Glossary

Lava surface with jagged blocks

To removing atoms or ions from the surface of a solid material

Loss of ice from a glacier

Physical weathering caused by contact between moving rock fragments and larger rock surfaces

The lowest possible temperature, at which molecules have no kinetic energy

The increase in the rate of movement of an object

Gain of ice in a glacier

A silicate-bearing meteorite that lacks chondrules (spherical glassy fragments); achondrites

probably represent the remains of mantle material from planets in the early Solar System.

Acid, acidic: having a higher concentration of hydrogen (hydronium) ions than pure water

The resistance of a substance to seismic waves passing through it; acoustic impedance is a function of the substance’s density multiplied by the velocity of seismic waves

A continental margin that coincides with a plate boundary

The surface layer of sediment or rock above permafrost that thaws seasonally

The principle that events in the past can be explained in terms of physical, chemical, or biological processes and laws that operate at the present day

A type of lustre in which different wavelengths of light are refracted differently, typical of diamond

The sudden evolution of a diverse array of taxa from a single group in the wake of a major event in Earth history

A change to a system is adiabatic no heat energy is gained or lost during the change

The rate at which air cools with elevation as it rises adiabatically (without heat transfer) within the atmosphere. The adiabatic lapse rate may be expressed in degrees per kilometre of elevation.

The movement of the terminus of a glacier in the same direction as ice flow, so that more land is progressively covered by ice; Typically occurs when accumulation exceeds ablation.

Small particles or droplets suspended in the atmosphere.

Material composed of numerous rock fragments, as used by humans in construction

The proportion of light that is reflected from the surface of a substance

Alga (plural: algae). A photosynthetic eukaryote (plant) with simple unicellular or multicellular body structure, lacking leaves and vascular (water-carrying) tissues found in land plants.

A metal in group 1 of the periodic table, having one electron it its outer electron shell

A substance that absorbs positive hydrogen ions and/or contributes negative hydroxyl ions when dissolved in water, leading to a high pH.

Different minerals consisting of the same native element. (Synonymous with "polymorphs," but

used only for minerals that are native elements.)

A seimi-circular or triangular body of coarse sediment formed at a break in slope in a river system

A broad, short clumped cloud typically formed at moderately high altitudes.

A thin, laterally continous transparent cloud similar to stratus but formed at moderately high altitudes. Altostratus clouds typically allow sunlight to penetrate through.

A group of cephalopod molluscs with chambered shells, similar to modern nautiloids

A form of reduced nitrogen consisting of positively charged ions with one nitrogen atom bonded to four hydrogen atoms NH4+

The difference between the maximum and minimum value of a wave-like phenomenon. May

also refer to the difference between the maximum and the mean value.

A vesicles in an igneous rock such as pumice that has been infilled with minerals

Breaking down something into its component parts

Mountain belt that formed due to the subduction of oceanic underneath continental lithosphere.

Named after the Andes mountain range; also called a cordilleran orogen.

An active mountain range (orogen) in western South America

A negatively charged ion, that has gained one or more electrons relative to its constituent atom(s)

Referring to the South Pole and the surrounding region

The southernmost area of the Earth that experiences constant darkness at the Summer solstice, and constant daylight at the Winter solstice

An eastward current formed by the movement of oceanic gyres north of Antarctica.

The southernmost continent on Earth

Generated by humans

The system comprising the human species and the parts of the Earth that humans have modified

A region of high pressure with diverging air circulation at low altitude, clockwise in the northern hemisphere, counterclockwise in the southern hemisphere

The point in the Earth's elliptical orbit that is closest Sun

Describes the zone in the ocean where no light penetrates

The path of one of the Earth’s magnetic poles over geologic time, as it appears relative to a

given continent

Impermeable unit within the Earth's crust that slows or stops the flow of groundwater

Unit within the Earth's crust that is a reservoir of groundwater usable by humans

Units in the outer part of the Geosphere that can supply water at a rate useful to humans

A form of calcium carbonate CaCO3; that is produced by many organisms but is less stable than the more common polymorph calcite.

A group of Prokaryotic single-celled organisms that diverged from Bacteria early in Earth history

An eon early in Earth history prior to the Proterozoic from ~4 Ga to 2.5 Ga

When a body is partially or completely immersed in a fluid, it experiences an upthrust equal to the weight of fluid displaced.

Referring to the North Pole and the surrounding region

A positive feedback phenomenon whereby more of the effect of climate change is felt in Arctic or Antarctic latitudes than is felt at the equator.

The northernmost area of the Earth which experiences constant daylight at the summer solstice, and constant darkness at the winter solstice

A jagged ridge between two glacial valleys

An inert gas, element 18

A confined aquifer from which water rises toward the surface under pressure

A member of the largest phylum of invertebrates, the Arthropoda, characterised by their jointed legs and chitinous exoskeletons. Arthropods include insects, spiders, crustaceans. and several other groups

Structures build by humans along the banks of rivers, with the purpose of preventing or reducing flooding.

The selective breeding of organisms with traits desired by humans in order to produce offspring more suitable for human purposes. Examples include varieties of dogs and crops.

Near vertical descent of ash from the atmosphere to the surface of the Earth.

A small object which orbits the Sun in the Solar System, ranging in size from 1 m to 850 km

A belt of small objects (asteroids) whose orbit lies between those of Mars and Jupiter

The layer of the mantle lying beneath the lithosphere and capable of plastic flow

The average distance between the Earth and Sun; 1.5 x 109 metres

The envelope of gas surrounding a planet

The study of the atmosphere of a planet (usually Earth).

A ring-shaped reef

The total number of particles (neutrons plus protons) in the nucleus of an atom

The heavy, positively-charged central body in an atom of an atom.

The number of protons in the nucleus of an atom of an element, equal to the number of electrons if the atom is not ionized

Atomic weight (relative atomic mass): The mass of an atom expressed on relative a scale in which the most common isotope of Carbon is given a value 12.

A halo of metamorphic rock developed around an igneous intrusion, resulting from contact

metamorphism.

Visible light produced in the southern hemisphere by solar wind’s interaction with particles in Earth’s thermosphere; southern lights

Visible light produced in the northern hemisphere by solar wind’s interaction with particles in Earth’s thermosphere; northern lights

An organism that captures its own energy, usually by photosynthesis

The number of atoms or molecules in a mole of a substance.6.022 x 1023

Prokaryotic single-celled organisms; distinguished from Archaea by the chemistry of their cell membranes and ribosomes.

Layers of iron-rich minerals and chert that were particularly common in the Proterozoic Eon

A depositional landform, typically of sand or gravel, in a river

A beach that is partly or completely separated from the land by a lagoon or inlet

A reef that is separated from the land by a shallow lagoon or shelf

The centre of gravity of a system; the pivot point about which a system rotates when freely spinning.

The extrusive product of mafic magma. Basalt has a fine grain-size and a dark colour.

Water transported into a channel through groundwater flow into the base of the stream

The elevation at which a river enters the sea or a lake

Describes a substance that is able to accept hydrogen ions or generate hydroxyl ions. Alkaline.

Pluton larger than 40 km2 in area.

Describes maps of the ocean based on seafloor depth.

Measurement of the depth of the sea floor.

An elongated body of sediment along a coastline, formed by waves

A layer of sedimentary rock more than 1 cm thick

Sediment carried along the water-bottom (usually of a river) through rolling, sliding, and saltation

The presence of layers at centimetre or larger scale, having distinct composition an/or texture, typical of sedimentary rocks

A feature formed by wind or water current flowing over loose sediment

Referring to the ocean’s bed, and the fauna that live there.

A typical process for the formation of snow. Vapour condenses first as supercooled water droplets. As the temperature falls the droplets release vapour which condenses as ice.

High-speed electrons released during the conversion of a neutron to a proton in an unstable

isotope

A negatively charged ion with the formula HCO3-, or a compound containing such ions

Describes a statistical distribution that has two peaks or modes

The flow of an element through not only the Biosphere and and other spheres of the Earth

The study of the spatial distribution of plants and animals

A collection of ecosystems having similar characteristics of climate, terrain, and energy flow

Deposition by organisms of solid inorganic material obtained from dissolved material in their environment

The Earth system that comprises all living things and their non-living remains

A subdivision of strata recognized on the basis of characteristic fossil forms.

A delta with multiple distributaries separated by bays

Double refraction; the splitting of light into two polarised beams refracted in slightly different directions, yielding a double image

A metamorphic rock formed at high pressure and relatively low temperature; named for the presence of the blue sodium-bearing silicate mineral glaucophane.

A metamorphic environment characterized by high pressure and relatively low temperature;

named for the presence of the blue sodium-bearing silicate mineral glaucophane.

Seismic waves that travel through the interior of the Geosphere

Text that is written with thicker lines than the rest of the text on a page

Having a salinity intermediate between that of freshwater and seawater.

Braided streams have multiple branches that branch and rejoin

A sudden change in slope from steep to gentle.

Brine

Water with a concentration of salt exceeding that of normal sea-water

Rock with gravel-sized angular grains

A magnesium silicate mineral theoretically dominating the mineral content of the lower mantle;

(Mg,Fe)SiO3

Water having a salinity greater than normal sea water (35 parts per thousand)

Describes a material or process of deformation in which strength is suddenly lost across a fracture plane or planes

Deep-sea sediment comprising mainly the calcium-carbonate skeletons of foraminifera and coccolithophores

CaCO3; the most common mineral form of calcium carbonate

Compound with the formula CaCO3, the main component of limestone and the shells of marine

animals

A broad crater with a rim that is low in relation to the crater diameter

Highly explosive eruption that largely collapses a conical volcano leaving a broad circular crater

The break-off of icebergs from glacier ice that is at sea level

The adaptive radiation of animal forms in the marine environment of the early Paleozoic. Modern body plans rapidly appeared in the Cambrian, along with unique, extinct forms.

Covalently-bonded compounds of carbon, hydrogen, and oxygen, in which hydrogen and oxygen are present in the same proportions as in water

Element 6, symbol C, contained in all living things. The most abundant isotope is carbon-12, containing 6 protons and 6 neutrons

A cycle describing the flow of the element Carbon through the Earth system.

A gas in which each molecule combines one atom of carbon with two of oxygen; formula: CO2

A stable isotope of carbon with seven neutrons that makes up a minority of natural carbon atoms.

An unstable isotope of carbon with eight neutrons. Carbon-14 is used for radiocarbon dating.

A substance with a high content of reduced carbon

Negatively charged ions with the formula CO₃ ²⁻; or, a substance containing such ions

Fine-grained sediment composed mainly of microscopic calcium carbonate grains

A flat continental shelf where the rate of carbonate sedimentation is able to keep up with

subsidence producing great thicknesses of shallow-marine carbonate rock

A continental shelf where most of the sediment is composed of carbonate mineral grains rather

than clastic, silicate grains

A shoreline where carbonate minerals form most of the sediment

A process whereby the chemical weathering of silicate minerals to form carbonate minerals controls the amount of silica, carbonate, and carbon dioxide in the Hydrosphere and Atmosphere.

A weak acid formed in solution when carbon dioxide dissolves in water: formula H2CO3;.

Positively charged ion

The smallest unit of living things, including genetic material and cytoplasm surrounded by a cellular membrane.

A polymeric carbohydrate found in plant del wals and bacterial biofilms; the most abundant organic substance in the biosphere

Mineral matter deposited by groundwater in the pore space of a rock.

The current era in geologic time from ~65 Ma to the present day.

Soft limestone formed mainly from the calcite plates of unicellular planktonic plants called

coccolithophores.

Changes that occur in living things over time as a result of natural selection

Short notches, transverse to movement direction, found on glacially eroded or faulted surfaces

Changes in the mineral composition of rocks as they are exposed to air and water at the Earth's surface, producing new minerals and dissolved material

A form of autotrophic metabolism where an organism obtains energy from chemical reactions without the assistance of sunlight

A hard rock composed of very fine interlocking grains of silica SiO2.

The edge of an igneous intrusion where rapid cooling due to contact with cold host rock

produces finer-grained rock than is found in the interior of the intrusion.

Clay almost exclusively composed of the mineral kaolinite; used in the manufacture of porcelain

Warm orographic wind adjacent to the Rocky Mountains of Canada. Cooler air descends from high altitudes and is warmed by adiabatic compression.

An organic compound responsible for the absorption of light during photosynthesis.

Organelles within plant cells that contain chlorophyll, and are responsible for photosynthesis in plants and photosynthetic microbes; chloroplasts are descended from free-living cyanobacteria.

A type of meteorite characterized by small, roughly spherical particles of glass or former glass, known as chondrules

Small spheres interpreted as the remains of liquid droplets from the early Solar System.

Animal belonging to the phylum Chordata, characterized by a stiff dorsal rod or notochord accompanied by a hollow nerve cord; includes all vertebrates and a number of smaller, related groups.

Chromium oxide, a dark mineral often concentrated in the layers of layered igneous intrusions.

Formula Cr2O3

A small, steep volcano composed of loose tephra fragments known as scoria

A bowl-shaped glacial valley that is approximately as short as it is wide (equant)

A small glacier in a cirque – a bowl-shaped depression on the side of a mountain formed by glacial erosion.

High-altitude clouds composed of ice particles, but having a clumped appearance similar to lower-altitude cumulus.

A layer of ice cloud in the upper troposphere, typically above 6 km, that is thicker and more continuous than cirrus.

Wispy, high altitude clouds that typically form above 6 km up to the tropopause. They are typically ice-particle clouds.

A category in taxonomy larger than an order but smaller than a phylum

A solid fragment of sediment

Sediment formed from the solid products of weathering

The texture of clastic sedimentary rocks, where individual grains rest against each other without

interlocking

Clay (grain-size): Clastic sediment with a grain-size finer than 4 μm, deposited under very low-energy conditions.

Clay (sediment or rock) A sediment or soft rock composed largely of clay minerals finer than 4 μm, used in the manufacture of pottery and porcelain.

Clay mineral: A fine-grained hydrous mineral; clay minerals are mainly sheet silicates, most characteristically

formed by chemical weathering

Cleavage (mineral): The behaviour of a mineral that splits along flat surfaces controlled by its crystalline structure

Cleavage (rock):The behaviour of a fine-grained rock like slate that splits along flat surfaces because of the

preferred orientation of its mineral grains.

Long-term trends in Earth’s atmosphere which may affect weather, but take effect for much longer. Climate is weather averaged over periods longer than a single year

An atmospheric scientist who studies long-term changes in the Atmosphere

A lakes that receives input, yet lacks an outflow other than evaporation.

A system that exchanges energy but not matter with its surroundings

A visible mass of aerosol water droplets suspended in the Atmosphere

Carbon-rich sedimentary rock formed from solidified organic material that originated as peat

A layer, or bed, of coal

Small oval scale of calcium carbonate secreted by a coccolithophore

Unicellular phytoplankton that secretes plates (coccoliths) of calcium carbonate to cover their bodies. Chalk is formed from these plates.

A boundary between cold and warm air where the cold air is advancing into the area previously occupied by warm air. The denser cold air pushes the warm air upwards, causing precipitation.

Glacial ice that is below its freezing point at the base of a glacier

A mountain chain formed where continental crust enters a subduction zone, coming into contact with another continent or an oceanic volcanic arc.

A mineral property of limited usefulness in diagnosis. Minerals quartz may display a wide range

of colours.

Hexagonal structures formed due to cracks in thick lava flows that have shrunk during cooling.

A small body in the Solar System with composition including large components of ices; comets develop a tail as they approach the Sun along eccentric elliptical orbits

Interacting populations of different species

Reduction in volume of a sediment or soil due to the expulsion of air or water

A typically conical volcano consisting of layers of both tephra and lava; stratovolcano.

A curved or ribbed shape, seen in the fracture surfaces of many minerals and a few rocks such as chert and volcanic glass

Having a parallel orientiation to adjacent rock structures.

An anthropogenic mixture of cement and coarse sediment (sand or gravel), used in

construction.

The phase change of gas to liquid, or gas to solid, usually due to decreasing temperature.

A process of movement of heat or electricity which does not involve the movement of the material through which it travels

The transfer of electric energy from one part of an object to another due to a difference in electric potential between the two parts

The transfer of heat energy from one part of an object to another due to a difference in temperature between the two parts

A lowering of the water table in an unconfined aquifer caused by the withdrawal of groundwater at one or more wells

An aquifer where the upper boundary is defined by an aquiclude.

A unit that is impermeable to groundwater flow

Units of low permeability that confine groundwater

Coarse clastic sedimentary rock composed of gravel-size (>2 mm) grains.

Water that has remained trapped in sedimentary rock since its formation as sediment

A principal in mechanics in which the product of mass times velocity is conserved

Metamorphism spurred by physical contact with high-temperature magma. Grain size increases, while fabric may be eliminated. Thermal metamorphism.

A process of orogenesis that occurs where a plate carrying continental crust enters a subduction zone at an oceanic volcanic arc. Continental crust undergoes shortening and thickening, producing mountains.

A process of orogenesis that occurs where two converging plates both carry continental crust. Continental crust undergoes shortening and thickening, typically producing high mountains.

Relatively low-density, thick crust that underlies the continents and the continental shelves.

A theory that explains features of the Earth by slow movement of the continents over geologic time. The theory of continental drift has largely been incorporated into the later theory of plate tectonics, which also explains movements of the ocean floor.

The fringe of a continent were it shares a boundary with oceanic crust.

A gently-sloping zone of deposited sediment at the base of the continental slope, transitional the

deep-sea floor or abyssal plain.

An area of shallow sea (<200 m) at the edge of a continent, underlain by continental crust.

Inclined sea-floor descending from the edge of the continental shelf down to the continental rise.

A cyclic motion of gas or liquid as it is heated. As the material is heated, it rises due to the lower density. Once it moves far enough from the heat source, it begins to cool, causing it to sink again, returning it to the heat source.

Hydrocarbon deposits where a porous reservoir rock has enough permeability to yield oil or natural gas when penetrated by drilling.

The boundary between two plates moving towards one another. Convergent boundaries are the sites of subduction of one plate beneath the other.

Sedentary suspension feeders, closely related to sea anemones and jellyfish, which may build exoskeletons of calcium carbonate. They are major reef-builders in Earth’s oceans.

A mountain range at the western edge of North or South America, formed by plate convergence.

Mountain-building episodes that occurred along the North or South American continental margin with the Pacific Ocean.

The central part of the Earth below about 2900 km from the surface, composed largely of metallic iron

A major discontinuity and seismic reflector ~2900 km below the Earth's surface, separating the silicate mantle from the metallic core

Cores (drilling): Narrow cylinders of sediment recovered, typically from lake beds or the sea floor during scientific investigation or during the search for mineral deposits

The apparent deflection of objects travelling over the surface of a rotating sphere, because of different rotation speeds at different latitudes

The match the sedimentary layers displayed by two or more different stratigraphic columns.

Described bonding of atoms by the sharing of electrons

Atomic bonds wherein two atoms share electrons so as to acquire full outer electron shells.

The core of a continent that has been stable since at least 500 Ma

Slow, distributed movement of Earth material either down a slope (mass wasting), or within the Earth (as part of tectonic deformation)

A deep crack in the surface of glacier ice

A thin, surface layer of the Earth that lies above the Moho; differentiated into thicker, lighter continental crust and thinner, denser oceanic crust

Marine arthropods with chitinous shells augmented with calcium carbonate.

A large group of Arthropoda with calcite-reinforced exoskeletons

A system containing all Earth's ice

The regularly repeating three-dimensional arrangement of atoms and/or ions in a crystalline solid material such as a mineral

A category of crystal lattice distinguished by its symmetry

Intrusive rock in which minerals that formed early have sunk and accumulated at the bottom of a magma chamber

Towering clumped rain-producing cloud, typically terminated at the top with an anvil-shaped ice-cloud. Typically produces lighning and thunder.

Cloud with clumped domed tops and flat bases formed at low altitude where rising air reaches its dew point to form water droplets.

The temperature at which a mineral acquires the ambient magnetic field orientation during its cooling; for the common magnetic mineral magnetite the Curie point is 570oC.

Daughter isotope

An isotope produced as a result of isotopic decay.

Single-celled prokaryotes capable of photosynthesis and the release of oxygen. Cyanobacteria were responsible for the original oxygenation of the Earth’s atmosphere.

A region of low pressure with converging air circulation at low altitude, clockwise in the southern hemisphere, counterclockwise in the northern hemisphere

Complex fluid mixture fills the cells of prokaryotes; in eukaryotes it surrounds the organelles, nucleus, and ribosomes.

A unit of permeability. A permeability of one darcy allows one cubic centimetre per second of fluid having a viscosity of one centipoise through a sample with a cross-section of one square centimetre under a pressure gradient of one atmosphere per centimetre. The SI equivalent of one darcy would be 9.87 x 10⁻¹² m².

An isotope that is a product of a nuclear decay reaction

Mass transport in which large fragments are supported by the strength of a wet mud matrix that flows

.

The breakdown of an atomic nucleus of an unstable isotope.

A constant that relates the number of atoms that undergo radioactive decay per unit time to the

total number of remaining atoms; typically represented by Greek lambda (λ)

The direction relative to the north of Earth’s magnetic field.

An expression for geologic time that emphasizes the challenge of imagining enormous lengths of time involved

A deep, linear feature of the ocean floor that marks a convergent plate boundary

The finest-grained clastic sediment on the deep-sea floor.

Change in the shape, size, orientation, or position of materials over time in the Geosphere

A characterization of a mutation that harms an organism’s ability to survive or reproduce

A sediment deposit formed from the flow of a channel into a standing water body.

Dates obtained from the number of annual rings in tree wood, typically obtained from core samples.

The production of atmospheric nitrogen from ammonium ions by aerobic bacteria.

Mass per unit of volume of a substance.

The accumulation of sediment in an area distant from the site of erosion.

Landscape features formed from deposited sediment.

A hydrogen isotope with an atomic mass number of 2, in which each atom contains one proton and one neutron, represented 2H or D

For an undersaturated body of air, the dew point is the temperature at which the air would become saturated. The dew point is always equal to or lower than the actual temperature of the air.

A fault where the side opposite to an observer appears to be moving to the observer's right.

A change in sediment after it is deposited

Referring to changes in a sediment after it is deposited

A crystalline mineral form of elemental carbon the hardest known mineral.

Sediment formed from the silica skeletons of unicellular plants called diatoms

Photosynthetic, unicellular plankton that inhabit oceans and lakes. Diatoms are notable for their siliceous skeletons of opal.

Stress that acts with different intensity in different directions

A process that causes a body of magma or rock to change composition, most commonly by the settling of early-formed minerals during cooling

A data set of points that are equally spaced in two horizontal directions (usually E and N); each point is associated with an elevation.

The magnetic field produced by a magnetized body with north and south poles on opposite sides

(1) The total rate of flow passing through a channel, calculated as a volume per unit time;

(2) Any exit of water from groundwater onto the Earth's surface.

Geological features that are not parallel to one another

Material that travels in flowing water in solution, rather than as solid particles

Reduced arbon that is carried in water in solution, including carbohydrates and amino acids

Channels that branch from a main channel in the downstream direction, typical of alluvial fans and deltas

Links within proteins between sulfur atoms in amino acids, that are important in defining protein shape and structure

The movement of two objects (such as portions of the Earth’s lithosphere) away from one another.

The boundary between two plates moving apart from one another; divergent boundaries are commonly the sites of rift valleys and ocean-floor spreading.

Deoxyribonucleic acid: A double-stranded nucleic acid that preserves genetic information

A solid shape with twelve faces

The largest taxonomic category recognized; living things are commonly divided into three domains (Archaea, Bacteria and Eukarya) but in some classifications two domains (Prokarya and Eukarya) are recognized

The erosion of the base of a steeply sloping stream, particularly near the headwaters of a river.

A downward flow of water, typically due Ekman transport that forces water towards a coast

The force that operates between a flowing liquid and an adjacent solid

The total area that delivers water into a single channel or waterbody.

A border between drainage basins.

A deposit of calcium carbonate formed by evaporation of water in caves

A clast of rock that has fallen from floating ice into sediment below

A former forest where relative rise in the level of the sea or a lake has led to the death of trees; often a result of eustatic sea level rise during glacial melt.

A tear-drop-shaped hill, a subglacial landform formed by ice sheets moulding subglacial sediment

The lustre of a mineral whose surfaces reflect light poorly. Similar to earthy

A large bedform, typically with a wavelength > 1 m, formed by a current of water or air moving over sediment

A suspension of mud-sized particles in the troposphere by powerful winds.

A body in the Solar System with diameter larger than 850 km yet smaller than the planet Mercury

Dyke (USA — dike): A sheet-like igneous intrusion that is not concordant with any layering in its host rock

Metamorphism caused mainly by the extreme physical deformation of a rock; high strain produces small grain sizes and strong fabrics.

The third planet from the Sun in the Solar System, and the principal object of study for geoscientists; the only planet known to possess life.

A debris flow on the land surface

The study of the Earth as a set of interlinked systems, integrating subjects such as atmospheric science, oceanography, geology etc.

An event in which stored elastic energy is rapidly released by sudden movement on a fault

surface

The chance that an earthquake of a given magnitude will occur in a given area during a given time interval.

The lustre of a granular mineral whose surfaces reflect light poorly. Similar to dull

The length of the long axis in relation to the length of the short axis of an ellipse; a measure of the difference between the ellipse and a perfect circle.

A marine invertebrate in the phylum Echinodermata characterized by a skeleton of calcite crystal plates and a water vascular system; includes starfish and sea urchins.

The plane of Earth’s orbit around the Sun.

A metamorphic rock formed at high pressure and moderate to high temperature; components of feldspar become dissolved in red garnet and green pyroxene

The position of a species in an ecosystem, including its physical environment, predators, and energy sources

The study of relationships between groups of organisms interacting with their physical environment

A community plus its associated non-living systems (soil, air, water etc.)

A diverse group of late Proterozoic extinct organisms of uncertain relation to modern animals

The helical path of a downward water stream due to the Coriolis effect

The net transport of water at 90 degrees an the original wind direction as a result of the Coriolis effect.

Warming of the central and east Pacific Ocean surface resulting in the supression of normal December upwelling off the coast of South America

Deformation where strain and stress are proportional. Energy is then stored in elastically deformed rocks and released when the stress is reduced.

A common type of energy movement characterized by oscillating electric and magnetic fields, including radio, infra-red, visible, and ultraviolet light, x-rays and gamma rays

A three-dimensional shape with only elliptical cross-sections

A scientific description or hypothesis drawn directly from observation or experiment

A moraine formed at the terminus of a glacier.

The transfer of energy through the various spheres and systems of the Earth

El Niño southern oscillation (ENSO) is an oscillating behaviour of the atmosphere–ocean system defined by changes in the temperature of east-Pacific surface waters over periods of several years

The amount of energy in a system that is not available to do physical work; also a measure of the degree of disorder in a system.

The largest subdivision of geologic time

A point on the Earth's surface located vertically above the focus, or hypocentre, of an earthquake

Having approximately equal length and width

A west-to-east (in mariner's terms, westerly) current that flows along the equator, opposite to the north and south equatorial Currents.

Westward currents (easterly in mariner's terms) formed by the movement of gyres north and south of the Equator.

For a chemical or physical reaction, a state in which the reaction occurs in both directions at the same rate; the amounts or concentrations of the reacting materials do not change over time.

Line on a glacier that separates the accumulation zone from the ablation zone

A time in an Earth year when which the tilt of the Earth's axis is perpendicular to the line between the Earth and the Sun, resulting in equal lengths of daylight and darkness

The removal of material from a site of weathering on the Earth's surface.

A block of rock that has been moved by a glacier so that it appears foreign to the bedrock that it rests on

Vertical eruptions of tephra from a volcanic vent, which may further expand in the atmosphere

A ridge of well-sorted sand and gravel deposited by streams flowing beneath ice

A partially enclosed bay or river mouth in which freshwater and seawater mix

A unicellular or multicellular organism with cells that contain a distinct nucleus surrounded by cytoplasm with organelles

Having cells that contain a distinct nucleus surrounded by cytoplasm with organelles

Relating to global sea level, and its rise and fall through time

The combination of evaporation and transpiration that transfers water vapour into the Atmosphere from the land surfaces

The conversion of a substance from a liquid state to a gas

Minerals or rocks produced by

precipitation of minerals from high-salinity water (such as seawater) during evaporation

The combined processes by which water is transferred from liquid at Earth’s surface to vapour in the atmosphere, comprising both physical evaporation and transpiration by plants

Changes in the characteristics of organisms, and the Biosphere as a whole, over periods of many generations.

Having undergone evolution

The splitting of solid rocks into sheets roughly parallel to the surface, due to volume changes and stresses during uplift, weathering and erosion

A reduction in the amount of material at a rate proportional to the amount of remaining material.

A way of representing large or small numbers using a coefficient or mantissa (typically a number with one digit to the left of the decimal point) multiplied by an exponent (a power of 10)

Describes deformation, particularly at plate boundaries, in which rocks are stretched horizontally; divergent.

A quantity, such as heat energy or mass, which varies in proportion to the amount of material considered

Forcings that originate outside the system under consideration

Describes igneous rock formed from magma that cooled at the Earth’s surface; volcanic.

The cloud-free centre of a tropical cyclone where winds are at their calmest.

The wall of cloud surrounding the eye of a tropical cyclone where winds are particularly fast

The structure of a rock defined by the preferred orientation of mineral grains or other components parallel to a line or plane, or both

A taxonomic category larger than a genus but smaller than an order.

A body of sediment formed at a break in slope on the edge of a water body, combining characteristics of a delta and an alluvial fan

A fracture in Earth’s crust where bodies of rock may slide past each other.

The animal life present in a region

Waste material expelled from an animal's gut

The process whereby a change in one part of a cycle causes changes throughout the cycle, which then affect the part originally changed

An abundant group of framework silicates containing aluminum together with some combination of

potassium, sodium and calcium

Igneous rock or magma with more than about 65% silica. Felsic rocks typically contain quartz

with potassium and/or sodium feldspar.

A feature of atmospheric circulation at moderate latitudes; air flows towards the equator at low altitude and away from the equator in the upper troposphere.

Silicate minerals that contain large amounts of magnesium and/or iron, typically in solid solution, and a relatively low amount of silica.

A stage in sexual reproduction of metazoa at which gametes fuse to form a cell with double the number of chromosomes.

The distance over which wind can blow across the surface of a body of water to develop waves.

The gathering of samples and information by investigators working outdoors
 

Ice particles formed by the loss of air in snow that has been resting on the surface of the Earth for more than a year

The ability of a rock to split into thin flakes or sheets parallel to sedimentary layers.

The eruption of magma as lava through cracks in the crust.

The transformation of atmospheric nitrogen into a form more usable by organisms.

Nitrogen is described as fixed when it has been converted from its atmospheric form into a form more usable by organisms

A valley glacier that flows into a submerged valleys and terminates in the sea.

The land surrounding a river channel which becomes submerged during high-discharge events (floods).

The plant life present in a region

Any movement of material down a slope in which the material behaves as a fluid, deforming continuously as it moves.

Angiosperms; plants that reproduce via flowers as reproductive organs and fruits as dispersal units.

Movement of fluid material along the surface of the Earth.

Pertaining to rivers.

The rate of flow into or out of a reservoir in a cycle

The point within the Earth where an earthquake begins, and from which seismic waves radiate

The focus points of an ellipse are two special points that lie on the long axis of the ellipse, symmetrically on either side of the centre at a distance apart f = √(p2-q2) where p and q are the major and minor diameters of the ellipse. The more eccentric the ellipse, the farther apart are the two foci.

A fabric seen in metamorphic rocks where grains or components are aligned parallel to a particular plane.

A simplified diagram of consumers in a community, showing the transfer of energy through trophic levels.

A diagram showing all the producer–consumer predatory relationships between organisms in a community.

A colloquial name for pyrite, due to its resemblance to gold.

The block of rock that lies below a sloping fault surface.

A diverse group of marine single-celled organisms whose preserved exoskeletons (or tests) may be preserved as fossils in marine sediments.

In physics, an influence that can cause an object to change velocity

An effect that changes the balance of fluxes in a system and therefore cause the system to depart from a steady state

A depression in the lithosphere created by the isostatic effect of an adjacent mountain belt.

A layer of rock that appears on a geologic map

Remains of ancient organisms, buried in rocks

Carbon-rich substances found in the geosphere and formed from the remains of past-living organisms. Fossil fuels contain sufficient concentration of reduced carbon to produce usable heat when burnt in air.

Having a disproportionate concentration of an isotope due to that isotope's heavier or lighter weight

Fractionation describes a process whereby a partial change of a substance from one phase to another results in a change in composition.

Any surface across which a rock or mineral loses its strength, that is not controlled by the mineral structure

A form of sea ice consisting of separate needles, typically 3–4 mm long, floating in water

A phase change from liquid to solid, due to decreasing temperature.

For a wave-like phenomenon, the number of waves that pass a point in one second; measured in hertz (Hz).

The resistance between two solids moving against one another

Elongated reefs that form adjacent to and parallel to a shoreline, without wide lagoon to separate the reef from land.

A border between air masses of different temperatures; usually associated with precipitatoin and changes in wind direction.

The mechanical weathering effect of water as it freezes to form ice, due to expansion.

The mechanical weathering effect of water trapped in spaces just below the surface of the Geosphere, raising rock or soil as it freezes to form ice.

The mechanical weathering effect of water in thin cracks as it freezes to form ice, splitting rocks apart as a result of expansion.

Solid Earth material with pore spaces filled by ice

Billion years before the present.

Intrusive mafic igneous rock.

Streams that increase their discharge in a downstream direction as a result of base flow from groundwater.

Lead sulphide (PbS), a mineral displaying a cubic habit and metallic lustre.

A group of hard silicate minerals with isolated silicate tetrahedra containing combinations of aluminum, iron, magnesium, calcium and other elements. Garnets are most common in metamorphic rocks

Computer models for the atmosphere which which work as hypotheses for predictions about future weather and climate.

Units of DNA in an organism which code for particular proteins, and, therefore, particular characteristics.

Evolution that does not arise from selection pressure, but rather from chance.

The taxonomic group above species and below family.

A pore space partially filled by minerals.

A equipotential surface that approximates the Earth's surface. Gravity pulls at 90 degrees to the geoid surface everywhere.

A scientist who studies the Geosphere using on observations of Earth materials

The study of the Geosphere, particularly the parts that can be studied by direct observation at the surface.

The north and south poles of Earth's magnetic field

A scientists who studies the interior of the Earth mainly through remote sensing methods using physical properties of the Earth.

The study of the Earth using physical properties to probe parts that cannot be directly observed.

Geologists and geophysicists.

The solid Earth

Air that flows in a direction parallel to isobars, as a result of a balance between the pressure-gradient force and the Coriolis effect.

A curve on a graph that relates temperature to pressure or depth within the Geosphere

Energy originating from within the Earth, either from radioactive decay or from the orignal heat trapped at the planet's formation

The rate of rise of temperature with pressure or with depth below the surface.

A billion years before present. Symbol: Ga

A billion tonnes, equivalent to 1012 kilograms; sometimes called a petagram.

Geographic information systems

Pertaining to ice or glaciers. During cold episodes of Earth history, glacial periods are periods of more ice cover.

The oscillation of Earth’s climate between periods with more and less ice.

Masses of ice capable of slow movement over the land surface

Describes environments with rivers derived from melting of glacier ice

Describes lake environments associated with glaciers

A scientist who studies glaciers and ice in the Earth system

Describes environments in the sea that are influcence by nearby glacier ice.

A blue chain-silicate mineral formed during the recrystallization of ferromagnesian minerals and feldspar under high-pressure conditions.

Computer-based models of how the atmosphere behaves. Although these models can be very complex, they represent simplified versions of the real atmosphere. Global climate models are typically types of general circulation model. The same abbreviation (GCM) applies to both.

Global positioning system (GPS): A satellite-based navigation system that has additionally provided evidence of plate motion

A list of terms that contains a definition or explanation of each

High-grade coarse-grained metamorphic rock formed mainly of silicate minerals, typically displaying a strong banded fabric.

A dense yellow metal element (Au), atomic number 79.

A supercontinent assembled during the Proterozoic Eon, that was incorporated in the larger supercontinent Pangea during the Paleozoic Era. Parts of Gondwana form modern South America, Africa, Antarctica, Australia, and India.

global positioning system

Metamorphic grade: The degree to which a rock has been metamorphosed, mainly as a consequence of temperature.

Grade (mineral deposits): The concentration of a desired element in rocks

A bed which has coarse sediment at the base but becomes progressively finer-grained towards to top..

The average diameter of a particle within a rock.

Coarse-grained felsic igneous rock containing quartz and potassium feldspar.

Coarse-grained silicate metamorphic rock formed by thermal metamorphism.

A soft form of mineral carbon containing sheets of hexagonally linked carbon atoms weakly bound together

Sediment consisting of particles larger than 2 mm in diameter.

A device used to measure the slight variations in gravity seen at Earth’s surface due to differing rock density below.

A fundamental force between all masses in the universe

Variations in the force of gravity due to differing rock densities below.

The downward movement of a sediment-water mixture due to gravity. Debris flows and deep-sea turbidity currents are examples of gravity flows.

The mass emission of free molecular oxygen into the atmosphere by cyanobacteria at approximately 2.4–2.0 Ga.

A warm state of Earth’s climate, without continental ice sheets.

The absorbtion of outgoing infra-red radiation by atmospheric gases, leading to heading of the Earth’s atmosphere.

A compounds in the Earth’s atmosphere which absorbs infra-red radiation, preventing or delaying its escape into space.

A dark green metamorphic formed through the metamorphism of a mafic igneous protolith, without strong fabric.

The amount of inorganic carbon, or the amount of energy, captured by autotrophs in an ecosystem

The line on the sea-floor between glacier ice that is floating and glacier ice that is resting on the bottom

Water that occupies spaces within the Geosphere

In geologic mapping, several formations that occur together

Increase in size of a living organism, or part of a living organism

A combination of thermohaline and surface currents in the North Atlantic that transports warm water from SW to NE, warming Europe.

A mineral form of hydrated calcium sulphate (CaSO₄·2H₂O)

Circular movements of a fluid; typically applied to Coriolis-driven movements in the Atmosphere and oceans.

A circulation of air that first rises near the equator before cooling and descending at the "horse latitudes"

The amount of time required for a mass of a particular isotope to decay until only 50% of the parent isotope remains.

The mineral form of table salt (NaCl)

The segment of the ocean’s depth where the most rapid increase in salinity with depth.

Group 17 of the periodic table. Elements with 7 electrons in their outer shell.

The flow of rock salt within the Geosphere.

A small glacial valley that enters a larger glacial valley high on the side of the larger valley

The block of rock that lies above a dipping fault surface.

The extension of the head of a river valley in an upstream direction, resulting from downcutting, coupled with downslope movement of material.

The upstream part of a river or stream, closer to the river source.

The total thermal kinetic energy of all the molecules in a body or system

Element 2, an inert gas

; A mineral form of oxidised iron (Fe₂O₃)

Organisms which consume other organisms in order to release energy through respiration.

The mountain range, or orogen, at the boundary between the Indian subcontinent and the rest of Asia; currently the highest mountain range in the world

The application of historical data to a climate model in order to test the predictive ability of the model against present observations

The genus containing modern humans and our closest extinct relatives.

The species containing modern humans

A jagged peak formed in glaciated terrain where three or more arêtes meet

A mostly fine-grained metamorphic rock without fabric formed through contact metamorphism.

The rock units into which magma intrudes.

A localized region at the Earth's surface located above an unusually hot part of the mantle.

A tropical cyclone a in the Atlantic and East Pacific

Wind speed >120 km/hr; the wind speed required for a tropical system to be considered a tropical cyclone.

A process of pumping pressurized fluid into rock, causing fractures that increase permeability

The height of an equivalent water column that would produce the observed potential for groundwater movement; groundwater flows from the location of high to low hydraulic head.

A compound constructed from carbon-carbon and carbon-hydrogen bonds.

Element 1, the most abundant element in the Universe and in the Sun

Weak bonds between polar molecules, seen in water for instance, where the positive poles of one molecule are drawn to the negative poles of another.

A positively-charged hydrogen atom that has lost its only electron; responsible for the formation of hydronium ions H3O+ in water.

A reduced form of sulfur that is emitted from hydrothermal vents where it provides a source of energy for chemosynthetic autotrophs in the absence of sunlight and oxygen.

A scientist who studies groundwater

The study of water within the Geosphere

Graphs of river discharge over extended periods of time, indicating the rise and fall of total flow.

A scientist who studies the flow of water at the Earth's surface

A reaction involving the breakdown of a mineral through the action of water which provides hydrogen and hydroxyl ions.

A positively charged ion H3O⁺ formed by the addition of a positive hydrogen ion to a molecule of water.

All the free water on Earth, in the forms of water vapour, liquid water, and solid ice.

Pressure; stress that acts equally in all directions, particularly when applied by water.

Hydrothermal describes groundwater that has been heated by geothermal energy

Concentrations of minerals deposited by hot groundwater.

Openings, typically on the ocean floor, from which hot water or steam is able to escape.

A negatively charged ion OH⁻ formed when a water molecule loses a hydrogen ion.

The focus of an earthquake; the point within the Earth from which seismic waves begin to radiate.

An statement that explains or predicts observations, and is therefore testable

A graph representation of the prevalence of different elevations across Earth’s surface.

Water in its solid, crystalline form

A period of Earth history during which large areas are covered by glaciers

Small (<50,000 km²) areas of continental ice cover that are not confined by topograpy.

Cylindrical samples of glaciers acquired by drilling.

An area of coalesced valley glaciers; similar to an ice cap, but constrained by topography and lacking a dome-like shape.

A large masses of glacial ice unconstrained by topography.

A floating extension of a land-based glacier

A V-shaped mass of ice formed by repeated shrinkage, cracking, infiltration of water, and freezing; found in periglacial areas.

A positive feedback wherein the melting of ice reduces the albedo of Earth’s surface, allowing further warming and additional ice melting.

A floating mass of ice shed from the terminus of a glacier into water

The Earth’s climatic state during times of cyclic expansion and retreat of ice sheets.

Relating to or formed from molten rock.

Bodies of igneous rock formed when magma solidifies within the Geosphere.

Rocks formed from the cooling of molten material (magma).

Having near-zero permeability

Describes a stream channel formed by downcutting of underlying rock, especially when it preserves shapes (eg meanders) formed before the downcutting episode.

The steepness of Earth’s magnetic field.

The resistance of an object to changes in movement, requiring that a force is necessary to change its velocity

Heat energy in the form of electromagnetic waves with relatively wavelengths from ~1 mm to ~700 nm, the limit of visible light

Describes carbon compounds that lack carbon–hydrogen bonds.

The amount of solar radiation received by a unit surface area in a given time period

Earthquake intensity measures the amount of ground shaking at a point. Intensity typically decreases away from the focus of the earthquake.

A value which is independent of the amount of material under consideration, such as temperature or chemical concentration.

An interval during an ice age where warmer temperatures cause worldwide glacial retreat.

An igneous rock or magma with between 52% and 65% silica

Forcings that originate within the system under consideration.

A low pressure band in the Earth’s atmosphere lying approximately along the equator

A process whereby magma solidifies within the Geosphere.

Igneous rock formed when magma solidifies within the Geosphere.

An atom or group of atoms that has lost or gained one or more electrons, resulting in a net positive or negative electric charge

Bonds between atoms formed by the transfer of electrons from one atom to another. The resulting negatively and positively charged ions are attracted together.

Of atoms or groups of atoms: Having lost or gained electrons producing a positive or negative charge.

Addition or removal or of electrons to/from atoms or groups of atoms, forming ions

The layer of Earth’s atmosphere, including the mesosphere and thermosphere, where solar radiation may add or remove electrons from atoms, creating ions

Iron that has lost two electrons from each atom. Formerly known as ferrous iron

Iron that has lost or shared three electrons from each atom; oxidized iron. Formerly known as ferric iron.

A minority of meteorites, composed primarily of iron material probably derived from the cores of early proto-planetary bodies in the Solar System.

The solar energy flux, typically measured as a rate of energy flow per square metre at the top of the Earth's atmosphere

A chain of volcanic islands formed above a subduction zone.

A system that exchanges neither matter nor energy with its surroundings

The behaviour of upper layers of the Earth as if floating on the more deformable Asthenosphere below; lower density material corresponds to higher elevations.

The behaviour of upper layers of the Earth as if floating on the more deformable Asthenosphere below; lower density material corresponds to higher elevations.

The phenomenon in which the lithosphere rises when a surface load (such as an ice sheet) is removed.

The phenomenon in which the lithosphere falls when a surface load (such as an ice sheet) is added.

Isotopes of an element are atoms that have the same atomic number but different atomic mass, because of different numbers of neutrons in the nucleus

The use of unstable isotopes with known half-lives to calculate the approximate age of a sample.

West-to-east winds moving at the top of the troposphere, following a pressure gradient. The jet stream typically meanders, and roughly follows to the polar front.

Relating to planet Jupiter and the other outer planets.

The four outermost planets in the Solar System, having small rocky cores wrapped in thick atmospheres and a multitude of natural satellites.

The fifth planet from to the Sun, and the largest

Kilo-annum; thousand years before present.

A body of water-deposited sediment formed on top of or between glacier ice bodies

A glacial landform made of sand or gravel deposited by water flowing along the edge of a glacier

A clay mineral formed of hydrous aluminium silicate. AlSi₂O₅(OH)₄

A type of landscape including features produced by solution of rock

The descent of cold, dense air cooled by higher-altitude glaciers towards lower ground.

An early supercontinent that may have formed around 2.7 Ga in the late Archean.

Johannes Kepler. A German natural philosopher who determined three laws of planetary motion, relating to each planet’s elliptical orbit about the Sun.

Organic matter in sediment or sedimentary rock that is insoluble in organic solvents and that may form oil and gas if heated.

A lake or depression in a periglacial area, typically formed as a result of the melting of a stranded ice block during glacier retreat

Thousands of years before present; ka.

Ultramafic tuff produced by explosive volcanic eruptions sourced from the mantle; the main source of diamonds.

Large cylindrical structures preserving ultramafic tephra sourced from the mantle; the main source of diamond.

Having to do with movement

The energy possessed by a mass in motion.

A high taxonomic level in most classifications of organisms; kingdoms rank above phyla but below domains.

Extrusive ultramafic volcanic rock.

A belt of mainly comets hypothesized to orbit around the Sun beyond the orbit of Neptune

A phase of El Niño southern oscillation (ENSO) in which west-Pacific rise of air is intensified and the equatorial east Pacific is unusually cold

An area of shallow water protected from large waves by a barrier reef or atoll.

A debris flow generated by volcanic activity

A body of surface water that is isolated from the world's oceans.

Lamina (plural laminae): a thin layer (less than 1 cm thick)

Sheet-like; applied to flow of fluids, it describes flow along sub-parallel lines, lacking the gyres typical of turblence.

Wind that flows from land to sea, typically caused as a high-pressure region forms on land as air cools rapidly at night

Distinctive landscape shapes characteristic of particular Earth-surface processes

Large fragments of tephra 2 to 64 mm in diameter.

Regions of the Earth where large amounts of magma (usually mafic) have been generated in a geologically short time.

A time about 20 thousand years ago when glaciers reached a maximum extent.

Energy released or absorbed in phase changes.

Volcanic explosion that expels tephra in a near-horizontal direction.

The widening of a river valley by a low-gradient river. This process typically occurs when the bends of rivers reach the valley sides.

An accumulation of till or rock fragments along the edge of an Alpine glacier

Magma (molten rock) that has emerged onto the surface of the Earth.

Small, steep-sided volcanoes typically formed by felsic lava.

A body of liquid lava ponded in the crater or caldera of a volcano.

Bodies of mafic magma that cooled within the Geosphere, in which layers of different composition have formed.

The downwind side of a landscape feature

Sinistral: fault motion such that the far wall of a fault appears displaced to the observer's left

A family of flowering plants (including peas and beans) capable of fixing nitrogen through symbiosis with nitrogen-fixing bacteria. Nodules within the legumes’ roots provide an anaerobic environment in which nitrogen fixation can occur.

An organic polymer found within the cells walls of plants, and especially in wood.

Fine-grained calcium carbonate

Sedimentary rock composed mainly of calcium carbonate

Nutrients which, when scarce, prevent cell division or growth from occurring, even in conditions where other nutrients are abundant of other nutrients.

The fabric seen in metamorphic rocks where grains or other components are oriented parallel to a line.

Organic, chain-like compounds, including oils, fats, and waxes, that are non-polar as whole, though they may have polar and nonpolar ends. As a result, lipids are not easily soluble in water, and are important for cells in forming cell membranes.

A boundary on a phase diagram separating fully liquid material from material with some solid components, marking the completion of melting.

The solidification of sediment into solid sedimentary rock

Sedimentary material that has solidified into sedimentary rock

Element 3, the lightest metallic element

The rigid outer part of the Geosphere that is divided into plates, consisting of the crust and outer layer of the mantle

A boundary typically between 50 and 250 km deep within the Mantle, separating rigid plates above from slowly deforming material below

The portion of the Lithosphere below the Moho and above the Lithosphere-Asthenosphere boundary

A short period of cooling from 1400 to 1850 CE. The little ice age was not a true glacial interval, but rather a temporary decline in temperatures across the world.

The zone of the shore that is exposed to air dry during low tide, but submerged during high tide.

A rounded part of a delta’s depositional structure.

The elevation of a river at a point where the speed of flow is near zero, typically at a lake.

A plot of elevation versus downstream distance in a river.

the gradual movement of water parallel to the shore resulting from obliquely impinging waves.

The transportation of sediment by longshore currents.

Streams that lose discharge downstream by recharging groundwater.

Seismic surface waves in which motion is horizontal and perpendicular to the wave propagation direction

A zone in the upper mantle where both P- and S-waves slow down, corresponding approximately to the Asthenosphere

The portion of the mantle below ~650 km, below the transition zone.

Lustre (USA: luster): The quality of light reflected from a mineral’s surface.

Mega-annum; Million years before the present.

Fossils large enough to be viewed by the unaided eye.

Of silicate minerals and rocks, having large amounts of magnesium and iron; mafic rocks have silica contents of 45–50%.

Igneous rocks with low amounts of silicates, of only 45-50%, in their original magma.

Molten rock

Changes in the composition of magma due to the removal of certain chemical components, often as a result of mineral settling.

Regions where Earth’s magnetic field is stronger or weaker than predicted by a simple dipole model of the magnetic field.

A region within which the direction of magnetic force can be determined

Geologically rapid exchange of the polarity of Earth’s magnetic north and south poles.

An iron oxide mineral with the formula Fe₃O₄

A measure of the energy release from an earthquake, scaled to the logarithm of displacement at a standardized distance.

A class of vertebrates characterized by lactation, three middle ear bones, and hair. Mammals make up the majority of megafauna in the Cenozoic Era.

The layer within the Earth or other inner planet that overlies the core and makes up the majority of the planet, composed chiefly of magnesium- and iron-rich silicates

An uprise of mantle material that cause a hotspot in the Earth’s lithosphere.

The mantle that in a subduction zone rests above the subducted lithosphere, and is overlain by a volcanic arc.

The metamorphosed product of limestone. Marble contains coarse, interlocking calcite grains, sometimes together with other minerals.

The fourth planet from the the Sun

The difference between the amount of ice that a glacier accumulates and the amount lost by ablation.

A device used to measure and count atomic masses.

Processes that move dense solid material down slopes on the surface of the Geosphere due to the force of gravity.

The transformation over time of raw organic matter into fossil fuel.

An interval during the late 17th to early 18th century CE when sunspots were at a minimum

River behaviour characterized by large changes in channel direction (bends).

related to movement and forces

The physical breakdown of rock into smaller particles at the surface of the Geosphere.

A linear accumulation of till in the middle of an Alpine glaciar, formed by the merging of two lateral moraines

Million years before present; Ma.

The two-stage process of cell division in sexual reproduction, whereby four daughter cells are created each with half of a full set of chromosomes.

Black coloration seen as a variation in moths.

Barriers composed of phospholipids that are barriers within and around cells.

The nearest planet to the Sun, and the smallest planet.

The boundary separating the mesosphere and thermosphere, where the temperature of the atmosphere reaches its lowest point

The layer of Earth’s atmosphere directly above the stratosphere, divided from it by the stratopause. In the mesosphere, the temperature decreases with elevation.

An era in the Phanerozoic Eon of Earth history, from about 200 Ma to about 65 Ma

A type of RNA responsible for the transfer of genetic information transcribed from DNA in the nucleus to ribosomes in the cytoplasm, where proteins are synthesised

Metamorphic rock derived from basalt.

The capture, transfer, and use of energy by complex carbon-containing molecules in living things

Relating to the properties of metals, substances that tend to conduct electricity and to form bonds by losing electrons

The form of bonding in metals, whereby a cloud of free electrons is held by a lattice of metal ions.

High-quality reflection of light from the surfaces of a mineral.

Describes rock formed through transformation of older rock by heat and pressure, without melting

Environments of formation metamorphic rock characterized by the stability ranges (in temperature and pressure) of particular mineral assemblages.

Rocks that have recrystallized while solid, as a result or heat, pressure, and/or deformation

The transformation of a rock in the solid state due to high temperature and/or pressure.

Metamorphic rock derived from sandstone.

A state wherein a system is not in equilibrium, but an input of energy would be required to move it to an equilibrium state.

Metamorphic rock derived from volcanic rock.

Multicellular animals

The extraterrestrial rock mass that has reached the Earth’s surface through impact.

Bodies in the Solar System smaller in size than asteroids, with diameters less than a metre.

Atmospheric scientists who study short term changes in the atmosphere known as weather.

Meteoroids as they enter Earth’s atmosphere. Friction with the atmosphere causes a glowing tail to form in the wake of the meteoroid.

A gaseous compound of carbon and hydrogen CH4. Methane is the principal component of natural gas. In the Earth's atmosphere it acts as a greenhouse gas.

A group of sheet-silicate minerals with a sheet-like habit and perfect cleavage.

Fossils requiring magnification for study; fossils too small for the unaided eye to see features.

Elements or compounds that, while essential for life functions, are only required in small quantities.

Elevated regions on the ocean floor centred on divergent plate boundaries.

Gneisses formed through partial melting, containing a mixture of igneous and metamorphic material.

Repetitive variations in the Earth’s tilt, axis orientation and elliptical orbit shape, that cause climate forcing.

A unit of permeability equal to one thousadth of a darcy

A naturally occurring crystalline solid with a fixed or limited range of compositions

Organelles within the cells of eukaryotes are the site of respiration within eukaryotic cells

The most common process of cell division whereby both daughter cells acquire full copies of the parent cell’s genetic material

A simplified or theoretical version of a complex natural system, either a physical model using analog materials, or a mathematical model run on a computer.

A scale for measuring the intensity of an earthquake

Mohorovičić Discontinuity: The boundary at the base of the Earth’s crust where seismic P-waves abruptly increase in velocity.

Moho: The boundary at the base of the Earth’s crust where seismic P-waves abruptly increase in velocity..

The rate of cooling as mass of moist air rises without exchanging heat with its surroundings, while water vapour in the air condenses. The rate of adiabatic cooling is offset by the release of latent energy during condensation

An amount of an element or compound such that the number of grams of the substance is equal to the atomic or molecular weight; one mole of any substance contains a number of atoms or molecules equal to Avogadro’s number.

A method by which DNA from two or more organisms is compared to determine their relatedness

A phylum of invertebrates which typically produce shells composed of calcium carbonate; Mollusca include snails, clams, and octopus (a group that has secondarily lost the shell)

A scale of earthquake size that depends on the amount of slip and the slipped area of the fault surface. The moment magnitude is commonly calibrated to the older Richter scale but gives a more precise measure of earthquake size.

Climate characterised by oscillating dry and extremely wet seasons, caused by northward and southward movement of the intertropical convergence zone (ITCZ)

Earth's only natural satellite; also (with lowercase m) any natural satellite of a planet

Natural satellites of planets are sometimes known as moons.

An accumulation of glacial till

Accumulations of till associated with glaciers.

The descent of cool, dense air from high ground into adjacent valleys

Sediment composed of particles with a diameter less than 1/16 mm.

A flow of fine-grained sediment mixed with water

Clastic sedimentary rock with a grain-size below 1/16 mm

Sea ice that has lasted more than one year

Having a body comprising numerous cells separated by membranes from one another

Changes in the genetic material carried by a cell or an organism caused by copying errors during cell division, by exposure to certain chemicals and types of radiation, or other essentially random processes

A dynamic metamorphic rock formed through the extreme deformation that has reduced the size of its mineral grains

Minerals or other substances composed wholly of a single element.

A feature of cliffs that have been undercut as a result of weathering and erosion, producing a hole or window through solid rock.

Hydrocarbon-rich gas derived from sedimentary organic matter.

A raised bank along the edge of a river channel due to deposition during flooding.

Objects in the solar system that orbit around a planet

The evolutionary process whereby the environment favours that survival of particular characteristcs in a population

A tidal phenomenon caused by a 90 degree angle between the Sun and the Moon, resulting in reduced tidal range.

Interstellar clouds of dust and gas

A cycle in which the products of a process act as inputs inhibiting the same process, reducing the effects of the process.

A feature of a graph in which the value of the dependent variable decreases when the independent variable increases; in cartesian x-y coordinates, the graph slopes downward to the right.

The eighth planet from the Sun.

The zone of the ocean that is covered by water at all tidal stages directly above the continental shelf, with a maximum depth of about 200 metres.

A neutrally-charged particle within an atom’s nucleus

Partially compacted snow in its first year.

Isaac Newton: an English natural philosopher who developed the laws of gravity and inertia

An organism’s position in an ecosystem.

A continuous thin sheet of ice formed by freezing of calm water

Horizontal low-altitude cloud layers (stratus) that produce steady precipitation.

Negatively charged ions formed by the oxidation of nitrogen; NO³⁻.

Element 7. In the molecular form N2, the most abundant gas in Earth’s atmosphere.

The process by which nitrogen is exchanged between the Atmosphere, Hydrosphere, and the Biosphere, undergoing oxidation and reduction reactions in the process

A gas composed of nitrogen and oxygen, produced as part of the nitrogen cycle, which acts as a greenhouse gas in the atmosphere; N₂O

Materials such as fossil fuels and minerals which do not form at a rate fast enough to replace their consumption by humans.

A process in which the two light atomic nuclei join together to form a single more massive nucleus, releasing energy

Particles or electromagnetic waves released by the decay of atomic nuclei in unstable isotopes.

Energy required to form the first stable particle or droplet of a substance (usually water or ice fomed during a condensation process)

Long, chain-like molecules (polymers) composed of linked units called nucleotides. Two major kinds of nucleic acids exist: DNA and RNA.

An membrane-bounded body within eukaryotic cells that contains the genetic material in the form of DNA

The central part of an atom, carrying positive charge and almost all of the atom's mass

A supercontinent which may have formed 1.8 billion years ago in the early Proterozoic Eon.

An exposed rock mountain top projecting through an ice sheet or ice cap

Elements or compounds essential for life processes.

A ellipsoid with circular symmetry about an axis which is shorter than its other radii; a flattened sphere.

Diagonal; at an angle that is not a multiple of 90°.

The angle at which the Earth’s axis of rotation is tilted towards the ecliptic.

Thinner crust is composed mostly of mafic rock.

The reagion beyond the continental shelf, where water depth is greater than 200 m.

The study of Earth's seas and oceans

Liquid Petroleum; organic matter that has undergone burial and subsequently been transformed into hydrocarbon-rich liquid.

A region within the Geosphere where liquid petroleum is present within porous, permeable rock.

Fine-grained sedimentary rock which holds a large proportion of hydrocarbons.

A silicate of iron and/or magnesium with separate silicate tetrahedra in its structure; (Mg,Fe)₂SiO₄.

A spherical collection of comets outside the orbits of all other planets, at distances between 2,000 tand100,000 astronomical units from the Sun.

Fine-grained deep-sea sediment composed of the remains of the skeletons of plankton.

Non crystalline silica, sometimes including a small proportion of water; SiO₂·nH₂O.

Lakes with an outlet, such a stream, with discharge equal to that of the lake’s input; open lakes typically contain fresh water.

A system that exchanges both matter and energy with its surroundings

Sections of mafic or ultramafic rock from oceanic lithosphere that have been uplifted on land.

The study of minerals under the microscope in order to identify them.

Changes in Earth’s obliquity, eccentricity, and the precession of equinoxes which affect the flow of energy through Earth systems

A taxonomic group of organisms larger than a family but smaller than a class

Structures within cells that accomplish important functions, typically relating to respiration, production of organic compounds, or reproduction

Any reduced carbon compound containing carbon–hydrogen bonds (or, rarely carbon–halogen bonds); elemental forms of carbon (with only carbon–carbon bonds) are regarded as inorganic.

Matter containing reduced carbon that originated in a living organism.

A mountain belt formed by shortening of the crust.

A mountain-building process that occurs as crust shortens during the convergence of the lithosphere.

The rise of air as wind blows over hills or mountains

Wind patterns associated with mountains

At right angles or 90°

A channel carved by a sudden release of glacial meltwater

The layer of the core directly below the mantle, composed mainly of liquid iron.

A narrow glacier at the edge of an ice sheet that is confined by topography

Gravel and sand deposited by meltwater beyond the terminus of glaciers.

Flow of water in a sheet over the land surface, without channel formation

Describes a situation where a substance (e.g. water vapour) is more concentrated in a mixture (e.g. air) than the amount that would be in equilibrium with a separate phase (e.g. liquid water or solid ice)

A lake formed when a meander channel is abandoned during hte evolution of a river.

The combination of an element with oxygen, or more generally, any chemical process resulting in electron loss

An element has different oxidation states when it can lose or share different numbers of electrons to form ions

Oxidised or oxidized: The state of an atom that has lost one or more electrons during a chemical reaction; named because oxygen is the most common remover of electrons.

Carbon which has lost or shared all four of its outer shell electrons with oxygen

Element 8. In the molecular form O2, the second most abundant gas in Earth’s atmosphere.

A compound consisting of three oxygen atoms O3 which exists in small amounts in the atmosphere due to both natural and anthropogenic activity.

Seismic body waves in which the vibration direction is parallel to the propagation (travel) direction.

Sea ice that covers more than 70% of the sea surface with slabs metres to kilometres across

A ropy lava surface formed when high-temperature flows of mafic lava cool.

A scientist who studies the remains, lives, and evolution of ancient living things

The study of fossil plants

The study of preserved magnetism in ancient rocks

The study of fossil animals; often used to describe the study of all fossils, including plants, where “paleobiology” would be more strictly correct.

The first era of the Phanerozoic Eon, in which multicellular organisms prominently radiated in the Cambrian Explosion, and multicellular life emerged onto land

A stage in the development of sea ice, characterized by roughly oval ice masses 30 cm – 3 m in diameter

Pangea (UK: Pangaea): A supercontinent formed during the late Paleozoic Era and dispersed during the Mesozoic and Cenozoic eras

The practice of shaking sediment grains in water to separate gold and other other high-density minerals.

A new collection of objectives, methods, and theories for a scientific discipline, developed during a scientific revolution

An unstable isotope which decays and yields a daughter isotope.

Melting of rock material to produce a mixture of solid and liquid.

The pressure exerted by a single gas within a gas mixture; the partial pressure of each gas is proportional to its fraction of molecules in the mixture.

Rock material that is a mixture of solid and liquid

A continental margin that does not coincide with a a plate boundary.

Geometric patterns that form on surfaces experiencing intense freezing and thawing.

Carbon-rich material formed from compressed plant remains; a first stage in coal formation.

Describes the open water column of the ocean; the environment away from the seafloor in which planktonic and nektonic organisms live.

The carbon-nitrogen bonds between amino acids that build peptides and proteins.

Gem-quality olivine

Utramafic rock composed mostly of pyroxene, usually together with olivine

The landscape surrounding glaciers.

The furthest from the Sun of the Earth in its elliptical orbit.

A visual representation of the known elements, by order of their atomic number. Columns represent elements having similar outer-shell electron configurations, and hence similar chemical properties

Material near the Geosphere surface that remains frozen for two or more years.

The ability of a solid to and allow fluid to move through it.

Naturally occurring liquid and gaseous hydrocarbons: Oil and natural gas.

A volume of porous rock within the Geosphere that contains oil or natural gas in sufficient quantity to be extracted

The standard scale of a substance’s acidity or alkalinity; minus the logarithmic concentration of hydrogen ions; acids have low pH; alkalis (bases) have high pH.

The current eon, following the Proterozoic, from about 539 Ma to the present day, characterized by abundant remains of muticellular organisms

The part of a system that is separated from other parts by distinct boundary surfaces; for example water exists in three phases: solid ice, liquid, and vapour, which do not mix.

The line or surface separating phases in the real world, or in a "phase diagram" representing the stability conditions of different phases.

The transition of a compound from one phase to another, typically in response to a change in temperature or pressure.

A graphical representation showing the conditions of temperature, pressure, or composition in which different phases are stable

Lipids involving a phosphate (PO₄)³⁻ group that gives one end of the molecule hydrophilic characteristics. Phospholipids are essential to the formation of cell membranes.

The fifteenth element of the periodic table, essential to living things in the formation of membranes and the transfer of energy

Relating to the zone where sunlight can penetrate into a waterbody.

The visible surface of the Sun.

The production of reduced carbon compounds from water and carbon dioxide using light as an energy source, carried out by cyanobacteria, many algae, and plants.

Metamorphic rocks intermediate in grain-size between slate and schist

A taxonomic group larger than a class but smaller than a kingdom.

Weathering that forms fragments of rock, without chemical change.

free-floating plants

A glacier formed when one or more valley glaciers flow out into a broad lowland or a larger valley.

Masses of mafic rock formed when mafic lava in the ocean rapidly cools by contact with water, forming balloon-like bodies.

An ice-cored hill found in a permafrost environment

Mineral deposits formed at the Earth's surface by sedimentary processes, typically the concentration of dense minerals by water flow.

A large, approximately spherical body (diameter greater than 850 km) of rock, liquid and/or gas in orbit around the Sun or another stars

Organisms that live floating or suspended in water

Organisms capable of suspension within the water column due to their small size

A high-temperature form of matter wherein the electrons of each atom are freed from the nuclei.

Continuous deformation of crystalline materials that takes place after a yield stress is exceeded

A rigid, moving part of the Lithosphere

A theory that the Earth has a lithosphere that is divided into relatively rigid moving plates that interact along plate boundaries

Portions of a craton that have been covered in sedimentary rock.

Six metallic elements with similar properties: Ruthenium, Rhodium, Palladium, Osmium, Iridium and Platinum.

Glacial plucking describes a process where a moving glacier removes bedrock fragments that have become surrounded by ice

A vertically hanging thread suspending a weight, used to define the vertical direction using the force of gravity.

A dwarf planet once considered the ninth planet from the Sun.

Large igneous intrusions

A data set of arbitrarily located points, each of which is represented by three coordinates, typically representing an easting, a northing, and an elevation

The inner edge of a river’s meander, where sediment can accumulate due to the slower flow of water.

The phenomenon whereby changes in the energy cycle have greater effect near the poles

Close to either the North Pole or the South Pole

A molecule with distinct positive and negative electric charges on either end

Low altitude polar winds that move air from east to west and towards the polar front.

A low-pressure belt where warm air from the tropics and cold air from the pole converge, typically producing cloud and preciptitation

Microscopic grains containing the male reproductive cells of plants, dispersed through air or by pollinating insects

Long, chain-like molecules with repeating components.

Minerals with the same chemical composition, yet a different structure.

A glacier with both cold-based and warm-based ice in different areas or at different times

Having a very wide range of grain sizes

Multiple individuals of one species living in the same area

The proportion or percentage of space in a solid that may be filled by fluids.

Igneous rocks with both fine and coarse mineral grains.

Copper sulphide deposits typically associated with porphyritic igneous rock.

A cycle in which the products of a process act as inputs increasing the activity of the same process

An evaporite rock composed mainly of potassium-rich minerals that precipitated from evaporating brine.

The level to which water would rise if a well were drilled into a confined aquifer

The rotation of the Earth’s tilted axis of rotation, which causes a change in the position and timing timing of the solstices and equinoxes relative to the axes of the Earth's elliptical orbit

Water or ice condensed from the Atmosphere that falls on the Earth's surface

The hypothesized nebula where the Sun and Solar System condensed from more dispersed dust and gas

The force per unit area exerted by a fluid on its surroundings

The dissolution of mineral grains due to compressive stress.

The flow of air from a region of high pressure to one of low pressure.

Porosity developed at the time a rock is formed

Autotrophs such as plants and phytoplankton that capture energy from their inorganic environment, represent the first trophic level in an ecosystem

An order of mammals that includes lemurs, monkeys, great apes, and humans.

A principle which states that strata were initially formed as approximately horizontal layers, parallel to the Earth's surface.

A principle in geology which states that the younger strata formed above older strata.

Formed in the environment immediately outside the terminus of a glacier

The counterclockwise rotation (when viewed from above Earth's north pole) that a majority of objects in the Solar System show.

The expansion of a sediment body into the sea as a result of high sediment supply (e.g. from a river).

In map making (cartography) projection is the process that transforms the 3-dimensional Earth onto a 2-dimensional page or computer screen.

Unicellular organisms whose cells lack a nucleus and complex organelles

Molecules consisting of chains of amino acids linked by peptide bonds, that perform innumerable tasks within and outside cells

The eon before the Phanerozoic, from 2500 to about 539 Ma, during which atmospheric oxygenation, the evolution of multicellular organisms, and Snowball Earth conditions occurred.

Unicellular eukaryotes that are not plants, fungi, or animals; protists fall into multiple taxonomic groups

The original rock-type from which a metamorphic rock was formed

A particle found in the nucleus of all atoms: protons carry a positive charge.

All of the material in the primeval Solar System which did not condense directly into the Sun. This material would instead form the planets, their natural satellites, the asteroids, meteoroids and comets.

In biogeography, provinces refer to areas having distinct fauna and/or flora because of barriers to migration

Information that is not a direct measurement of a physical quantity such as temperature, but which allows the value of that physical quantity to be estimated.

A sedimentary basin formed as at releasing bend on a fault such as a transform fault, where motion is near-horizontal.

Igneous rock with a foamy texture formed by volatiles in magma that left abundant vesicles in the rock as it cooled.

The zone within the ocean’s where there is the greatest rate of increase in density with depth occurs.

A mineral sulfide of iron FeS₂ that has yellow colour and metallic lustre.

Describes products of explosive volcanic eruptions that produce rock fragments.

Fluid mixtures of tephra and hot gas that quickly travel down the flank of a volcano

A group of mainly ferromagnesian single-chain silicate minerals common in mafic rocks

Information gathered only through description, without a numerical measurement.

Information gathered as numbers or amounts (for instance, temperature and distance).

Silica SiO₂ in its most common mineral form.

Metamorphic rock consisting largely of quartz, commonly formed by metamorphism of sandstone. (Sandstones that are unmetamorphosed but cemented by quartz are sometimes termed orthoquartzite, in which case metaquartzite can be used to distinguish the metamorphic rock.)

The most recent and current period of the Cenozoic Era, beginning about 2.6 million years ago. The Quaternary included significant glacial and interglacial intervals.

Infra-red radiation released by heated objects

The effect of carbon dioxide on the absorption and reflection of solar irradiance as it reaches Earth’s atmosphere.

The tendency of unstable isotopes to decay and release radioactive particles and gamma rays.

A group of unicellular marine plankton that construct silica skeletons that settle to the ocean floor

A form of siliceous ooze originating from the exoskeletons of Radiolaria

Radiometric or isotopic dating: determination of the age of a substance using amounts of elements involved in radioactive decay

A region of dry conditions on the downwind side of a mountain belt, due to precipitation of moisture as air moves over the mountains.

Elevated terraces along shores that arise uplift, typically due isostatic rebound following the removal of glacial ice.

Divisions recognized between coal types, based on increasing carbon content.

Seismic surface waves that produce vertical motions of the ground surface.

Bodies of till left by successive positions of a glacier terminus during glacier retreat of a glacier.

The addition of water over time to a groundwater reservoir

The average time between successive floods greater than or equal to a specified magnitude.

The state of an atom when an additional electron is added during a reaction; opposite of oxidation

Carbon that has gained electrons by bonding with other carbon atoms and/or hydrogen

The removal of oxygen or the addition of hydrogen to an element or compound, or, more generally, any chemical reaction that results in a gain of electrons

A raised, wave-resistant mound or ridge on the sea-floor, formed mainly of calcium carbonate deposited by organisms such as corals and algae

A phenomenon affecting all kinds of waves, whereby waves impinging obliquely on a boundary where their velocity changes experience a change in the direction of wave propagation

An area groundwater flows out through the surface of the Geosphere, for example at springs or as baseflow into streams.

Metamorphism that affects large areas of orogenic belts, produced by temperature, pressure and deformation

Weathered material that remains in its original position, without removal by erosion. Regolith mixed with plant material is called soil.

The vapour pressure of water in air at a given temperature divided by the saturation vapour pressure at the same temperature.

A group of theories in physics that state that the laws of mechanics and the speed of light are the same for all observers, even if those observers are moving relative to each other

A bend on a fault where the two walls of the fault move slightly apart

Permanent magnetism that was acquired at the time of rock formation and preserved until the present day.

Materials or energy supplies, useful to humans, that are replenished at a rate comparable to that of human consumption.

The copying and replication of molecules and organisms

Resources that can be exploited economically under present conditions.

The average time that a molecule remains in a reservoir; obtained by dividing the size of the reservoir by the flux in or out of the reservoir

Naturally occurring accumulations of useful material in concentrations and amounts that make extraction by humans currently or potentially feasible.

The oxidation of reduced (organic) carbon compounds by an organism to yield energy, carbon dioxide and water

Bends along the sides of a fault where both sides push slightly together.

The movement of the terminus of a glacier in the opposite direction to ice flow, so that less land is progressively covered by ice; Typically occurs when ablation exceeds accumulation.

The clockwise rotation (when viewed from above Earth's north pole) that a minority of objects in the Solar System show.

A solid shape the faces of which are all parallelograms.

A hard extrusive felsic igneous rock, the fine-grained equivalent of granite.

A measure of earthquake magnitude based on displacement at a standardized distance; in modern work, largely superseded by moment magnitude

One of the driving forces of plate tectonics, caused by the tendency of plates to move down the flanks of mid-ocean ridges because of the force of gravity.

A belt of stretched lithosphere, typically marked by one or more fault-bounded valleys

Stretching of the lithosphere along a belt marked by faults

Dextral: fault motion such that the far wall of a fault appears displaced to the observer's right

A narrow current of water flowing offshore, supplied by longshore currents.

The diversion of water from one stream into another channel, as a result of progressive river erosion (usually headward erosion).

Flat areas on the sides of a river valley, and elevated above present-day floodplain level. Terraces are formed when renewed downcutting carves through a former floodplain.

Ribonucleic acid. A single-stranded nucleic acid that acts as to transfer genetic information in the production of proteins

Rock affected by glacial erosion that has a smooth upstream side due to abrasion and a rugged downstream side due to plucking

A naturally occurring mixture of minerals, and in some cases other solid materials, that occurs in the Geosphere

The process by which igneous, sedimentary, and metamorphic rocks arise through cycling of material through the Earth's outer layers

The rock composed mainly of the mineral halite NaCl

An ancient supercontinent preceding Pangaea. Rodinia existed during the Proterozoic Eon.

Rotating movement of particles along the bed of a river.

Large-scale undulations of the polar front and the jet stream

The movement of a rock mass down slope along a curved failure surface.

The change of a system towards an extreme position relative to its starting state, as a result the amplification of an initial change by positive feedback

The extent of a flow beyond the slope on which it originated

A slipped region of a fault surface

Seismic body waves in which the vibration direction is at 90° to the propagation (travel) direction

Containing a high concentration of dissolved salts

The concentration of dissolved salts in water.

Upwarped regions in the crust produced by rising columns of rock salt and other evaporite rocks

A flow of salt that emerges onto the Earth’s surface and then flows slowly down slope

The movement of particles in water as part of bed load, with a jumping motion. Particles are pulled briefly upward out of the bed by pressure effects, and carried downstream as they fall back to the bed.

Clastic sediment with a grain-size finer than 2 mm but coarser than 1/16 mm

Clastic sedimentary rock formed from lithified sand (sediment with grains finer than 2 mm, but coarser than 1/16 mm)

A suspension of sand in the troposphere by powerful winds.

A crystal form of gypsum with long fibres.

The maximum or equilibrium amount of a substance that can be held in another. Saturated solutions contain the maximum amount of dissolved material that is in equilibrium with adjacent solid. The saturated zone of groundwater has porosity entirely filled with liquid.

The groundwater zone where pore spaces are entirely filled by water.

The maximum concentration of water vapour in air when at equilibrium with liquid water or solid ice.

The sixth planet from the Sun; a Jovian planet noted for its visible ring system

A metamorphic rock with a strong fabric (foliation) usually due to oriented, sheet-like grains of mica.

A theory or part of a theory that has withstood repeated testing and can be succinctly stated in words or as a mathematical equation.

Porous, highly vesicular rock derived from lava; may form on the surface of a lava flow, or during its pyroclastic disruption.

Fallen rock material that accumulates at the base of a steep slope.

Wind that blows from sea to land, typically during the day, caused when low pressure develops because of heating of the land by the sun. Cooler air from the sea replaces rising air over land.

Ice that has formed on the sea surface by freezing of seawater

the proportion of the ocean covered in ice at a given time.

Upstanding masses of rock isolated from adjacent sea cliffs by erosion.

A layer, or bed, of coal

Porosity formed by solution, at some time after deposition of the rock

Material derived ultimately from weathering, that is transported and/or deposited as grains on the surface of the Geosphere

The transportation of mixed sediment and water down slope through gravity.

Relating to sediment, material derived ultimately from weathering, that is transported and/or deposited as grains on the surface of the Geosphere

Rock deposited on the surface of the Geosphere by the action of the Atmosphere, Hydrosphere or Biosphere, formed from the products of the weathering and erosion of older rock

Areas on the surface of the Geosphere where petroleum (oil or natural gas) escapes.

Relating to earthquakes.

The behaviour of seismic waves that encounter a boundary within the Earth, causing some of the energy to return away from the boundary on the same side as their source

Disturbances generated by a natural earthquake or by artificial means, that propagate as vibrations through the Geosphere and over its surface.

A device used to create a record of shaking resulting from an earthquake

Physicists who study earthquakes and the propagation of waves through the solid Earth

A device used to measure shaking resulting from an earthquake

The action of environmental conditions in causing natural selection by favouring the survival of certain variants of a species over others.

A crystal form of gypsum that is transparent and colourless.

An area on the Earth's surface where seismic body waves from an earthquake are blocked by the Core

Mudstone that is fissile (ie with clay minerals aligned due to compaction causing it to break into thin flakes.

Natural gas is trapped within fine-grained sedimentary rock.

The component of stress that acts parallel to a given surface within the Earth.

Force per unit area acting parallel to a surface

Narrow zones of intense deformation accommodating movement between more rigid blocks of rock.

Silicates whose crystal structure contains sheets in which three oxygen atoms are shared between silicate tetrahedra.

The cracking of previously buried rocks into sheets as they are brought close to Earth’s surface

Gently-sloping volcanoes formed by mafic lava flows that travel over long distances.

Areas of cratons (stable continental crust) where Archean or Proterozoic metamorphic and igneous rocks are exposed.

Silicon dioxide SiO₂

A substance containing covalently bonded silicon and oxygen groups in its atomic structure

Naturally occurring crystalline solids whose composition includes groups of silicon and oxygen atoms, typically in a covalently bonded tetrahedral arrangement

Silicate Tetrahedron (Also silica tetrahedron or SiO₄ tetrahedron; plural tetrahedra): A group of four oxygen atoms covalently bonded to a silicon atom; the basic building block of silicate minerals.

Substances with silicon–oxygen groups in their atomic structure

Deep-sea deposits of fine grained sedimentary opal derived from organisms with silica skeletons such as diatoms and Radiolaria.

Sheet-like igneous intrusions are concordant with layers in their host rock

Mud particles with diameters between 1/16 mm and 1/256 mm (or 4 μm)

Fault motion such that the far wall of a fault appears displaced to the observer's left

A deep depression in the land surface

Reservoirs in a system where the residence time is so long that it effectively remove material from a cycle

Having a large number of bends (e.g. of a river channel)

One of the driving forces of plate tectonics; the force produced by high-density metamorphic rocks in a subducted slab of oceanic lithosphere.

A low-grade metamorphic rock with fine grain size and fabric (cleavage) that typically causes the rock to split into thin flakes or sheets

The movement of particles along the bed of a river without rotation.

Mass downslope of coherent material along a basal failure surface

The relative movement of blocks on either side of a fault

The deviation of a surface from horizontal; may be measured as an angle or as a tangent (rise or fall divided by horizontal "run").

A valley with exceedingly steep sides, created when a channel downcuts through strong rocks.

The flows of carbon through inorganic processes within the Geosphere, with residence times measured in millions of years

Slides in which the moving mass is significantly deformed; transitional into flows.

Ice crystals formed by condensation directly from water vapour, that fall as precipitation

A climate state in which a majority of the Earth's surface is covered with snow or ice. Snowball Earth conditions are believed to have occurred during several intervals in the Proterozoic Eon.

The level on a glacier, or more generally on any sloping land surface, above which snow persists year-round

A mixture of weathered, fragmented rock and organic matter at the surface of the Geosphere

The rate of energy input from the Sun that could theoretically be received by a unit area of the Earth’s surface.

Changes in the energy output of the sun which may affect Earth’s climate.

The Sun and all of the natural objects (including planets, their natural satellites, dwarf planets, comets, asteroids and meteoroids) in its orbit.

Matter (plasma specifically) released from the surface of the Sun that carries small amounts of energy throughout the solar system.

A mineral or mineral group in which two (or more) different elements may be present in a continuous range of proportions.

A boundary on a phase diagram separating fully solid material from material with some liquid; the start of melting.

Creep observed when groundwater freezes and thaws, allowing sediment grains to move down the slide at an annual rate.

Rounded bodies of soil or sediment formed by creep of the active layer when it is saturated and lies on a slope.

Two times in an Earth year at which one of the poles is directly tilted towards the Sun.

Attachment of dissolved material to the surfaces of solids such as clay minerals

The process in sedimentation wherein particles are separated on the basis of size, or the degree to which the particles in a sediment have been sorted, producing a narrow range of sizes.

A two-stage climate pattern operating over periods of several years in which water in the central and easter Pacific Ocean is alternately warmer and colder than average, impacting the flow of water in the Pacific and global weather patterns

The smallest conventional taxonomic group; typically defined as a group of organisms capable of reproducing and producing with viable offspring that can also reproduce. Species are grouped into genera.

A black variety of hematite with a highly reflective metallic lustre

A mineral oxide of magnesium and aluminum; also, a mineral group of similar structure in which different metallic ions are present (eg Fe, Mn, Cr).

Peninsulas of beach sediment extending away from the shore into the sea:

A depositional landform formed by longshore drift of sediment.

Primitive multicellular animals that lack true tissues and organs; most are filter-feeders

A plate boundary where plates are moving apart, away from the boundary

Natural points of groundwater discharge that occur when the water table or a permeability boundary intersects the land surface.

A tidal phenomenon caused by the alignment of the Moon, Sun, and Earth along a single line, producing a maximum tidal range and accentuating tidal effects.

A state wherein a compound is unlikely to undergo a phase change or chemical reaction.

An isotope that is able to persist over long periods of time without decay

A narrow cone of dripstone hanging from the roof of a cave or other cavity

Dripstone formations that taper downward from the ceilings of caves.

A pillar of dripstone formed on the floor of a cave or other cavity

Dripstone formations that rise upward from the floor of caves.

A complex carbohydrate polymer used by plants to store energy.

A system without a net flux of materials in or out; a steady state describes a system that remains unchanging over time.

Openings on plant leaves that allow plants to exchange gases with their surroundings

A phase in human history when tools were made primarily from rock materials

Local rise in sea level along a coast beneath a major storm due to the combined effect of onshore wind and reduced air pressure

A change in shape or volume

A description of sedimentary layers in the form of a columnar diagram, with the oldest layers at the bottom and the youngest at the top

Low altitude clouds that are generally horizontally extensive, like stratus, though displaying domed or clumped features resembling cumulus

The boundary dividing the mesosphere and stratosphere in Earth’s atmosphere. Here, the temperature reaches its peak between the two layers.

A zone of upward-increasing temperature in the atmosphere, between the tropopause, below, and the stratopause, above.

Conical volcanoes consisting of alternating layers of lava and tephra, typical of intermediate magma compositions.

Stratum (plural strata): a layer of rock, typically sedimentary

Clouds that form horizontal, flat layers at low altitudes. Typical of warm fronts.

The colour of mineral when finely powdered

.

An unglazed tile used to obtain a streak colour by abrading the mineral against its surface

The movement of water through confined channels over Earth’s surface.

The force per unit area exerted on a plane, or the combination of all such forces exerted at a point within a solid.

Grooves carved in bedrock as a result of glacier movement

Near-horizontal movement between two blocks separated by a fault.

Finely layered (laminated) mounds or pillars of calcium carbonate deposited by cyanobacteria

The plate tectonic process whereby one plate descends beneath another as plates converge

A convergent plate boundary where one plate descends beneath another.

Formed below a glacier

A lake hidden below glacier ice

The phase change of solid directly to gas, without liquid as an intermediary step.

Steeply descending valleys in the sea-floor, typical of the continental slope.

Seafloor sediment bodies typically formed at the downslope end of submarine canyons. Sediment is distributed by turbidity currents over an area that is often roughly semi-circular.

An element or ion in a crystal lattice that replaces another, typically of similar size and electron configuration

A phenomenon where by an element or ion in a crystal lattice is replaced by a different element

Negative ions consisting of sulfur and oxygen: SO₄²⁻

Minerals containing oxidized sulfur in the form of sulfate ions with the formula SO₄²⁻

Minerals containing negative ions of reduced sulfur.

A dimmer patch on the photosphere of the Sun associated with magnetic storms

The 11 year-long rise and fall in sunspot activity across the surface of the Sun, associated with a minor change in irradiance

A large conglomeration of continental lithosphere, typically including the majority of continental crust on Earth at a given time.

High pressure fluid that combines properties of a liquid and a gas

The coastal area in which wave crests move faster than deeper water inhibited by drag against the seafloor. As a result, turbulence occurs as waves break over one another.

Ocean currents at the top of the top of the water column, caused by wind and tides, additionally deflected by the Coriolis effect.

A feature of liquid surfaces that tends to reduce the area of surface.

Seismic waves that travel along the surface of the Geosphere

The process whereby particles remain above the bed of a body of water, because they are carried upward by fluid turbulence at a rate faster than their speed of settling.

Fine-grained sediments that may be suspended within turbulent waters.

The evolutionary process whereby eukaryotic organisms developed from prokaryotic ancestors: one prokaryote evolved to enclose another in a mutually supportive relationship chloroplasts and mitochondria developed through symbiogenesis.

A close association between two organisms, whereby both gain benefits from the relationship

A portion of the universe that can be regarded as separate from its surroundings for some scientific purpose.

Scree; fallen rock materail accumulated at the base of a cliff or other steep slope

The categories and methods used by biologists to classify living organisms

Relating to movements of the Earth's lithosphere

A measure of the average kinetic energy of the atoms or molecules in a material, typically measured on the Celsius (°C) or Kelvin (K) scale

Rock fragments generated by volcanic eruptions

A body of till marking the furthest extent of a glacier’s ice.

The lower limit of a glacier

Associated with the Earth

The four innermost planets of the solar system believed to have iron-rich cores surrounded by rocky mantles, without the thick atmospheres characteristic of the outer planets.

Sediment originating from land.

The sizes, shapes, and relationships between the mineral grains that make up a rock.

A hypothesis, or group of hypotheses, that has survived many experimental or observational tests, leading to general acceptance of its explanatory power

The depth zone within the ocean’s where the greatest rate of downward temperature decrease is observed.

The movement of water currents throughout the oceans as a consequence of differemces om temperature and salinity

Deep ocean currents driven by differences in temperature and salinity.

The layer of the Atmosphere above the Mesopause, where temperature increases with elevation.

A gently sloping fault where the hanging wall has moved up the slope of the fault over the footwall.

A severe weather system with rain and/or hail together with electrical discharges (lightning) that cause thunder

The vertical distance between high and low tide levels at a point on the Earth's surface.

The change in Earth’s surface elevation (particularly water surfaces) due to changes in the gravitational pull of the Moon and Sun.

A glacier that enters marine water at its terminus

Unsorted sediments deposited directly from glacier ice

Lithified till: Unsorted sediments deposited directly from glacier ice, subsequently solidified

The variation in elevation from place to place on the surface of the Geosphere, on land. (The corresponding measurement of the seafloor is bathymetry.)

A narrow and intense spiral updraft that commonly develops from a funnel cloud, and features very low pressure at its centre.

Describes a substance that inhibits the growth, reproduction, or survival of an organism

a substance that inhibits the growth, reproduction, or survival of an organism

Structures in rocks that preserve evidence of past organisms’ movement or other activity; also known as ichnofossils.

Force per unit area; also known as stress

Persistent east-to-west winds in the tropics that were used for trade by sailing ships. The term "tropical easterlies" is preferred in this text.

Describes tectonic motion that is mostly horizontal and parallel to a tectonic boundary

A plate boundary where relative plate motion is parallel to the boundary.

The movement of a rock mass down slope along a planar failure surface.

The transfer of liquid water to water vapour in the atmosphere at plant surfaces.

Cylindrical structures developed in the woody stems of trees, typically one per year

Deep troughs on the ocean floor where oceanic lithosphere is subducted at a convergent plate boundary

Smaller streams that flow and converge downstream into a larger channel.

A point in a phase diagram where a substance (such as water) can remain in equilibrium in the liquid, gas, and solid states simultaneously.

A cyclonic storm that develops north or south of the intertropical convergence zone. A storm must achieve a windspeed >120 km/hr to be considered a tropical cyclone.

Persistent east-to-west winds that flow in the tropics

A cyclonic storm with a wind speed less than >120 km/hr that nevertheless forms from warm moist air north or south of the intertropical convergence zone

The boundary lying between the troposphere and the stratosphere, where temperatures reach a minimum after decreasing with altitude in the troposphere, and before increasing once again in the stratosphere.

The lowest part of Earth’s atmosphere directly in contact with the surface of the Earth, which warms it from below, leading to an upward decrease in temperature. The troposphere contacts the stratosphere at the tropopause.

A wave on the ocean surface resulting from an earthquake, volcanic eruption or a landslide.

Solid pyroclastic rock formed from lithified tephra.

Cloudy water caused by suspended load.

A turbulent flow of sediment-rich water moving down slope under clearer water due to the action of gravity.

Swirling movements in a fluid that developed due to the velocity of a current.

Having turbulence: wirling movements in a fluid.

Fluid movement where swirling and mixing within the fluid allows sediment suspension.

A plane within a crystal across which the crystal lattice adopts a reflected or rotated orientation

A tropical cyclone in the North Indian Ocean or West Pacific

Magma or igneous rock with a silica content of less than 45%

Electromagnetic radiation with wavelength slightly shorter than visible light, and frequency slightly higher, lying beyond violet in the electromagnetic spectrum.

An aquifer where the upper boundary is the water table

An ancient erosion surface where younger sediment was deposited on eroded older rock

Unconventional hydrocarbons are those contained in low-permeability rocks, that do not flow out of the rocks without intervention

consisting of a single biological cell

The principle that processes that operated in the Earth's past can all be explained by processes that continue to operate at the present day. Strict application of uniformitarianism in Earth science has largely been replaced by actualism

An isotope whose nucleus undergoes randomly decay.

Rise of deeper water to the surface, typically due to Ekman transport that forces water away from a coasts.

The seventh planet from the Sun. Uranus is a Jovian planet with a rotational axis with obliquity of nearly 90°

Universal transverse Mercator

In groundwater study, the zone above the water table where pore spaces are partly filled by water. (Also known as the aerated zone.)

An elongated glacier formed as ice from higher elevations flows between exposed rocky slopes.

The rise of warm air up mountain sides during the day

Alternating layers deposited in lakes, representing annual glacial melt events.

A fracture that has been has been a site for formation of minerals

Cracks in rock that have been filled by minerals.

A measure rate of motion that includes both speed and direction.

The rate of change (with distance) of velocity in a fluid such as water

Pipe-like channels up which magma may flow.

The third planet from the Sun known for its similar size to Earth; the brightest planet in Earth's night sky

Rounded cavities in igneous rock formed by gas bubbles in the magma.

The hypothesis that symmetrical patterns of linear magnetic anomalies on the ocean-floor have been produced by ocean-floor spreading combined with reversals of the Earth's magnetic field.

A particle usually consisting of nucleic acid wrapped in protein that can reproduce when it invades a host organism and takes over some of the host's living processes to achieve reproduction

A measure of the resistance of a fluid to shearing; measured as the force concentration needed to achieve a given velocity gradient. In everyday terms, a measure of hhow 'thick' a fluid is.

Describes liquids with high ability to resist flow

The behaviour of liquids (or solids near their melting point) in which the material deforms at a rate proportional to the applied stress.

Vitreaous (glassy) lustre: Describes the image-forming reflection of light from the surfaces of a mineral that also has some transparency.

Dissolved water and gas in magma, or the behaviour of such material

Relating to volcanoes: places where magma reaches the surface of the Geosphere as lava

A chain of volcanoes that lies above a downgoing slab of lithosphere at a subduction zone

Fine-grained tephra less than 2 mm in diameter.

Volcanic fragments larger than 64 mm in diameter that are released in explosive eruptions.

Igneous rock formed by rapid cooling of lava, such that crystal lattices are unable to form; rock with the structure of a supercooled liquid.

Metal sulphide deposits formed typically where hydrothermal vents allow hot water to deposit metal-bearing sulfide minerals within and upon ocean floor.

A type of mineral deposit formed by hydrothermal fluids flowing through igneous rock, typically rich in copper and other elements

Places where magma reaches the Geosphere surface.

A sloping zone of deep earthquakes associated with a convergent plate boundary

A boundary between air masses where warm air advances towards and over cold air

Glacial ice that is close to freezing point, and has liquid water at base.

A compound critical for life on Earth, consisting of two hydrogen atoms and one oxygen: H2O.

The continuous transport of water between the various spheres of the Earth through a series of reservoirs

The divide between the saturated and vadose zones of groundwater.

Water in its gaseous state, a colourless invisible gas

A synonym for drainage basin, in North America. In UK English, the drainage divide between two drainage basins

The circular or elliptical motion of particles beneath a wave

The maximum depth below the water surface at which sediment is affected by motion from waves.

The distance between the two successive maximum values or crests in any wave-like phenomenon.

Short-term changes in Earth’s atmosphere

The breakdown of rock material at the Geosphere surface due to the action of the Atmospher, Biosphere, and or Hydrosphere.

Sedimentary deposits with particles of about the same size.

Winds that blow from west to east, most typically at mid-latitudes, where they are driven by a combination of pressure-gradient flow and the Coriolis effect

world geodetic system 1984

Fragments of host rocks that are embedded within an igneous intrusion.

The year 1816 CE; a short-term cooling in climate occurred during the growing seasons of the Northern Hemisphere, possibly due to the long-term effects of a volcanic eruption of Mount Tambora, Indonesia