An individual fault surface generally is not a flat or smoothly curved surface but instead may have fault ramps connecting segments of the fault (Figure 4.25 A). A frontal ramp is oriented such that its intersection with the main fault surface is approximately perpendicular to the displacement direction on the fault. On the strike-slip faults, frontal ramps are called jogs or bends. A lateral ramp is oriented such that is intersection with the main fault surface is oblique or parallel to the displacement direction on the fault. If parallel, it is also a step or sidewall ramp; otherwise, it is an oblique ramp.