What style of faulting occurs when the Vertical Stress is greater than the horizontal stresses?

What style of faulting occurs when the Vertical Stress is greater than the horizontal stresses?

• A. Normal faulting
• B. Strike-slip faulting
• C. Reverse/Thrust faulting
• D. Oblique-slip faulting

Answer: (A)

When the vertical stress is larger than the horizontal stresses, the crust is under extension in the horizontal plane, so it tends to pull apart rather than shorten. This extensional regime leads to normal faulting, where the hanging wall slides downward relative to the footwall along a dipping fault plane. Normal faults are typical in areas of crustal thinning or rifting, where gravity and vertical loading drive downward movement along the fault. In contrast, strike-slip faults arise from horizontal shear with little vertical displacement, and reverse or thrust faults come from compression with the hanging wall moving upward. Oblique-slip faults combine dip-slip motion with a strike-slip component. So the scenario described best matches normal faulting.

When the vertical stress is larger than the horizontal stresses, the crust is under extension in the horizontal plane, so it tends to pull apart rather than shorten. This extensional regime leads to normal faulting, where the hanging wall slides downward relative to the footwall along a dipping fault plane. Normal faults are typical in areas of crustal thinning or rifting, where gravity and vertical loading drive downward movement along the fault. In contrast, strike-slip faults arise from horizontal shear with little vertical displacement, and reverse or thrust faults come from compression with the hanging wall moving upward. Oblique-slip faults combine dip-slip motion with a strike-slip component. So the scenario described best matches normal faulting.