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study of the earth


study of the atmosphere and the processes that produce weather and climate


study of the universe


distance north and south of the equator


distance east or west of the prime meridian

topographic map

show elevation of Earth's surface by means of contour lines


a tentative explanation that is tested to determine if it is valid


a high-pressure center characterized by a clockwise flow of air in the Northern Hemisphere


the place in the orbit of a planet where the planet is farthest from the sun


the point where the moon is farthest from the Earth

apparent magnitude

the brightness of a star when viewed from Earth


rock or soil throuugh which groundwater moves easily

astronomical unit (AU)

average distance from Earth to the sun


the gaseous portion of a planet; the planet's envelope of air;


a pipe or channel through which water flows from a higher elevation to a lower elevation


a bright display of ever changing light caused by solar radiation interacting with the upper atmosphere in the region of the poles


instrument that measures atmospheric pressure

big bang theory

the theory that proposes that the universe originated as a single mass, which subsequently exploded

binary star

one of two stars revolving around a common center of mass under their mutual gravitational attraction


all life on Earth; the parts of the solid Earth, hydrosphere and atmosphere that living organisms can be found

black hole

massive star that has collapsed to such a small volume that its gravity prevents the escape of everything, including light


a large depression typically caused by collapse or ejection of the summit area of a volcano


solidification of sediments by the deposition of dissolved minerals in the tiny spaces between the sedimentary particles


the first layer of the solar atmosphere found directly aove the photosphere

cinder cone

a small volcano built primarily of pyroclastic material ejected from a singl vent


tendency of a mineral to break along planes of weak bonding

cold front

a front along which a cold air mass thrusts beneath a warmer air mass


a small body made of rocky and metallic pieces held together by frozen gases


process by which sediments are squeezed together by the weight of overlying materials driven out by water


the change of state from a gas to a liquid


the transfer of heat through matter by molecular activity; Energy is transferred through collisions from one molecule to another


the careful use of resources


an apparent group of stars originally named for mythical characters

contact metamorphism

changes in rock caused by the heat from a nearby magma body

continental drift

a hypothesis that originally proposed that the continents had once been joined to form a single supercontinent; the supercontinent broke into several pieces, which drifted to their present day positions

continuous spectrum

an uninterrupted band of light emitted by an incandescent solid, liquid or gas under pressure


the transfer of heat by the movement of a mass or substance; it can take place only in fluids

convergent boundary

a boundary in which two plates move together


the innermost layer of Earth, located beneath the mantle

Coriolis Effect

the apparet deflective force of Earth's rotation on all free-moving objects, including the atmosphere and oceans; Deflection is to the right in the Northern Hemisphere and to the left in the Southern Hemisphere


the outer weak layer of the solar atmosphere


the depression at the summit of a volcano or that which is produced by a meteorite impact

cross-cutting relationships, principle of

principle of relative dating; a rock or fault is younger than any rock or fault through which it cuts


the thin, outer layer of Earth

crystal form

the external appearance of a mineral as determined by its internal arrangement of atoms


a low-pressure center characterized by a counter-clockwise flow of air in the Northern Hemisphere


general term for the processes of folding, faulting, shearing, compression, or extension of rocks as the result of various natural forces


mass per unit volume of a substance, usually expressed as grams per cubic centimeter


the process by which an agent of erosion loses energy and drops the sediment it is carrying;

divergent boundary

a region where the rigid plates are moving apart, typified by the oceanic ridges

Doppler effect

the apparent change in frequency of electromagnetic or sound waves caused by the relative motions of the source and the observer


the vibration of Earth produced by the rapid release of energy

elastic rebound hypothesis

the explanation stating that when rocks are deformed, they break, releasing the stored energy that results in the vibrations of an earthquake

contour lines

lines on a topographic map that indicates an elevation

contour interval

on a topographic map, tells the distance in elevation between adjacent contour lines

Earth Science

the name for all the sciences that collectively seek to understand Earth; it includes geology, oceanography, meteorology,

electromagnetic spectrum

the arrangement of electromagnetic radiation according to wavelength


an oval

El Nino

the name given to the periodic warming of the ocean that occurs in the central and eastern Pacific

emission spectrum

a series of bright lines of particular wavelengths produced by a hot gas under low pressure


the location on Earth's surface directly above the focus, or origin, of an earthquake


the incorporation and transportation of material by a mobile agent, such as water, wind, or ice


the process of converting a liquid to a gas

extrusive igneous rock

igneous rock that has formed on Earth's surface


a fracture in Earth along which movement has occurred

fault-block mountain

a mountain formed when large blocks of crust are tilted, uplifted or dropped between large normal faults


occurs when the discharge of a stream becomes so great that it exceeds the carrying capacity of its channel and overflows its banks


the point within Earth where an earthquake originates

folded mountain

a mountain created primarily by compressional stresses, which create folds in the rock layers

foliated metamorphic rock

a metamorphic rock with a texture that gives the rock a layered appearance


a small earthquake that often proceeds a major earthquake


the remains or traces of an organism preserved from the geologic past

fossil fuel

general term for any hydrocarbon that may be used as a fuel, including coal, oil, and natural gas


any break or rupture in rock along which no appreciable movement has taken place


the boundary between two adjoining air masses having contrasting characteristics

frost wedging

the mechanical breakup of rock caused by the expansion of freezing water in cracks and crevices


a group of stars, dust, and gases held together by gravity

galaxy cluster

a system of galaxies containing from several to thousands of member galaxies


describes the concept of an Earth-centered universe


the science that examines the Earth, its form and composition, and the changes it has undergone and is undergoing


layer of Earth under both the atmosphere and the oceans; composed of the core, mantle and crust

geothermal energy

energy that can be extracted from Earth's internal heat, for example, natural steam used for power generation

geothermal field

an area of land where magma lies relatively close to the surface and heats the groundwater

geothermal gradient

the gradual increase in temperature with depth in the crust

global warming

the increase in average temperatures of Earth and the atmosphere due in part to increase carbon dioxide levels


the slope of a stream over a certain distance

granitic composition

a compositional group of igneous rocks that indicate a rock is composed almost entirely of light-colored silicates, mainly quartz and feldspar

greenhouse effect

the heating of Earth's surface and atmosphere from solar radiation being absorbed and emitted by the atmosphere, mainly by water vapor and carbon dioxide


water underground in the zone of saturation


the resistance a mineral offers to scratching


describes the view that the sun is at the center of the solar system


thermal energy transferred from one object to another

hot spot

a concentration of heat in the mantle capable of producing magma, which rises to Earth's surface; The Pacific Plate moves over a hot spot, producing the Hawaiian Islands

H-R Diagram

a plot of stars according to their absolute magnitudes and temperatures

Hubble's Law

a law that states that the galaxies are retreating from the Milky Way at a speed that is proportional to their distance


a general term referring to water vapor in the air but not to liquid droplets of fog, cloud, or rain

humid subtropical climate

a climate generally located on the eastern side of a continent and characterized by hot, sultry summers and cool winters


a tropical cyclonic storm having winds in excess of 119km per hour

hydrogenous sediment

seafloor sediment consisting of minerals that crystallize from seawater


the water portion of Earth; one of the traditional subdivisions of Earth's physical environment

hydrothermal solution

the hot, watery solution that escapes from a mass of magma during the later stages of crystallization; such solutions may alter the surrounding rock


a tentative explanation that is tested to determine if it is valid

igneous rock

a rock formed by the crystallization of molten magma


the movement of surface water into rock or soil through cracks or pore spaces

inner core

the solid innermost layer of Earth

intertidal zone

the area where land and sea meet and overlap; the zone between high and low tides

intraplate volcanism

igneous activity that occurs within a tectonic plate away from plate boundaries

intrusive igneous rock

igneous rock formed below Earth's surface

jet stream

swift, high altitude winds

Jovian planet

the Jupiter like planets; Jupiter, Saturn, Uranus, and Neptune. These planets have relatively low densities and are huge gas giants

Koppen Classification System

a system for classifying climates based on mean monthly and annual values of temperature and precipitation


a massive igneous body intruded between preexisting strata


the distance north or south of the equator, measured in degrees


magma that reaches Earth's surface


the distance light travels in a year, about 9.5 trillion km


a phenomenon, sometimes associated with earthquakes, in which soils and other unconsolidated materials saturated with water are turned into a liquid that is not able to support buildings


the rigid outer layer of earth, including the crust and upper mantle


the distance east or west of the prime meridian, measured in degrees

lunar eclipse

an eclipse of the moon; occurs when the moon passes through Earth's shadow

lunar regolith

a thin. gray layer on the surface of the moon, consisting of loosely compacted, fragmented material believed to have formed by repeated impacts of meteorites


the appearance or quality of light reflected from the surface of a mineral


a body of molten rock found at depth, including any dissolved gases and crystals

main-sequence star

a star that falls into the main sequence category on the H-R diagram; this category contains the majority of stars and runs diagonally from the upper left to the lower right on the H-R diagram


layer of Earth located below the crust

mass movement

the downslope movement of rock, regolith and soil under the direct influence of gravity

mechanical weathering

the physical disintegration of rock, resulting in smaller fragments

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