Geoarcheology Research Associates (GRA) was contracted to conduct geoarcheological investigations of buried landscapes on 2nd Avenue between E 92nd and E 99th Streets on the Upper East Side of Manhattan, NY.
Objectives were to assess the archaeological potential of the buried landscapes associated with a historically documented estuary and marsh and/or near shore environments beneath it. The project area was known as Hellgate Bay until it was infilled and urbanized in the late 19th century. Investigations consisted of extensive background historical and geomorphic research, field collection of five (5) cores systematically placed along the linear project corridor, and laboratory studies focused on stratigraphic interpretations, radiometric dating, and pollen, macrofossil and molluscan identifications in support of environmental reconstruction.
Stratigraphies of the primary cores were linked with an extensive collection of previously excavated geotechnical borings. The buried sequences revealed intact successions of bedrock, thin Pleistocene tills and deeper lacustrine deposits that are overlain by middle to late Holocene estuarine sediments. These borings register one of the only intact Late Quaternary sequences ever documented for Manhattan Island. Environmental studies of the Holocene deposits show that in the project area Hellgate Bay was a subaqueous mudflat. Accordingly the potential for preservation of archeological deposits is low. While no archeological materials were recovered this project produced a wealth of important information about pre-historic ecology and landscapes of New York City.