fault scarp

A steep slope or cliff created by vertical displacement along a fault during an earthquake — one side of the fracture lifted or dropped relative to the other, leaving a fresh, raw face of exposed earth or rock. Fault scarps are the most dramatic visible evidence of seismic activity. In the Basin and Range of Nevada and Utah, the mountain fronts are fault scarps — the valleys dropped while the ranges rose, and the abrupt transition between flat basin and steep mountain is the fault's signature.