Totten (1985) suggested that leaching of clay from weathering of shale clasts may explain the presence of some fine-grained sediment within the beach deposits. This lack of direct evidence has sometimes been explained by subsequent covering of those low outlets by a glacial readvance (Leverett and Taylor 1915). However, the lower-elevation outlets required to produce early lake-level low phases have not always been observed. Fine-grained sediments found on some beaches also have been described and used as evidence for submergence. In this case, a higher-elevation beach may be younger than a lower-elevation beach. The cyclic model was championed by Leverett and Taylor (1915), who noted that some beaches appeared "washed", implying submergence after deposition (i.e., beaches were transgressed over). The chronologies for ice-margin positions and for occupation of shorelines are based on little age data. Alternatively, from detailed sedimentologic and geomorphic work on a sequence of beaches in northeastern Ohio, Totten (1985) proposed a regular sequence of lake-level fall, also known as the 'episodic' model (gray line, Fig. Large vertical variability of lake level through the history of ancestral Lake Erie (ALE) is referred to here as the 'cyclic' model (black line, Fig. A common element in most reconstructions is cyclic lake levels that are controlled by fluctuating ice margins opening and closing poorly constrained and undated outlets. 1, 2) are known in general, but poorly understood in detail. The ages and evolution of proglacial lakes in the Lake Erie Basin (Figs. The results of OSL dating of sand dunes indicate a period of older activity (~14-15 ka) and confirmation of previous work that documented activity during the Younger Dryas cold period (~13-11.5 ka). Evidence supporting the Ypsilanti lowstand in the ancestral Lake Erie basin was not observed within two sequences of glacial lacustrine sediments. Thirteen (13) new OSL ages revealed a short time of approximately 1000 years (16.9-15.9 ka) for formation of the Maumee, Arkona and Whittlesey shorelines. The beaches showed no evidence of being flooded after deposition. Ground penetrating radar (GPR), electrical resistivity (ER), and optically stimulated luminescence (OSL) techniques were used to analyze beach and sand dune formations in the Wauseon area in northwest Ohio. While the general scheme of the retreat of the Late Wisconsinan glacier from the ancestral Lake Erie basin is understood, the sequence and timing of those movements that caused lake-level changes are not well documented.
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