| Popis: |
The slab was broken out and ground reduction undertaken by the contractors. Areas were excavated by machine by the contractors, and monitored by a member of staff from MOLA. On the south side of the site, rubble and infill was removed from around the early 19th century brick built dock and its 20th century concrete extension. North of the dock, within the footprint of the secant piled perimeter wall, the area was also subject to ground reduction. MOLA archaeologists monitored pile probing, ground reduction and UXO probing. Area locations were recorded in relation to ground plans provided by the contractor with archaeological features established where discovered and subsequently tied to the OS grid. A detailed geoarchaeological record was taken of two sections north of the dock wall. The upper deposits were hand excavated, with monolith tin samples taken through the sequence. A hand auger was used to reach the base of the sequence. Preliminary interpretation of the soil and sediment characteristics of the sediments has been made and an overview of the stratigraphy produced that will characterise the deposit sequence and identify soil / sediment processes. A Holocene sequence (mainly consisting of soft clays lying over peat and then sandy silt atop the Pleistocene gravel) was recorded and sampled in Trench 5 and also as part of the previous borehole assessment undertaken on the site. The basal organic sequence had been previously radiocarbon dated to the late Neolithic and mid Bronze Age. The sequence is overlain by apparent post medieval (likely Georgian) made ground related to dock construction. Sands and gravels encountered from -2.02m OD are part of the Shepperton gravel and rise towards the north east to the Taplow terrace. The overlying deposits provided a record of landscape change particularly through the late Neolithic and Bronze Age periods when a wooded marsh developed over the gravel floodplain, which had remained high and dry throughout the Mesolithic. Although no direct evidence was found on the site of human occupation, there was indirect evidence particularly through pollen assessment of woodland clearance and agricultural activity locally during this period and probably on the higher terrace to the north of the site. |
