Geology Final Exam: Deformation

Card Set Information

Geology Final Exam: Deformation
2013-12-14 23:29:02
Geology Final Exam Deformation

Geology Final Exam for Deformation
Show Answers:

  1. Define stress
    The force applied to a given area
  2. Define strain
    Changes, caused by stress, in the shape or size of a rock body
  3. What are the 3 types of differential stress and what type of deformation do they cause?
    Compressional Stress: shortens/thickens a rock unit. Causes folding.

    Tensional Stress: elongates/thins a rock unit

    Shear Stress: causes adjacent parts to slide by one another; smears/tears a rock unit

    • Compressional Stress (Divergent)
    • Tensional Stress (Compressional)
    • Shear Stress (Tensional)
  4. Define deformation
    All changes in the original form and/or size of a rock body (folds, faults, joints).
  5. What are Anticlines?
    Up folded or arched rock layers(oldest material)
  6. What are Synclines?
    Downfolds/thoughs of rock layers(youngest material)
  7. Define Dome
    Upward displacement
  8. Define Basin
    Downward displacement
  9. What are folds?
    Flat level surfaces that have been bent or curved because of pressure and high temperature
  10. What are faults?
    Fractures is rocks along which movement has occurred.
  11. What is a joint?
    A fracture with no movement
  12. What is a hanging wall
    • Moves down relative to footwall
    • Results from tensional stress
  13. Describe the 3 types of faults, their associated forces, and specific examples of each.
    Normal faults(tensional) - Hanging wall moves down relative to the footwall. Fault block mtns.

    Reverse and thrust faults(compressional) - Hanging wall moves up relative to footwall.

    Right/left lateral faults - Dominant displacement is horizontal, parallel to the strike of the fault.