canyon

canyon: a deep ravine between cliffs often carved from the landscape by a river over a long period of time

delta

delta: a large, flat area of land at the mouth of a river

landform

landform: a natural structure on Earth’s surface

dune

dune: a hill of sand that is deposited by the wind

weathering

weathering: the various processes that cause exposed rock to break down

 

physical weathering

physical weathering: the breakdown of rocks and soils through direct contact with heat, water, or ice

erosion

erosion: the movement of weathered materials by

water, wind, or ice

deposition

deposition: the process in which materials eroded by water, wind, or ice are dropped in a new place

mass movement: the downhill movement of rock and soil because of gravity

mass movement

sedimentary rock: a rock that formed when sediments were pressed and cemented together

sedimentary rock

cementing: sediments glued together by minerals dissolved in water

cementing

fossil: a remnant or trace of an organism from long ago, such as a skeleton or leaf imprint, embedded and preserved on the Earth’s crust

fossil

fossil fuel: a fuel that formed from the decayed remains of ancient plants and animals

fossil fuel

alternative energy: any energy from a source that does not use up the Earth’s natural resources or endanger our environment

alternative energy

solar energy: energy from the sun that is converted into thermal or electrical energy

solar energy

wind energy: air in motion

wind energy

hydroelectric energy: electricity that is generated by water power

hydroelectric energy

geothermal energy: energy from within the Earth

geothermal energy

biofuels: fuels that can be produced using organic materials made from plants and animals

biofuels

force: a push or pull

force

gravity: the force that pulls objects toward each other

gravity

friction: a force between two surfaces rubbing against each other; friction works against motion

friction

magnetism: a force that pulls magnetic materials across a distance

magnetism