1. Plate Tectonics

2. A tectonic plate is a piece of the Earth’s crust that slides on top of the mantle layer.
There are two kinds of plates: continental and oceanic
There are seven major plates and many smaller ones.
The major plates are:
N. American
S. American
African
Australian
Eurasian
Antarctic
Pacific

4. Tectonic plates Move because of convection currents in the mantle layer. The mantle is very hot near the core, so it becomes less dense and rises up towards the crust. Once the mantle reaches the crust it cools, becomes more dense and sinks back down toward the core.

6. When tectonic plates move, earthquakes can happen.
Mountain ranges and volcanoes are also created.
Large cracks called ridges and faults also form when plates move.
There are 4 kinds of movement:
Transform
Divergent
Convergent
Subduction

7. San Andres Fault
Earthquakes happen here.
The two plates that created the San Andreas Fault are the North American and Pacific Plates. The type of plate movement that created this fault is a transform boundary. The two plates move side by side in opposite directions.

8. Transform boundaries often create earthquakes.

9. Mid Atlantic Ridge
The two tectonic plates that created the Mid Atlantic Ridge are the North American and Eurasian Plates. The type of plate movement that created this ridge is a divergent boundary. The Mid Atlantic Ridge is located on the floor of the Atlantic Ocean and creates new crust as the two plates move away from each other.

10. A convergent plate movement created these mountains when the Eurasian and the Indo-Australian plates collided into each other. These are both continental plates, so neither one subducts underneath. Instead the plates are folded and uplifted into a mountain range.
Himalayan Mountains

11. Here are some examples of two continental plates smashing into each other at a convergent boundary.

12. Subduction Zone
The oceanic plate dives below the continental plate. The plate melts back into the mantle and creates a hot spot. The hot mantle rises up through the crust and creates volcanoes. An example of this in the United States is Mt. St. Helens.
continental plate
oceanic plate
Hot Spot

13. Before

14. After