1. Evidence for Continental Drift
4. CLIMATE EVIDENCE
Layers of coal were found in polar regions
Glacial deposits were found in tropical and temperate regions

2. Why was Wegener’s hypothesis rejected?
1. Wegener could not explain what was causing the continents to move.

3. What is theory is currently accepted?
The theory of plate tectonics:
Earth broken into shifting tectonic plates
The plates move by a hot mantle up to a few inches a year.

4. Folds, Faults, & Mountains
Stress is a force that can deform rocks.
Three types of stress:
Compression
Tension
Shear

5. Types of Stress Compression: opposing forces directed inward
Tension: pulling an object in opposite directions
Shear: Opposing stress is created by two plates moving in opposite directions

6. Types of Stress

7. How does stress effect rocks?
Elastic: rock stretches without breaking, returns to original shape after stress is removed.
Plastic: slow stretch does not return to original shape
Rupture: a break in the rock.

8. Folds & Rock Layers Rock is layered down in nature in flat sheets
A fold is a bending of rocks of the Earth’s crust.
Types of folds:
Anticline
Syncline

9. Folds & Rock layers Anticline If the fold is convex upward
Older rocks on inside

10. Folds & Rock layers Syncline If the fold is convex downward
Older rocks on outside

11. Faults & Rock Layers IMPORTANT  NEED TO KNOW!!!
Occurs when large stress builds up in the crust .
Types of Faults:
Normal
Reverse
Strike-Slip

12. Faults & Rock Layers Normal Fault
Hanging wall moved downward relative to footwall.

13. Faults & Rock Layers Reverse Fault
Hanging wall rises relative to the footwall.
Opposite of a normal fault

14. Faults & Rock Layers Strike-slip Fault
A vertical fracture where the blocks have moved horizontally.

15. Folds, Faults, Mountains Overview