ABSTRACT

The veneer of shell material on a beach berm represents a lag deposit created by aeolian deflation processes. This feature, termed an aeolian shell pavement, is analogous to the stone pavements of desert regions. The presence of the pavement protects both the beach berm and the foredunes from marine erosion, although it also restricts sediment availability to the dunes. During the intervals when the pavement is exposed, the roughness characteristics of air flow across the beach are altered, causing changes in the movement of sediment. The pavement also acts as a sand reservoir during relatively calm periods. Monitoring of weekly changes in extent of the pavement suggests that it is a persistent feature except during extreme storms, when it is liable to be buried, reworked or eroded. R establishment of the feature following storms is rapid, between 14 and 40 days in these examples. The existence of the feature has an important bearing on shoreline progradation.