Plate Boundaries

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 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.

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

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.

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.