| Abstract: |
The fieldwork comprised the excavation of three of the four trenches (numbers and dimensions), in the locations shown on the attached plan. All of the excavated trenches were moved due to a smaller available area. An unknown gas main was discovered on site, as such Trench 4 was not excavated due to the presence of a medium pressure gas main. Test Pit 3 was not excavated due to its location beyond the edge of the site, within the quarried area. These changes were made with the approval of Liz Dyson. Trenches were set out on OS National Grid (NGR) co-ordinates using Leica GPS and surveyed in accordance with CA Technical Manual 4 Survey Manual. Palaeolithic Methods The Palaeolithic evaluation was based on a combination of targeted deep test pits and examination of the base of trial trenches. The Palaeolithic test pit evaluation was originally intended to comprise seven test pits distributed across the site, TPs 1-7, with five test pits (TPs 1-5) in Area G, and two test pits (TPs 6-7) in Area F. These were positioned in order: (a) to avoid the footprint of the previous small quarry in Area G, (b) to target the margin of the colluvial infill of the dry valley network at the Site, (c) to avoid known services, and (d) to avoid excavation too close to the cliff-edge of Eastern Quarry. Once on site, TPs 2 and 5 in Area G were re-located to avoid a previously unrecorded medium pressure gas-main, and TP 3 was omitted as it was located beyond the current cliff-edge. Therefore, six test pits were dug, TPs 1-2 and 4-5 in Area G, and TPs 6-7 in Area F (Figure 3). 4.3 Full details of the test pit excavation methodology were provided in the Written Scheme of Investigation (Cotswold Archaeology 2018b). In summary, the location of each test pit was first scanned for live services by trained Cotswold Archaeology staff using CAT and Genny equipment in accordance with the Cotswold Archaeology Safe System of Work for avoiding underground services. Each test pit was excavated by a tracked 360º excavator equipped with a 2m-wide toothless grading bucket as far as possible, although a toothed bucket was used on occasion to penetrate into Chalk bedrock. Excavation took place under direction of the Palaeolithic specialist (Francis Wenban-Smith) and the CA Field Supervisor. Topsoil and subsoil were initially removed (and stored separately) under supervision of the CA supervisor, and a record photograph made of the top of natural deposits. No post-Palaeolithic features were encountered. 4.4 Each test pit was then taken down in horizontal spits of 5-10cm, respecting the interface between sedimentary units when unit changes were encountered, and monitoring for Palaeolithic remains and sediments with palaeo-environmental potential. The Palaeolithic specialist recorded and numbered the sequence of sedimentary units as excavation progressed further down, following standard descriptive practices. Test pits were entered at the maximum safe depth (usually c. 1.2m) to record the upper stratigraphy. Beyond this depth, recording took place without entering the trench. Excavation potentially went down to a maximum depth of c. 4m below the current ground surface, although stopped at a higher level when pre-Quaternary bedrock was indisputably identified or when the base of deposits with archaeological potential was reached. In practice, pre-Quaternary bedrock (Chalk) was reached in two test pits (TPs 6 and 7) which were excavated to depths of 2.50m and 2.60m respectively. Firm chalk diamict (deposit I - see Section 5.1), which typically grades down into Chalk bedrock, was reached in three test pits (TPs 1-2 and 5), which were excavated to depths of 1.35m, 2.50m and 2.65m respectively. And TP4 was dug to a depth of 2m, demonstrating c. 1.5m of chalky colluvium (deposit IIb - see Section 5.1). |
