Glossary Starting with the letter: C


See Carbon Dioxide

Calcium Carbonate

(CaCO3) A colorless or white crystalline compound occurring naturally as the minerals calcite or aragonite in rocks like chalk, limestone, and marble.

Carbon Cycle

The combined processes by which carbon as a component of various compounds cycles between its major reservoirs: the atmosphere, oceans, living organisms, and solid Earth. The processes include photosynthesis, decomposition, respiration, sedimentation, lithification, burial, uplift, erosion, and volcanism.

Carbon Dioxide

(CO2) An odorless, colorless, incombustible gas that is 1.5 times as dense as air and is formed during respiration, combustion, and organic decomposition. It is one of the principle greenhouse gases in Earth’s atmosphere (after water vapor).

Carbon Monoxide

(CO) A colorless, almost odorless, poisonous, and flammable gas. It is a pollutant formed by the incomplete combustion of carbon-containing fuel.

Carbon-14 Dating

A method of determining the approximate age in years of a carbon-bearing object by measuring the decay of radioactive carbon-14.


Any mineral compound that contains the anion (negatively charged molecule) CO3-2.

Carbonate Sedimentation

A process by which carbonate sediment is deposited.

Carbonic Acid

(H2CO3) A weak acid resulting from the solution of carbon dioxide in rain or groundwater.


The concept that major features in the Earth’s crust such as mountains, valleys and oceans, have been produced by a few great catastrophic events, such as the Great Flood.

Chemical Equilibrium

The state in which forward and reverse chemical reactions occur at equal rates so that the concentration of the reactants and products does not change with time.

Chemical Weathering

The process of breaking down rocks or minerals at or near the Earth’s surface by chemical processes, including hydrolysis, hydration, ion exchange, and oxidation.


Synthetic chemical compounds used in refrigeration, solvents, and styrofoam manufacture. These compounds break down in the upper atmosphere and release chlorine atoms which destroy ozone.


A group of green, light-collecting pigments found in green plants, algae, and some bacteria that in the presence of sunlight convert CO2and H2O into carbohydrates.


Average weather conditions of a region, including temperature, precipitation, and winds.

Climate Change

a change in global or regional climate patterns, in particular a change apparent from the mid to late 20th century onwards and attributed largely to the increased levels of atmospheric carbon dioxide produced by the use of fossil fuels.


The scientific study of climate.


Any rock fragment larger than a pebble and smaller than a boulder, especially one that has been naturally rounded.

Continental Crust

The part of the Earth’s crust that comprises the continents and is typically ~45 km thick. Together with the oceanic crust it makes up the outermost shell of the solid Earth.

Continental Drift

slow, lateral movements of continents across the surface of the Earth.


The process by which hot, less dense material rises upward and is replaced by cold, more dense, downward-flowing material.

Convection Cells

The currents that are set up by convection.


The spherical mass, largely of metallic iron and nickel, at the center of the Earth. The outer core extends from 2,900 kilometers to 5,100 kilometers from Earth’s surface and is molten. The inner core, from 5,100 kilometers to the center of Earth at 6,400 kilometers, is solid.

Core-mantle Boundary

The separation between the liquid metal of the outer core and the solid rock of the lower mantle (also called the Gutenberg Discontinuity).

Coriolis Force

An affect that causes any body that moves freely with respect to the solid Earth to veer to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.

Cosmic Radiation

High-energy, subatomic particles from outer space, which bombard Earth’s atmosphere. Most cosmic radiation is absorbed in Earth’s upper atmosphere.

Country Rock

The older, preexisting rock that encloses or is traversed by an igneous intrusion or a mineral deposit.


A deep, almost vertical, crack or split in the upper part of a glacier.


Layers that are inclined with respect to a thicker layer within which they occur.


The outermost and thinnest of the solid Earth’s layers, which consists of rocky material that is less dense than the rocks of the mantle below.

Crustal Thickening

The thickening of the continental crust when two continents collide to create mountains.


A cryosphere contains the frozen parts of a planet. It includes snow and ice on land, ice caps, glaciers, permafrost, and sea ice. This sphere helps maintain the plantes climate by reflecting incoming solar radiation back into space.


Microscopic organisms that grow within rocks.


Any homogeneous solid with a regularly repeating atomic arrangement that may be expressed by plane faces; and a characteristic composition.

Crystal Fractionation

The separation of crystals of one composition from magma of another composition, thus causing the residual magma to change composisiton.