Chapter 4-7 mini poster

by: leo and jaylan

How plate boundaries cause earthquakes and volcanoes?

Volcanoes are caused by oceanic and continental plates, when the oceanic plate starts subducting and the continental plates go over the oceanic. Earthquakes are caused by transform boundaries, two continental plates are sliding past each other slowly and if they get caught on each other eventually they will cause a earthquake.

Divergent, Convergent, and Transform boundaries

  1. At divergent boundaries, plates move away from each other. The Mid-Atlantic Ridge is a divergent boundary.
  2. At convergent boundaries, plates move toward each other. The Cascadia subduction zone in the US Pacific Northwest is a convergent boundary.
  3. At transform boundaries, two plates slide past each other. The San Andreas fault in California occurs at this type of plate boundary.


The Cascadia subduction zone is a convergent plate boundary that stretches from northern Vancouver Island to northern California. It is a very long sloping subduction zone fault that separates the Juan de Fuca and North America plates.The Mid-Atlantic Ridge is a mid-ocean ridge, a divergent tectonic plate or constructive plate boundary located along the floor of the Atlantic Ocean, and part of the longest mountain range in the world. The San Andreas Fault is a continental transform fault that extends roughly 1300 km through California. It forms the tectonic boundary between the Pacific Plate and the North American Plate, and its motion is right-lateral strike-slip