READ: Important Vocabulary Terms

These are the most important vocabulary terms to learn this week. Please make sure you understand these terms. 

• Divergent plate boundaries: the two plates move away from each other.
  
• Convergent plate boundaries: the two plates move towards each other.
  
• Transform plate boundaries: the two plates slip past each other.
• Continental Rifting: when a divergent plate boundary occurs within a continent.  
• Ocean-Continent Convergence: When Oceanic crust collides with a continent. The oceanic plate is denser, so it undergoes subduction. This means that the oceanic plate sinks beneath the continent. This occurs at an ocean trench. 
  
• Subduction: When one plates moves down into the mantle beneath another plate. 
  
• Subduction zones are where subduction takes place.
  
• Continental Arc:  a volcanic mountain range near the coast of a continent created when an oceanic plate subducts and melts as it enters the mantle. Magma rises up and erupts creating mountains. 
  
• Ocean-Ocean Convergence: When two oceanic platescollide. The denser plate subducts beneath the less dense plate. As the subducting plate is pushed deeper into the mantle, it melts. The magma this creates rises and erupts. This forms an island arc.
  
• Island arc: a line of volcanoes created when oceanic plates collide. 
  
• Continent-Continent Convergence: when two continental plates collide. Continental lithosphere is low in density and very thick. Continental lithosphere cannot subduct. So when two continental plates collide, they just smash together. Earthquakes and metamorphic rocks result from the tremendous forces of the collision. But the crust is too thick for magma to get through. As a result, there are no volcanoes at continent-continent collision zones.
  
•  A tsunami is an enormous ocean wave or set of waves generated by an underwater earthquake.
  
• Fissures: long cracks in the ground.