volcanoes

• Tectonic plates


  Random jagged shapes that the Earth's outer layer (crust) is divided into
• Plate margins/boundaries


  Where the tectonic plates meet
• Types of plate margins

  • Destructive
  • Constructive
  • Conservative
• Destructive plate margins


  • Plates collide towards each other
• Constructive plate margins


  • Plates pull apart
• Conservative plate margins


  • Plates move side by side in different directions or at different speeds
• Formation of volcanoes


  Volcanoes are only formed at destructive and constructive plate margins
• Formation of destructive volcanoes

  1. Two plates collide, with the denser oceanic plate sinking/subducting beneath the continental plate

  2. The heat and pressure causes the oceanic plate to melt into a pool of magma

  3. The magma rises back up through cracks in the crust called vents

  4. This forms destructive or composite volcanoes
• Formation of constructive volcanoes

  1. Two plates move away from each other, creating a gap

  2. Magma rises up and fills this gap

  3. This creates a shield volcano, e.g. the Hawaiian islands
• Volcanoes are only formed at destructive and constructive plate margins