Introduction
We were invited to evaluate the geoarchaeology of a site at King Alfreds School, Burnham on Sea, to help the excavating archaeologists, both in understanding the origins of the deposits and in assessing the archaeological potential of the site.
Background
The bedrock of the area was known to be the Lower Lias of the Lower Jurassic, and we found the soils to be alluvial gley soils, which were deep, stoneless and formed on estuarine alluvium. The site lay in an area of flat land within the town of Burnham on Sea, and the permanently high water table is controlled by pumped drainage through ditches and sea defences. At the time of our visit the site was a part of the school playing fields.
Trenches were dug across the site in which deposits were examined and samples were taken for later analysis.
Findings
The samples examined were silty alluvial clay's overlain by a thin dark layer which contained evidence of human activity, this in turn was buried by further estuarine alluvial sediments. The alluvial deposits belong to the Upper Wentlooge formation, and the dark layer was a well developed granular soil that contained Roman artefacts. The alluvial sediments above this Roman soil up to the modern ground surface, suggest a changing sea level.
Conclusions
From our investigations, we were able to tell the excavating archaeologists that the buried Roman soil indicates active management of the landscape during that period, with a change or end to flood management towards, or at the end of the Roman period within this part of Somerset, with a return to alluvial deposition.