Ridge Stratigraphy

Beach ridges are relict foredunes that form from eolian deposition above the high-tide line where vegetation baffles the wind and traps sand, resulting in foredune features that parallel the coast (Hesp, 1984). Given a positive sediment budget, the coast may prograde by accretion of sediment in the foreshore and on the beach. As the beach expands, pioneer vegetation can extend seaward, eventually trapping sediment and beginning growth of a new foredune. A record of sea level at the time of beach ridge formation may be preserved in the coarse beach sediment deposited in the swash zone adjacent to the ridge. If this can be identified and dated, a record of sea level through time as the beach ridge plain grew can be documented (Dott and Mickelson, 1995).