1. Plate Tectonics

2. Earth’s Layers
The Earth's rocky outer crust solidified billions of years ago, soon after the Earth formed.
This crust is not a solid shell; it is broken up into huge, thick plates that drift atop the soft, underlying mantle.

3. Here’s the HS EES version…

4. How Plates Move

5. The Lithosphere & The Asthenosphere
The lithosphere floats on top of the asthenosphere. Convection currents that occur in the asthenosphere, cause the lithosphere to move. This then creates/destroys landforms on Earth’s crust.

6. Tectonic Plates

7. Continental Drift
Geologist Alfred Wegener-first to propose evidence that continents were once connected.
He called this “super” continent Pangaea, meaning “All Earth”

8. Pangaea

9. Political Pangaea

10. Support for Continental Drift
Shape of the continents
They fit together like jigsaw puzzle pieces.

11. Support for Continental Drift
2. Fossil Correlation SAME FOSSILS : DIFFERENT CONTINENTS

12. Support for Continental Drift
3. Rock and Mountain Correlation
SAME ROCK : DIFFERENT RANGE
Existing mountain ranges separated by vast oceans contain rocks of identical mineral content.
Ex: Appalachian Mtns in the eastern US and Caledonian Mtns in the British Isles

13. Support for Continental Drift
4. Past Climate Data (Paleoclimates)
Glacial Scars
SAME SCARS : DIFFERENT CONTINENTS
Coal Deposits
Have been found in temperate and polar regions, however coal is formed in tropical regions.

14. Glacial Scars

15. Coal Deposits

16. Continental Drift in Doubt
Why didn’t people believe in continental drift?
People couldn’t imagine how the Earth could be millions of years ago.
People couldn’t imagine a force great enough to move the continents.
BUT…by the 1960s, evidence would prove continental drift is TRUE!

17. Sea Floor Spreading

18. Sea Floor Spreading Harry Hess-1960s
Discovered the Mid-Atlantic Ridge while mapping the ocean floor.
Mid-Ocean Ridges-underwater mountain chains
Magma rises to the surface and solidifies to form new oceanic crust.
Older crust is pushed farther away from the ridge

19. Sea Floor Spreading

20. Plate Tectonics
The theory that Earth’s crust and upper mantle (lithosphere) are broken into sections, called plates, that slowly move around on the rest of the mantle (asthenosphere) due to convection currents.

21. Types of Crust
The type of crust present and the direction of the convection current determines how Earth’s surface will be effected.
Oceanic: made primarily of basalt; more dense
Continental: made primarily of granite; less dense

22. Different Types of Boundaries What are the three?

23. Divergent Boundary - Oceanic

24. Divergent Boundary - Continental

25. Convergent Boundary – Oceanic & Continental

26. Real World Effect: Nazca Plate, South American Plate Peru-Chile Trench

27. Convergent Boundary – Oceanic & Oceanic

28. Real World Effect: Japanese Islands

29. Convergent Boundaries - Continental

30. Eurasian Plate Indian Plate
What mountain range is this?
Indian Plate

31. Transform Boundary – San Andreas Fault

32. Warm-Up COPY & ANSWER each question, please!
Name the 3 main layers of the Earth
What is a tectonic plate?
What was Pangaea?
What is Sea-Floor spreading?
Name the three different types of plate boundaries and what type of landform occurs at each.