Plate tectonics

• What are seismic waves?

  Shockwaves released by tectonic movements
• How do convection currents help tectonic plates move?

  The heat produced by the decay of radiaocative elements in the Earth's core heats the lower mantle, creating convection currents which cause the plates to move
• How does slab pull help tectonic plates move?

  Newly formed oceanic crust at mid ocean ridges becomes denser and thicker as it cools, causing it to sink into the mantle under its own weight and pulling the rest of the plate further down with it
• How does subduction help tectonic plates move?

  As two oceanic plates move towards each other, one slides under the other into the mantle, where it melts in an area known as the subduction zone
• How does seafloor spreading help tectonic plates move?

  Hot magma is forced up from the asthenosphere and hardens, forming new oceanic crust which pushes the tectonic plates apart
• What are plate boundaries?

  The locations where two tectonic plates meet, and where the most natural disasters occur
• What are plate margins?

  Boundaries where tectonic plates meet
• What is a convergent plate boundary?

  A boundary where two plates collide, also known as destructive margins
• What is a divergent plate boundary?

  A boundary where two plates divide, also known as constructive margins
• What are conservative plate boundaries?

  A boundary where two plates slide past each other, also known as transform margins
• What natural disasters occur at convergent plate boundaries?

  Earthquakes and volcanic eruptions
• What natural disasters occur at divergent plate boundaries?

  Volcanic eruptions
• What happens when an oceanic plate converges with a continental plate?

  Because the oceanic plate is denser than the continental plate, subduction occurs, and this forms deep ocean trenches
• What happens when an oceanic plate converges with an oceanic plate?

  The denser oceanic plate subducts beneath the other, forming deep ocean trenches
• What happens when a continental plate coverges with a continental plate?

  Because both plates have the same density, neither plate is subducted and they collide instead, forcing sediment upwards that forms mountains