Introduction
We were invited to evaluate the geoarchaeology of a site at West St, Bristol, 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 Triassic Mercia Mudstone and we found the soils on the site to be well drained, fine loamy typical brown earths. The site lay on an area of land that sloped gradually to the south overlooking the valley of the River Avon. At the time of our visit the site lay in an urbanised area of Bristol currently undergoing redevelopment.
A number of trenches had been dug across the site, and it was in these that we were able to examine deposits visible in the side and take samples for later analysis.
Findings
The samples we examined were both natural and archaeological, in one of them we saw that the lower half was a natural brown earth profile that had been truncated, above which, the upper half was a typical urban deposit of brown earth soils containing archaeological debris, all mixed up by biological activity.
Conclusions
From our investigations, we we able to tell the excavating archaeologists that the land surface predating the site has been truncated and mixed into a topsoil that dates from the 17th Century onwards. Unlike soils on the Avon floodplain, the parent materials from this soil are pre-quaternary in age and any further study is unlikely to be very informative.