What type of faulting is shown on the map running diagonally through the central portion?

• A. Normal fault
• B. Strike-slip fault
• C. Reverse fault
• D. Thrust fault

Answer: (C)

Faults are classified by the direction of slip between the blocks. A reverse fault forms under compression when the hanging-wall block moves up relative to the footwall. On a map, this shows as vertical or near-vertical uplift across the fault, with opposite sides offset by upward displacement of rocks on one side. The diagonal fault trace in the central area indicates that one side has been pushed up over the other, which is characteristic of reverse faulting. If the movement were mainly downward of the hanging wall, it would be a normal fault, and if the offset were primarily horizontal with little vertical displacement, it would be strike-slip. A thrust fault is a low-angle version of the same compressional regime, but the key sign here is the vertical uplift across the fault, pointing to a reverse fault.