Well-developed simple, stabilized parabolic dunes that are oriented to the east and southeast form the inland portion of a dune complex that extends ~32 km east-west across the southern shoreline of Lake Michigan in northwest Indiana. To better understand shoreline evolution during the Nipissing and post-Nipissing phases of Lake Michigan, subsurface sedimentology and radiocarbon ages from interdunal wetlands are considered with optical ages from nearby dunes within the landward portion of this area known as the Tolleston Beach. In the east, the once expansive Great Marsh had developed during the lake-level fall from the Nipissing peak (~4500 years ago). Units...