Geomorphic
History of Dunes at Petoskey State Park, Petoskey,
Michigan
Lepczvk, Xiomara C. and Arbogast, Alan F.
Coastal dune fields commonly occur
along the shoreline of Lake Michigan. This
study focuses on the geomorphic history of dunes at Petoskey State Park
in northern lower Michigan. Results from this study
revealed that 5 distinctive geomorphic units occur in the park: a lake terrace,
parabolic dunes, linear and incipient parabolic dunes, and active dunes.
Samples for optically stimulated luminescence (OSL) and radiocarbon dating were
collected throughout the park and suggested that eolian activity began around
4800 cal. yr B.P. and has continued until the present time. In general, the
dunes are progressively younger and smaller towards the shoreline. Intensive
shoreline progradation and significant vertical aggradation of sand dunes has
occurred at Petoskey State Park throughout the Middle and Late Holocene in
association with fluctuations of the level of Lake
Michigan.