The glacially deranged karst topography of the Helderberg Plateau, central New York, contains glaciolacustrine lithofacies deposited at the end of the Wisconsin glaciation. Eight pre-glacial caves (Barrack Zourie Cave, McFail's Cave, Howe Caverns, Secret Caverns, Bensons Cave, Gage Caverns, Schoharie Caverns, and Caboose Cave), containing a unique sediment section, are located within the footprint of Glacial Lake Schoharie, Schoharie County. The lithofacies consist of three individual facies,

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... ratigraphically uniform, with the middle facies in sharp contact with the facies directly above and below. This assemblage displays a similar stratigraphic sequence from bottom to top: tan/white to light-grey, very thinly bedded, silts and clays, rich in calcite, overlain by poorly sorted, matrix-supported gravels, in turn overlain by darkbrown very thinly bedded silts and clays. A post-glacial cave within the lake's footprint (Westfall Spring Cave) and a nearby pre-glacial cave outside the footprint (Knox Cave) were found to lack these lithofacies. The tan/white to light-grey sediment facies is interpreted to be a glacial rock flour deposited under stagnant lake conditions that limited fine-grained calcite particle dissolution. The overlying gravel facies were emplaced during lake termination and reestablishment of turbulent epigenic flow in the eight stream caves. The more recent dark-brown facies is perhaps soil-loss deposition following European settlement. Initial interpretations hypothesized that the deposits were laid down under ice-cover conditions, but similar deposits were not found in other glaciated cave settings in New York. The results presented here explain why the unusual tan/white and light-grey glaciolacustrine facies are not found in other caves in the glaciated central New York region, as those areas were not subject to inundation by glacial lake water.