Faults
What is a fault?
A fault is a fracture, or break, in the Earth's crust (lithosphere)
What is stress
The force applied to an object.
what are folds
Rocks deforming plastically under compressive stresses crumple into folds.
What are the three main categories of faults?
Normal fault, reverse fault/thrust fault, and transform/strike-slip fault
What are the 3 types of stress
Shear, Tension, and confining stress.
What are the three types of folds
Monocline, Anticline, andSyncline:
What is an Normal fault?
when two plates move away from each other, causing the hanging wall to slide down the foot wall.
What is shear stress
When forces are parallel but moving in opposite directions, the stress is called shear (Figure below). Shear stress is the most common stress at transform plate boundaries.
what is an anticline fold
An anticline is a fold that arches upward. The rocks dip away from the center of the fold.
What is a reverse/thrust?
When the plates are compressed, or pushed together, reverse or thrust faulting occurs. This means that the foot wall is hanging below the hanging wall plate was pushed up onto another plate.
What is tension stress
Rocks that are pulled apart are under tension. Rocks under tension lengthen or break apart. Tension is the major type of stress at divergent plate boundaries.
What is an Syncline fold
A syncline is a fold that bends downward. The youngest rocks are at the center and the oldest are at the outside.
What is the a transform/strike-slip fault.
Is when one where the relative motion is horizontal.
What is compression stress
Compression Squeezes rocks together, causing rocks to fold or fracture. It happens at convergent plate boundary.
what is Monocline fold
A monocline is a simple bend in the rock layers so that they are no longer horizontal.