The cause of dune building at high sea levels
Reduced protection of the nearshore environment would be a consequence of the deepening waters associated with a marine transgression. The penetration of larger waves onto the Bermuda platform would doubtless cause the mobilization of transgressive lagoonal sediments and would result in an increased rate of coastal erosion. Testifying to the latter effect is the ruinous state of many sizable dunes at the present coast caused by a recent, Holocene transgression.

The large volume of limestone sand mobilized during a transgression would inevitably become a source for the development of extensive beaches. As sea level reaches its peak and the subsequent regression sets in, these beaches would, in turn, become ideal sites for dune building.