1. Chapter 7
Plate Tectonics

2. Chap 7, Sec 4 (Deforming the Earth’s Crust)
Objectives:
Describe the three types of stress (force) that deform rocks.
Explain the differences between the three major types of faults.

3. Tech Terms:
deformation – the change in the shape of rock in response to stress.
stress – a force that acts on rock to change its shape or volume.

4. 3 types of stress:
shearing –when rock is pushed in opposite directions
tension - pulls on the crust, stretching rock so it becomes thinner in the middle
compression – squeezes rock until it folds or breaks

6. 3 types of faults:
3. normal fault – tension creates this fault at divergent boundaries. Occur along the Rio Grande rift valley.

7. 4. reverse fault – compression creates this fault at convergent boundaries. Occurs along the Appalachian Mountains.

8. 5. strike-slip fault – shearing creates this fault at transform boundaries. Occurs along the San Andreas Fault in California.