1. Plate Tectonics
Write on RIGHT Side

2. What discoveries support continental drift?
In mid 1900s, scientists found under-water mountain ranges called mid-ocean ridges. This discovery led to the Theory of Plate Tectonics

3. Theory of Plate Tectonics
Theory of Plate Tectonics Describes why and how the Earth’s surface changes
Theory of Plate Tectonics

4. Tectonic Plate- large piece of lithosphere that is floating on the asthenosphere
The word “Tectonic” is Greek for “builder”
Tectonic Plates build and shape our Earth (mountains, earthquakes, volcanos, etc.)
Tectonic Plates

5. Plates move at different speeds and in different directions
Oceanic plates are more dense than continental plates
Tectonic Plates

6. Why do tectonic plates move?
Mantle Convection– the rock rises and falls due to changes in density.
The rock heats and rises, then cools and sinks

7. Mid-Ocean Ridges Mid-ocean ridges form along cracks in the crust
Youngest rock is closest to the ridge, oldest rock is farthest away

8. Sea Floor Spreading the process where molten rock inside the Earth rises through the cracks in the ridges, cools, and forms new oceanic crust
Sea- Floor Spreading

9. Mid- Ocean Ridges forming and Sea-Floor Spreading

10. Reflection (Left Side)
Copy the information and draw the picture of convection taking place in the mantle
Reflection (Left Side)