igneous rocks

• Igneous rocks

  • Volcanoes
  • Lava
  • Magma
• How are igneous rocksformed


  • Formed when molten rocks COOL to form solid rock
  • Formed near volcanoes
  • Hard and made of interlocking crystals of different sizes
• Lava


  Molten rock outside the volcano
• Magma


  Molten rock underground inside the volcano
• Igneous rocks


  • Granite
  • Pumice
  • Basalt
• How cooling affects crystal size


  1. Extrusive igneous rocks (lava cools quickly so crystals don't have much time to grow, so crystals are small)

  2. Intrusive igneous rocks (magma cools inside the earth very slowly so crystals have more time to grow, so crystals are large)
• Extrusive igneous rocks


  • Formed on the surface of the earth
• Intrusive igneous rocks


  • Formed inside the earth