EXAMINING GLACIAL LAKE ALBANY IN SARATOGA SPRINGS, NY, USING VARVE METHODOLOGIES

Glacial Lake Albany was a proglacial lake that existed in Eastern New York’s Hudson Valley between 15,000 and 12,600 calendar years before the present. The lake extended north-to-south from the present-day Glens Falls area to Rhinebeck or Rondout, NY. Minimal research concerning the climate of the northernmost reaches of Glacial Lake Albany has occurred. Glacial Lake Albany’s varves serve as proxies for the lake’s paleoclimate as functions of meltwater, sediment input, and seasonality. Cross sections of varve cores from Greenfield, NY, depict Glacial Lake Albany’s sediment-deposition cycles and thus elucidate Glacial Lake Albany’s climate. Dark, clay-rich layers indicate low-energy, low-oxygen winter environments. In contrast, light, sand-rich layers suggest high-energy summer settings and reflect high-meltwater environments. While the layers’ colors generally span shades of brown, clay-rich red layers also appear in the varve samples; those layers correlate predominantly to winter conditions, and thus suggest a unique change in depositional conditions during many winter (and some summer) seasons. From winter to summer layers, varying layer thicknesses indicate seasonal duration and/or energy intensity during a given depositional sequence. In comparison to summer-layer thicknesses, on average, winter layers’ more varied and greater thicknesses suggest that winter conditions, at times, functioned independently of summer conditions; moreover, that winters fostered extensive storm events. The varves thus function as a geologic record of recent Quaternary history and may clarify uncertainties in glacial New York’s climate