An Application of OSL Dating to Test the Perched-dune Model on Coastal Dunes at Arcadia, Michigan

Results indicate that the Arcadia dunes mantle ∼ 90 m of glacial sediment. Formed near the top of this deposit is a well developed paleosol that was buried by eolian sand ∼ 4.5 ka. Episodes of dune growth subsequently occurred at ∼ 3.5, 1.7, 1.0, 0.9, 0.7, 0.4 and 0.3 ka. Most of these episodes generally coincided with estimated high lake levels. One major period of dune construction clearly occurred during a lake regression, however, suggesting that perched dunes may also be supplied with sand during low lake phases. Although some synchrony in dune growth was observed across the field, some periods were asynchronous, suggesting local factors may play a role in sand deposition.