tectonic plates

• What is a constructive plate boundary?

  A boundary where two plates move apart
• What is formed at constructive boundaries?

  New oceanic crust and mid-ocean ridges
• What is a destructive plate boundary?

  A boundary where two plates move towards each other
• What is formed at destructive boundaries?

  Deep ocean trenches and volcanoes
• What is a conservative plate boundary?

  A boundary where two plates slide past each other
• What hazards are associated with conservative boundaries?

  Earthquakes due to built-up friction
• Which boundary does not involve the creation or destruction of crust?

  Conservative plate boundary
• What is the main difference between oceanic crust and continental crust?

  Oceanic crust is thinner and denser.
• How are constructive plate boundaries formed?

  • Two tectonic plates move apart
  • Magma rises from the mantle
  • Fills the gap and cools
  • Forms new crust
• What features are formed at constructive boundaries?

  Mid-ocean ridges and volcanoes
• How are destructive plate boundaries formed?

  When two plates move towards each other
• What happens to the oceanic plate at destructive boundaries?

  It is forced beneath the other plate
• What features form at destructive boundaries?

  Volcanoes and ocean trenches
• What happens when an oceanic plate meets a continental plate?

  The oceanic plate subducts beneath the continental plate
• What occurs when two continental plates collide?

  The crust crumples and forms mountains
• How are conservative plate boundaries formed?

  • Two plates slide past each other
  • No crust is made or destroyed
• What is a danger associated with conservative boundaries?

  Earthquakes due to pressure build-up
• What are the main features of oceanic and continental crust?

  • Oceanic crust: thinner, denser, basalt
  • Continental crust: thicker, less dense, granite