Earth's Interior

Earth layers from core up

Inner core, outer core, mantle, crust

Crust

• Solid rock

• 5km - 50km thickness less than 1% average radius

Mantle

• Rock minerals ie silicon dixoide, magnesium oxide, iron oxide and calcium oxide

• Mostly solid but over geological timescles it behaves like thick liquid

• 500 kelvin near surface

• 4200 kelvin near core

Outer core

• Heavier elements eg Iron + Nickel;

• When Earth first formed it was a big molten ball. Heavy elements sank to the centre, pushing lighter elements to the top.

• 8000 kelvin 

• Liquid therefore moves around transporting heat from the core up. 

• Produces Earth’s magnetic field

Inner core

• Heaviest elements eg. Iron + Nickel

• Hottest, hotter than surface of the Earth

• But it’s solid because metals melting point increase with pressure. Pressure in inner core keeps it solid.