Kaarten: AQA GCSE Geography: Tectonic plates | Quizlet

the earth's inner core

a ball of solid iron in the middle of the earth

the earth's outer core

around the inner core, a liquid of iron and nickel

mantle

around the core, semi-molten rock that moves slowly

crust

outer layer of the earth

tectonic plates

An irregular section of the lithosphere that floats and moves on the earth's mantle due to convection currents

lithosphere

the solid part of the earth consisting of the crust and outer mantle

continental crust

thicker(30-50km), less dense, older crust making the continents

oceanic crust

thinner(5-10km), more dense, younger crust making ocean floor

granite

A usually light coloured igneous rock that is found in continental crust

igneous

A type of rock that forms from the cooling of molten rock at or below the surface.

plate margins/boundaries

where tectonic plates meet

destructive margin

denser oceanic plate is forced down into mantle and destroyed, often creates volcanoes and ocean trenches

constructive margins

where 2 plates are moving away from each other, magma rises from mantle to fill the gap and cools creating new crust

conservative margins

where 2 plates are moving sideways against each other, or moving in the same direction as each other but at different speeds, crust is not created or destroyed

destructive margin example

along the west coast of south America

constructive margin example

at the mid-Atlantic ridge

conservative margin example

along the west coast of the USA

seismic waves

vibrations that travel through Earth carrying the energy released during an earthquake