Evidence of An Ice-Dammed Lake and Laurentide Readvance Upper Susquehanna Valley, New York State

Landforms and well logs document a system of ice-contact proglacial lakes in the upper Susquehanna valley during Laurentide Ice Sheet retreat from Appalachian Plateau, central New York State.  Recessional moraines formed dams for all lakes, except newly revealed “Ancestral Goodyear Lake” retained behind an ephemeral ice dam stranded at Colliersville.  A prominent dead-ice sink currently occupies floor site
 
 Ancestral Lake held stable lake level 1360 feet as represented by thick sediments perched water on wall above Lake.  deltaic terrace 1250 same vicinity marks second, lower strand.   In addition, adjacent Portlandville Moraine contain bound below material deposits thus demonstrating readvance that subsequently dammed to form Glacial Milford part System.