This section contains 46 articles.

1. Earth science (Level 3)
2. Biogeochemical cycle
   1. Calcium cycle
   2. Carbon cycle
      1. Carbon sequestration
   3. Nitrogen cycle
   4. Oxygen cycle
   5. Phosphorus cycle
3. Natural environment
   1. Environmental issues
      1. Environmental conflict
         1. Environmental justice
         2. Tragedy of the commons
      2. Environmental degradation
      3. Human–wildlife conflict
   2. Environmental protection
   3. Environmental studies
      1. Environmental policy
      2. Environmental science
   4. Human impact on the environment
      1. Land use
   5. Wilderness
4. Earth's rotation
   1. Foucault pendulum
5. Figure of the Earth
   1. Earth ellipsoid
   2. Equatorial bulge
   3. Flat Earth
   4. Spherical Earth
   5. Schiehallion experiment
6. Gaia hypothesis
7. History of Earth (Level 3)
   1. Early Earth
   2. Extinction event (Level 4)
   3. Ice age (Level 4)
   4. Milankovitch cycles
8. Natural disaster (Level 4)
   1. Disaster response
   2. Wildfire (Level 4)
9. Natural resource (Level 4)
   1. Conflict minerals law
   2. Environmental resource management
   3. Overexploitation
      1. Overfishing
10. Planetary boundaries
11. Thermocline

This section contains 49 articles.

This section contains 14 articles.

1. Drylands
   1. Desert (Level 3)
      1. Desertification
      2. Oasis (Level 4)
   2. Deserts and xeric shrublands
   3. Drought (Level 4)
2. Shrubland (Level 4)
   1. Chaparral
   2. Fynbos
   3. Heath
   4. Mediterranean forests, woodlands, and scrub
   5. Moorland
3. Tundra (Level 4)
   1. Alpine tundra

This section contains 17 articles.

1. Forest (Level 3)
2. Rainforest (Level 4)
   1. Tropical rainforest (Level 4)
   2. Tropical and subtropical moist broadleaf forests
   3. Temperate rainforest
3. Taiga (Level 4)
4. Temperate forest
   1. Temperate broadleaf and mixed forests (Level 4)
   2. Temperate coniferous forest
   3. Temperate deciduous forest
5. Tropical forest
   1. Jungle (Level 4)
   2. Seasonal tropical forest
      1. Tropical and subtropical dry broadleaf forests
   3. Tropical and subtropical coniferous forests
6. Woodland
   1. Grove (nature)

This section contains 8 articles.

1. Grassland (Level 3)
2. Meadow (Level 4)
3. Montane grasslands and shrublands
4. Prairie (Level 4)
5. Savanna (Level 4)
6. Steppe (Level 4)
7. Temperate grasslands, savannas, and shrublands
8. Tropical and subtropical grasslands, savannas, and shrublands

This section contains 10 articles.

1. Wetland (Level 4)
2. Bog (Level 4)
3. Fen
4. Flooded grasslands and savannas
5. Mangrove (Level 4)
6. Marsh (Level 4)
7. Peatland
8. Riparian zone
9. Salt marsh
10. Swamp (Level 4)

This section contains 66 articles.

This section contains 5 articles.

1. Climatology (Level 4)
2. Climate system
3. El Niño–Southern Oscillation (Level 4)
4. Köppen climate classification (Level 4)
5. Microclimate

This section contains 17 articles.

1. Climate (Level 2)
2. Alpine climate
   1. Montane ecosystem
3. Continental climate
4. Desert climate
5. Humid subtropical climate
6. Polar climate
   1. Climate of Antarctica
   2. Climate of the Arctic
7. Semi-arid climate
8. Subarctic climate
9. Temperate climate (Level 4)
   1. Mediterranean climate
10. Tropical climate (Level 4)
    1. Tropical monsoon climate
    2. Tropical rainforest climate
    3. Tropical savanna climate

This section contains 44 articles.

1. Climate change (Level 3)
2. Climate change in Africa
3. Climate change in Antarctica
4. Climate change denial
5. Climate change in Europe
6. Climate change feedbacks
   1. Arctic methane emissions
   2. Climate sensitivity
   3. Ice–albedo feedback
   4. Tipping points in the climate system
7. Climate change in the Middle East and North Africa
8. Climate change mitigation
9. Climate change vulnerability
10. Climate model
11. Climate variability and change (Level 4)
12. Deforestation and climate change
    1. Deforestation of the Amazon rainforest
13. Earth's energy budget
    1. Outgoing longwave radiation
    2. Radiative forcing
    3. Solar irradiance
14. Economic analysis of climate change
15. Effects of climate change
    1. Arctic sea ice decline
    2. Effects of climate change on agriculture
    3. Effects of climate change on human health
    4. Effects of climate change on oceans
       1. Ocean acidification
    5. Effects of climate change on small island countries
    6. Extreme weather
    7. Global dimming
16. Greenhouse effect (Level 4)
17. Greenhouse gas
18. Greenhouse gas emissions
    1. Carbon budget
       1. Climate change in Australia
       2. Climate change in Brazil
       3. Climate change in Canada
       4. Climate change in India
       5. Climate change in Indonesia
       6. Climate change in Japan
    2. Methane emissions
19. Politics of climate change
20. Solar activity and climate

This section contains 13 articles.

1. Season (Level 3)
2. Spring (season) (Level 4)
3. Summer (Level 4)
   1. Heat wave
4. Autumn (Level 4)
5. Winter (Level 4)
   1. Cold wave
6. Wet season
   1. East Asian monsoon
   2. Monsoon of South Asia
7. Dry season
   1. Harmattan
8. Atlantic hurricane season

This section contains 27 articles.

This section contains 13 articles.

1. Atmosphere of Earth (Level 3)
   1. Troposphere
   2. Stratosphere
      1. Ozone layer
   3. Mesosphere
   4. Thermosphere
   5. Exosphere
      1. Atmospheric escape
      2. Kármán line
2. Air mass (Level 4)
3. Atmospheric pressure (Level 4)
4. Atmospheric science (Level 4)
5. Ozone depletion (Level 4)

This section contains 14 articles.

1. Aurora (Level 4)
2. Glory (optical phenomenon)
3. Halo (optical phenomenon)
4. Haze
   1. Smog
5. Heiligenschein
6. Light pillar
7. Mirage (Level 4)
   1. Fata Morgana (mirage)
8. Rainbow (Level 4)
9. Sky (Level 4)
   1. Diffuse sky radiation
10. Sun dog
11. Sunlight

This section contains 106 articles.

This section contains 11 articles.

1. Meteorology (Level 4)
2. Weather (Level 3)
3. Weather front (Level 4)
4. Weather forecasting (Level 4)
   1. Marine weather forecasting
   2. Weather station
   3. Surface weather observation
   4. Surface weather analysis
5. Humidity (Level 4)
6. Low-pressure area (Level 4)
7. Indian summer

This section contains 23 articles.

1. Cloud (Level 3)
2. Cirrus cloud (Level 4)
3. Cumulonimbus cloud (Level 4)
4. Cumulus cloud (Level 4)
   1. Cumulus congestus cloud
   2. Cumulus humilis cloud
   3. Cumulus mediocris cloud
5. Fog (Level 4)
6. Mist
7. Diamond dust
8. Funnel cloud
9. Cirrostratus cloud
   1. Cirrostratus nebulosus
10. Nimbostratus cloud
11. Fractus cloud
12. Stratus cloud
13. Altostratus cloud
    1. Altostratus undulatus cloud
14. Stratocumulus cloud
15. Altocumulus cloud
16. Cirrocumulus cloud
17. Noctilucent cloud
18. Polar stratospheric cloud

This section contains 14 articles.

1. Precipitation (Level 4)
2. Rain (Level 3)
   1. Acid rain (Level 4)
   2. Freezing rain
3. Snow (Level 3)
4. Hail (Level 4)
5. Dew (Level 4)
6. Frost (Level 4)
7. Ice pellets
8. Rain and snow mixed
9. Graupel
10. Drizzle
11. Cloudburst
12. Rain shadow

This section contains 7 articles.

1. Atmospheric circulation (Level 4)
2. High-pressure area (Level 4)
3. Cyclone (Level 4)
4. Extratropical cyclone (Level 4)
5. Hadley cell (Level 4)
6. Polar vortex (Level 4)
7. Walker circulation (Level 4)

This section contains 38 articles.

1. Storm (Level 4)
2. Winter storm
   1. Blizzard (Level 4)
   2. Ice storm
   3. Snow squall
   4. Whiteout (weather)
3. Whirlwind
   1. Tornado (Level 3)
      1. Landspout
      2. Waterspout
   2. Gustnado
   3. Fire whirl
   4. Dust devil
   5. Steam devil
4. Tropical cyclone (Level 3)
   1. Atlantic hurricane
   2. Eye (cyclone)
   3. Saffir–Simpson scale
   4. Storm surge
   5. Tropical cyclogenesis
   6. Tropical cyclone forecasting
      1. Dvorak technique
      2. Tropical cyclone rainfall forecasting
      3. Tropical cyclone track forecasting
   7. Tropical cyclone preparedness
   8. Typhoon
5. Dust storm (Level 4)
   1. Dust
6. Atmospheric electricity
   1. Lightning (Level 4)
      1. Lightning strike
      2. Ball lightning
      3. Sprite (lightning)
      4. Thunder
   2. Thunderstorm (Level 4)
      1. Supercell
7. Geomagnetic storm
8. St. Elmo's fire

This section contains 13 articles.

1. Wind (Level 3)
2. Foehn wind
3. Intertropical Convergence Zone
4. Jet stream (Level 4)
5. Katabatic wind
6. Mistral (wind)
7. Monsoon (Level 4)
8. Prevailing winds
9. Sea breeze
10. Trade winds (Level 4)
11. Vertical draft
12. Westerlies
13. Wind shear

This section contains 13 articles.

1. Geology (Level 2)
2. Core sample
   1. Dendrochronology
   2. Ice core
3. Geologic record
4. Mohs scale
5. Internal structure of Earth (Level 3)
   1. Earth's crust
   2. Earth's inner core (Level 4)
   3. Earth's outer core (Level 4)
   4. Mantle (geology) (Level 4)
   5. Mohorovičić discontinuity
   6. Geological hazard

This section contains 16 articles.

1. Geochemistry
2. Isotope geochemistry
   1. Primordial nuclide
   2. δ¹³C
   3. δ¹⁸O
3. Geochemical cycle
4. Goldschmidt classification
5. Igneous differentiation
   1. Partial melting
6. Natural hydrogen
7. Trace element
8. Biogeochemistry
   1. Organic geochemistry
   2. Remineralisation
9. Radium and radon in the environment
10. Recrystallization (geology)

This section contains 56 articles.

1. Geophysics (Level 4)
2. Earth's internal heat budget
3. Earth's magnetic field (Level 4)
   1. Geomagnetic pole
   2. Geomagnetic reversal
   3. Ionosphere
   4. Magnetic anomaly
   5. North magnetic pole
   6. South magnetic pole
   7. Van Allen radiation belt
4. Forensic geophysics
5. Geodesy (Level 4)
   1. Physical geodesy
6. Geodynamics
   1. Byerlee's law
7. Geomathematics
8. Geophysical fluid dynamics
9. Geothermal gradient
10. Gravimetry
    1. Gravity of Earth
11. Isostasy
12. Mantle convection
    1. Mantle plume
13. Near-surface geophysics
14. Soil liquefaction
15. Theory of tides

This section contains 30 articles.

1. Seismology (Level 4)
2. Seismic wave
   1. P wave
   2. S wave
   3. Love wave
3. Seismic intensity scales
   1. Modified Mercalli intensity scale
4. Seismic magnitude scales
   1. Richter scale
   2. Moment magnitude scale
5. Seismic refraction
6. Seismic tomography
7. Seismic zone
8. Shadow zone
9. Elastic-rebound theory
10. Earthquake (Level 3)
    1. Mainshock
    2. Foreshock
    3. Aftershock
    4. Megathrust earthquake
    5. Epicenter
    6. Focal mechanism
    7. Earthquake preparedness
    8. Earthquake prediction
    9. Earthquake forecasting
    10. Earthquake early warning system
    11. Slow earthquake
    12. Interplate earthquake
    13. Intraplate earthquake
    14. Deep-focus earthquake

This section contains 95 articles.

This section contains 3 articles.

1. Geological history of Earth (Level 4)
2. Age of Earth
3. Historical geology

This section contains 13 articles.

1. Geochronology (Level 4)
2. Absolute dating
   1. Radiometric dating
   2. Closure temperature
   3. K–Ar dating
   4. Argon–argon dating
   5. Rubidium–strontium dating
   6. Uranium–lead dating
3. Relative dating
4. Detrital zircon geochronology
5. Monazite geochronology
6. Paleomagnetism
7. Thermochronology

This section contains 4 articles.

1. Paleoclimatology
2. Geological history of oxygen
3. Paleotempestology
4. Paleothermometer

This section contains 21 articles.

1. Late Heavy Bombardment
2. Great Oxidation Event (Level 4)
3. Snowball Earth
   1. Huronian glaciation
   2. Sturtian glaciation
   3. Marinoan glaciation
4. Cambrian explosion (Level 4)
5. Late Ordovician mass extinction (Level 4)
6. Hirnantian glaciation
7. Late Devonian extinction (Level 4)
8. Late Paleozoic icehouse
9. Permian–Triassic extinction event (Level 4)
10. Triassic–Jurassic extinction event (Level 4)
11. Cretaceous–Paleogene extinction event (Level 4)
    1. Alvarez hypothesis
12. Paleocene–Eocene Thermal Maximum
13. Quaternary glaciation
14. Last Glacial Period
    1. Last Glacial Maximum
15. Late Pleistocene extinctions
    1. Holocene extinction

This section contains 18 articles.

1. Paleocontinent
   1. Baltica
   2. Laurentia
2. Supercontinent
   1. Gondwana
   2. Kenorland
   3. Laurasia
   4. Pangaea (Level 4)
   5. Pannotia
   6. Rodinia
   7. Ur (continent)
   8. Vaalbara
3. Iapetus Ocean
4. Paleo-Tethys Ocean
5. Panthalassa
6. Rheic Ocean
7. Tethys Ocean
8. Western Interior Seaway

This section contains 36 articles.

1. Geologic time scale (Level 4)
2. Precambrian (Level 4)
   1. Hadean
   2. Archean
      1. Eoarchean
      2. Paleoarchean
      3. Mesoarchean
   3. Proterozoic
      1. Paleoproterozoic
      2. Mesoproterozoic
      3. Neoproterozoic
         1. Ediacaran
3. Phanerozoic (Level 4)
   1. Paleozoic (Level 4)
      1. Cambrian (Level 4)
      2. Ordovician
      3. Silurian
      4. Devonian
      5. Carboniferous
      6. Permian (Level 4)
   2. Mesozoic (Level 4)
      1. Triassic (Level 4)
      2. Jurassic (Level 4)
      3. Cretaceous (Level 4)
   3. Cenozoic (Level 4)
      1. Paleogene (Level 4)
         1. Paleocene
         2. Eocene
         3. Oligocene
      2. Neogene (Level 4)
         1. Miocene
         2. Pliocene
      3. Quaternary (Level 4)
         1. Pleistocene
         2. Holocene (Level 4)
         3. Anthropocene

This section contains 466 articles.

This section contains 1 article.

1. Aggregate (geology)

This section contains 21 articles.

1. Algoman orogeny
2. Andean orogeny
3. Belt Supergroup
4. Central Asian Orogenic Belt
5. Columbia River Basalt Group
6. Cretaceous–Paleogene boundary
7. Deccan Traps
8. Diapir
9. Dike (geology)
10. Geology of the Appalachians
11. Geology of the Himalayas
12. Hawaii hotspot
13. Hydrothermal vent
14. Laramide orogeny
15. Siberian Traps
16. Sill (geology)
17. Slave Craton
    1. Acasta Gneiss
18. Slickenside
19. Terra Australis Orogen
20. Yellowstone hotspot

This section contains 173 articles.

1. Mineral (Level 3)
2. Mineralogy (Level 4)
3. Arsenate mineral
   1. Erythrite
4. Arsenide mineral
   1. Loellingite
   2. Skutterudite
   3. Sperrylite
5. Borate mineral
   1. Boracite
   2. Kernite
   3. Colemanite
   4. Ulexite
   5. Painite
6. Carbonate mineral
   1. Aragonite
   2. Azurite
   3. Bastnäsite
   4. Calcite
      1. Iceland spar
   5. Dolomite (mineral)
   6. Magnesite
   7. Malachite
   8. Rhodochrosite
   9. Siderite
   10. Smithsonite
       1. Calamine (mineral)
7. Crocoite
8. Earth pigment
   1. Chalk
   2. Ochre
      1. Sienna
      2. Umber
9. Gemstone
10. Halide mineral
    1. Cryolite
    2. Fluorite
       1. Antozonite
    3. Halite
    4. Sylvite
11. Mineral physics
12. Native element mineral
    1. Native metal
       1. Meteoric iron
       2. Native copper
       3. Telluric iron
13. Oxide mineral
    1. Anatase
    2. Brookite
    3. Brucite
    4. Cassiterite
    5. Chrysoberyl
    6. Corundum
       1. Sapphire (Level 4)
       2. Ruby (Level 4)
    7. Cuprite
    8. Hematite
    9. Ilmenite
    10. Limonite
    11. Magnetite
    12. Perovskite
    13. Portlandite
    14. Psilomelane
    15. Pyrolusite
    16. Rutile
    17. Spinel group
        1. Chromite
        2. Spinel
    18. Tantalite
        1. Coltan
    19. Thorianite
    20. Uraninite
14. Phosphate mineral
    1. Apatite
    2. Fluorapatite
    3. Monazite
    4. Phosphorite
    5. Turquoise
15. Scheelite
16. Silicate mineral
    1. Aluminosilicate
       1. Pollucite
       2. Stilbite
       3. Zeolite
    2. Asbestos (Level 4)
    3. Feldspathoid
       1. Nosean
       2. Petalite
       3. Sodalite
       4. Hauyne
       5. Lazurite
       6. Tugtupite
    4. Olivine
       1. Fayalite
       2. Forsterite
       3. Peridot
    5. Garnet
    6. Hemimorphite
    7. Zircon
    8. Andalusite
    9. Sillimanite
    10. Kyanite
    11. Staurolite
    12. Topaz
    13. Opal
    14. Titanite
    15. Tourmaline
    16. Epidote
        1. Allanite
        2. Tanzanite
    17. Beryl
        1. Aquamarine (gem)
        2. Emerald (Level 4)
    18. Pyroxene (Level 4)
        1. Augite
        2. Diopside
        3. Enstatite
        4. Hedenbergite
        5. Pigeonite
        6. Spodumene
        7. Wollastonite
    19. Amphibole
        1. Hornblende
        2. Cummingtonite
        3. Jade (Level 4)
    20. Mica (Level 4)
        1. Biotite
        2. Lepidolite
        3. Muscovite
        4. Clay mineral
           1. Hectorite
           2. Kaolinite (Level 4)
           3. Serpentine subgroup
           4. Serpentinization
           5. Serpentinite
           6. Talc (Level 4)
    21. Chlorite group
    22. Quartz (Level 4)
        1. Amethyst
        2. Chalcedony
           1. Carnelian
        3. Flint
           1. Onyx
    23. Feldspar (Level 4)
        1. Plagioclase
           1. Labradorite
        2. Orthoclase
        3. Microcline
        4. Anorthite
        5. Albite
    24. Vermiculite
17. Sulfate mineral
    1. Alunite
    2. Anhydrite
    3. Baryte
    4. Gypsum (Level 4)
    5. Jarosite
18. Sulfide mineral
    1. Arsenopyrite
    2. Bornite
    3. Chalcopyrite
    4. Cinnabar
    5. Cobaltite
    6. Galena
    7. Greenockite
    8. Pentlandite
    9. Orpiment
    10. Pyrite
    11. Realgar
    12. Sphalerite
    13. Stibnite
    14. Troilite
19. Wolframite

This section contains 74 articles.

1. Petrology (Level 4)
2. Rock (geology) (Level 3)
   1. Bedrock
   2. Ore (Level 4)
3. Bowen's reaction series
4. Igneous rock (Level 4)
   1. Volcanic rock
   2. Extrusive rock
      1. Andesite
         1. Boninite
      2. Basalt (Level 4)
      3. Dacite
      4. Komatiite
      5. Rhyolite
   3. Intrusive rock
      1. Granite (Level 4)
         1. Greisen
      2. Granodiorite
      3. Diorite
      4. Gabbro
      5. Pegmatite
      6. Peridotite
         1. Kimberlite
   4. Tuff (Level 4)
   5. Magma (Level 4)
   6. Igneous intrusion
   7. Batholith
   8. Porphyry (geology)
      1. Porphyry copper deposit
   9. Volcanic glass
      1. Obsidian
      2. Pumice
5. Metamorphic rock (Level 4)
   1. Schist (Level 4)
      1. Greenschist
      2. Blueschist
   2. Marble (Level 4)
   3. Gneiss (Level 4)
   4. Slate (Level 4)
   5. Amphibolite
   6. Granulite
   7. Hornfels
   8. Migmatite
   9. Phyllite
   10. Quartzite
   11. Tectonite
       1. Cataclasite
       2. Mylonite
6. Sedimentary rock (Level 4)
   1. Carbonate rock
      1. Limestone (Level 4)
      2. Dolomite (rock)
      3. Oolite
   2. Clastic rock
      1. Shale
         1. Oil shale (Level 4)
      2. Mudrock
      3. Siltstone
      4. Sandstone (Level 4)
         1. Greywacke
      5. Conglomerate (geology) (Level 4)
      6. Breccia (Level 4)
   3. Bauxite (Level 4)
   4. Concretion
      1. Manganese nodule
   5. Evaporite
      1. Carnallite
      2. Kainite
   6. Banded iron formation
      1. Ironstone
   7. Nodule (geology)
   8. Turbidite
7. Meteorite (Level 4)
8. Porosity

This section contains 41 articles.

1. Sediment (Level 4)
2. Grain size
   1. Boulder
   2. Clay (Level 4)
   3. Cobble (geology)
   4. Gravel (Level 4)
   5. Loam
   6. Mud
   7. Pebble
   8. Sand (Level 4)
   9. Silt
3. Pelagic sediment
   1. Siliceous ooze
4. Till
5. Alluvium
6. Deposition (geology)
7. Diagenesis
8. Sedimentary basin (Level 4)
9. Sediment transport
   1. Sediment gravity flow
   2. Bed load
   3. Suspended load
   4. Dissolved load
10. Aggradation
11. Degradation (geology)
12. Bioturbation
13. Cementation (geology)
14. Sedimentary structures
    1. Cross-bedding
    2. Hummocky cross-stratification
    3. Bedform
       1. Ripple marks
    4. Soft-sediment deformation structures
    5. Mudcrack
15. Graded bedding
16. Lamination (geology)
17. Bed (geology)
18. Roundness (geology)
19. Regolith
20. Paleosol
21. Loess

This section contains 26 articles.

1. Soil science (Level 4)
2. Detritus
3. Edaphology
4. Humus
5. Soil (Level 3)
   1. Peat (Level 4)
   2. Podzol
   3. Topsoil
6. Soil chemistry
   1. Soil acidification
   2. Soil pH
7. Soil classification
   1. Soil texture
   2. Soil type
8. Soil erosion
9. Soil fertility (Level 4)
10. Soil formation (Level 4)
11. Soil health
12. Soil horizon
13. Soil morphology
14. Soil physics
15. Pedology
    1. Leaching (pedology)
16. Pedosphere (Level 4)
17. Plant litter
18. Tilth

This section contains 29 articles.

1. Stratigraphy (Level 4)
   1. Lithostratigraphy
   2. Biostratigraphy
   3. Chronostratigraphy
   4. Magnetostratigraphy
   5. Sequence stratigraphy
2. Stratigraphic unit
   1. Group (stratigraphy)
   2. Geological formation
3. Greenstone belt
4. Stratum
5. Marine regression
6. Marine transgression
7. Basement (geology)
8. Contact (geology)
   1. Unconformity
9. Law of superposition
10. Facies
11. Stratigraphic section
12. System (stratigraphy)
    1. Series (stratigraphy)
    2. Stage (stratigraphy)
13. Biozone
14. List of index fossils
15. Sequence (geology)
16. Parasequence
17. Type locality (geology)
18. Cratonic sequence
19. Past sea level

This section contains 22 articles.

1. Structural geology
2. Boudinage
3. Ductility (Earth science)
   1. Brittle–ductile transition zone
4. Fabric (geology)
   1. Foliation (geology)
      1. Crenulation
   2. Lineation (geology)
5. Fold (geology) (Level 4)
   1. Anticline
   2. Syncline
6. Fracture (geology)
   1. Joint (geology)
   2. Fault (geology) (Level 4)
      1. Thrust fault (Level 4)
      2. Detachment fault
      3. Shear (geology)
   3. Cleavage (geology)
   4. Vein (geology)
7. Shear zone
8. Strike and dip
9. Structural basin

This section contains 58 articles.

1. Plate tectonics (Level 3)
2. Continental drift
3. Continent (Level 3)
   1. Continental fragment
   2. Craton
4. Continental shelf (Level 4)
5. Continental margin
6. Continental rise
7. Abyssal plain (Level 4)
8. Divergent boundary
   1. Rift
   2. Mid-ocean ridge (Level 4)
   3. Pull-apart basin
9. Transform fault
10. Convergent boundary
    1. Subduction
       1. Oceanic trench (Level 4)
       2. Accretionary wedge
       3. Slab (geology)
       4. Slab pull
    2. Tectonic uplift
    3. Orogeny
       1. Forearc
       2. Back-arc basin
       3. Foreland basin
11. Passive margin
12. Décollement
13. Lithosphere (Level 4)
    1. Crust (geology) (Level 4)
       1. Continental crust
       2. Oceanic crust
14. Upper mantle
15. Lower mantle
16. Asthenosphere
17. Shield (geology)
18. Triple junction
19. Geologic province
20. Transition zone (Earth)
21. Core–mantle boundary

This section contains 19 articles.

1. African plate
2. Arabian plate
3. Amurian microplate
4. Antarctic plate
5. Caribbean plate
6. Cocos plate
7. Eurasian plate
8. Indo-Australian plate
9. Nazca plate
10. North American plate
11. Okhotsk microplate
12. Pacific plate
13. Philippine Sea plate
14. Scotia plate
15. Somali plate
16. South American plate
17. Sunda plate
18. Farallon plate
    1. Juan de Fuca plate

This section contains 21 articles.

1. Volcanology
2. Volcanism
3. Volcanic arc
4. Volcano (Level 3)
   1. Supervolcano
   2. Cinder cone
   3. Shield volcano
   4. Stratovolcano
   5. Complex volcano
5. Geyser (Level 4)
6. Hotspot (geology) (Level 4)
7. Lava (Level 4)
8. Lahar
9. Magma chamber
10. Volatile (astrogeology)
11. Pyroclastic flow
12. Hot spring
13. Lava dome
14. Submarine volcano
15. Volcanic crater
16. Volcanic plug

This section contains 10 articles.

1. Geomorphology (Level 4)
2. Erosion (Level 3)
   1. Abrasion (geology)
   2. Mass wasting
      1. Avalanche (Level 4)
      2. Landslide (Level 4)
      3. Mudflow
      4. Rockslide
3. Weathering (Level 4)
4. Subsidence

This section contains 105 articles.

This section contains 14 articles.

1. Landform (Level 4)
2. Land (Level 2)
3. Highland
4. Upland and lowland
5. Hill (Level 4)
6. Valley (Level 4)
   1. Rift valley
   2. Ravine
7. Plateau (Level 4)
8. Plain (Level 4)
9. Depression (geology)
   1. Impact crater (Level 4)
   2. Isostatic depression
10. Escarpment

This section contains 2 articles.

1. Aeolian processes (Level 4)
2. Dune (Level 4)

This section contains 3 articles.

1. Artificial island (Level 4)
2. Land reclamation (Level 4)
3. Polder (Level 4)

This section contains 10 articles.

1. Cave (Level 4)
   1. Speleology
2. Karst (Level 4)
3. Speleothem
   1. Stalactite
   2. Stalagmite
4. Solutional cave
5. Lava tube
6. Sinkhole
   1. Cenote

This section contains 14 articles.

1. River morphology
2. Alluvial fan (Level 4)
3. Canyon (Level 4)
4. Cut bank
5. Floodplain (Level 4)
6. Gully
7. Meander (Level 4)
8. Rapids (Level 4)
9. Waterfall (Level 4)
10. Bar (river morphology)
    1. Point bar
11. Promontory
12. Stream bed
13. Wadi

This section contains 7 articles.

1. Glacial landform (Level 4)
2. Cirque
3. Esker
4. Fjord (Level 4)
5. Moraine (Level 4)
6. Post-glacial rebound
7. U-shaped valley

This section contains 9 articles.

1. Mountain (Level 3)
   1. Mountain formation
   2. Mountain range (Level 4)
2. Fault block
3. Fold mountains
4. Mountain pass
5. Ridge
6. Summit
7. Scree

This section contains 32 articles.

1. Oceanic basin
2. Archipelago (Level 4)
3. Bay (Level 4)
4. Beach (Level 4)
   1. Shingle beach
5. Coast (Level 4)
   1. Cliffed coast
   2. Coastal geography
   3. Flat coast
6. Headland
   1. Cape (geography)
7. Lagoon (Level 4)
8. Peninsula (Level 4)
9. Island (Level 3)
   1. Tidal island
   2. Barrier island
   3. Coral island
      1. Atoll (Level 4)
   4. Volcanic island
   5. Islet
   6. Lake island
   7. River island
   8. Uninhabited island
10. Reef
11. Seamount (Level 4)
    1. Guyot
12. Mudflat
    1. Bay mud
13. Isthmus
14. Sea cave
15. Shoal
16. Stack (geology)

This section contains 7 articles.

1. Badlands
2. Butte
3. Cliff (Level 4)
4. Hummock
5. Mesa (Level 4)
6. Terrace (geology)
7. Tor (rock formation)

This section contains 7 articles.

1. Caldera
2. Flood basalt
3. Fumarole
4. Large igneous province
5. Lava field
6. Maar
7. Volcanic cone

This section contains 16 articles.

1. Aquatic ecosystem
   1. Deep-sea community
   2. Freshwater ecosystem
   3. Neuston
2. Cryosphere (Level 4)
3. Eutrophication
4. Flood (Level 3)
   1. Flash flood
5. Hydrosphere (Level 4)
6. Salinity
   1. Fresh water
   2. Brackish water
   3. Saline water
   4. Brine
7. Water quality
8. Whirlpool

This section contains 49 articles.

1. Oceanography (Level 4)
2. Marine chemistry
3. Marine ecosystem
   1. Marine coastal ecosystem
   2. Ocean surface ecosystem
      1. Sea surface microlayer
4. Marine habitat
   1. Coral reef (Level 4)
   2. Kelp forest
   3. Littoral zone
   4. Mangrove forest
   5. Neritic zone
   6. Seagrass meadow
   7. Benthic zone
   8. Marine sediment
5. Marine life
6. Ocean (Level 4)
7. Ocean dynamics
   1. Ekman transport
      1. Upwelling
   2. Ocean current (Level 4)
      1. Rip current
   3. Ocean surface topography
   4. Thermohaline circulation (Level 4)
8. Ocean temperature
   1. Sea surface temperature
9. Oceanic zone
   1. Pelagic zone
      1. Photic zone
      2. Aphotic zone
         1. Mesopelagic zone
         2. Bathypelagic zone
         3. Abyssal zone
         4. Hadal zone
10. Sea (Level 2)
11. Seabed (Level 4)
12. Sea level (Level 4)
    1. Sea level rise
13. Seawater
14. Strait
15. Tide (Level 4)
    1. Intertidal zone
    2. Tide pool
    3. Tidal range
16. Tsunami (Level 4)
    1. Megatsunami
17. Turbidity current
18. Wind wave
    1. Rogue wave

This section contains 10 articles.

1. Glaciology
2. Basal sliding
3. Crevasse
4. Glacier (Level 3)
5. Iceberg (Level 4)
6. Ice sheet (Level 4)
7. Ice shelf (Level 4)
8. Methane clathrate
9. Permafrost (Level 4)
10. Sea ice (Level 4)

This section contains 46 articles.

1. Hydrology (Level 4)
2. Body of water
3. Discharge (hydrology)
   1. Streamflow
4. Groundwater (Level 4)
   1. Spring (hydrology) (Level 4)
   2. Aquifer
      1. Artesian well
   3. Groundwater recharge
5. Hydrography (Level 4)
6. Lake (Level 3)
   1. Alpine lake
   2. Dry lake (Level 4)
      1. Salt pan (geology)
   3. Glacial lake
      1. Proglacial lake
   4. Lake ecosystem
      1. Lake stratification
   5. Oxbow lake
   6. Pond (Level 4)
   7. Puddle
   8. Pluvial lake
   9. Rift lake
   10. Salt lake
   11. Underground lake
   12. Volcanic crater lake
7. Limnology (Level 4)
8. River (Level 3)
   1. Alluvial river
   2. Arroyo (watercourse)
   3. Avulsion (river)
   4. Bedrock river
   5. Distributary
      1. Braided river
   6. Confluence
   7. Drainage basin (Level 4)
      1. Endorheic basin
   8. Estuary (Level 4)
   9. River mouth
   10. River delta (Level 4)
   11. River ecosystem
   12. River source
   13. Stream
   14. Thalweg
   15. Tributary
9. Water cycle (Level 4)