Report on a fluxgate gradiometer and topographic survey carried out on various fields around Huttons Ambo (Low Hutton), North Yorkshire
on behalf of the Huttons Ambo History Group, field work conducted in April 2023
Geophiz.biz report number 115, Huttons Ambo, North Yorkshire
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Table of Contents
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Table of Contents .................................................................................................. 2
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Table of figures ..................................................................................................... 3
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Summary ............................................................................................................. 4
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Methodology ......................................................................................................... 5 4.1
Technique ......................................................................................................... 5
4.2
Software ........................................................................................................... 5
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Geology ............................................................................................................... 5
6
Location ............................................................................................................... 5
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Previous geophysical work ...................................................................................... 6
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Results and interpretation ...................................................................................... 8 8.1
Magnetic anomalies ............................................................................................ 8
8.2
Area 1 magnetic survey ...................................................................................... 8
8.3
Area 1 resistivity survey .................................................................................... 10
8.4
Area 1 LiDAR data ............................................................................................ 12
8.5
Area 1 cropmarks ............................................................................................. 13
8.6
Areas 2 and 5 magnetic survey .......................................................................... 13
8.7
Modern anomalies (17-19, 32-34 & 43) ............................................................... 15
8.8
Rig and Furrow (9-15 & 20-31) .......................................................................... 16
8.9
Possible archaeological features ......................................................................... 16
8.10
Areas 2 and 5 resistivity survey ....................................................................... 18
8.11
Areas 2 and 5 LiDAR data ............................................................................... 20
8.12
Areas 2 and 5 cropmarks ................................................................................ 21
8.13
Areas 3 and 4 magnetic survey ....................................................................... 22
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Area 3 resistivity survey....................................................................................... 24 9.2
Areas 3 and 4 LiDAR data .................................................................................. 26
9.3
Areas 3 and 4 cropmarks................................................................................... 28
9.4
Area 6 magnetic survey .................................................................................... 29
9.5
Rig and Furrow (71 -79) .................................................................................... 30
9.6
Upstanding earthworks (80-84).......................................................................... 30
9.7
Linear anomalies (85-89) .................................................................................. 30
9.8
Discrete anomalies (91-134) .............................................................................. 30
9.9
Area 6 resistivity survey .................................................................................... 32
9.10
Anomalies relating to upstanding earthworks (AI – AM) ...................................... 33
9.11
Anomalies relating to modern trees (AN – AQ) .................................................. 33
9.12
Linear anomalies (AV – AW)............................................................................ 33
9.13
Discrete anomalies (AR – AU & AX – AZ) .......................................................... 33
9.14
Area 6 LiDAR data ......................................................................................... 35
9.15
Area 6 cropmarks .......................................................................................... 37
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Conclusions ........................................................................................................ 37
10.2 11
Recommendations for further geophysical survey .............................................. 37
Bibliography ....................................................................................................... 39
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Appendix One - A3 geophysical survey plot ............................................................ 40
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Appendix two - A3 topographic survey plot ............................................................. 41
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Table of figures
Figure 1 Location of the surveyed areas in relation to the village of Low Hutton..................... 6 Figure 2 Plot of cropmarks derived from aerial photographs ................................................ 7 Figure 3 Dipolar anomalies in magnetic data ..................................................................... 8 Figure 4 Area 1 magnetic greyscale data plotted on the Ordnance Survey grid ...................... 8 Figure 5 Area 1 interpretation of magnetic data................................................................. 9 Figure 6 Area 1 resistivity greyscale data plotted on the Ordnance Survey grid ................... 10 Figure 7 Area 1 interpretation of resistivity data .............................................................. 11 Figure 8 Resistivity anomalies plotted on the LiDAR data .................................................. 11 Figure 9 Area 1 LiDAR data with hillshade from the north-west ......................................... 12 Figure 10 Pseudo-colour image of the LiDAR data for area 1 ............................................. 12 Figure 11 Cropmark plot (in red) derived from the National Mapping Program data .............. 13 Figure 12 Areas 2 and 5 magnetic greyscale data plotted on the Ordnance Survey grid ........ 14 Figure 13 Areas 2 and 5 interpretation of magnetic data................................................... 15 Figure 14 1st Edition Ordnance survey map with magnetic anomalies superimposed ............. 16 Figure 15 Detail view of potential archaeological anomalies .............................................. 17 Figure 16 Detail view of the interpretation of potential archaeological anomalies ................. 18 Figure 17 Greyscale plot of area 5 resistivity data ............................................................ 19 Figure 18 Interpretation of area 5 resistivity data (red areas not surveyed) ........................ 19 Figure 19 Areas 2 and 5 LiDAR data with hillshade from the north-west ............................. 20 Figure 20 Pseudo-colour image of the topographic data for areas 2 and 5 ........................... 21 Figure 21 Cropmark plot (in red) derived from the National Mapping Program data .............. 21 Figure 22 Areas 3 and 4 magnetic greyscale data plotted on the Ordnance Survey grid ........ 22 Figure 23 Areas 3 and 4 interpretation of magnetic data................................................... 23 Figure 24 Greyscale plot of area 3 resistivity data ............................................................ 24 Figure 25 Interpretation of area 5 resistivity data ............................................................ 24 Figure 26 1909 Ordnance Survey map ostensibly showing location the old church ............... 25 Figure 27 1st Edition Ordnance survey map, surveyed in 1851 ........................................... 25 Figure 28 Areas 3 and 4 LiDAR data with hillshade from the north-west ............................. 26 Figure 29 Pseudo-colour image of the topographic data for areas 3 and 4 ........................... 27 Figure 30 Cropmark plot (in red) derived from the National Mapping Program data .............. 28 Figure 31 Area 6 magnetic greyscale data plotted on the Ordnance Survey grid .................. 29 Figure 32 Area 6 interpretation of magnetic data ............................................................. 29 Figure 33 Detail view of possible pits in area 6 ................................................................ 30 Figure 34 Possible additional discrete anomalies (very faint) indicated by red lines .............. 31 Figure 35 Greyscale plot of area 6 resistivity data ............................................................ 32 Figure 36 Area 6 interpretation of resistivity data ............................................................ 32 Figure 37 Comparison of resistivity (red) with magnetometry (blue) results ........................ 33 Figure 38 Resistivity anomalies plotted on the LiDAR data ................................................ 34
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Figure 39 Area 6 LiDAR data with hillshade from the north-west ........................................ 35 Figure 40 Pseudo-colour image of the LiDAR data for area 6 ............................................. 36 Figure 41 25cm contour plot derived from the LiDAR data for area 6 .................................. 36 Figure 42 Cropmark plot (in red) derived from the National Mapping Program data .............. 37 Figure 43 Area 1, where potential further resistivity survey may be beneficial ..................... 38 Figure 44 Area 3, where surveying the remainder of the field would produce further evidence ................................................................................................................................. 38 Figure 45 Area 6, to elucidate an area containing a number of anomalies ........................... 39 Figure 46 All magnetic geophysical survey data on Ordnance survey grid ........................... 40 Figure 47 Topographic data displayed as a hillshade image on Ordnance survey grid ........... 41 Report information
Client
Huttons Ambo History Group
Report type
Fluxgate gradiometer and topographic survey
Location
Huttons Ambo (Low Hutton)
Unitary authority
North Yorkshire
Central grid reference
SE 76263 67803
Report number
GB 115
Site numbers
1876, 1877, 1878, 1879, 1880 & 1881
Dates of fieldwork
01-02/04/2023 & 15-16/04/2023
Date of report
18/11/2023 updated 18/12/2023
Fieldwork personnel
Philip Barraclough, William Blacker, Rona Charles, Richard Coates, Andy Dorman, Amanda Fordham, Emily Fordham, David Green, Alison Hewitt, Freddie Hewitt, Andrew Jackson, James Lyall, Graham Milner, Susan Milward, Richard Nesbitt, Emma Samuel, Michael Sessions, Tara Wallis and Diarmaid Walshe. Still need surnames for Matthew, Andrew, Alan and Ann
Report by 3
James Lyall MA (Hons), MSc
Summary
3.1.1 James Lyall (of Geophiz.biz) was commissioned by Emma Samuel (on behalf of the Huttons Ambo History Group) to undertake four geophysical training days over six pasture fields around Huttons Ambo, in North Yorkshire. Magnetometer surveys were carried out over all six of the areas, with five targeted resistivity surveys conducted in four of the fields. In addition, a drone survey of the northern part of the surveyed areas was carried out by Tony Hunt on 15/04/2023. 3.1.2 The magnetic survey detected a total of 134 magnetic anomalies, including ridge and furrow ploughing and some potential structural evidence. Recommendations for further survey areas in the village are given in the conclusions.
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Acknowledgements
The author would like to thank the Huttons Ambo History Group for inviting him to carry out the geophysical training days, and for the help given by Richard Coates, Emma Samuel and Diarmaid Walshe. Thanks also to all the volunteers who gave up two weekends for the training. Special thanks must go to the landowners who gave their permission for us to carry out the surveys (the names of the landowners need to go in here). The training days were made possible by a grant from CBA Yorkshire, and the writing of the report was funded by Ethos Heritage CIC.
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Methodology
5.1 Technique 5.1.1 The magnetic survey was conducted using a Sensys MXPDA 5 probe fluxgate gradiometer. The machine logs data at 10cm intervals along a 50cm traverse, so 20 readings per square metre are achieved. The machine uses a Trimble R8s GPS to locate each traverse, thus no grids are required. 5.1.2 Survey in the field, report production and archiving were conducted and prepared using the most up to date guidelines, as laid out in David et al (2008) and Schmidt (2013). 5.1.3 Although a full topographic survey was not carried out as part of the training, data derived from LiDAR (at nominal 50cm intervals) collected by the Department for the Environment, Food and Rural Affairs (DEFRA) has been downloaded and processed, and this is used to enhance the results of the geophysical survey report.
5.2 Software 5.2.1 The LiDAR data and the data from the magnetometer have been processed and presented using QGIS version 3.28. This report was produced using Microsoft Word 2010 and Adobe Photoshop 7 for further image manipulation. All maps (apart from the front cover) have north pointing to the top of the page, and Google Earth imagery was used as a background for the front cover and some of the location images. The remainder use an OpenStreetMap background.
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Geology
6.1.1 The underlying solid geology is part of the Lower Calcareous Grit Formation, comprising sedimentary bedrock (sandstone) formed between 163 and 157 million years ago in the Jurassic period. No drift geology is recorded for the survey areas (source BGS Geology Viewer - British Geological Survey).
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Location
7.1.1 The six survey areas are located around the village of Huttons Ambo, specifically Low Hutton (see Figure 1 for location). The areas requested for survey comprised a number of pasture fields. A total of 5.573 Ha of magnetometry (coloured in red on Figure 1) was surveyed, and 0.795 Ha of resistivity (coloured blue on Figure 1). In addition, a further 0.27 Ha of resistivity survey was carried out in area 5 (coloured yellow on Figure 1) by Richard Coates on 29/05/2023. Note the scheduled area to the south (outlined in green on Figure 1), which was not surveyed.
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Figure 1 Location of the surveyed areas in relation to the village of Low Hutton
7.1.2 Because the surveys were spread out around the village, in the interest of clarity each area (see Figure 1 for their location) will be discussed in turn. To avoid confusion, any anomalies detected by the magnetic surveys will use numbers to identify them, while for resistivity anomalies letters will be used.
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Previous geophysical work
8.1.1 It is not believed that any prior geophysical surveys have been conducted in the current area of interest (see Figure 1 for location). Two surveys were undertaken near High Hutton (one in 1987 by Geophysical Surveys Bradford, and another in 1992 by Geoquest Associates), but these have no bearing on the current survey areas.
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8.1.2 The region was covered as part of the National Mapping Program (Howardian Hill Mapping Project). This was one of the first areas to be completed, and as such is not available digitally. However, the data is free to view on the website Historic England Aerial Maps, where the cropmarks are indicated in red (see Figure 2 for an excerpt from this dataset, relating to the area where the geophysical surveys were carried out).
Figure 2 Plot of cropmarks derived from aerial photographs
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Results and interpretation Magnetic anomalies
9.1.1 Features discovered by magnetic survey techniques are referred to as “anomalies”, defined as such because they are different from the background magnetic norm. All magnetic survey plots relating to the current survey are plotted with a scale of +-7 nanoTesla (nT). 9.1.2 The large and small black and white areas in the greyscale images (see Figure 3) are dipoles (iron spikes), which indicate the presence of iron or steel objects. These are generally found in the topsoil, and although they could signify the presence of archaeological objects, it is much more likely that they relate to more modern detritus, such as broken ploughshares, iron horseshoes, shotgun cartridges etc. Figure 3 Dipolar anomalies in magnetic data
9.1.3 The data is displayed as an image (see Figure 4 for the greyscale plot, with a larger scale version on Figure 46), and as interpreted features on Figure 12. The magnetic variation across the surveyed area was generally medium, with 5 of the 13 anomalies detected relating to possible archaeological activity.
9.2 Area 1 magnetic survey
Figure 4 Area 1 magnetic greyscale data plotted on the Ordnance Survey grid
9.2.1 Area 1 is located to the north of Back Lane and south of Netherby Lane.
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Figure 5 Area 1 interpretation of magnetic data
9.2.2 Compared to the results of the resistivity and topographic surveys, the returns from the magnetic survey of area 1 can be classified as quite disappointing. However, a number of anomalies were detected (see Figure 5). 9.2.3 Anomalies 1 and 2 are both in the south-western part of the surveyed area, and are likely to have a modern origin. Anomaly 1 is rectangular, and may indicate the base of a former structure. Anomaly 2 is curvilinear, possible a services trench of some kind. Note also that there are a large number of dipolar anomalies in this vicinity, indicating relatively recent disturbance. 9.2.4 Anomalies 10 and 11 are amorphous, and show indications of areas of disturbance. 9.2.5 While anomalies 5 (curvilinear) and 6 (linear), could be archaeological, it seems more likely that they have a geological origin, as they are the point where the ground begins to fall off to the north. 9.2.6 The remaining anomalies (4, 7, 8 and 9) are all potentially archaeological in origin. They are all represented by low earthworks on the ground, apart from number 7. It is likely that they relate to Medieval or later settlement in this field. Anomaly 8 is slightly different in magnetic character, being very weak.
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Area 1 resistivity survey
9.3.1 The resistivity survey (a single 30m square grid) was informative, though difficult to interpret, as the high resistance anomalies (lighter colours on Figure 12) were almost filling the square.
Figure 6 Area 1 resistivity greyscale data plotted on the Ordnance Survey grid
9.3.2 An interpretation of the resistivity anomalies has been attempted (see Figure 7), where six distinct areas of higher resistance have been identified. It is likely that all of these are related to Medieval or later settlement. Given the good response of the resistivity meter here, it is recommended that further resistivity survey be conducted in this field. 9.3.3 The correlation between the high resistance anomalies and the earthworks was good, almost all of them being represented in the topographic data (see Figure 8, where they are plotted with the LiDAR data as a background image).
Geophiz.biz report number 115, Huttons Ambo, North Yorkshire
Figure 7 Area 1 interpretation of resistivity data
Figure 8 Resistivity anomalies plotted on the LiDAR data
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9.4 Area 1 LiDAR data
Figure 9 Area 1 LiDAR data with hillshade from the north-west
9.4.1 The hillshade plot of the LiDAR data (see Figure 9) is very informative, and a plethora of low earthworks features are present (note that the z-exaggeration of the features is five times greater than the actual values).
Figure 10 Pseudo-colour image of the LiDAR data for area 1
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9.4.2 The pseudo-colour image of the data shows that the ground is highest in the west, dropping off to the east and particularly to the north (blue colours show the lowest values on Figure 10).
9.5 Area 1 cropmarks
Figure 11 Cropmark plot (in red) derived from the National Mapping Program data
9.5.1 There are only three cropmarks within area 1, and one of these coincides with anomaly 4, although the angle is slightly different. The other two linear cropmarks are not associated with anomalies.
9.6 Areas 2 and 5 magnetic survey 9.6.1 The magnetic anomalies for these two areas were have been divided into four categories, those that relate to probable modern or recent activity (coloured magenta on Figure 13, those which relate to rig and furrow (coloured light green) and those that are potentially of archaeological significance (coloured dark blue, light blue and red on Figure 13). Note also that no cropmarks were present in the data for these two areas.
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Figure 12 Areas 2 and 5 magnetic greyscale data plotted on the Ordnance Survey grid
9.6.2 Unlike the returns from area 1 to the south-west, here the magnetic anomalies are showing clearly in both areas. The two areas show a marked difference in their response, with area 2 having very strong anomalies, while they are more muted in area 5. It is likely that area 2 has seen very little ploughing in recent times.
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Figure 13 Areas 2 and 5 interpretation of magnetic data
9.7 Modern anomalies (17-19, 32-34 & 43) 9.7.1 Anomalies 17 and 18 (coloured magenta on Figure 13) are areas of disturbance, with a higher concentration of dipolar anomalies than is seen in other parts of the surveyed areas. There is a faint hint of a line in area 17, which could indicate a possible services trench at this location. Area 18 may have something to do with the house to the west (possible gardens, see Figure 14). 9.7.2 Anomaly 19, though linear, is clearly made up of a number of discrete strong dipolar anomalies. This would normally indicate a fence of some description, potentially with iron spikes on the base, which would then remain in the ground, causing the anomalies. 9.7.3 Anomalies 28 and 32 may be related, as they are both on a similar alignment, which is different to the rig and furrow, although it is possible that 28 could still be a furrow. Linear anomaly 33 extends westwards from 32, but not for very far. Linear anomaly 34 is on a similar alignment to the furrows, but is clearly later. Both 32 and 34 are visible on the ground and in the LiDAR data, and are almost certainly some form of later field division. This is verified by the 1st Edition Ordnance Survey map (published in 1854, see Figure 14) where anomaly 32 is indicated by a line of trees, and anomaly 34 is shown as a field boundary (now removed).
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Figure 14 1st Edition Ordnance survey map with magnetic anomalies superimposed
9.8 Rig and Furrow (9-15 & 20-31) 9.8.1 Both areas have magnetic evidence for rig and furrow, indeed it is still extant in area 2, and to a lesser extent in area 5. The rig and furrow in these fields have the furrows in the same direction, indicating this might have been a single field in the Medieval period. Note that anomalies 9 and 13 are both bigger than the other anomalies, which might indicate boundaries, although they cannot be classified as headlands, as these occur at the ends of the furrows.
9.9 Possible archaeological features 9.9.1 The remaining interpreted anomalies are grouped into different types of potential archaeological anomaly. The anomalies coloured dark blue are linear, but do not appear to belong to the rig and furrow fields. The anomaly in area 2 (number 16) seems to form a right angle, possibly the north-eastern corner of a feature. It is not possible to say whether this is structural, but it is more likely to be a boundary of some sort. 9.9.2 Linear anomaly 35 is also visible on the ground, and is the western extent of a bank which heads east, before turning north, and extending for a considerable distance (almost 600m, not surveyed, but seen on the LiDAR data). 9.9.3 Possibly the most interesting of the potential archaeological anomalies is the group coloured light blue. They are located on a slightly raised platform, where resistivity survey was also carried out.
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Figure 15 Detail view of potential archaeological anomalies
9.9.4 Although there are no obvious structural elements within this area, there is what appears to be a square (arrowed on Figure 15). It is possible that a second square (number 42 on Figure 16) is immediately to the south (connected?), but this is not as clear. A third square can be made out to the south of the black arrow (numbered 39 on Figure 16). 9.9.5 There is an area of disturbance (numbered 43 on Figure 16), which is difficult to interpret. 9.9.6 Anomaly 38 is located immediately to the north of anomaly 40, and extends to the west, although taking an odd turn to the south as it does so. It appears to continue to the west, albeit after a gap of just over 10m.
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Figure 16 Detail view of the interpretation of potential archaeological anomalies
9.9.7 The remainder of potential archaeological anomalies (coloured red and numbered 44 to 49 on Figure 13), are all discrete, and may indicate the presence of pits at these locations, though it is always possible that they might represent natural features.
9.10 Areas 2 and 5 resistivity survey 9.10.1 As indicated above, three 30m grids were carried out as part of the training exercise. Three further grids were added to this on the 29 th May, and these will also be dealt with here. Having said that, this did cause some problems, as the soil was much dryer at the time of the second survey, and so the resistivity responses were different to those from the original dataset (see Figure 17).
Geophiz.biz report number 115, Huttons Ambo, North Yorkshire
Figure 17 Greyscale plot of area 5 resistivity data
Figure 18 Interpretation of area 5 resistivity data (red areas not surveyed)
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9.10.2 The areas in red on Figure 18 were not surveyed due to trees. The linear anomalies marked in green are probably caused by Medieval furrows, with the lower resistance (darker) areas present because the furrows retain more moisture. 9.10.3 Linear anomalies G and H are caused by the low linear earthwork which is present here, and are part of the old field boundary noted on the 1 st Edition Ordnance Survey map (see Figure 14). 9.10.4 The remainder of the anomalies are of an uncertain origin, and are possibly geological. There appear to be no obvious anomalies associated with structures in the resistivity data for this area.
9.11 Areas 2 and 5 LiDAR data
Figure 19 Areas 2 and 5 LiDAR data with hillshade from the north-west
9.11.1 For the hillshade plot Figure 19, rather than limit the topographic plot to the extent of the survey areas, the entire area has been included. This is because it gives a much better picture of the extent of the rig and furrow present in the two fields. Note that there is a change in the way the furrows look, almost exactly where the old field boundary noted above is present. This could indicate either that there was a boundary here from the Medieval period onwards, or that the fields on either side of a more recent boundary were treated differently.
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Figure 20 Pseudo-colour image of the topographic data for areas 2 and 5
9.11.2 The pseudo-colour plot on Figure 20 clearly shows the slope from north-west to the south and east. As before, the redder tones are higher elevation values, moving down through orange and yellow to green and then the lowest values are indicated in blue.
9.12 Areas 2 and 5 cropmarks
Figure 21 Cropmark plot (in red) derived from the National Mapping Program data
9.12.1 Only two cropmarks were present, both in area 2. They are clearly part of the rig and furrow system.
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9.13 Areas 3 and 4 magnetic survey
Figure 22 Areas 3 and 4 magnetic greyscale data plotted on the Ordnance Survey grid
9.13.1 The most obvious difference in the magnetic data for these areas (particularly area 3, but also the western part of area 4, these are not numbered, apart from anomaly 54, as they are related to the infilling of the small quarry pits in this location) is the number of dipolar anomalies present here. This indicates quite a high level of probably relatively recent disturbance in these locations. There is also a higher density of small dipoles in the north-eastern part of area 4. 9.13.2 There are a number of lines of very strong dipolar signals in area 3 (numbered 50-52 and coloured magenta on Figure 23). These are likely to indicate where posts have been in place at some point in the past. Anomaly 53 is also a very strong linear dipolar, possibly indicating the presence of some form of service pipe here. 9.13.3 Anomaly 54 is another linear dipolar, and may also indicate the presence of a pipe at this location, although this is not certain, due to the masking effect of the other dipolar anomalies in the immediate vicinity. 9.13.4 Linear anomaly 56 is unusual in that it is a negative (darker) anomaly. It is likely this is caused by a wheel rut, as this is the route into the field.
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Figure 23 Areas 3 and 4 interpretation of magnetic data
9.13.5 Like anomaly 56, linear anomalies 67 and 68 in area 4 are also negative, and anomaly 67 is also present in the LiDAR data. They are shallow ditches, both of which happen to be within the bounds of the remains of the rig and furrow present in this field, so the likely explanation for these is for drainage. 9.13.6 The remainder of the anomalies are more likely to be of archaeological interest. Linear anomalies 61 to 66 are all very wide, and may indicate the remains of ploughed out ridge and furrow. There are hints of this in the LiDAR data, but it is not as clear as the furrows in the fields to the north-west (areas 2 and 5). There is also a slight difference in the orientation of the two anomalies in the south, which could indicate a different phase or function. 9.13.7 The other two anomalies in area 4 are potentially intriguing, as anomaly 70 (coloured green on Figure 23) is on a different alignment to all of the others in the area. It may have been a narrow trackway, though this is not clear from the magnetic data alone. Anomaly 69 (coloured light blue on Figure 23) is discrete, and is located just to the north of the field wall. It may be a small quarry pit. 9.13.8 There are a number of linears in area 3 which may be of archaeological significance. Linear anomaly 58 is on the same alignment as the western part of the current field wall, and may indicate that the wall used to be straighter than it is today, although by 1851 (the 1st edition Ordnance survey), the wall was already in its current position. 9.13.9 Linear anomaly 59 is part of an upstanding earthwork which extends into the scheduled area to the south. It appears to be some form of entrance in the scheduled site. Anomaly 60 is right-angled, and may attach to anomaly 59. There are two further angled anomalies in area 3 (numbered 55 and 57), both located to the north-west of the scheduled area. Anomaly 55 in particular appears to form a right angle, thus could be structural.
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10 Area 3 resistivity survey
Figure 24 Greyscale plot of area 3 resistivity data
Figure 25 Interpretation of area 5 resistivity data
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10.1.1 This part of area 3 was targeted for resistivity survey as there was some indication that the site of a previous church had been located here. This information was mainly from the 1909 Ordnance survey map, which marked the site with a small cross (see Figure 26).
Figure 26 1909 Ordnance Survey map ostensibly showing location the old church
10.1.2 However, it is likely that this information was derived from the original Ordnance Survey map from 1851, published in 1855, some 58 years previously (see Figure 27).
Figure 27 1st Edition Ordnance survey map, surveyed in 1851
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10.1.3 Figure 27 (derived from the 1st Edition Ordnance Survey map, surveyed in 1851) indicates “Site of Church”, but it is not clear from this map whether this is located where the text is placed (unlikely), or to the west or east of this annotation. The surveyors of the 1909 Ordnance Survey map chose to place it on the small grassy area to the east (our survey target), but it may have been in another location. Note also that a “Sandstone Quarry” is also indicated just to the south-west, but there is no evidence for a quarry at this location, either in the 1st or later editions of the Ordnance Survey. 10.1.4 There are 17 resistivity anomalies which have been interpreted, mostly higher resistance anomalies (the lighter coloured areas on Figure 24), although there are also five lower resistivity anomalies (the darker areas). 10.1.5 It is difficult to provide a function for these, as there is relatively little coherence between the anomalies, and also, the area is quite small. However, there are some patterns which can be identified. Eight anomalies lettered R to Y are discrete higher resistance signals, with S, T and U possibly linked by a higher resistance linear anomaly (AA). These could be some form of drainage. 10.1.6 There is a linear anomaly (AC) near the eastern edge of the survey, although this is difficult to interpret. A linear anomaly (AB)is also present along the western edge, here partly equivalent to magnetic anomaly 53, indicating a possible service trench. 10.1.7 The most coherent of the resistance anomalies is lettered Z, and runs east-west across the surveyed area. While it is possible that it could indicate the presence of a small wall, it is equally likely to be some form of service trench. 10.1.8 The remaining five anomalies are all discrete negatives, again forming no obvious pattern, though it could be argued that AE, AF and AG are in a line. Note that anomaly AD is larger than the other negative features.
10.2 Areas 3 and 4 LiDAR data
Figure 28 Areas 3 and 4 LiDAR data with hillshade from the north-west
10.2.1 The hillshade image of the topographic data for areas 3 and 4 has been extended to take in the scheduled monument to the south-east. There are a number of points of note here.
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10.2.2 The first is that the linear feature detected by the magnetic survey (numbered 59 on Figure 23) is clearly visible as an earthwork (letter A on Figure 28), and is associated with the scheduled monument, although it may be part of a later phase of activity. 10.2.3 Secondly, the area lettered B on Figure 28 is clearly associated with quarrying (not marked on the 1st Edition Ordnance Survey map, Figure 27, but partly indicated on the 1909 Ordnance Survey, Figure 26). The quarrying clearly continued to the east after 1909. 10.2.4 The earthwork numbered C on Figure 28 runs east-west across the entire area, and is correlated with magnetic anomaly 67 (also present as a cropmark, see Figure 30). This still appears likely to be more recent in origin, possibly a field division or drainage of some sort. Having said that, it is not present on any of the Ordnance Survey maps of the area. 10.2.5 There is a sinuous feature (lettered D on Figure 28) which was not covered by the magnetic survey. The function of this feature is unclear.
Figure 29 Pseudo-colour image of the topographic data for areas 3 and 4
10.2.6 It is worth pointing out that the area where the church is supposed to be located has quite a slope (dropping around 4m over 55m from south to north). Churches were normally built on higher ground, and also on a level area, and usually if the church was to be constructed on a slope, the ground would first be made up to level, so as noted above when discussing the Ordnance Survey map data, it appears unlikely (but not impossible), that this was the location of the previous church.
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10.3 Areas 3 and 4 cropmarks
Figure 30 Cropmark plot (in red) derived from the National Mapping Program data
10.3.1 The scheduled monument is present, as well as two cropmarks correlated with magnetic anomalies 58 and 59 (see Figure 23). As mentioned above, the cropmark in area 4 correlates with magnetic anomaly 67.
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10.4 Area 6 magnetic survey
Figure 31 Area 6 magnetic greyscale data plotted on the Ordnance Survey grid
Figure 32 Area 6 interpretation of magnetic data
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10.4.1 Area 6 contained more magnetic anomalies (60) than any of the other areas. There were also a number of different types of anomaly detected. These were ridge and furrow (coloured green on Figure 32), standing earthworks (coloured cyan), a possible quarried area (coloured red and numbered 90 Figure 32), linear anomalies (coloured purple) and a number of discrete anomalies (coloured blue on Figure 32).
10.5 Rig and Furrow (71 -79) 10.5.1 Nine anomalies (coloured green on Figure 32) have been interpreted as being part of the Medieval field system, although here they are separated, with 71-75 in the west, and 76-79 in the east. The furrows in the east are fragmentary, and do not show as clearly as those in the west.
10.6 Upstanding earthworks (80-84) 10.6.1 In the southern part of the surveyed area there were a number of upstanding earthworks (the magnetic anomalies associated with these earthworks are coloured blue and numbered 80-84 on Figure 32). They appeared to form the northern part of some form of enclosure system. Although not clear from the magnetic evidence alone, it seems likely that they overlie the ridge and furrow.
10.7 Linear anomalies (85-89) 10.7.1 There are five linear anomalies (numbered 85-89 and coloured purple on Figure 32). It is possible that 86 and 87 form part of the same curvilinear feature, but unfortunately this part of the area could not be surveyed due to the presence of trees. These and anomaly 88 may have a relationship with a group of discrete anomalies in this location (see below for further discussion).
10.8 Discrete anomalies (91-134)
Figure 33 Detail view of possible pits in area 6
10.8.1 There were a total of 43 of this type of anomaly (coloured blue on Figure 32). Discrete anomalies are difficult to interpret, as they can often be caused by geological factors. These have been identified as of potential significance because this type of anomaly was not present in any of the other survey areas, and here they
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seem to be confined to particular parts of the area. There are two groups of this type of anomaly. 10.8.2 The eastern (smaller, 12 anomalies) group was numbered 91 to 102 (see Figure 32), and was quite scattered. Also there were different strengths of anomaly, and different sizes. In particular, anomaly 97 was the largest, and almost rectangular in shape. It together with anomalies 94 and 100, were strong magnetic signals. This tends to indicate that the anomalies may be from different phases, or have different functions. 10.8.3 The western cluster of discrete anomalies (31, numbered 103-134) is much more coherent. The detail view of the anomalies makes it clearer that there are potentially a number of linear alignments of these features (see Figure 33, where the possible alignments have been connected by red lines). While there are no obvious total structures present in the data, this does not mean that these anomalies (or at least some of them) may not have a structural function. Whether the linear anomalies in this area are associated with them is not clear.
Figure 34 Possible additional discrete anomalies (very faint) indicated by red lines
10.8.4 There are also a number of much fainter anomalies, which might also be in an alignment. They were not interpreted in the main drawing, as the confidence level regarding the veracity of them as anomalies is low, but because they are in this vicinity, they have been noted here, and are indicated inside the red lines on Figure 34).
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10.9 Area 6 resistivity survey
Figure 35 Greyscale plot of area 6 resistivity data
Figure 36 Area 6 interpretation of resistivity data
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10.9.1 A total of 18 anomalies (lettered AI to AZ on Figure 36) were detected by the two resistivity surveys carried out in area 6. Again they can be divided into a number of subcategories.
10.10 Anomalies relating to upstanding earthworks (AI – AM) 10.10.1 Five anomalies (coloured lighter green on Figure 36) could be identified as relating to the upstanding earthworks in this part of the surveyed area. Here they give slightly greater detail than that achieved by the magnetic survey, and indeed it seems as though the two types of survey are finding different parts of the construction of the earthworks, as they do not exactly match (see Figure 37, where the resistivity interpretation is presented in red, and the magnetometry in blue). Also, the comparison with the LiDAR data is pertinent (see Figure 38), as there is a good correlation between the resistivity anomalies and the upstanding earthworks.
Figure 37 Comparison of resistivity (red) with magnetometry (blue) results
10.11 Anomalies relating to modern trees (AN – AQ) 10.11.1 There are at least four areas of higher resistance (lettered AN-AQ and coloured darker green on Figure 36), which may well relate to the presence of trees in the immediate vicinity. This is because the tree roots are efficient at removing the moisture, and therefore the soil is dryer under the trees than in other places in the survey area.
10.12 Linear anomalies (AV – AW) 10.12.1 Two linear anomalies were detected, both of them in the northern surveyed area. Anomaly AV can be correlated to magnetic anomaly 89, and also with part of the Historic England cropmark plot (see Figure 42). Anomaly AW can be correlated with magnetic anomaly 85.
10.13 Discrete anomalies (AR – AU & AX – AZ) 10.13.1 There were seven discrete anomalies detected by the resistivity survey. Four of these were low resistance (darker on Figure 35, and coloured purple and lettered AR-AU on Figure 36). It is difficult to provide an interpretation for these anomalies, it
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may be that they were just slightly wetter areas. The three higher resistance anomalies (coloured light red and lettered AX-AZ on Figure 36) all have a correlation to magnetic anomalies, with AX correlating with magnetic anomaly 100, AZ with the large rectangular magnetic anomaly 97, and AY with a large dipolar anomaly (not shown on the magnetic interpretation drawings).
Figure 38 Resistivity anomalies plotted on the LiDAR data
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10.14 Area 6 LiDAR data
Figure 39 Area 6 LiDAR data with hillshade from the north-west
10.14.1 For area 6, it is once again the hillshade plot which provides the greater detail regarding the topography in this area. The earthworks in the south can be clearly seen, as can the ridge and furrow ploughing in the south-west. Indeed in the east, even where both types of geophysical survey either failed to detect (resistivity) or only partially detected (magnetometry) the ridges in the eastern part of the site, the LiDAR demonstrates beyond doubt that the ridge and furrow is present across the whole western part of the area. 10.14.2 It is also clear that there appears to have been some major reworking of the landscape along the northern edge of the area, where possibly a trackway has been present, heading down towards the river. The possible quarried area identified in the magnetometer data (numbered 90 on Figure 32), is plainly visible in the LiDAR data as an area of disturbance, and is located immediately to the south of the possible trackway. 10.14.3 The pseudo-colour version of the topographic data is not quite as informative, although the disturbed area associated with the supposed quarry is visible, as is the possible trackway in the northern part of the plot. It does show that the area slopes down from the south-west to the north-east, although it is quite flat in the southeast.
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Figure 40 Pseudo-colour image of the LiDAR data for area 6
Figure 41 25cm contour plot derived from the LiDAR data for area 6
10.14.4 However, it is the 25cm contour plot (see Figure 41), which shows the potential trackway in the north to the best effect. Note also the disturbed area just to the south of this. It is worth pointing out here that the zone which contained the
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majority of the discrete anomalies, including the possible lines, is relatively flat, although there is a gentle slope down to the east at this point. At this stage, looking at the wider picture provided by the full hillshade plot of the LiDAR data for the whole area (see Figure 47) would be beneficial. This shows the extent of the ridge and furrow which still remains in and around the village.
10.15 Area 6 cropmarks
Figure 42 Cropmark plot (in red) derived from the National Mapping Program data
10.15.1 As is clear from Figure 42, the cropmark plot for this area has only two features. The easternmost is almost certainly related to the earthwork here, as indeed is the southern part of the eastern cropmark, although this one extends to the north (here joining up with one of the linear anomalies (numbered 89 on Figure 32).
11 Conclusions 11.1.1 In conclusion, it can be stated that the magnetic surveys of the six areas were successful in detecting a total of 134 anomalies. The four areas where resistivity surveys were conducted found a total of 47 anomalies. The surveys were complementary, although both survey types also produced anomalies which were not detected by the other. They demonstrated that Medieval ridge and furrow was to be found throughout the survey areas, but also that parts of some of the areas (1, 3 and 6) might benefit from further geophysical research.
11.2 Recommendations for further geophysical survey 11.2.1 In terms of further geophysical survey, there are at least three places where additional survey could add further detail and clarity to the results documented in this report. These are to be found in areas 1, 3 and 6. 11.2.2 In area 1, no further magnetometry is proposed, here it is the resistivity which would provide further benefits. The area to be surveyed would be to the north of the single 30m square grid carried out here originally (see Figure 43, area shaded in red). The
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magnetometry hints at something of potential interest here, even if the topographic data is not convincing.
Figure 43 Area 1, where potential further resistivity survey may be beneficial
Figure 44 Area 3, where surveying the remainder of the field would produce further evidence
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11.2.3 In area 3, it is the southern part of the field which will give further knowledge (shaded red on Figure 44. Here, a section 42 license will have to be applied for, as it contains part of scheduled monument list number 1014384. This will produce a fuller picture, allowing us to see the relationship between what we discovered and the scheduled area. Should any potential structures be encountered, targeted resistivity survey could be carried out over these.
Figure 45 Area 6, to elucidate an area containing a number of anomalies
11.2.4 In area 6, it would be useful to resurvey the area shaded in red on Figure 45 at a higher resolution with the magnetometer (25cm rather than 50cm), as this would help to identify smaller features, and to elucidate those already discovered. It would also be useful to survey all of this area with the resistivity meter, to check whether any potential wall lines could be detected.
12 Bibliography David, A. et al, (2008) Geophysical Survey in Archaeological Field Evaluation (2nd edition). English Heritage Publishing. Schmidt, A. (2013) Geophysical Data in Archaeology: A Guide to Good Practice (2 nd edition).
13 AppendixOne - A3geophysical surveyplot
Figure46Allmagneticgeophysical surveydataonOrdnancesurveygrid
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14 Appendix two - A3 topographic surveyplot
Figure47Topographicdatadisplayed asa hillshade imageonOrdnancesurveygrid
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