What style of faulting occurs when horizontal stress in one direction exceeds the horizontal stress in the perpendicular direction?

What style of faulting occurs when horizontal stress in one direction exceeds the horizontal stress in the perpendicular direction?

• A. Normal faulting
• B. Reverse faulting
• C. Strike-Slip faulting
• D. Thrust faulting

Answer: (C)

When horizontal stresses are different in two perpendicular directions, rocks experience shear along vertical planes, causing blocks to slide past one another laterally. That lateral, side-by-side movement defines strike-slip faulting, with the fault plane usually near vertical and little vertical offset. This is driven by horizontal shear rather than vertical extension or vertical compression. For contrast, normal faults arise from extension and hanging-wall subsidence, while reverse and thrust faults come from compression that pushes the hanging wall up over the footwall; thrust is a low-angle version of reverse faulting. A classic example of strike-slip motion is the San Andreas Fault, where horizontal stresses drive sideways movement along a near-vertical fault.

When horizontal stresses are different in two perpendicular directions, rocks experience shear along vertical planes, causing blocks to slide past one another laterally. That lateral, side-by-side movement defines strike-slip faulting, with the fault plane usually near vertical and little vertical offset. This is driven by horizontal shear rather than vertical extension or vertical compression. For contrast, normal faults arise from extension and hanging-wall subsidence, while reverse and thrust faults come from compression that pushes the hanging wall up over the footwall; thrust is a low-angle version of reverse faulting. A classic example of strike-slip motion is the San Andreas Fault, where horizontal stresses drive sideways movement along a near-vertical fault.