1. How Deep is Wave Ravinement: Moving Beyond the Break-In-Slope Proxy
Antonio B. Rodriguez, Institute of Marine Sciences, University of North Carolina at Chapel Hill, Morehead City, NC 28557
The depth of wave ravinement, which is the depth where erosional wave processes can no longer rework coastal lithosomes, is assumed to be equal to the depth of the shoreline break-in-slope; however, this has never been rigorously examined. We are testing this by directly measuring ravinement depth in a variety of estuarine focus areas along the Newport River Estuary and Bogue Sound, North Carolina, and comparing these direct measurements to shoreline break-in-slope depths. Subsurface geology was variable between sites. Preliminary data show that variability in underlying lithology (clay versus sand) has little effect on ravinement depth, but may have a large effect on the rate of ravinement.
Direct measurements of the shoreline break-in-slope depth
same core
Ravinement surface identified in a core transect.
Schematic diagram showing ravinement along an estuarine shoreline. Sediment removed is transported landward and deposited onto the adjacent marsh surface, and is also transported bayward and deposited above the ravinement surface.