Types of Plate Boundaries

When 2 plates meet…..

• 1- They can crash together =

• ConvergentConvergent BoundaryBoundary OROR

• 2- They can move away from each other = Divergent Divergent BoundaryBoundary OROR

• 3- They can slide past each other = Sliding/Transform Sliding/Transform BoundaryBoundary

Convergent Boundaries• There are two types of Convergent

Boundaries:

–A. SubductionSubduction: when one plate is more densedense than another, the more dense plate goes underneathunderneath the less dense plate.

The 2nd type is collision

Subduction

Convergent Boundaries:Subduction

• One plate goes under the other

• Features that occur: Earthquakes, Volcanoes, Ocean Trench

Remember:

“The Ocean floor is going DOWN!!!!”

Example• Mt. St. Helens- Juan de Fuca plate goes

underunder the North American Plate.

What are some indicators that a volcano might erupt soon?

Convergent Boundaries, Collision– B. . CollisionCollision: when the 2 plates are the same

material. When they hit, they both buckle upbuckle up– (this makes mountains)

• The two plates have the same density, they buckle up and move to a higher elevation

• Features: Earthquakes, Folded Mountains

Example• Mt. Everest, Himalayas

• The plates are still colliding and gaining Elevation

What are some forces of nature that keep Everest from getting much higher?

Divergent Boundaries• When two plates

move apart.• Features:

– In continents: – Rift Valley,

Volcanoes, Earthquakes

– In oceans: – Mid-Ocean Ridge,

Volcanoes, Earthquakes

Examples:

• Great Rift Valley, Africa

• Mid-Atlantic Ridge, Atlantic Ocean

Example: Great Rift Valley, Africa

Sliding/Transform Boundary• When two plates slide past each other.

• Features: Earthquakes

Example:California- Pacific Plate

slides past the North American Plate at the San Andreas Fault.

Example: San Andreas FaultWhere is it?