Two types of structural framework are predominant on shallow seismic profiles recorded at the continental shelf edge off North Carolina between Cape Hatteras and Cape Fear. At least six prominent progradational sedimentary units, which are separated by disconformable surfaces, indicate that the continental shelf edge seaward of Cape Fear has been formed mainly by outbuilding. Uniformly thick parallel beds predominant north of Cape Fear are the result of relatively uniform upbuilding-outbuilding processes. Within this parallel bedded structure, a distinct erosional surface can be traced from the outer shelf to the upper continental slope, where it is truncated by another buried erosional surface.

Surface topographic features near the shelf break off North Carolina have been formed largely by erosional processes, although locally organic accretion may have occurred. Small terraces and ledges that are exposed or buried were eroded into the outer shelf and upper slope during pauses in the fluctuating sea levels of the Pleistocene and Holocene Epochs. Notches on the upper continental slope appear to have two origins: (1) erosional, i.e., the notch was carved by the Gulf Stream, and (2) erosional or nondepositional, i.e., the notch was formed between the exposed back slope of a terrace and the sedimentary wedge occurring on the terrace platform.