Convection Currents

• What are convection currents?


  The process where hot magma rises and cool magma sinks creating a cycle.
• What drives the movement of tectonic plates?

  Convection currents
• What are the main layers of the Earth?

  • Inner core
  • Outer core
  • Mantle
  • Crust
• Describe the process of convection currents.


  The hot inner and outer core heats the mantle. The hot material then rises until it reaches the crust. It then moves sideways underneath the crust, creating friction with the crust above. This moves / drags the tectonic plates. As it is now thousands of km away from the core, its heat source is lost and the mantle material cools and sinks back down to the base of the mantle where the whole process starts again as the mantle material is reheated.
• What is slab pull?


  It is when the weight of the plate sinking into the mantle pulls onto the plate behind it.
• Explain why tectonic plates move? (3 marks)


  Convection currents causes material to be heated and rises. The heated material is then pulls along the plates due to friction while moving sideways. The heated material falls because it is too far away from its heat source and the cycle repeats.