1. Earthquakes & Volcanoes
Plate Tectonics
Crustal Movement
Continental Drift
Plate Tectonics
Earthquakes & Volcanoes

2. CRUST:
The rocky outer surface of the Earth
Crustal Movement
When layers of sedimentary rock are disturbed after they have been deposited (laid down)
Sedimentary rocks are deposited in horizontal layers called “beds” or “strata”
What kinds of things do you think could make the Earth’s crust move and change?

3. Evidence Suggesting Minor Changes in the Earth’s Crust
The Principle of Original Horizontality
When sedimentary rock layers are laid down in horizontal layers

4. Deformed Strata Any sedimentary layer that is no longer horizontal
Three Main Types:
Folded
Layers that are bent or wavy
Tilted
Layers that are at an angle
Faulted
Layers that do not match up

5. Folded Strata

6. Tilted Strata

7. Faulted Strata

8. Uplifting / Subsidence
Layers are pushed up
Subsidence
Layers sink due to
accumulation

9. Major Events That Cause Crustal Movement
Earthquakes,
Volcanoes,
And
Plate Movements