Plate Boundaries

Plate Boundaries

Form 1 Geography

Plate Tectonics

• The Earth's crust is broken into several pieces known as plates.

• The place where two plates meet is known as a plate boundary.

• These plates float around on the mantle in a process known as plate tectonics.

The Earth's Plates

• The Earth's plates are divided into 7 major and 8 minor plates.

• Major plates are very large and usually contain continental landmasses and oceans.

• Minor plates contain smaller land masses and seas.

Multiple Select

Select the facts that are TRUE about major plates.

• They are very large.

• They hold continents.

• They are under the sea.

• There are 9 of them.

Where are the Earth's plates?

The Caribbean Plate

• The Caribbean plate is surrounded by the following plates.

• North American

• Cocos

• Nazca

• South American

Multiple Choice

Which of the following IS NOT a name of a plate on the Earth?

• Indian

• Naza

• Caribbean

• Scotia

Multiple Choice

We live on the ___ plate.

• North American

• Nazca

• Caribbean

• Cocos

Multiple Choice

Which of the following plates can be found NEXT TO the Caribbean plate?

• Indian

• Cocos

• Caribbean

• Scotia

Plate Boundaries

• The area on the Earth's crust where two plates meet is called a plate boundary or plate margin.

• Plate margins experience a lot of earthquakes and volcanic eruptions.

Plate Boundary Movement

• Plate boundaries can move in one of three directions:

• Towards each other at a convergent plate margin

• Away from each other at a divergent plate margin

• Past each other at a transform plate margin

Ring of Fire

• The Ring of Fire is a an area near the Pacific plate where most volcanic and seismic activity takes place.

Convergent Plate Boundary

At a convergent plate boundary, the Earth's plates come together.

They are also called destructive plate boundaries.

Convergent Plate Boundary

• At a convergent plate boundary two pieces of crust come together.

• If the oceanic and continental crust meet, the oceanic crust is pulled down (subducted) into the mantle.

• The crust then melts and forms new mantle.

• If two pieces of continental crust meet, they are pushed up to form a fold mountain.

Convergent Plate Boundary Features

• Volcanoes

• Fold mountains

• Trenches

• Hotspots

Divergent Plate Boundary

At a divergent plate boundary, the Earth's plates move apart.

They are also called constructive plate boundaries.

Divergent Plate Boundary

• At a divergent plate boundary, two pieces of crust move away from each other.

• As the pieces of crust away from each other, material from the mantle is able to rise to the surface and cool which forms new land.

• If this process takes place under the ocean, it is called seafloor spreading.

Divergent Plate Boundary Features

• Volcanoes

• Ridges

• Rifts/Rify Valleys

Transform Plate Boundary

At a transform plate boundary, the Earth's plates slide past each other.

The friction of this process results in earthquakes.

They are also called conservative plate boundaries.

Review time!

Multiple Select

The area where two or more plates meet is called a _____.

• Plate line

• Plate boundary

• Plate edge

• Plate margin

Multiple Choice

Two plates spread or move apart at what boundary?

• Convergent

• Divergent

• Transform

Multiple Choice

Plates slide past one another at ___ boundaries.

• Divergent

• Convergent

• Transform

Multiple Choice

A destructive plate boundary is another name for a ___ plate boundary.

• Divergent

• Convergent

• Transform

Multiple Choice

A destructive plate boundary is another name for a ___ plate boundary.

• Divergent

• Convergent

• Transform

Multiple Choice

New crust forms along a(n)

• subduction zone

• divergent boundary

• convergent boundary

• transform boundary

Multiple Choice

New crust forms along a(n)

• subduction zone

• divergent boundary

• convergent boundary

• transform boundary

Multiple Choice

When two continental plates converge (collide) what type of crustal feature is formed?

• Mid Ocean Ridge

• Subduction Zone

• Rift Valley

• Folded Mountains

Multiple Choice

When two continental plates converge (collide) what type of crustal feature is formed?

• Mid Ocean Ridge

• Subduction Zone

• Rift Valley

• Folded Mountains