margins

• destructive/convergent plate margin


  • plates move towards eachother, movement can cause earthquake

  • the oceanic plate sinks below the continental plate this is subduction.

  • this happens because the oceanic plate is denser than the continental plate

  • plate sinks into mantle and melts to form magma, the pressure builds up & magma escapes and rises up through a composite volcano

  • when two continental plates collide neither sink & forms fold mountain called collision margin, earthquakes can occur here
• conservative plate margins


  • move past eachother, or side to side moving at different speeds

  •friction occurs and plates become stuck which builds pressure

  •when pressure is released it sends out huge amounts of energy, causing an earthquake

  • the earthquakes at a conservative plate boundary can be very destructive as they occur close to the earths surface

  • there are no volcanoes at a conservative plate margin
• how does a destructive plate margin move?

  plates move towards eachother, movement can cause earthquake, when the oceanic plate is forced underneath the continental plate this is subduction.
• how do conservative plate margins move? 


  move past eachother, or side to side moving at different speeds
• What is The Ring of Fire


  a string of volcanoes and sites of seismic activity, or earthquakes, around the edges of the Pacific Ocean
• how are earthquakes formed?

  at a destructive plate margin, oceanic crust subducts beneath continental crust. a lot of friction is created as plates move along eachother. the build up of friction will become so great the pressure is released in the form of an earthquake.
• how are volcanoes formed?

  • constructive - plates rip apart causing volcanic activity
  • destructive - one plate subducts beneath the other resulting in a line of volanoes overriding the plate
• what are convection currents?

  a movement within the Earth's mantle caused by the heat of the core
• constructive plate boundary

  • two plates move apart due to convection currents in the mantle
  • as the two plated move apart, magma rises up to fill the gap
  • This causes volcanoes since the magma can escape easily at the surface the volcano doesn't erupt with force