SNN114167 - Elton 2, Warmington, Northamptonshire: Geoarchaeological Window Sampling

Ten window sample cores were put down in June 2018, located to augment data from eleven geotechnical boreholes sunk in 2015. In May/ June 2021 a further six window sample cores were sunk to the east as land within the site boundary became accessible. The revealed lithostratigraphy was used to construct a series of deposit models to aid in the geoarchaeological interpretation of the site. The investigation revealed a picture of mid-late Holocene floodplain development characterised by gradual channel abandonment and consolidation. Palaeotopography and drainage at the site is constrained by late Pleistocene sand and gravel deposits forming an elevated plateau or ‘island’ occupying a central position. Such islands are fairly common Nene Valley floodplain features and have been found to provide relatively stable land surfaces in the Early Holocene and a focus for Mesolithic activity. Hydrological change was initiated during the late Neolithic period with the silting of a former channel crossing the SE corner of the site commencing 4,819 calBP. Recovered macrofossil remains indicate an open landscape and slow-moving water body, suggesting gradual channel demise. This fits the wider picture of floodplain evolution recorded in the Nene Valley, which tends to be characterised by channel simplification since the Mid-Holocene. A further sequence of organic-rich deposits recorded c. 20m to the west of the current river channel accumulated between 4,816 and 2,186 calBP and may indicate the lateral migration of the primary channel or simply its contraction and deepening as a result of accelerated bank aggradation. Palynological assessment of the channel deposits indicates a contemporary open pastoral landscape, with local arable cultivation also suggested. Palaeoenvironmental macrofossils from the channel suggest a slow-moving channel set within an open environment, which is consistent with gradual channel abandonment. From the mid/late-Holocene and particularly from later historical periods, the sedimentary regime was dominated by overbank alluvial deposition, forming the main sedimentary unit of alluvial silts and clays that blanket the site. The close proximity of Neolithic and Bronze Age funerary remains suggests nearby settlement, most likely occupying elevated ground to the north and south, with the floodplain being utilised as seasonal pasture within a mixed agricultural regime. Four archaeological test pits were excavated through the topsoil/ subsoil and upper alluvium for the purpose of artefact recovery. The result of this exercise was negative