1
2
3
4
5
100

to move around something

orbit

100

imaginary line that runs through the earth's center from the North Pole to the South Pole

axis

100

a complete trip around the sun

revolution

100

thin layer of gases that envelope the earth

atmosphere

100

beginning of summer

solstice

200

large, continuous mass of land

continent

200

a region of reduced rainfall on one side of a high mountain 

rain shadow

200

water deposited on the earth in the from of rain, snow, hail sleet or mist

precipitation

200

when day and night in both hemispheres are the same length

equinoxes

200

average weather conditions in a region or area over a longer period

climate

300

giant ocean wave caused by volcanic eruptions or movement of the earth under the ocean floor

tsunami

300

the result when rocks on one side or both sides of a crack in earth's crust are moved with forces within earth

fault

300

16 enormous pieces that make up earth's crust

tectonic plates

300

caused by plate movements along fault lines

earthquakes 

300

long, narrow band of volcanoes

Ring of Fire

400

process by which earth's surface is worn away by forces such as wind, rain, chemicals and the movement  of ice and flowing water

weathering

400

process by which weathered bits of rock are moved elsewhere by water, wind or ice

erosion

400

can be flat or have a gentle roll and can be found along coastlines or far inland

plains

400

land that rises above surrounding land

plateau

400

narrow strip of land connecting two larger pieces of land

isthmus

500

earth's recycling system for water

water cycle

500

area where sand, silt, clay or gravel is deposited at the mouth of a river

delta

500

water contained inside the earth's crust

groundwater

500

long, narrow, steep-sided cut in the ground or the ocean floor

trench

500

underwater plain that borders a continent

continental shelf