1. Investigation 4: Plate Tectonics
Earth systems
Investigation 4:
Plate Tectonics

2. Lesson Essential Question
Notes
Lesson Essential Question
What processes cause the Earth’s plates to shift?

3. Explain the evidence used to support the Theory of Plate Tectonics.
Notes
Lesson Objective
Explain the evidence used to support the Theory of Plate Tectonics.

4. The Theory of Continental Drift
Notes
The Theory of Continental Drift
- First Proposed by scientist, Alfred Wegener
- The evidence that Wegener proposed to support the idea that the continents move is also evidence that there are plates on Earth that are in motion

5. The Theory of Continental Drift
Notes
The Theory of Continental Drift
EVIDENCE PIECE 1: Continental Shapes The continents look as though they could fit together like pieces of a jigsaw puzzle

6. The Theory of Continental Drift
Notes
The Theory of Continental Drift
EVIDENCE PIECE 2: Fossil and Rock Patterns Fossils and rocks found on continents that are oceans apart but match up perfectly

7. The Theory of Continental Drift
Notes
The Theory of Continental Drift
EVIDENCE PIECE 3: Glacial Deposits
A. When the continents are put together they show a streamlined motion of the glacier from southern Africa and Northern Australia outward.
B. With the continents in their present positions, the deposits indicate erratic glacier motion. 

8. New evidence in support of plate tectonics
Notes
New evidence in support of plate tectonics

9. New evidence in support of plate tectonics
Notes
New evidence in support of plate tectonics
EVIDENCE PIECE 4: Sea Floor Age Maps
Scientists have discovered a distinct pattern in the age of oceanic crust

10. New evidence in support of plate tectonics
Notes
New evidence in support of plate tectonics
The newest oceanic crust is in the center and gets progressively older as you move towards the continents in a distinct pattern, indicating that there is definite movement of the ocean floor.

11. Atlantic Ocean Sea Floor Spreading Map

12. Pacific Ocean

13. Indian Ocean

14. The Process of Seafloor Spreading
Notes
The Process of Seafloor Spreading
Creation of New Oceanic Crust
- Occurs at Mid-Ocean Ridges
- Underwater chains of mountains found in the oceans
- Youngest rocks on the ocean floor are found here

15. The Process of Seafloor Spreading
Notes
The Process of Seafloor Spreading
Destruction of Old Oceanic Crust
- Occurs in a process called Subduction
- Old oceanic plates sink back into the mantle
- Creates a Trench
- a deep depression in the ocean floor

16. Plate Boundaries Notes
Divergent Boundary Plates are moving away from each other Convergent Boundary Plates come together and collide Transform Boundary Plates slide past each other in opposite directions

17. New evidence in support of plate tectonics
Notes
New evidence in support of plate tectonics
EVIDENCE PIECE 5: GPS and Satellites GPS stations set up all across the globe are moving toward or away from each other

18. What Causes Plate Tectonics?
Notes
What Causes Plate Tectonics?
Convection Currents - Form in the Earth’s Mantle - Caused by the heat generated from radioactive decay of elements in the mantle and core