magnetospheres (5443, 5737, 6030)
 2760   Plasma convection
 2764   Plasma sheet
 2768   Plasmasphere
 2772   Plasma waves and instabilities
 2776   Polar cap phenomena
 2778   Ring current
 2780   Solar wind interactions with unmagnetized bodies
 2784   Solar wind/magnetosphere interactions
 2788   Storms and substorms
 2794   Instruments and techniques
 2799   General or miscellaneous
 
 3000   MARINE GEOLOGY AND GEOPHYSICS
 3005   Geomagnetism (1550)
 3010   Gravity
 3015   Heat flow (benthic) and hydrothermal processes
 3020   Littoral processes
 3022   Marine sediments--processes and transport
 3025   Marine seismics (0935)
 3030   Micropaleontology
 3035   Midocean ridge processes
 3040   Plate tectonics (8150, 8155, 8157, 8158)
 3045   Seafloor morphology and bottom photography
 3094   Instruments and techniques
 3099   General or miscellaneous
 
 3200   MATHEMATICAL GEOPHYSICS (New field)
 3210   Modeling
 3220   Nonlinear dynamics
 3230   Numerical solutions
 3240   Chaos
 3250   Fractals and multifractals
 3260   Inverse theory
 3299   General or miscellaneous
 
 3300   METEOROLOGY AND ATMOSPHERIC DYNAMICS
 3304   Atmospheric electricity
 3307   Boundary layer processes
 3309   Climatology (1620)
 3314   Convective processes
 3319   General circulation
 3322   Land/atmosphere interactions
 3324   Lightning
 3329   Mesoscale meteorology
 3332   Mesospheric dynamics
 3334   Middle atmosphere dynamics (0341, 0342)
 3337   Numerical modeling and data assimilation
 3339   Ocean/atmosphere interactions (0312, 4504)
 3344   Paleoclimatology
 3346   Planetary meteorology (5445, 5739)
 3349   Polar meteorology
 3354   Precipitation (1854)
 3359   Radiative processes
 3360   Remote sensing
 3362   Stratosphere/troposphere interactions
 3364   Synoptic-scale meteorology
 3367   Theoretical modeling
 3369   Thermospheric dynamics (0358)
 3374   Tropical meteorology
 3379   Turbulence
 3384   Waves and tides
 3394   Instruments and techniques
 3399   General or miscellaneous
 
 3600   MINERALOGY AND PETROLOGY (replaces 
        Mineralogy, Petrology, and Rock Chemistry)
 3620   Crystal chemistry
 3625   Descriptive mineralogy
 3630   Experimental mineralogy and petrology
 3640   Igneous petrology
 3655   Major element composition
 3660   Metamorphic petrology
 3662   Meteorites
 3665   Mineral occurrences and deposits
 3670   Minor and trace element composition
 3672   Planetary mineralogy and petrology (5410)
 3675   Sedimentary petrology
 3694   Instruments and techniques
 3699   General or miscellaneous
 
 3900   MINERAL PHYSICS
 3902   Creep and deformation
 3904   Defects
 3909   Elasticity and anelasticity
 3914   Electrical properties
 3919   Equations of state
 3924   High-pressure behavior
 3929   NMR, Mossbauer spectroscopy, and other magnetic techniques
 3934   Optical, infrared, and Raman spectroscopy
 3939   Physical thermodynamics
 3944   Shock wave experiments
 3947   Surfaces and interfaces
 3949   Thermal expansivity
 3954   X ray, neutron, and electron spectroscopy and diffraction
 3994   Instruments and techniques
 3999   General or miscellaneous
 
 4200   OCEANOGRAPHY: GENERAL
 4203   Analytical modeling
 4207   Arctic and Antarctic oceanography
 4211   Benthic boundary layers
 4215   Climate and interannual variability (3309)
 4219   Continental shelf processes
 4221   Dendrochronology
 4223   Descriptive and regional oceanography
 4227   Diurnal, seasonal, and annual cycles
 4231   Equatorial oceanography
 4235   Estuarine processes
 4239   Limnology
 4243   Marginal and semienclosed seas
 4247   Marine meteorology
 4251   Marine pollution
 4255   Numerical modeling
 4259   Ocean acoustics
 4263   Ocean prediction
 4267   Paleoceanography
 4271   Physical and chemical properties of seawater
 4275   Remote sensing and electromagnetic processes (0689)
 4279   Upwelling and convergences
 4283   Water masses
 4294   Instruments and techniques
 4299   General or miscellaneous
 
 4500   OCEANOGRAPHY: PHYSICAL
 4504   Air/sea interactions (0312)
 4506   Capillary waves
 4508   Coriolis effects
 4512   Currents
 4516   Eastern boundary currents
 4520   Eddies and mesoscale processes
 4522   El Ni?o
 4524   Fine structure and microstructure
 4528   Fronts and jets
 4532   General circulation
 4536   Hydrography
 4540   Ice mechanics and air/sea/ice exchange processes
 4544   Internal and inertial waves
 4546   Nearshore processes
 4548   Ocean fog and aerosols
 4552   Ocean optics
 4556   Sea level variations
 4558   Sediment transport
 4560   Surface waves and tides (1255)
 4564   Tsunamis and storm surges
 4568   Turbulence, diffusion, and mixing processes
 4572   Upper ocean processes
 4576   Western boundary currents
 4594   Instruments and techniques
 4599   General or miscellaneous
 
 4800   OCEANOGRAPHY: BIOLOGICAL AND CHEMICAL
 4801   Aerosols (0305)
 4802   Anoxic environments
 4803   Bacteria
 4804   Benthic processes/benthos
 4805   Biogeochemical cycles (1615)
 4806   Carbon cycling
 4807   Chemical speciation and complexation
 4808   Chemical tracers
 4809   Colloids
 4810   Corrosion
 4815   Ecosystems, structure and dynamics
 4817   Food chains
 4820   Gases
 4825   Geochemistry
 4830   Higher marine organisms
 4832   Hydrothermal systems
 4834   Hypoxic environments
 4835   Inorganic marine chemistry
 4840   Microbiology
 4842   Modeling
 4845   Nutrients and nutrient cycling
 4847   Optics
 4850   Organic marine chemistry
 4851   Oxidation/reduction reactions
 4852   Photochemistry
 4853   Photosynthesis
 4854   Physicochemical properties
 4855   Plankton
 4857   Pollution
 4860   Radioactivity and radioisotopes
 4863   Sedimentation
 4866   Sorptive scavenging
 4870   Stable isotopes
 4875   Trace elements
 4880   Trophodynamics
 4885   Weathering
 4894   Instruments and techniques
 4899   General or miscellaneous
 
 5100   PHYSICAL PROPERTIES OF ROCKS
 5102   Acoustic properties
 5104   Fracture and flow
 5109   Magnetic and electrical properties
 5112   Microstructure
 5114   Permeability and porosity
 5120   Plasticity, diffusion, and creep
 5134   Thermal properties
 5139   Transport properties
 5144   Wave attenuation
 5194   Instruments and techniques
 5199   General or miscellaneous
 
 5400   PLANETOLOGY: SOLID SURFACE PLANETS
 5405   Atmospheres--composition and chemistry
 5407   Atmospheres--evolution
 5409   Atmospheres--structure and dynamics
 5410   Composition
 5415   Erosion and weathering
 5416   Glaciation
 5417   Gravitational fields (1227)
 5418   Heat flow
 5420   Impact phenomena (includes cratering)
 5421   Interactions with particles and fields
 5430   Interiors (8147)
 5435   Ionospheres (2459)
 5440   Magnetic fields and magnetism
 5443   Magnetospheres (2756)
 5445   Meteorology (3346)
 5450   Orbital and rotational dynamics
 5455   Origin and evolution
 5460   Physical properties of materials
 5462   Polar regions
 5464   Remote sensing
 5465   Rings and dust
 5470   Surface materials and properties
 5475   Tectonics (8149)
 5480   Volcanism (8450)
 5494   Instruments and techniques
 5499   General or miscellaneous
 
 5700   PLANETOLOGY: FLUID PLANETS
 5704   Atmospheres--composition and chemistry
 5705   Atmospheres--evolution
 5707   Atmospheres--structure and dynamics
 5709   Composition
 5714   Gravitational fields (1227)
 5717   Impact phenomena
 5719   Interactions with particles and fields
 5724   Interiors (8147)
 5729   Ionospheres (2459)
 5734   Magnetic fields and magnetism
 5737   Magnetospheres (2756)
 5739   Meteorology (3346)
 5744   Orbital and rotational dynamics
 5749   Origin and evolution
 5754   Physical properties of materials
 5757   Remote sensing
 5759   Rings and dust
 5764   Surfaces
 5770   Tidal forces
 5780   Tori and exospheres
 5794   Instruments and techniques
 5799   General or miscellaneous
 
 6000   PLANETOLOGY:  COMETS AND SMALL BODIES
 6005   Atmospheres--composition and chemistry
 6006   Atmospheres--evolution
 6007   Atmospheres--structure and dynamics
 6008   Composition
 6015   Dust
 6019   Gravitational fields
 6020   Ice
 6022   Impact phenomena
 6025   Interactions with solar wind plasma and fields
 6026   Ionospheres--composition and chemistry
 6027   Ionospheres--evolution
 6028   Ionospheres--structure and dynamics
 6030   Magnetic fields and magnetism
 6035   Orbital and rotational dynamics
 6040   Origin and evolution
 6045   Physics and chemistry of materials
 6050   Plasma and MHD instabilities
 6060   Radiation and spectra
 6061   Remote sensing
 6062   Satellites
 6055   Surfaces and interiors
 6094   Instruments and techniques
 6099   General or miscellaneous
 
 6200   PLANETOLOGY:  SOLAR SYSTEM OBJECTS (New field)
 6205   Asteroids and meteoroids
 6207   Comparative planetology
 6210   Comets
 6213   Dust
 6215   Extraterrestrial materials
 6218   Jovian satellites
 6220   Jupiter
 6225   Mars
 6230   Martian satellites
 6235   Mercury
 6240   Meteorites and tektites
 6245   Meteors
 6250   Moon (1221)
 6255   Neptune
 6260   Neptunian satellites
 6265   Planetary rings
 6270   Pluto and satellites
 6275   Saturn
 6280   Saturnian satellites
 6285   Stellar planetary systems
 6290   Uranian satellites
 6293   Uranus
 6295   Venus
 6297   Instruments and techniques
 6299   General or miscellaneous
 
 6300   POLICY SCIENCES
 6304   Benefit-cost analysis
 6309   Decision making under uncertainty
 6314   Demand estimation
 6319   Institutions
 6324   Legislation and regulations
 6329   Project evaluation
 6334   Regional planning
 6339   System design
 6344   System operation and management
 6399   General or miscellaneous
 
 6600   PUBLIC ISSUES
 6605   Education
 6610   Funding
 6615   Legislation and regulation
 6620   Science policy
 6630   Workforce
 6699   General or miscellaneous
 
 6900   RADIO SCIENCE
 6904   Atmospheric propagation
 6909   Electromagnetic metrology
 6914   Electromagnetic noise and interference
 6919   Electro-optics
 6924   Interferometry
 6929   Ionospheric physics (2409)
 6934   Ionospheric propagation (2487)
 6939   Magnetospheric physics
 6944   Nonlinear phenomena
 6949   Radar astronomy
 6952   Radar atmospheric physics
 6954   Radio astronomy
 6959   Radio oceanography
 6964   Radio wave propagation
 6969   Remote sensing
 6974   Signal processing
 6979   Space and satellite communication
 6982   Tomography and imaging
 6984   Waves in plasma
 6994   Instruments and techniques
 6999   General or miscellaneous
 
 7200   SEISMOLOGY
 7203   Body wave propagation
 7205   Continental crust (1242)
 7207   Core and mantle
 7209   Earthquake dynamics and mechanics
 7212   Earthquake ground motions and engineering
 7215   Earthquake parameters
 7218   Lithosphere and upper mantle
 7219   Nuclear explosion seismology
 7220   Oceanic crust 
 7221   Paleoseismology
 7223   Seismic hazard assessment and prediction
 7230   Seismicity and seismotectonics
 7255   Surface waves and free oscillations
 7260   Theory and modeling
 7280   Volcano seismology (8419)
 7294   Instruments and techniques
 7299   General or miscellaneous
 
 7500   SOLAR PHYSICS, ASTROPHYSICS, AND ASTRONOMY
 7504   Celestial mechanics
 7507   Chromosphere
 7509   Corona
 7511   Coronal holes
 7513   Coronal mass ejections
 7514   Energetic particles (2114)
 7519   Flares
 7522   Helioseismology
 7524   Magnetic fields
 7529   Photosphere
 7531   Prominence eruptions
 7534   Radio emissions
 7536   Solar activity cycle (2162)
 7537   Solar and stellar variability
 7538   Solar irradiance
 7539   Stellar astronomy
 7544   Stellar interiors and dynamo theory
 7546   Transition region
 7549   Ultraviolet emissions
 7554   X rays, gamma rays, and neutrinos
 7594   Instruments and techniques
 7599   General or miscellaneous
 
 7800   SPACE PLASMA PHYSICS
 7803   Active perturbation experiments
 7807   Charged particle motion and acceleration
 7811   Discontinuities
 7815   Electrostatic structures
 7819   Experimental and mathematical techniques
 7823   Ionization processes
 7827   Kinetic and MHD theory
 7831   Laboratory studies
 7835   Magnetic reconnection
 7837   Neutral particles
 7839   Nonlinear phenomena
 7843   Numerical simulation studies
 7847   Radiation processes
 7851   Shock waves
 7853   Spacecraft/atmosphere interactions
 7855   Spacecraft sheaths, wakes, charging
 7859   Transport processes
 7863   Turbulence
 7867   Wave/particle interactions
 7868   Wave/wave interactions
 7871   Waves and instabilities
 7894   Instruments and techniques
 7899   General or miscellaneous
 
 8000   STRUCTURAL GEOLOGY (New field, replaces single entry 8165)
 8005   Folds and folding
 8010   Fractures and faults
 8015   Local crustal structure
 8020   Mechanics
 8025   Mesoscopic fabrics
 8030   Microstructures
 8035   Pluton emplacement
 8040   Remote sensing
 8045   Role of fluids
 8094   Instruments and techniques
 8099   General or miscellaneous
 
 8100   TECTONOPHYSICS
 8102   Continental contractional orogenic belts
 8105   Continental margins and sedimentary basins
 8107   Continental neotectonics
 8109   Continental tectonics--extensional (0905)
 8110   Continental tectonics--general (0905)
 8115   Core processes (1507)
 8120   Dynamics of lithosphere and mantle--general
 8121   Dynamics, convection currents and mantle plumes
 8122   Dynamics, gravity and tectonics
 8123   Dynamics, seismotectonics
 8124   Earth's interior--composition and state (old 8105)
 
 8125   Evolution of the Earth
 8130   Heat generation and transport
 8135   Hydrothermal systems (8424)
 8145   Physics of magma and magma bodies
 8147   Planetary interiors (5430, 5724)
 8149   Planetary tectonics (5475)
 8150   Plate boundary--general (3040)
 8155   Plate motions--general
 8157   Plate motions--past (3040)
 8158   Plate motions--present and recent (3040)
 8159   Rheology--crust and lithosphere
 8160   Rheology--general
 8162   Rheology--mantle
 8164   Stresses--crust and lithosphere
 8166   Stresses--deep-seated
 8168   Stresses--general
 8180   Tomography
 8194   Instruments and techniques
 8199   General or miscellaneous
 
 8400   VOLCANOLOGY
 8404   Ash deposits
 8409   Atmospheric effects (0370)
 8414   Eruption mechanisms
 8419   Eruption monitoring (7280)
 8424   Hydrothermal systems (8135)
 8429   Lava rheology and morphology
 8434   Magma migration
 8439   Physics and chemistry of magma bodies
 8450   Planetary volcanism (5480)
 8494   Instruments and techniques
 8499   General or miscellaneous
 
 9300   INFORMATION RELATED TO GEOGRAPHIC REGION
 9305   Africa
 9310   Antarctica
 9315   Arctic region
 9320   Asia
 9325   Atlantic Ocean
 9330   Australia
 9335   Europe
 9340   Indian Ocean
 9345   Large bodies of water (e.g., lakes and inland seas)
 9350   North America
 9355   Pacific Ocean
 9360   South America
 9399   General or miscellaneous
 
 9600   INFORMATION RELATED TO GEOLOGIC TIME
 9604   Cenozoic
 9609   Mesozoic
 9614   Paleozoic
 9619   Precambrian
 9699   General or miscellaneous
 
 9800   GENERAL OR MISCELLANEOUS
 9805   Instruments useful in three or more fields
 9810   New fields (not classifiable under other headings)
 9815   Notices and announcements
 9820   Techniques applicable in three or more fields
 
 9900 CORRECTIONS