DART excavation data

Excavation and probe installation was carried out on the four DART sites, namely Quarry Field and Cherry Copse, Harnhill and the pasture field on gravel and clay field at Diddington between 11 April and 23 August 2011. This fieldwork followed on from previous magnetometer and borehole surveys of all four DART sample sites undertaken in January to March 2011. A final excavation was conducted on Diddington Pasture Field in June 2013. This collection contains the contexts, plans, sections and other excavation related data. This data is recreated in the integrated database.

Data and Resources

Additional Info

Field Value
Author Keith Wilkinson
Maintainer Anthony Beck
resource.abstract Excavation and probe installation was carried out on the four DART sites, namely Quarry Field and Cherry Copse, Harnhill and the pasture field on gravel and clay field at Diddington between 11 April and 23 August 2011. This fieldwork followed on from previous magnetometer and borehole surveys of all four DART sample sites undertaken in January to March 2011. A final excavation was conducted on Diddington Pasture Field in June 2013. This collection contains the contexts, plans, sections and other excavation related data. This data is recreated in the integrated database.
resource.accessConstraints None
resource.bibliographicCitation @data{dart_excavation_data, doi = {not allocated}, url = {http://dartportal.leeds.ac.uk/dataset/dart_excavation_data}, author = {Keith Wilkinson}, publisher = {The DART project, School of Computing, University of Leeds}, title = {DART excavation data}, year = {2013}, note = {DART is a Science and Heritage project funded by AHRC and EPSRC. Further DART data and details can be found at http://dartportal.leeds.ac.uk}}
resource.completeness Complete
resource.consistency Consistent data structure, attribution and relationships.
resource.contributor.email a.r.beck@leeds.ac.uk,dxb043@bham.ac.uk,r.j.fry@student.bradford.ac.uk,LEP001@bham.ac.uk,scds@leeds.ac.uk,Keith.Wilkinson@winchester.ac.uk
resource.contributor.name Anthony Beck,Dan Boddice,Robert Fry,Laura Pring,David Stott,Keith Wilkinson
resource.contributor.orcID http://orcid.org/0000-0002-2991-811X,http://orcid.org/0000-0002-3738-2327,http://orcid.org/0000-0002-9711-1131,http://orcid.org/0000-0002-5363-7959,http://orcid.org/0000-0003-3042-2813,http://orcid.org/0000-0002-3996-0696
resource.creation.endDateTime 2013
resource.creation.startDateTime 2011
resource.creation.status Complete
resource.creator.email Keith.Wilkinson@winchester.ac.uk
resource.creator.name Keith Wilkinson
resource.creator.orcID http://orcid.org/0000-0002-3996-0696
resource.custodian.email a.r.beck@leeds.ac.uk
resource.custodian.name Anthony Beck
resource.custodian.orcID http://orcid.org/0000-0002-2991-811X
resource.description Excavation and probe installation was carried out on the four DART sites, namely Quarry Field and Cherry Copse, Harnhill and the pasture field on gravel and clay field at Diddington between 11 April and 23 August 2011. This fieldwork followed on from previous magnetometer and borehole surveys of all four DART sample sites undertaken in January to March 2011. Preliminaries to excavation and probe installation Magnetometer surveys were conducted by Rob Fry and David Stott at three sites in Harnhill on 24-27 January 2011 and four locations at Diddington on 7-10 March 2011. On the basis of the results of these surveys, presumed archaeological features were selected on the four sites for further investigation by borehole drilling. Borehole surveys were subsequently carried out by Keith Wilkinson and Nick Watson (an ARCA consultancy technician) at Harnhill on 3 March and at Diddington on 9-10 March. These latter studies suggested that the ditches selected for study at Harnhill (both in Quarry Field and Cherry Copse) were of c 0.6m depth, while that on the clay field at Diddington was c 1m deep. However, the ditch identified for study on the pasture/gravel field at Diddington proved to have fills that were inseparable from the background soil profile, while the feature also appeared as a notable depression in the present field surface. Consequently the decision was made to target a second ditch on the Diddington pasture field and a further borehole profile was drilled by Keith Wilkinson, Nick Watson and Natsuhito Fuji (an undergraduate student at the University of Winchester) on 16 March 2011. This latter demonstrated that the newly selected ditch was c 1m deep and therefore suitable for probe installation. During the latter visit to Diddington the locations of all boreholes were accurately surveyed using a Leica System 1200 dGPS. Trench locations were planned on the basis of the geophysics and borehole results. Trenches on the two clay sites (i.e. Quarry Field, Harnhill and the clay field at Diddington) are L-shaped, the base of the L cutting tangentially across the ditch and the longest axis passing along the centre of the ditch. Trenches on the well-drained sites (Cherry Copse, Harnhill and the pasture field at Diddington) are straight 8m long slots that cut tangentially across the targeted archaeological feature. Excavation and probe installation Diddington Excavations at Diddington Clay field were carried out between 22 and 24 August 2011 by David Stott, Rob Fry, Ant Beck, Dan Boddice and Keith Wilkinson. As with the initial pasture field trench, a topographic survey was initially conducted of the 10x10m area encompassed by the trench using the Leica System 1200 RTK GPS (on 22 August 2011 by Keith Wilkinson) and the trench was then surveyed in with the same device using a control point in the north-east corner of the field that had been established in February 2011. However, on 23 August a decision was later made to move the trench to a location east of the surveyed 10x10m area. A mini digger manned by a driver from Lattenbury Services dug the 8m long by 1.2m wide excavation trench that bisected the ditch. Mechanical excavation continued through topsoil (Context 1) and subsoil (Context 2) (both developed in weathered Boulder clay) to a depth of 0.6m in the central and southern part of the trenches at which point archaeological deposits were encountered. In situ Boulder clay (Context 6) was encountered at the same depth in the northern end of the trench, but a further 0.6m were removed to provide a section for sampling and installation of TDR/temperature probes. The archaeological deposits in the central and southern part of the trench were hand-excavated by Rob Fry, David Stott and Keith Wilkinson and the moderate quantities of Romano-British/Iron Age pottery were bagged by context and retained for later study. The ditch in the centre of the trench (Context [3] was cut from 0.6m depth and penetrated 0.4m into the Boulder clay. It was filled by Context 5, a dark, humic primary fill containing moderate to frequent fine ceramic fragments and Context 4, a tertiary fill of redeposited Boulder clay that is interpreted as a deliberate deposit to level the ditch with the ground surface. Two pits (Context [7] and [10] were found in the southern part of the trench and were filled with three contexts (8 secondary fill 9 and 11 primary fills) containing frequent Romano-British ceramics (including Samian Ware). Once the west and eastern sections had been drawn by David Stott and Rob Fry, Dan Boddice inserted TDR and temperature probes into the eastern section. A total of 10 monolith samples were also taken from the deposits infilling ditch [3] and overlying strata and from topsoil, subsoil and Boulder clay in the northern end of the trench. The monoliths provide duplicate samples for analysis at the Universities of Birmingham and Winchester. Meanwhile Vincent van Walt installed two further TDR probes in 75mm diameter boreholes approximately 2m east of the excavated trench. One probe was positioned so as to pass through the ditch sediments, while the other was located outside the ditch. Finally, the TDR probes (both those installed by Dan Boddice and Vincent van Walt), the trench corners, the tops of monolith samples and the datum nails used for drawing the trench section, were surveyed with respect to OS NGR and OD using the System 1200 GPS. The fieldwork at Diddington (all phases) progressed more smoothly than at Harnhill, largely because of the greater time that was available. As a result recording was of a better quality and both probe installation and backfilling proved to be less stressful activities. However, there are problems with the GPS data from Clay field. The radio connection between the base station and the rover broke in the August 2011 season, meaning that the base station had to be moved within Bluetooth range of the rover. Post-processing of the resultant data is still to be completed RINEX data from a permanent ground station need to be obtained. GPS data collected from Clay field in June 2013 were not logged as raw data and cannot presently be post-processed. A solution is currently being sought from OptiCal Ltd (the organisation who had serviced the GPS in the week preceding fieldwork). Excavation and probe installation in the pasture field on gravel took place at Diddington from 6-8 June 2011, the field team comprising Laura Pring, Dan Boddice, Rob Fry, David Stott, Ant Beck and for 7-8 June, Keith Wilkinson. The trench location had been laid out by Keith Wilkinson using the dGPS on 13 May 2011, during which visit a topographic survey at 0.5m resolution was also carried out of a 10 x 10m area around the trench. A conventional, wheeled JCB mechanical excavator was initially used to remove the topsoil (context 1) along the length of the trench and a compact silt/clay mixed with rounded and sub-rounded flint pebbles was revealed (context 2). This deposit is likely to be the result of mixing (by the plough) of floodplain alluvium and gravel from the underlying terrace. Context 2 was also removed by the JCB to reveal a ditch in the centre of the trench. The ditch was then manually excavated on a context by context basis (contexts 3-5) by David Stott and Rob Fry, with finds from each context being separately bagged. The latter comprise ceramic sherds of up to boulder size and of probable prehistoric age (The pottery has been taken to Winchester and a report on these artefacts will be commissioned from an appropriate specialist once excavations at the clay field, Diddington have been completed), and animal bone. Meanwhile the JCB was used to excavate a depression into which Laura Pring and Dan Boddice placed the TDR box and weather station. Finally the JCB excavated a 6m long section of the trench down to 1.2m depth exposing Pleistocene gravels (contexts 6 and 7) in locations outside the ditch. Excavation of the pit for the TDR box and weather station had partially truncated one of the long sections of the trench, but the remaining part together with the other long section was photographed and then drawn by Keith Wilkinson at a scale of 1:10 on 7 June. Two series of monolith tins were then taken through the ditch sediments on the south side of the trench (a total of four tins) and through the non-ditch stratigraphy on the north side (two tins). The JCB had been off-hired for 7 June. TDR and temperature probes were installed by Laura Pring and Dan Boddice on 8 June. Eight probes of each kind were placed in the ditch fills and eight on the outside. Once the probes had been emplaced they were marked on the section drawing and surveyed in with the dGPS. The dGPS was also used to survey in the reference nails used in the section drawings, the position of two 0.5m-long steel pipes inserted in the trench base on 6 June (for calibrating future GPR surveys) and the real corners of the trench (the trench had been planned with a width of 1m, but the bucket of the JCB that was used to excavate the trench was 1.2m wide). The trench was then backfilled both manually and with the aid of a mini-excavator (that had been hired instead of the JCB at the suggestion of Lattenbury Service, driver [Mark]). An attempt was made by Keith Wilkinson and Rob Fry to take core samples from outside the ditch, but while the core sampler penetrated the topsoil, compacted gravel/silt/clay and the gravel of the underlying terrace, it proved very difficult to extract. Further attempts to obtain core samples were thus abandoned. However, 12 locations for future boreholes were surveyed with the dGPS and marked with red surveyor, pegs along the course of the sampled ditch. Quinton Carroll (Cambridgeshire, County Archaeologist visited the site on 8 June to view the works and the finds that had been recovered. He requested that DART produce a report on the results of the fieldwork for the county, HER. The fieldwork at Diddington progressed more smoothly than at Harnhill, largely because of the greater time that was available. As a result recording was of a better quality and both probe installation and backfilling proved to be less stressful activities. Excavation and probe installation Harnhill Excavation and probe installation at Harnhill took place between 11 and 16 April 2011. Rob Fry, David Stott, Natsuhito Fujo and Keith Wilkinson manually removed topsoil from both the Quarry Field and Cherry Copse trenches on the 11-12 April and then excavated the fills of ditches that were revealed beneath. The latter procedure was carried out using standard archaeological procedures and on a context by context basis. The excavation at Cherry Copse demonstrated that the selected ditch was 1m deep, cut through weathered limestone of the Cornbrash Formation and was infilled by a poorly sorted mixture of red brown silt/clay and limestone boulders and pebbles. Finds from the ditch all dated to the last 100-150 years and included glass fragments and a tin can. It can therefore be concluded that the ditch is a modern feature. In contrast to the relatively simple stratigraphy at Cherry Copse, the excavations at Quarry Field revealed a more complex story. The sampled ditch was cut through clay strata of the Forest Marble Formation to a depth of 1m, while the infilling sediments largely comprised reworked clay, albeit modified by soil forming processes near the surface. However, two ceramic drainage pipes dating from within the last 150 years were found at the base of the ditch. On visiting the excavation on 12 April Tony Norris (RAC) said that he did not know about the pipes, but gave us permission to cut through them. While the excavations were proceeding Laura Pring and Dan Boddice assembled three TDR boxes and two weather stations at the RAC farm facility in Harnhill village, while Natsuhito Fuji carried out a dGPS survey of a 15 x 15m area around the Quarry Field and 10 x 10m around the Cherry Copse trenches to produce models of surface topography. On 13 April a tracked mechanical excavator was used to excavate out first the Quarry Field and then the Cherry Copse trenches to 1m depth. On the Quarry Field site this procedure resulted in the discovery of a concrete-lined drain cutting at right angles through the dual ceramic pipe drains in the body of the L. The former was capped by concrete paving, which when removed, revealed that the drain was still active. A spread of gravel was found to the immediate south-west of the concrete drain that had also been placed in a cut through the ceramic pipes. The fact that the drain was still active and the truncation caused to the stratigraphy by the insertion of this feature and the gravel led to the decision to discontinue work in the body of the L and focus all attention of the north-east part of the trench (Figure 1). Both long sections of the northern arm of the L were drawn at a scale of 1:10 by David Stott and then photographed, and then the infilling ditch and non-ditch sediments were sampled in duplicate series (one each for the University of Birmingham [for geotechnical purposes] and University of Winchester [geoarchaeology]) of monolith tins (6 monolith tins were taken in total) (Figure 3). The monolith tins were photographed in situ and then extracted. Laura Pring, Dan Boddice, Nicole Metje, David Chapman and Giulio Curioni then commenced the TDR and weather station installation. Sixteen TDR and temperature probes were placed in the ditch sediments and sixteen outside. The dGPS was meanwhile used to collect positional data for the reference nails used in the section drawings, the tops and bases of the monoliths and the corners of select experimental growing areas used by the RAC in their crop trials (Unfortunately the wrong reference information was input into the base station, meaning that the dGPS data collected at Quarry Field on the morning of 13 April will need to be re-processed). Once the mechanical excavator had excavated a depression in which the TDR boxes and weather station would sit at Quarry Field, it was moved to Cherry Copse to excavate the transect trench to 1m depth (Figure 4). The cleaned faces were photographed and then David Stott and Rob Fry drew the exposed long sections at a scale of 1:10. A duplicate series of monolith samples were taken from the Cherry Copse section on 14 April by David Stott and Rob Fry (aided by the mechanical excavator) and a total of four tins collected. The mechanical excavator was then used to excavate a depression to house one TDR box and a weather station, after which Laura Pring, Dan Boddice and Giulio Curioni installed eight TDR and temperature probes in the sediment sequence infilling the ditch and eight outside2. Laura Pring, Dan Boddice and Giulio Curioni spent the period from the afternoon of 14 April to 15 April infilling (with the aid of the mechanical excavator) and compacting the excavation trenches. Several valuable lessons were learnt as a result of work at Harnhill, namely: 1. We had not allowed enough time for probe installation and backfilling. 2. The mechanical excavator had originally be hired for one day, but in practice three days of machine time were required. 3. Carrying out two excavations/installations simultaneously/in quick succession and within a single week led to some comprises in recording and was found to be overly stressful for those conducting the fieldwork. Keith Wilkinson, Natsuhito Fuji, Nicole Metje and David Chapman had had to leave Harnhill on the evening of 13 April. Excavation and probe installation Diddington A second trench on the Diddington pasture field was excavated on 12 June 2013 to examine and ground truth anomalies revealed in ERT surveys carried out by Rob Fry in 2011 and 2013. The field team comprised Rob Fry, David Stott, Dan Boddice, Ant Beck, David Jordan and Keith Wilkinson, while the mechanical excavator was operated by Mark of Lattenbury Services. The 2013 trench was located 7.5m north-west of the first and measured 7.6m long by 1.2m wide. As with the first trench, the second was surveyed in to OS NGR and OD using a Leica System 1200 RKT GPS (using a point with known coordinates established by David Stott/Rob Fry during their surveys of the field in 2011-2012). A final ERT survey was then carried out of single transect corresponding to the trench before excavation commenced. A wheeled JCB mechanical excavator excavated the trench using a 1.2m wide, toothless ditching bucket. Initially excavation was to 1.2m depth, but only the top of the ditch to be sampled (Context [10]) was encountered at this depth. Therefore extensions were made to the side of the trench, enabling the central portion to be excavated down to 1.6m below ground level (BGL) and thereby exposing the entire ditch sequence. Unfortunately the water table lay at around 1.4m BGL, meaning that water ingress hampered investigation. On completion of the mechanical excavation, the southern section (north facing) was photographed and drawn at a scale of 1:10 by Rob Fry and David Stott. Meanwhile Dan Boddice collected moisture/permittivity data from the north section using a portable TDR device, while David Jordan (University of Mainz) collected samples from which to make thin sections and for laboratory measurements of p and E against water content using ER and TDR equipment. Finally three monolith samples and 11 (sample numbers 30-40) bulk samples were collected by David Stott, Rob Fry and Keith Wilkinson from the north section for laboratory measurement of grain size, magnetic susceptibility and organic carbon by loss-on-ignition measurement at the University of Winchester. The location of the samples was marked on the section drawing, while the System 1200 GPS was used to locate the nails suspending the datum in the section drawing, the location of the in situ TDR measurements, the top of the monolith samples and the samples collected by David Jordan. The sequence exposed in the July 2013 excavation trench comprised 11 contexts (two of which are ditch cuts [10] and [11]) The ditch that was the focus for the excavation [11], was cut from 0.6m BGL and extended downwards another 0.8m through Pleistocene sand (Context 5) and gravel (Contexts 4 and 6) strata. The two fills (Contexts 7 and the fill of a later recut, Context 9) both appear to be deliberate given their homogeneity and poor sorting. A second ditch [10] was also cut from 0.6m BGL and also contained a deliberately deposited infill (Context 3). Both ditches are overlain by floodplain alluvium in which soil formation has taken place (Context 2 is a B horizon and Context 1 the A horizon). Away from the two ditches the floodplain alluvium has an unconformable contact with the sands and gravels at 0.5-0.6m BGL. Unlike the June 2011 excavation, artefacts were noted neither in the floodplain alluvium nor in the ditch fills. Acknowledgements All those involved in the fieldwork between January and June 2011 would like to express their particular thanks to Tom Overbury and Tony Norris at the RAC and Vicky Dickens and Richard of Thornhill Estates, Diddington. We would also like to thank the machine drivers from Bison Hire (Harnhill) and Lattenbury Services (Diddington) for the care they displayed in excavating our trenches.
resource.distribution.technique Download only
resource.edition 1
resource.fileFormat .txt, .svg, .shp, .zip
resource.funder Science and Heritage Programme, Arts and Humanities Research Council, Engineering and Physical Sciences Research Council
resource.instructionalMethod None - this is a collection
resource.keywords Contexts, Plans, Finds, Sections
resource.language eng
resource.license odc-by
resource.license.typeURL http://opendatacommons.org/licenses/by/
resource.lineage None: this is raw data
resource.localURI http://dartportal.leeds.ac.uk/storage/f/dart_excavation_data
resource.metadata.creator.email Keith.Wilkinson@winchester.ac.uk
resource.metadata.creator.name Keith Wilkinson
resource.metadata.creator.orcID http://orcid.org/0000-0002-3996-0696
resource.metadata.language eng
resource.processingStage Complete
resource.publisher School of Computing, University of Leeds
resource.purpose multi-temporal heritage detection
resource.relatedResources DartProjectOverview
resource.repositoryName http://dartportal.leeds.ac.uk/
resource.reuseConstraints No conditions apply for reuse (remix it, publish it, share it, commercialise it, sell it etc.) except attribution (see resource.bibliographicCitation)
resource.reusePotential archaeology, environment, heritage, soil science, farming, ecology, geography, earth science
resource.topic geoscientificInformation, environment, heritage, farming, climatology/Meteorology/Atmosphere, imageryBaseMapsEarthCover, society, structure
resource.type Dataset collection
resource.type.specific Text, Vector, GIS
resource.updateFrequency not planned
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spatial-text United Kingdom
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spatial.boundingBox.WGS84.westLongitude -1.907587
spatial.defaultReferenceSystem OSGB36
spatial.driftGeology DDCF: http://www.bgs.ac.uk/lexicon/lexicon.cfm?pub=TILMP, DDPF: http://www.bgs.ac.uk/Lexicon/lexicon.cfm?pub=T1T2, HHCC: Clay: no superficial drift geology, HHQF: no superficial drift geology
spatial.landuse Permanent pasture: DDPF, Arable: DDCF, HHCF, HHQF
spatial.ordnanceSurveyPlaceName Harnhill (http://data.ordnancesurvey.co.uk/id/50kGazetteer/109734) and Diddington (http://data.ordnancesurvey.co.uk/id/50kGazetteer/72767)
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spatial.solidGeology DDCF and DDPF: http://www.bgs.ac.uk/lexicon/lexicon.cfm?pub=OXC, HHCC: http://www.bgs.ac.uk/lexicon/lexicon.cfm?pub=CB, HHQF: http://www.bgs.ac.uk/lexicon/lexicon.cfm?pub=SI
temporal.rangeDescribedByDataDateTime.end Now
temporal.rangeDescribedByDataDateTime.start Iron Age
temporal.resource.availableDate 2013-07-15
title.alternative dart_excavation_data
title.pattern Where appropriate each resource has been named with the following pattern: DART_<3 character sensor/collection name>_<spatial location>_<StartDateTime YYYYMMDD with optional HHMM>_<endDateTime YYYYMMDD with optional HHMM>_<stage PRO or RAW to refer to processed or raw data>_<other stuff>.<suffix>. Hence, the file DART_T3P_DDCF_20110823_20130106_PRO.csv refers to DART data collected using the T3P Imko soil moisture probes at Diddington Clay Field between 23rd August 2011 and 6th January 2013 which has been processed and is available in a comma separated text format.