KS3 Planet Earth

continental drift

The hypothesis that states that the continents once formed a single landmass, broke up, and drifted to their present locations

Pangea

A supercontinent containing all of Earth's land that existed about 225 million years ago.

Crust

The thin and solid outermost layer of the Earth above the mantle

Mantle

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

Outer core

the liquid layer of the Earth's core that lies beneath the mantle and surrounds the inner core

inner core

A dense sphere of solid iron and nickel at the centre of Earth

inner core, outer core, mantle, crust

List the layers of the Earth in order from inside to outside.

Continents

seven large landmasses on Earth's surface

tectonic plates

Sections of the Earth's crust that move due to convection currents.

convection currents in mantle

move tectonic plates on the crust

Fold mountains

mountains that form where two plates collide and force layers of rock into folds

plate boundary

the region where two tectonic plates are in contact

convergent boundaries

Occur where two tectonic plates slide TOWARD each other.

divergent boundaries

Where tectonic plates are spreading APART, new crust being formed (e.g. mid-ocean ridges, rift valleys).

transform boundaries

Places where tectonic plates slide along BESIDE one another as they move

Earthquakes happen when

There is a sudden movement in tectonic plates at a transform boundary

Volcanoes happen at...

locations where the mantle is exposed to the crust, where the crust is thin

Ring of Fire

A circle of volcanoes surrounding the Pacific Ocean.

Richter scale

A scale that rates an earthquake's magnitude based on the size of its seismic waves.

epicentre

the point on the Earth's surface directly above the focus of an earthquake

fault line

a break or crack in Earth's surface. Caused by shifting and moving plates.

seismograph

a device that measures the strength of an earthquake

water cycle

The continuous process by which water moves from Earth's surface to the atmosphere and back

Condensation

The change of state from a gas to a liquid

Evaporation

The change of a substance from a liquid to a gas

Precipitation

Any form of water that falls from clouds and reaches Earth's surface.

run off

water that flows over the ground surface rather than soaking into the ground

ground water

underground water that is held in the soil and in pervious rocks

transpiration

loss of water from a plant through its leaves

open water

oceans, seas and lakes where water gathers

greenhouse gases

Gases in Earth's atmosphere that trap heat near the surface

gases in the air

Nitrogen, Oxygen, Argon, CO2