Structure of earth

• The earths surface is separated into tectonic plates
• structure of the earth:

  • the centre: CORE
  • 2 parts of the core: inner and outer
  • Inner is a ball of solid iron and nickel
  • Outer core is liquid
• Structure of the earth:

  • around the core: MANTLE
  • made up of semi-molten rock that moves very slowly
• structure of the earth:

  • on the top: CRUST
  • 10-70km thick
  • Divided into slabs called tectonic plates that float on the mantLe
  • 2 types of crust: continental and oceanic
• oceanic crust is thinner and more dense

  continental crust is thicker and less dense
• Tectonic plates move due to convection currents in the mantle

  • low parts of the mantle are hotter as they are heated by the core
  • This makes it less dense as they heat up and rise
  • Move to the top of the mantle where is cools down and sinks
  • Creates circular movements which move the tectonic plates