Figure 18, Text Version. Theoretical cross section and how the surface calculations would be done from 5,000 years before present to present day. This particular example is from 2,000 years before present. At 5,000 years the shoreline began prograding, so dune ridge age information had to be incorporated into the surface generation technique. Also, the differentiation between shelf and bay deposits is no longer delineated strictly by the intersection of the sea level curve with the ravinement surface. The position of the prograding beaches has a greater influence on the boundary between shelf and bay deposits.

6/7^th of the sediment thickness from the ravinement surface to the present day surface is deposited in the shelf where this amount does not cause the new surface to be shallower than 1.5 meter depth. In those places simply fill with sediment to the 1.5 meter isobath.

Beach bounds are determined by dune ridge age information (Percy, 2000). Beaches are filled from the lowstand surface to the present day DEM elevation.

Bays fill to the 1.5 meter isobath. This assumes that sedimentation keeps pace with sea level rise.

Image also shows lowstand surface, ravinement surface, shelf deposits, beach deposits, and bay deposits.