Stress and Faults
How they Effect Earth's Surface
Stress
Force applied to a rock that changes its shape
Normal Fault
3 Types of Stress
1. Compression
2. Tension
3. Shearing
- crack or break in the crust caused by Tension
- creates a Hanging wall and a Footwall
- Hanging wall rests on the Footwall and slides down with tension.
Reverse Fault
- Same structure as a Normal Fault but caused by different stress - Compression
- Hanging wall slides up the footwall.
Fault Block Mountains
Mountains that form when 2 Normal faults develop near each other.
Faults
Breaks in the Crust caused by Stress
Shearing
Strike-Slip Fault
- Crust on either side of the fault slips passed each other sideways because of Shearing.
- Can be an angular or vertical fault
Force between two rock plates sliding passed each other in opposite direction
Tension and Compression
Tension - a force that stretches rock until it becomes thinner in the middle
Compression - a force that squeezes rock together
until it folds, bends, or breaks
When the crust is compressed and bends/folds it forms:
- Anticlines - upward folds
- Synclines - downward folds
Once they get large enough they become Mountain Ranges.
- Appalachians
- Himalayas
- Alps