Sedimentologic Architecture of the Shoreface Prism, Relationship to Profile Dynamics, and Relevance to Engineering Concerns: Duck, North Carolina

This report examines of the relationship between subsurface sediment distribution, profile dynamics, and nearshore processes. Coastal engineers involved with the design of hard structures and the placement of sand for beach nourishment purposes necessarily make certain assumptions and utilize concepts involving profile shape (e.g., equilibrium-profile and nearshore profile closure) and sediment transfer (e.g., onshore-offshore transport). However, much is still unknown concerning the actual nature of bed conditions and sediment transport across the shoreface, especially as it relates to the geometry-based concepts of erosional lower limits, profile closeout, and profile equilibrium. Related to this is the question involving grain size and the amount of sand transported offshore beyond the depth of profile closure during major storm events. In addition, much is still unknown concerning bar morphodynamics, associated fluid processes, and sediment transfer within the nearshore. Study of the internal physical properties of the nearshore zone can provide new and significant information concerning the above topics.