Geomorphic history of low-perched, transgressive dune complexes along the southeastern shore of Lake Michigan

A general geomorphic history of low-perched coastal dunes along southeastern Lake Michigan is developed by combining new chronological data from P.J. Hoffmaster and Warren Dunes State Parks (SP) with published data from Van Buren SP, Silver Lake SP and dunes near Holland, Michigan. Fragmentary evidence of dunes older than 6 ka has been almost obliterated by active dune growth since the mid-Holocene Nipissing transgression of ancestral lake Michigan. Aeolian activity continued during the drop from peak water levels similar to 4.7 ka resulting in broad fields of low dunes. Aeolian activity halted during a period of low lake levels but was renewed with the development of large parabolic dune during the Algoma high-water phase of Lake Michigan at similar to 3.2 ka. This was followed by reduced aeolian activity and development of the Holland Paleosol. Subsequent dune remobilization predates European settlement. High lake levels and land use practices cannot completely account for the pattern of aeolian activity which may be affected by changes in storm winds linked to changes in the paths of extratropical cyclones. Dune field morphology depends on the whether the shore is receding, prograding or stable. Simple lake-plain complexes form along receding shorelines where lakefront erosion exposes sediment to aeolian transport, leading to the preservation of a single set of large parabolic dunes migrating eastward with the shoreline. Compound lake-plain complexes form along stable or prograding shorelines. Here progressively younger dune ridges develop and blowouts migrate inland forming overlapping and nested parabolic dunes. (C) 2009 Elsevier B.V. All rights reserved.