The document describes three main types of plate boundaries: convergent boundaries, divergent boundaries, and transform boundaries. Convergent boundaries occur when plates collide and include ocean-ocean, ocean-continent, and continent-continent convergence. Divergent boundaries exist when plates move apart, such as at oceanic spreading ridges and ancient continental rift valleys. Transform boundaries occur when plates slide past each other horizontally along transform faults. Volcanoes form at ocean-ocean convergent boundaries and ocean-continent convergent boundaries where one plate subducts under the other.

1. Plate Boundaries

2. Types of Plate BoundariesConvergent BoundariesDivergent BoundariesTransform Fault Boundaries

3. Convergent BoundariesConvergent Boundaries exist when two plates are colliding together. There are three different types of Convergent Boundaries: Ocean:OceanOcean:ContinentContinent:Continent. Exists when two plates are being pushed together.

4. Ocean: Ocean ConvergentTwo oceanic plates colliding, one has to give and one goes down as the other one rises up. Most have the same density.Creates volcanoes and earthquakes caused by the faults.

5. ExampleThe Ring of Fire

6. Ocean:Continent ConvergentOceanic crust will always go down and the continental crust will always go up, because the continental crust is more dense.Earthquakes are caused by the trenches.Partial melting of oceanic and continental crust cause explosive magma.

7. ExampleThe Mariana Trench – Underwater Volcanoes!

8. Continent:Continent ConvergentCauses a lot of faults by the rocks pushing together. Potential for earthquake activity.No volcanoes because there is no subduction zone.Enormous mountain ranges.

9. ExampleEast Africa

10. Divergent Plate BoundariesExists when two plats are being pulled apart from one another.There are two different types of Divergent Plate Boundaries:Ocean:OceanContinent:Continent

11. Ocean:Ocean DivergentNew crust is being made.Underwater mountains and volcanoes exist.Also called a spreading center, the further away from the spreading center, the older the crust.

12. ExampleMid Atlantic Ridge

13. Continent:Continent DivergentWhen a continental crust is pulled apart, it causes a rift valley.Not making any new crust.

14. ExampleThe Appalachian Mountains

15. Transform Fault BoundaryExists when two plates are sliding past one another.There are two types of Transform Fault Boundaries:Ocean:OceanContinent:Continent

16. Ocean:Ocean or Continent:Continet Transform FaultSqueezed in different directions.As they move, earthquakes happen. They can be along side any other plate boundary.

17. ExampleThe San Andreas Fault

18. Which Plate Boundaries Cause Volcanoes?

19. Ocean:Ocean ConvergentOcean:Continent ConvergentOcean:Ocean Divergent