Geology ~ Factors Affecting Stress and Strain

1) More plastic rocks will be folded, not faulted even if original rock is competent.

2) Strength increases with pressure. Rocks are more difficult to deform.

3) Pressure applied for a short time, reocks mat behave as brittle. Long time pressure is more likely to result in plastic deformation.

4) Forces pull rocks apart. Forces deplace rocks on either side of a fracture, creating a fault. No displacement means a joint is made.

5) Rocks pushed together by force. Shear forces: Result in deformation of rocks in one place.

6) Ooliths of fossils can be used to measure strain. Symmetrical fossils that become strained can gauge strain levels. (dependant on how uch they stretch and their direction).