WHAT  IS  GEOLOGY?

 

Geology is the study of the Earth.  Etymologically, that's literally what is means.  The first part, "geo-" is derived from "Gaea", the name of an ancient fake goddess of the Earth.  The second part is derived from the ancient word "logia" meaning "writing about" or "study of".

 

Geology is not just the study of rocks, despite the widespread perception that geology is the study of rocks.  Geology is the study of the Earth - the whole Earth.  What does the Earth include?

 

Geosphere - the solid Earth (= rocky portion of the Earth - crust + mantle + core, although some portions of those are liquid or somewhat soft).

 

Atmosphere - the gaseous layer of Earth occurring above the crust.  Earth's air includes ~78% molecular nitrogen (N2), ~21% molecular oxygen (O2), ~0.9% argon (Ar), plus scores of trace gases.

 

Hydrosphere - liquid water occurring in Earth's ocean basins, in rivers/streams/lakes/ponds, and as groundwater.

 

Cryosphere - glacial ice, principally occurring on Antarctica, Greenland, and at the tops of some mountain ranges.

 

Biosphere - the study of Earth's life forms is part of geology; biology is part of geology (although biologists won't readily admit this!).

 

Pedosphere - an understanding of Earth's soils ("dirt") is part of geology.

 

Magnetosphere - Earth has a magnetic field, generated by currents in the molten, outer portion of Earth's metallic iron-rich core.

 

Geology involves a thorough understanding of the entire Earth.  Many researchers refer to the inter-relatedness of all the "-spheres" listed above as the Earth system.  As such, some geologists have changed the name for "the study of the Earth" from geology to Earth system science.  There are several other synonyms for geology, including "geological science", "geoscience", and "Earth science".  All of these mean the same thing, and as such, I would suggest that the oldest and simplest term is the only correct term.  GEOLOGY.

 

Unfortunately, the definition of geology as "study of the Earth" is arbitrarily limiting.  Many scientists do planetary geology, which is the study of the geology of the various planets and moons in the solar system.

 


 

There are numerous specialties in geology - it's probably the broadest field in all of science.  Geology students and professional geologists have dozens and dozens of possible fields to be interested in.  A not-complete list is given below.

 

Aquatic geochemistry - study of the natural and pollution chemistries of water

Archaeological geology - study of the geology of archaeological sites

Atmospheric chemistry - study of the natural and pollution chemistries of air

Atmospheric physics - study of the physics of weather and other atmospheric phenomena

Atmospheric science - study of Earth's (or another planet's) atmosphere

Basin analysis - study of the origin and history of sedimentary basins (depositional centers)

Biogeochemistry - study of the interrelationship between life forms and natural chemical cycles

Biostratigraphy - study of layered rocks based on fossil content

Brachiopodology - study of modern and/or fossil brachiopods

Bryozoology - study of modern and/or fossil bryozoans

Chronostratigraphy - study of the absolute ages of layered rocks

Climatology - study of climate

Coal geology - study of the origin, composition, and occurrence of coal beds

Conodontology - study of conodonts (= phosphatic microfossils that were grasping spines in the mouths of an extinct group of chordates)

Coral paleoclimatology - study of ancient climates using information from fossil corals

Crinoidology - study of crinoids (= sea lilies - relatives of starfish)

Crystallography - study of crystals

Dinosaurology - study of dinosaurs

Earth science - study of the Earth

Economic geology - study of all Earth materials that have value in society

Engineering geology - study of & recognition of & accounting for site-specific and regional geology before, during, and after construction projects (buildings, roads, bridges, geothermal well fields at Ohio State University-Columbus campus, etc.)

Environmental geology - study of the relationship between geology and natural hazards or environmental concerns/problems

Environmental geophysics - study of near-surface geology using geophysical methods at the surface

Exploration geophysics - study of subsurface geology using geophysical methods at the surface to discover petroleum fields, ore deposits, etc.

Field geology - field gathering of geologic information and mapping of geologic units and structures

Forensic geology - study of solving crimes using geologic evidence

Genetic stratigraphy - study of the origin and age of discrete packages of layered rocks unconformably separated from other rock packages

Geoarchaeology - study of the geology of archaeological sites

Geochemistry - study of the chemical composition of & chemical reactions occurring in geologic systems

Geochronology - study of the absolute ages of rocks and geologic events

Geodesy - study of Earth measurements, tides, gravitational field, and upper geospheric movements

Geodetics - study of Earth measurements, tides, gravitational field, and upper geospheric movements

Geodynamics - study of the physics of plate tectonics, structural deformation, and glacial ice sheet formation & retreat

Geographic information systems - analysis and graphical representation of data tied to various geographic locations

Geoinformatics - study of the nature and graphical representation of geologic information tied to various geographic locations

Geological science - study of the Earth

Geology - study of the Earth

Geomathematics - study of the Earth using math

Geometallurgy - study of the geology and mineralogy behind variation in extraction styles of metals from ores during processing

Geomicrobiology - study of the relationship between micro-organisms and various geologic/geochemical phenomena; includes the study of extremophile microbes

Geomorphology - study of the morphology and origin of landforms

Geophysics - study of the physics of the Earth

Geoscience - study of the Earth

Geoscience education - study of how geology is taught in schools

Geostatistics - study of the use of statistics in solving geologic problems

Glacial geology - study of glaciers, their effects, and their deposits

Glaciology - study of glaciers

Gravimetry - study of the strength of and variations in Earth's gravitation field

Historical geology - study of the changes in the geosphere, atmosphere, hydrosphere, cryosphere, pedosphere, magnetosphere, and biosphere throughout the 4.55 billion years of Earth's history

History of geology - study of early geologic ideas and early geologists

Hydrogeology - study of surface water and groundwater

Hydrogeophysics - study of groundwater using geophysical methods at the surface

Ichnology - study of traces made by organisms

Igneous petrology - study of the origin, mineralogy, and chemistry of igneous rocks

Inorganic geochemistry - study of the non-carbon based chemistry of geologic systems

Invertebrate paleontology - study of fossil invertebrates (animals without a backbone)

Isotope biogeochemistry - study of the interrelationship between life forms and natural chemical cycles using isotopic information

Isotope geochemistry - study of the nature and origin of isotopic variations in geologic systems

Isotope geology - study of the nature and origin of isotopic variations in geologic systems

Isotope stratigraphy - study of vertical changes in the isotopic compositions of layered rocks

Limnogeology - study of inland bodies of water (ponds, lakes)

Limnology - study of inland bodies of water (ponds, lakes)

Lithostratigraphy - study of layered rocks based on rock type

Magnetometry - study of the strength and variation of Earth's magnetic field

Magnetostratigraphy - study of layered rocks based on their magnetic properties

Marine geology - study of the oceans

Medical geology - study of the relationship between geology and human health

Metamorphic geology - study of metamorphic rocks

Meteoritics - study of meteorites

Meteorology - study of weather

Micropaleontology - study of microfossils

Mineralogy - study of minerals

Mineral physics - study of the physical properties of minerals

Neotectonics - study of the geology and physics of modern and geologically recent (= post-Oligocene) plate tectonic processes and structural deformation

Oceanography - study of the oceans

Organic geochemistry - study of the carbon-based chemistry of geologic systems

Paleoanthropology - study of fossil hominids

Paleobiology - study of ancient life

Paleobotany - study of fossil plants

Paleoceanography - study of ancient oceans

Paleoclimatology - study of ancient climates

Paleoecology - study of the relationship between ancient organisms and their environment

Paleogeography - study of the geographic changes of continents and ocean basins through geologic time

Paleohydrogeology - study of ancient aquifers and ancient surface waters

Paleohydrology - study of ancient aquifers and ancient surface waters

Paleoichnology - study of traces left by ancient organisms

Paleomagnetics - study of the magnetic properties of rocks

Paleomagnetism - study of the magnetic properties of rocks

Paleontology - study of fossils

Paleooology - study of fossil eggs

Paleopedology - study of ancient soils (paleosols)

Paleoseismology - study of ancient earthquakes

Paleotectonics - study of the geology and physics of geologically ancient (= pre-Miocene) plate tectonic processes and structural deformation

Paleozoology - study of ancient animals

Pedology - study of soils

Petroleum geology - study of oil and natural gas

Petrology - study of the origin, mineralogy, and chemistry of all rock types

Phylogeny - study of the evolutionary relationships among modern and/or ancient organisms

Planetary geology - study of the geology of other planets, moons, asteroids, meteoroids, and comets

Precambrian geology - study of extremely ancient (older than 544 million years) geologic objects, events, and phenomena

Quaternary geology - study of modern and geologically recent (post-Pliocene) geologic objects, events, and phenomena

Reflection seismology - study of subsurface geology using information obtained from artificial, surface-originated shock waves that get reflected back to the surface from rock layers, faults, and other geologic contacts

Remote sensing - study of surficial geology using information obtained from a distance

Rheology - study of the flow physics of rocks, minerals, ice, magma, and water

Scolecodontology - study of scolecodonts (= microfossils of polychaete worm jaws)

Sedimentary geology - study of sediments, sedimentation, and sedimentary rocks

Sedimentary petrology - study of the origin, physical characteristics, and mineralogy of sedimentary rocks

Sedimentology - study of sediments and sedimentation

Seismology - study of earthquakes

Seismotectonics - study of the relationships among earthquakes, fault lines, and plate tectonics

Sequence stratigraphy - study of the subdivision of layered rock successions into discrete, genetically-related, unconformity-bounded packages

Soil science - study of soils

Speleology - study of caves

Stratigraphy - study of layered rocks

Stromatolitology - study of stromatolites (= large, layered structures built up by photosynthetic bacterial mats)

Structural geology - study of the geometry and origin of deformed rocks

Taxonomy - study of naming and classifying modern and/or ancient organisms

Tectonics - study of plate tectonics

Tectonophysics - study of the physics of plate tectonics

Trilobitology - study of fossil trilobites

Vertebrate paleontology - study of fossil vertebrates (animals with a backbone)

Volcanology - study of volcanoes

 


 

Home page