Erosional channels on the shoreface of Nauset Beach, Cape Cod, Massachusetts

Abstract

Many channels (1 to 3 m relief) are located offshore of Nauset Beach, Cape Cod, Massachusetts, in water 4 to 18 m deep. The channels are oblique to the shoreline, are spaced approximately 260 m apart, and deepen seaward. The southern flank of each channel is rippled whereas the northern flank and interchannel areas are smooth. The origin of the channels is unknown. They probably formed by erosion of the shoreface, perhaps by ripcurrent circulation during storm conditions or by rip-current circulation under quiet conditions. The channels may control current flow and thereby maintain themselves even though formative conditions may no longer exist.