In a normal fault, the hanging wall moves down relative to the foot wall.

• A. Normal fault
• B. Lateral fault
• C. Reverse fault
• D. Thrust fault

Answer: (A)

In an extensional setting, the crust is pulled apart, and a normal fault forms. The block above the fault plane—the hanging wall—slides downward relative to the block below it, the footwall, due to gravity and the pulling apart of the crust. This downward movement creates the characteristic scarp and is common at divergent plate boundaries and rift zones.

In contrast, strike-slip or lateral faults move mainly horizontally, so there isn’t a significant up or down shift between hanging wall and footwall. In compression, the hanging wall moves up relative to the footwall, which is what happens in reverse faults; thrust faults are low-angle versions of those, with similar vertical motion but gentler dips. So the described movement—hanging wall going down relative to the footwall—fits a normal fault.