How can we help?

You can also find more resources in our Help Center.

126 terms

GeoPhysical Vocabulary

STUDY
PLAY
geology
study of the earth
meteorology
study of the atmosphere and the processes that produce weather and climate
astronomy
study of the universe
latitude
distance north and south of the equator
longitude
distance east or west of the prime meridian
topographic map
show elevation of Earth's surface by means of contour lines
hypothesis
a tentative explanation that is tested to determine if it is valid
anticyclone
a high-pressure center characterized by a clockwise flow of air in the Northern Hemisphere
aphelion
the place in the orbit of a planet where the planet is farthest from the sun
apogee
the point where the moon is farthest from the Earth
apparent magnitude
the brightness of a star when viewed from Earth
aquifer
rock or soil throuugh which groundwater moves easily
astronomical unit (AU)
average distance from Earth to the sun
atmosphere
the gaseous portion of a planet; the planet's envelope of air;
aqueduct
a pipe or channel through which water flows from a higher elevation to a lower elevation
aurora
a bright display of ever changing light caused by solar radiation interacting with the upper atmosphere in the region of the poles
barometer
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
biosphere
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
caldera
a large depression typically caused by collapse or ejection of the summit area of a volcano
cementation
solidification of sediments by the deposition of dissolved minerals in the tiny spaces between the sedimentary particles
chromosphere
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
cleavage
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
comet
a small body made of rocky and metallic pieces held together by frozen gases
compaction
process by which sediments are squeezed together by the weight of overlying materials driven out by water
condensation
the change of state from a gas to a liquid
conduction
the transfer of heat through matter by molecular activity; Energy is transferred through collisions from one molecule to another
conservation
the careful use of resources
constellation
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
convection
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
core
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
Corona
the outer weak layer of the solar atmosphere
crater
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
crust
the thin, outer layer of Earth
crystal form
the external appearance of a mineral as determined by its internal arrangement of atoms
cyclone
a low-pressure center characterized by a counter-clockwise flow of air in the Northern Hemisphere
deformation
general term for the processes of folding, faulting, shearing, compression, or extension of rocks as the result of various natural forces
density
mass per unit volume of a substance, usually expressed as grams per cubic centimeter
deposition
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
earthquake
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
ellipse
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
epicenter
the location on Earth's surface directly above the focus, or origin, of an earthquake
erosion
the incorporation and transportation of material by a mobile agent, such as water, wind, or ice
evaporation
the process of converting a liquid to a gas
extrusive igneous rock
igneous rock that has formed on Earth's surface
fault
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
flood
occurs when the discharge of a stream becomes so great that it exceeds the carrying capacity of its channel and overflows its banks
focus
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
foreshock
a small earthquake that often proceeds a major earthquake
fossil
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
fracture
any break or rupture in rock along which no appreciable movement has taken place
front
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
galaxy
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
geocentric
describes the concept of an Earth-centered universe
geology
the science that examines the Earth, its form and composition, and the changes it has undergone and is undergoing
geosphere
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
gradient
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
groundwater
water underground in the zone of saturation
hardness
the resistance a mineral offers to scratching
heliocentric
describes the view that the sun is at the center of the solar system
heat
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
humidity
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
hurricane
a tropical cyclonic storm having winds in excess of 119km per hour
hydrogenous sediment
seafloor sediment consisting of minerals that crystallize from seawater
hydrosphere
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
hypothesis
a tentative explanation that is tested to determine if it is valid
igneous rock
a rock formed by the crystallization of molten magma
infiltration
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
laccolith
a massive igneous body intruded between preexisting strata
latitude
the distance north or south of the equator, measured in degrees
lava
magma that reaches Earth's surface
light-year
the distance light travels in a year, about 9.5 trillion km
liquefaction
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
lithosphere
the rigid outer layer of earth, including the crust and upper mantle
longitude
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
luster
the appearance or quality of light reflected from the surface of a mineral
magma
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
mantle
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