Note to students: If you are looking here for your vocabulary homework, you still need to write the definitions in your own words.

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abrasion: when two rocks scratch each other by rubbing against each other.

absolute time: measuring the time of an event using a number on the time line.

absolute zero: the coldest that any matter can be. It is -273º Celsius.

adiabatic cooling: air cooling as it rises due to expansion and spreading the heat out.

adiabatic heating: the heating of air caused by pressurization which concentrates the heat.

adiabatic lapse rate: the rate at which dry air cools as you go up in altitude.

agent of erosion: anything that pushes sediment from one location to another.

air pressure: weight of the air above you.

albedo: a ratio between the amount of sunlight that comes in as compared to the amount of sunlight that is reflected.

Alberta clipper: a strong but fast moving low pressure system.

alpine glacier: a “river of ice” that flows down through mountain valleys.

angle of insolation: the angle at which sunlight strikes the ground.

anticyclone: high pressure system with an outward and clockwise air flow.

apparent motion: the way an object in space appears to move caused by the motion of the Earth.

aquitard: a layer of low permeability that acts as a cap.

artesian well: a source of water where the water comes out of the ground under natural pressure.

asthenosphere: the upper mantle in which convection takes place.

atmosphere: the layer of air that surrounds the Earth.

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basal cleavage: splitting into flat sheets.

benchmark: a spot on the surface of the Earth where an exact elevation was measured.

bioclastic: “fragments of life” rock made up of broken shells.

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caldera: the wide crater at the top of a shield volcano.

capacity (humidity): the amount of water vapor that the air can hold.

capillarity: water being drawn upwards against the pull of gravity through tiny pores.

capillary fringe: a zone right on top of the water table where capillary action draws some water upwards.

cementation: process of “gluing” sediments together.

chemical weathering: breaking down of rock material by the reaction of some chemical.

Chinook: a warm dry air that descends on the leeward side of a mountain.

cinder cone: a volcanic mountain made from cinders.

cinder: small pieces of volcanic rock thrown from a volcano.

clastic: a sedimentary rock made up of bits and pieces of any other rock.

cleavage: property of a mineral causing it to split along flat surfaces.

climate: the typical type of weather that an area has.

cloud base height: altitude at which clouds will form. Air temperature and dew point temperature are equal.

cold front: the leading edge of an incoming cold air mass.

compaction: to compress under great pressure.

composite cone: volcanic mountain made from alternating lava flows and cinder eruptions.

conchoidal fracture: breaking into bold shaped depressions.

conduction: heat transfer between two materials that are touching.

cone of depression: a section of the water table that is drawn down as the water is pumped out.

contact metamorphism: a metamorphic change in rock caused by contact with extreme heat.

continental air mass: a dry air mass.

continental drift: the theory that the Earth’s land masses are slowly moving around.

continental glacier: a large ice sheet that covers entire continents.

contour interval: the amount of elevation change from one contour line to the next.

convection cell: a complete loop caused by rising and sinking air.

convection current: the movement of air caused by the density differences in hot and cold air.

convection: a heat transfer method that is caused by hot air rising and cold air sinking.

converges: air currents come together caused by the sucking action of a low pressure system.

Coriolis Effect: wind and ocean currents are deflected to their right in the Northern Hemisphere caused by the Earth’s rotation.

correlation: matching one layer of rock with another layer of rock in a distant location.

cross-beds: slanted layers of sorted sediments that are deposited in river deltas or meanders.

crust: the outer rock layer of the Earth on which we live.

crustal activity: any movement of the crust such as earthquakes, mountain building, and volcanoes.

cubic cleavage: breaking into cubes where each of the corners meet at 90 degrees.

cyclic: a pattern that repeats over and over again.

cyclone: a low pressure system that has an inward and counter clockwise air flow.

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delta: the triangular-shaped deposit at the mouth of a stream.

density: the amount of matter that is packed into each cube of space.

dew point lapse rate: the rate at which the temperature of humid air cools as you go up in elevation.

dew point: the temperature at which humidity becomes 100% and condensation forms.

direct relationship: relationship between two numbers where as one number increases, the other number also increases. Graphs of direct relationships will slant upwards to the right.

discharge: the amount of water flowing through a stream.

divergent plate boundary: place where two plates are spreading apart.

divergent: when currents of air flow away from each other caused by high pressure.

downhill creep: the movement of soil sliding downhill slowly over many years.

dynamic equilibrium: a system in which two opposite processes balance each other so that there is no overall change.

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eccentricity: a measure of how squashed an ellipse is.

elastic rebound theory: theory that says that before an earthquake, the rocks will stretch as far as they can and then suddenly snap.

ellipse: a squashed circle. The locus of points that are equidistant from two foci.

epicenter: the spot on the surface of the Earth closest to the source of the earthquake.

erosion: the transportation of sediments from one location to another.

erratic: a boulder transported by a glacier.

evaporites: sedimentary rock formed by minerals deposited after the evaporation of water.

evapotranspiration: the combination of evaporation and transpiration.

evolution: the gradual changing pattern of organisms.

exfoliation: the flaking of the outer surface of a rock.

extinction: the final ending of a species.

extrapolate: to take a set of data and extend it into the future.

extrusive: igneous rock formed on the surface of the Earth.

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fault: a crack in the Earth where the movement of an earthquake takes place.

field: a section of the Earth where a measurement can be taken at any point.

flood plain: the wide flat section of land next to a river.

foci: plural of focus.

focus (ellipse): one of the two central points of an ellipse.

focus: spot within the Earth where an earthquake begins.

foliation: a flaky or banded texture pattern in metamorphic rocks.

fossil: the preserved remains or evidence of life.

fracture: not breaking into geometric shapes.

front: the leading edge of an incoming air mass.

frost action: the breaking of rock material caused by the extreme pressure of freezing water.

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gas giant: a large planet with a low density made mainly of gas.

geocentric theory: theory that the Earth is the center of the Universe.

Geographic North Pole: a place on the Earth where the axis of rotation meets the ground.

gibbous: a phase of the moon in between half and full. Gibbous means egg-shaped.

glassy (luster): shining like a broken piece of glass also known as vitreous.

glassy (texture): a smooth texture in igneous rocks caused by very rapid cooling.

gnomonic projection: a map projection made by placing a flat piece of paper against a point on the surface of a globe.

GPS: global positioning system. It is a network of satellites that gives an exact position on the surface of the Earth.

graded bedding: layers of sorted sediments stacked on top of each other.

gradient: how quickly a value changes across a map.

great circle: a circle around the Earth that has the core of the Earth at its center.

greenhouse effect: the trapping of heat in the atmosphere by gases such as carbon dioxide.

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half-life: the amount of time that it takes for 50% of a radioactive element to decay.

hardness: a mineral’s resistance to scratching.

heliocentric theory: theory that the Sun is the center of the Universe.

horizontal sorting: sediments are sorted from side to side as water gradually slows down.

hot spot: a volcanically active spot that is not on the edge of a plate.

hurricane: a large organized storm with heavy rains and strong winds.

hydrologic cycle: see water cycle.

hydrosphere: the water portion of the Earth. It includes the oceans, lakes, ice caps and ground water.

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igneous: rock formed from the solidification of melted minerals.

index fossil: the fossil of a creature that existed for a short time, but lived over a wide area.

inference: using information to come to a conclusion or to make a prediction.

infiltration: water seeping down through soils.

interpolate: to use two data points to infer a middle value.

intrusive: rocks solidified while still inside the Earth.

inverse relationship: relationship between two numbers where as one number increases, the other number decreases. Graphs of direct relationships will slant downwards to the right.

isoline: a line connecting points of equal value.

isotope: a variety of an element with different numbers of neutrons.

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Jovian planet: a large Jupiter-like planet.

kinetic energy: the energy that comes from an object’s motion.

land breeze: wind that goes from the land to the sea during the night.

latitude: the degrees north or south of the equator. Latitude lines run side-to-side and they are all parallel to each other.

lava: melted rock material that has reached the surface of the Earth.

leeward: the side of a mountain away from the wind.

light-year: the distance light travels in a year.

lithification: process of turning into solid rock.

lithosphere: the solid rock portion of the Earth. It includes the crust and the upper mantle.

longitude: degrees east or west of the Prime Meridian.

luminosity: the amount of light that a star emits.

lunar eclipse: the moon gets darker when the Earth gets in between the Sun and the moon.

luster: the way a mineral shines or does not shine.

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magma: melted rock material that is still below the surface of the Earth.

magnetic declination: a measure of how wrong a magnetic compass will be in a certain area of the world.

Magnetic North Pole: a place in extreme northern Canada where all magnetic compasses point to.

main sequence: a typical star. Stars spend most of their lifetimes as main sequence stars.

mantle: the deeper layer inside the Earth made of partly melted rock material.

map projection: a drawing representing a section of the Earth.

marine air mass: a humid air mass formed over the water.

mass extinction: the extinction of a larger than normal number of species.

meander: a bend in a stream.

meniscus: the downward dip in the surface of water inside a graduated cylinder.

Mercalli Scale: a rating scale that measures the effects of an earthquake.

meridian: line of longitude. It runs from the North Pole to the South Pole. All meridians intersect at the poles.

metallic luster: shining like a polished piece of metal.

meteor shower: a period when many meteors streak into the atmosphere at once.

meteor: a streak of light caused by a small particle from space burning up in the atmosphere.

meteorite: a large meteor that survives the fiery entry through the atmosphere to strike the ground.

meteoroids: any small particle flying through space.

meteorology: the study of the atmosphere, primarily the study of weather.

minute of arc: one/60 th of a degree of angle.

Moho discontinuity: sudden change in the speed of seismic waves when they cross the Moho.

Moho: the boundary between the crust and the asthenosphere.

Mohs scale of hardness: a rating system from 1 to 10 for measuring a mineral’s hardness.

monominerallic: a rock made up of only one mineral.

mountain barrier effect: mountains acting as a barrier for rain.

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neap tide: a tide where high tide is not very high and low tide is not very low.

non-renewable: resources that are gone forever once they are used.

nor’ easter: a low pressure storm where the most intense portion has winds coming out of the northeast.

nucleus (comet): the icy core of a comet.

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observation: information gathered using any of the five senses. Taking a measurement is also an observation that uses technology to extend the senses.

occluded front: a combination of a cold front and a warm front.

oort cloud: a region at the far end of the solar system where most of the comets come from.

ore: raw rock material from which resources are extracted.

orographic effect: air being forced to rise and cool as it crosses a mountain range. Moisture will be forced out of the air as it rises.

outcrop: an exposed section of bedrock.

oxbow lake: a meander that was cut off of a stream.

oxidation: a chemical process where oxygen reacts with a mineral.

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Pangaea: ancient super continent made from most of the Earth’s land masses.

parallax: the apparent shifting of an object’s position caused by our movement from one location to another.

parallelism: the axis of rotation continues to point to the same spot in space as the Earth moves around the Sun.

parsec: the distance an object will be if it appears to shift by 1 second of arc.

penumbra: the lighter shadow in an eclipse.

percent deviation: calculation of how incorrect a measurement is.

period of revolution: the amount of time it takes for a planet to travel around the Sun.

permeability: the ability of water to travel through a material.

physical weathering: breaking down of rock material by physical force.

plane of earth's orbit: the flat surface which the Earth travels on as it orbits the Sun.

planet: a large body that orbits the Sun.

plate boundary: the edge of a solid slab of crust.
convergent plate boundary: place where two plates are crashing into each other.

plate tectonics: the study of the motions of the plates and within the astheno sphere.

plutonic: an igneous feature formed inside the Earth.

polar air mass: a cold air mass.

polyminerallic: a rock made up of more than one mineral.

pores: the empty spaces between the sediments in the soil.

porosity: a measure of how much empty space there is between sediments in a soil.

porphyry: coarse-textured crystals surrounded by a fine-grained matrix.

potential energy: the energy that comes from an object’s height.

pressure unloading: the expansion of a rock caused by the release of pressure when a rock gets exposed at the surface of the Earth.

prevailing wind: the typical direction that the wind will come from in an area.

Prime Meridian: the starting point for longitude. It is a line that goes from the North Pole through Greenwich , England to the South Pole.

psychrometer: a device with two thermometers used for measuring dew point and humidity.

pulsar: the rapidly spinning core of an exploded star.

P-wave: the primary wave from an earthquake that travels fastest and reaches distant seismic stations first.

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radiation: heat transfer as a form of light.

radioisotope: a variety of an element that is unstable and will decay.

rate: how quickly a value changes in time.

recharge basin: a large pit dug in the ground to give rain water easy access back into the aquifer.

red giant: a large cool star.

regional metamorphism: a metamorphic change in rock caused by extreme heat and pressure.

relative humidity: the amount of moisture in the air compared to the amount of moisture the air can hold.

relative time: placing events in order of which came first and which came second.

relief: the amount of elevation change in an area. It is “how bumpy an area is”.

residual soil: soil that stays above the bedrock that formed it.

resinous (waxy): shining like a piece of plastic.

retrograde motion: moving backwards.

revolution: an orbit around a star or a planet.

rhombohedral cleavage: breaking into slanted cubes where the corners do not meet at 90 degrees.

Richter Scale: a rating scale that measures how much energy was released during an earthquake.

Ring of Fire: the nickname given to the Pacific rim because of all the seismic activity.

root action: a type of physical weathering caused by roots breaking apart rocks.

rotational period: the amount of time it takes for a planet to spin.

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saturated: when air is holding as much water as it can.

scale: the ratio between an object on a map and an object in the real world.

sea breeze: wind that comes from the sea during the day.

second of arc: one/60 th of a minute of arc.

seismic wave: vibration from an earthquake that travels through the Earth.

shadow zone: an area on the opposite side of the Earth from an earthquake where no seismic waves are detected. It is a zone that is 102 degrees to 140 degrees away from the earthquake.

shield volcano: a very wide, gently sloping volcanic mountain made from lava flows.

sidereal day: a 360 degree turn around an axis. Using a distant star to mark the passage of one day. 23 hours, 56 minutes.

solar day: marking the passage of one day based on the position of the Sun. 24 hours.

solar eclipse: the Sun appears to get dark as the moon gets in between the Earth and Sun.

source region: the area that an air mass comes from.

specific heat: a measure of how much energy it takes to heat up one gram of a material.

spectrum: the different colors of light including those we can’t see.

spring tide: a tide where high tide is very high and low tide is very low.

spring: a place where ground water flows out of the ground.

star trail: the streaking of a star in a photograph caused by Earth’s rotation.

star: a large ball of gases that glows from energy created by fusion.

stationary front: a place where two air masses meet, but neither one is advancing on the other.

storm surge: a dome of high water level underneath a strong low pressure system.

streak: the color of powdered mineral.

sublimation: a phase change from solid directly into gas skipping the liquid phase. It can also be from gas to liquid.

supernova: a violent explosion at the end of a star’s life.

superposition: a principle that is used in relative time that places the oldest layer of rock at the bottom.

suspension: small particles that are carried within flowing water.

S-wave: the secondary wave from an earthquake that travels slower and reaches distant seismic stations second.

synodic month: a month marked from one full moon to the next full moon.

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terminator: line separating day and night.

terrestrial planet: a small rocky Earth-like planet.

The Principle of Original Horizontality: sedimentary rocks are normally made flat and horizontal.

till: unsorted sediments of greatly varying sizes that are deposited by glaciers.

time zone: a section of the Earth approximately 15º in longitude wide where all the clocks are set to the same time.

time-temperature lag: time difference between the strongest sunlight and the hottest time.

topographic map: a map showing the shape of the land using contour lines.

topography: the shape of the land.

tornado: a strong, compact storm with high winds.

trace fossil: the preserved indirect evidence of life such as footprints and burrows.

transform plate boundary: place where two plates are sliding past each other.

transpiration: the process of water vapor leaving the leaves of plants.

transported soil: soil that was formed in one location and transported to a different location.

tropical air mass: a warm air mass.

tropical depression: an organized low pressure system with heavy rain and winds less than 38 mph.

tropical storm: an organized low pressure system with heavy rain and winds between 39 mph and 73 mph.

troposphere: the lowest layer of the atmosphere in which all weather takes place.

tsunami: a large ocean wave caused by an earthquake.

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umbra: the dark portion of the shadow during an eclipse.

unconformity: a buried erosional surface. It represents a gap in the rock history.

u-shaped valley: a wide valley carved out by glaciers.

velocity: a fancy word that means speed. Technically, it is a combination of speed and direction.

vertical sorting: separating of sediments in size order with the biggest and heaviest at the bottom and the smallest and lightest at the top.

vesicle: a bubble in an igneous rock.

vitreous (glassy): shining like a broken piece of glass.

volcanic time marker: a layer of volcanic dust that gets deposited almost instantly over a very wide area.

volcanic: an igneous feature formed on the surface of the Earth.

v-shaped valley: valley carved by flowing water.

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waning: phases of the moon where it is getting dimmer from night to night.

warm front: the leading edge of an incoming warm air mass.

water cycle: a description of how water recycles itself around the planet.

water displacement method: finding the volume of an object by measuring the volume of the water it pushes out of a container.

water dissolution: a type of chemical weathering caused by watering dissolving soluble minerals.

waxing: phases of the moon where it is getting brighter from night to night.

weather: the current condition of the atmosphere.

white dwarf: a small, but hot star.

windward: the side of a mountain that gets hit by wind.

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zenith: spot in the sky directly above you.

zone of aeration: area above the capillary fringe where the pores are filled with air.

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