APES Unit 4 : Earth Systems and Resources

Plate Tectonic Theory

theory that Earth's lithosphere is divided into tectonic plates

-these tectonic plates move slowly on top of the asthenosphere

tectonic plates

a block of lithosphere that consists of the crust and the rigid, outermost part of the mantle

Lithosphere

A rigid layer made up of the uppermost part of the mantle and the crust.

Asthenosphere

The soft layer of the mantle on which the tectonic plates move

divergent boundary

A plate boundary where two plates move away from each other.

convergent boundary

A plate boundary where two plates move toward each other.

transform boundary

A plate boundary where two plates move past each other in opposite directions

Weathering

The breaking down of rocks and other materials on the Earth's surface.

Sediments

small pieces of rock, soil, and other materials

Erosion

Processes by which rock, sand, and soil are carried away

Deposition

Process in which sediment is laid down in new locations.

transportation

the moving of sediments from one place to another

soil profile

All the vertical layers or horizons that make up a soil in a particular place

soil horizon

a distinct layer within a soil profile

soil erosion

wearing away of surface soi, especially topsoil, by water and wind

topsoil

Mixture of humus, clay, and other minerals that forms the crumbly, topmost layer of soil.

Porosity

The percentage of the total volume of a rock or sediment that consists of open spaces.

Permeability

Ability of rock or soil to allow water to flow through it

atmosphere

the layer of gases surrounding Earth

Troposphere

0-17 km above Earth's surface, site of weather, organisms, contains most atmospheric water vapor

Stratosphere

17 to 50 km, Ozone held here, absorbs UV radiation

Radiation

The transfer of energy by electromagnetic waves

convection current

the movement of a fluid, caused by differences in temperature, that transfers heat from one part of the fluid to another

Coriolis effect

The effect of Earth's rotation on the direction of winds and currents.

trade winds

prevailing winds that blow from east to west from 30 degrees latitude to the equator in both hemispheres

watershed (drainage basin)

land area that delivers runoff, sediment, and dissolved substances to a stream

Insolation

incoming solar radiation

Solstice

The two days of the year on which the sun reaches its greatest distance north or south of the equator

Equinoxes

the time or date (twice each year) at which the sun crosses the celestial equator, when day and night are of equal length (about September 22 and March 20).

weather

The condition of Earth's atmosphere at a particular time and place.

climate

The average weather conditions in an area over a long period of time

rain shadow effect

Precipitation falls on the windward side of a mountain range, resulting in lush vegetation & a warm, moist climate on one side, but a desert area on the leeward side.

Downwelling

The movement of water from the surface to greater depths.

Upwelling

the upward movement of ocean water toward the surface as a result of diverging currents

core

The central part of the earth below the mantle

Crust

Earth's outermost layer.

earthquake

Shaking and vibration at the surface of the earth resulting from underground movement along a fault

landslide

the sudden movement of rock and soil down a slope

Mantle

The layer of hot, solid material between Earth's crust and core.

mantle plume

a column of very hot rock rising up through the mantle

Minerals

A solid inorganic substance of natural occurrence with a specific chemical composition, and an orderly crystalline structure.

ozone layer

Protective layer in atmosphere that shields earth from UV radiation.

volcano

a mountain or hill, typically conical, having a crater or vent through which lava, rock fragments, hot vapor, and gas are being or have been erupted from the earth's crust.

Subduction

The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary.

bedrock

Rock that makes up Earth's crust; also the solid rock layer beneath the soil

clay

the finest soil, made up of particles that are less than 0.002 mm in diameter.

Humus

material formed from decaying leaves and other organic matter

fertilizer

a chemical or natural substance added to soil or land to increase its fertility

Loam

Rich, fertile soil that is made up of about equal parts of clay, sand, and silt.

sand

the coarsest soil, with particles 0.05,2.0 mm in diameter.

silt

fine particles of fertile soil with particles between 0.05 and 0.002mm in diameter

soil

The loose, weathered material on Earth's surface in which plants can grow.

atmospheric pressure

the pressure caused by the weight of the atmosphere

low pressure

A mass of rising warm air that usually bring wet, stormy weather.

high pressure

A mass of sinking cool air that usually bring fair weather.

relative humidity

The percentage of water vapor in the air compared to the maximum amount of water vapor that air can contain at a particular temperature

plate boundary

the region where two tectonic plates are in contact

hot spot volcanoes

• A hot spot is an area where material from deep in the mantle rises and then melts, forming magma

El Nino

a warming of the ocean water along the western coast of South America

La Nina

A cooling of the ocean surface off the western coast of South America,

O Horizon

The organic horizon at the surface of many soils, composed of organic detritus in various stages of decomposition

A Horizon

topsoil with the most nutrients

E Horizon

A zone of leaching, or eluviation, found in some acidic soils under the O horizon or, less often, the A horizon

Eluviation

the washing out of fine soil components from the A horizon by downward-percolating water

Illuviation

deposit of leached material in lower soil layers (B horizon)

B Horizon

A soil horizon composed primarily of mineral material with very little organic matter

C Horizon

The least-weathered soil horizon, which always occurs beneath the B horizon and is similar to the parent material.

R Horizon

The bedrock, which lies below all of the other layers of soil.

Percolation

The downward movement of water through soil and rock due to gravity.

Turbidity

A measure of how much light is unable to pass through water (How cloudy is the water)

Exosphere

the outermost region of Earth's atmosphere.

Thermosphere

The uppermost layer of the atmosphere, in which temperature increases as altitude increases

Ionosphere

the lower part of the thermosphere, where electrically charged particles called ions are found

Auroras

a natural electrical phenomenon characterized by the appearance of streamers of reddish or greenish light in the sky, usually near the northern or southern magnetic pole.

Mesosphere

The layer of Earth's atmosphere where clouds stop forming and meteors burnout