L5 : ROCK BEHAVIORS UNDER STRESS Flashcards
3 TYPES OF STRESS
TENSIONAL STRESS
COMPRESSIONAL STRESS
SHEAR STRESS
Causes rocks to be pulled apart that result to lengthening and break apart.
Tensional Stress
Causes rocks to fold or fracture. It squeezes rocks together.
Compressional Stress
Happens when forces slide pass each other in opposite direction which results to slippage and translation.
Shear Stress
are formed when rocks experienced compressive stress and deformed plastically.
FOLDS
3 types of folds
Monoclines
Anticlines
Synclines
is a simple bend in the rock layers where the oldest rocks are at the bottom and the youngest are at the top.
Monoclines
Is a fold that arches upward where the oldest rocks are found at the center of an anticline. The youngest rocks are covered over them at the top of the structure.
Anticlines
Is a fold that bends downward which rocks are curved down to a center.
Syclines
A rock under ample stress can crack, or fracture.
Faults
3 types of faults
Normal Fault
Reverse Fault
Strike Slip Fault
most common faults at divergent boundaries. In relation to the footwall, it develops as the hanging wall drops down.
Normal Fault
This type of faults is most common at the convergent boundaries. It forms when the hanging wall moves up.
Reverse Fault
It is mostly common on transform plate boundaries. This type of faults formed when the walls move sideways.
Strike Slip Fault