Survey Summary

GEOPHYSICAL SURVEY AT CLOVERHAYES, SMALLRIDGE EAST DEVON

Dr Chris Smart, Department of Archaeology, University of Exeter, Laver Building, North Park Road, Exeter EX4 4QE

October 2017

Contents

Summary 3

1. Introduction 5 1.1 Site description 5 1.2 Land use 6 1.3 Geology and soils 6 1.4 Prevailing weather 6 1.4 Known limiting factors 6 1.5 Site history and archaeological potential 6

2. Aims 7

3. Method 7 3.1 Survey design 7 3.2 Data processing 7

4. Results and discussion 8 4.1 Results 8 4.2 Discussion 9

5. Significance 9

Acknowledgements 10

References 10

Appendix 1. Survey grid reference co-ordinates Appendix 2. Field boundary and gate post co-ordinates

Figure 1. Site location Figure 2a. The site as depicted on the 1838 Axminster tithe map Figure 2b. The site as depicted on the 1890 Ordnance Survey 1st edition 25” to 1 mile Figure 2c. The site as depicted on the 1905 Ordnance Survey 1st edition 25” to 1 mile first revision Figure 2d. The site as depicted on the 1963 Ordnance Survey National Grid 1:10560 Figure 3. Greyscale shade plot of raw data Figure 4. Trace plot of raw data Figure 5. Greyscale shade plot of processed data Figure 6. Trace plot of processed data Figure 7. Interpretation of data

Summary

Name of site: Land at Cloverhayes, Smallridge, East Devon Parish: Axminster Grid reference (centre): NGR 329927 101191 Devon HER number: MDV 115825 (possible Roman camp) Date(s) of survey: 27th February to 1st March 2017 Author and lead surveyor: Dr Chris Smart (Department of Archaeology, University of Exeter) Assistant surveyor(s): Dr João Fonte, Dr Lukáš Holata, Jake Godfrey (Department of Archaeology, University of Exeter)

Site: The site consists of a single field immediately south of Cloverhayes, an early/mid twentieth-century residence situated 400m northwest of the hamlet of Smallridge, in East Devon. The site occupies an elevated position, between 98m and 87m AOD, with extensive outward views particularly south towards Axminster. The Blackdown Hills AONB and East Devon River Catchments National Mapping Programme (NMP) Project identified cropmarks that potentially reveal the position of a Roman camp or similar enclosure of archaeological interest. The field is laid to pasture but has evidently been cut for hay. It is used by the owners to graze horses. There is no indication that the site has been ploughed in recent years.

Geology and soils: The site is located upon Cretaceous sandstone of the Upper Greensand Formation overlain by clay (British Geological Survey 2010)

Survey type: Magnetometer (gradiometer) survey Equipment: Bartington Instruments Ltd. Grad601-2 Configuration: Dual sensor Area surveyed: 2ha Grid size: 30m by 30m Traverse method: Zig-Zag and Parallel Traverse interval: 1m Sample interval: 0.25m

The survey and reporting was done in accordance with English Heritage guidelines Geophysical Survey in Archaeological Field Evaluation (2008).

Results: Geophysical survey (magnetometer) of land to the south of Cloverhayes has revealed evidence for a hitherto unknown area of possible settlement and enclosure, although the date of this cannot be deduced on morphological grounds alone. There are also traces of land division or drainage on a different orientation, but not conforming to the axis of the present-day historic landscape. Whilst no firm conclusions can be drawn about the age and character of the buried remains but it is evident that there is no support in the results of the magnetic survey for the anomalies transcribed from aerial photographs. Specifically, there is no evidence for a rectilinear enclosure or Roman camp.

1. INTRODUCTION This report presents the results of geophysical survey (magnetometer) of land at Cloverhayes, Smallridge, East Devon (Figure 1; ST 29927 01191). The site comprises a long triangular-shaped field immediately south of Cloverhayes, on the northwest edge of Smallridge hamlet. The survey was undertaken by Dr C. Smart and Dr J. Fonte, with assistance from Dr L. Holata and J. Godfrey, (Department of Archaeology, University of Exeter) between the 27th February and 1st March 2017. The survey was commissioned and funded by Devon County Council and the Blackdown Hills Area of Outstanding Natural Beauty as follow-up reconnaissance to the Historic England-funded Blackdown Hills AONB and East Devon River Catchments National Mapping Programme (NMP) Project. The purpose of the survey was to define the extent, nature and significance of any sub-surface archaeological remains whether corresponding to the recognised vegetation marks or not. The possibility of the site being once occupied by a Roman camp would have provided significant new evidence for the character of military movement through the south west of Britain in the middle decades of the first century AD.

1.1 Site description The surveyed area consists of a single field south of Cloverhayes, an early/mid twentieth-century residence situated 400m northwest of the hamlet of Smallridge, in East Devon. Smallridge lay on the northern edge of Axminster parish, in close proximity to the County border between Devon and Dorset. The site is 2.5km north of the Roman, and later, medieval small town of Axminster and only 1km west of the Fosse Way. First-century Roman military activity is already known in this region, with a fort recorded at Woodbury Farm, Axminster (Silvester and Bidwell 1984; Weddell et al. 1993), and a substantial Roman road recorded crossing the river Axe heading west towards Exeter (ibid.). The historic settlement pattern of this region is characterised by a multitude of small farms dispersed between a number of hamlets and small villages such as Smallridge, Membury and Churchill. It is a rich agricultural landscape dominated by dairying and beef-production with some sheep rearing and arable cultivation. The site is situated on a promontory above a tributary of the River Axe, at an elevation of between 98m and 87m AOD. Not only is the site topographically advantageous for defence but there are also good outward views to Axminster and a direct line of site to the known Roman fort at Woodbury Farm. The fields in this area are enclosed by earthen banks with a rubble core, upon which grows scrubby hedges with some larger trees. These fields often have straight boundaries but also have more irregular components too, and have been classified in the Devon County Council Historic Landscape Characterisation as ‘post-medieval enclosures with medieval elements’. In terms of chronology it is suggested that there fields might originate in the medieval period but have undergone substantial reorganisation in the post-medieval period (http://map.devon.gov.uk/dccviewer/?bm=OSGreyscale&layers=Historic%20Environ ment;14&activeTab=Historic Environment&extent=210063;25600;338387;151675). The changes in boundary configuration seen on historic maps, and the lost boundary recorded in the geophysical survey (outlined below) attest the reorganisation of enclosures here.

1.2 Land use When surveyed the field was under permanent grass and had been used for grazing horses.

1.3 Geology and soils The site is positioned on Cretaceous sandstone of the Upper Greensand Formation overlain by clay (British Geological Survey 2010)

1.4 Prevailing weather Weather conditions were cool with a moderate westerly wind and frequent heavy rain showers throughout the period of survey.

1.5 Known limiting factors and potential causes of interference A number of factors may have influenced the clarity of magnetic survey results. A post and electric-wire fence had been installed along the southern and eastern boundaries and, whilst not live, may cause metallic interference. A five-bar metal gate marked the entrance to the field from the lane to the south. It was noted that whilst the field was under pasture that there was a spread of fine mixed mulch spread all across it. This included burnt wood, fragments of chipboard, some shredded plastic – all generally indicative of building waste. If this included ferrous debris, brick or tile (thermoremnant material) this might cause irregularities within the data.

1.6 Site history and archaeological potential

1.6.1 Archaeological background The historic landscape south of Cloverhayes comprises fields with a mix of straight and less regular boundaries, which might indicate that it is essentially medieval in origin but has been re-organised in the post-medieval period. Consultation of historic mapping shows two significant boundary changes within the site (Figure 2a-2d). The tithe map of 1838 shows the present day field as three separate enclosures – 434, 435 and 439 – and Cloverhayes has not yet been built. By 1890, when the Ordnance Survey 1st edition 25 inches to the mile map was drafted, the boundary between tithe field 435 and 439 had been removed. Neither this map series, nor the 1905 first revision, shows Cloverhayes but the two-field configuration of the site persists. Between 1905 and 1963, the latter being the date of the Ordnance Survey National Grid 1:10560 map, Cloverhayes was built. During this time there was also a reconfiguration of the two fields as the dividing boundary was shifted south to create two broadly equally sized fields. This new boundary was, based on its appearance on 2002 Google Earth imagery, formed by a wooden post and rail fence. The same overall configuration is still seen on modern OS digital Vectormap mapping, although the reality is that the dividing boundary has now been removed and what were once three fields, then two fields, is now one large field. Google Earth imagery shows that the post and rail fence was removed between 2010 and 2013. No previous archaeological investigations have taken place on the site and, other than the potential rectilinear enclosure identified by the Historic England-funded Blackdown Hills AONB and East Devon River Catchments NMP Project being undertaken by Cain Hegarty, Stephanie Knight and Richard Sims for Devon County Council (MDV 115825), there is no evidence to indicate the archaeological potential

of the site. The tithe field-names are Nap Ground (enclosure numbers 434 and 435) and Hither Nap Ground (enclosure number 439), which offer little information.

1.6.2 Archaeological potential The site has some archaeological potential as the Blackdown Hills AONB and East Devon River Catchments NMP Project has identified vegetation marks that may depict a rectangular enclosure. The dimensions and morphology of the potential enclosure are reminiscent of a Roman camp, previously unknown, which would add to the broader understanding of military movement across the southwest. The situation and aspect of the site supports this possibility.

2. AIMS The principal aim of the geophysical survey is to define the likely extent and character of the potential archaeological resource within part of a single field at Cloverhayes, where vegetation marks seen on aerial photographs might suggest the presence of a previously unrecorded Roman camp.

3. METHOD An area of approximately 2ha was subject to magnetometer (gradiometer) survey. Magnetometer survey was selected as a proven method of accurately and rapidly detecting archaeological features. The survey was undertaken in accordance with English Heritage guidelines presented in Geophysical Survey in Archaeological Field Evaluation (2008).

3.1 Survey Design Twenty-five complete and partial 30m by 30m survey grids were set-out in relation to the boundaries of the site using a Leica TCR 1200 EDM total station. They were positioned to maximise coverage in the available time. They were set-out on a best-fit basis, maximising coverage of whole grids. The grid corner points were laid with an internal accuracy of +/- 0.05m. The grids were located according to the Ordnance Survey National Grid using a Leica System 1200 differential Global Positioning System that has a typical three-dimensional global position accuracy of 10-15mm. National Grid Reference co-ordinates for each of the grid points is given in Appendix 1. The position of fence-posts along the site boundary was recorded in order to provide a reference from which the position of any archaeological features can be measured in the future. The position of these in relation to the Ordnance Survey National Grid was determined using the same Leica differential GPS. The NGR co- ordinates for these points are given in Appendix 2. The magnetic survey was undertaken using a Bartington Instruments Ltd. Grad601-2 dual sensor gradiometer sampling four readings per metre at 1m traverse intervals in the 1nT range. The traverses were variously sampled in a zig-zag (whole grids) or parallel pattern (grids abutting the western boundary). The direction of the first traverse was northwest.

3.2 Data Processing The magnetic survey data was downloaded to an IBM-compatible laptop computer using the Bartington Instruments Ltd proprietary software Grad-601. The data was processed using GeoPlot 3.0, written by Geoscan Research. Processed data, which

had a maximum range of +/-16.7nT, was displayed as Standard Deviation values clipped to +/-3nT so to clarify the mid-range anomalies.

The magnetic data presented in Figures 5 and 6 was processed as follows: Despike: X radius=1, Y radius=1, Threshold=3.0, Spike replacement=mean Clip: Min=-5, Max=5 Low pass filter: X=1, Y=1, Weighting = Gaussian Interpolate: Direction=Y, Mode=Expand, Expand method=SinX/X

4. RESULTS and DISCUSSION (Figures 3-7, features labelled on Figure 7)

4.1 Results Overall, there is little significant magnetic interference deriving from external influences within the area surveyed (power lines, services etc), and therefore the results give a true representation of sub-surface magnetic variation. The magnitude of background readings across the site varies between about -1.5 and 1.5nT, providing a clear distinction between natural variation and probable anthropogenic features. The results show an array of buried archaeological features, as well as numerous magnetic irregularities which will be outlined first. There are several areas of magnetic disturbance around the perimeter of the areas surveyed and most evidently in the southeast and southwest corners of the survey. The disturbance is predominantly a response to the proximity of the post and wire fence along the southern and western boundaries of the field, as well as the metal gate entering the southwest corner. The response in the southeast corner is less easy to interpret as it is away from the field boundary, but this must identify the presence of buried ferrous scrap. There are numerous low magnitude dipolar readings, up to +/- 16.3nT in range, across the area surveyed that represent either weakly ferrous material or thermoremnant debris buried within the soil. There are other high magnitude dipolar readings that are at the maximum range (+/- 100nT), and which represent modern ferrous scrap. The stronger of these dipolar readings are marked on Figures 10 and 11. There are weak negative trends within the data, broadly oriented southwest-northeast, which are likely to represent variation within the underlying superficial geology. The area of principal archaeological interest is in the southern half of the survey area. Here there are a series of strong and weaker positive linear anomalies which, although discontinuous, appear to form a coherent rectilinear arrangement of gullies or ditches (A and B). It can be suggested that these are only the fragmentary remains of a pattern of small ditched enclosures as there are segments which align perfectly that are broken by a gap in the magnetic anomaly too great to have served as an entranceway (e.g. C, a ‘blank’ of about 24m apart). Differential degrees of truncation are perhaps indicated by the varying magnitude of response of positive linear anomalies in the same feature group. Alternatively some sections of ditch or gully may contain a greater or lesser quantity of magnetically enhanced material within the fill. It is suggested that the positive linear anomaly group most likely represents a pattern of rectilinear enclosure but there is a small chance that these represent foundation trenches or post trenches associated with a range of buildings, though the overall area of the group suggests that this is unlikely. There are a number of positive point anomalies in the vicinity of the proposed enclosures, and the fact that such anomalies are restricted to the same area reinforces

the proposal that this is the focus of the area of archaeological interest. Furthermore, there is a clear circular positive linear anomaly (D), measuring 4.9m across, on the western edge of survey area that is interpreted as a ring gully or ditch associated with a round structure. A second anomaly (E), 19m to the southeast, has similar characteristics but has a weaker magnetic response. A number of dipolar anomalies in the centre of the survey area, to the north of the ditch or gully complex, appear to be grouped in a meaningful cluster (F). The group is arranged in a linear pattern oriented broadly east-west. It is possible that these anomalies represent in situ heating events, such as hearths or ovens, but as the magnitude of the anomalies is not great, it is possible that the responses are a result of ferrous or magnetically-enhanced material within a cut archaeological feature such as trench or segment of ditch. There are three dipolar anomalies (G, H and I) whose character is indicative of a hearth or site of other in situ heating, rather than being associated with buried ferrous material. Lastly, there are a number of slight, yet clear, negative linear anomalies that cross the site on a northwest-southeast axis (J, K and L). These negative anomalies are well-defined and different to the geological trends already described. Negative linear anomalies of this type might be a product of stone-filled land drains or remnants of masonry. The negative linear features are oriented with the gentle slope of the field which, along with the presence of clay soils, might support an interpretation as stone- filled drains. However, two of these features run parallel with each other, 2.3m apart, and this might be considered unusual for land drains (L).

4.2 Discussion Geophysical survey of land to the south of Cloverhayes, Smallridge, Axminster, in East Devon, has revealed a variety of buried archaeological features. The anomalies that are present include a series of positive linear features, whose arrangement suggests the presence of at least one phase of rectilinear enclosure on the ridgetop. The ditches or gullies that these anomalies reflect do not conform to the orientation of the historic landscape nor conform to any of the boundaries shown on historic a map, which implies that they derive from activity of greater antiquity. In addition to these ditches or gullies there are, in the same area, positive anomalies redolent of pits, possible hearths, and two circular anomalies which may represent structural ring gullies. Taken as a whole, it is possible that the survey has revealed a hitherto unknown settlement and enclosure complex of prehistoric, Roman or early medieval date.

5. SIGNIFICANCE

The magnetic survey has demonstrated the existence of archaeological remains within the site, but these are not as significant as they might have been (i.e. a rare Roman camp). The survey was commissioned in order to provide additional information to help clarify whether vegetation marks identified during the Blackdown Hills AONB and East Devon River Catchments NMP Project represented a Roman camp. Unfortunately, as discussed above, there is little within the results of the survey to support this suggestion. Instead, the results show sub-surface features not visible on aerial imagery that are more akin to domestic settlement and enclosure whose date is

unknown. There are no magnetic anomalies that correspond to the proposed vegetation marks, which raise doubts about their validity.

ACKNOWLEDGEMENTS The survey was undertaken by Dr Chris Smart, Dr Joao Fonte, Dr Lukas Holata and Jake Godfrey of the Department of Archaeology, University of Exeter. This report, including illustrations, was prepared by Dr Chris Smart. The project was administered on behalf of the University of Exeter by Dr Chris Smart. The landowners, are thanked for allowing access to the site. Bill Horner and Cain Hegarty administered the work on behalf of Devon County Council and also co-ordinated joint funding with the Blackdown Hills AONB.

REFERENCES

English Heritage 2008: Geophysical Survey in Archaeological Field Evaluation.

Silvester, R.J. and Bidwell, P.T. 1984, ‘A Roman Site at Woodbury, Axminster’, Proceedings of the Devon Archaeological Society 42, 33-57.

Weddell, P.J., Reed, S.J. and Simpson, S.J. 1993, ‘Excavations of the Exeter- Dorchester Roman Road and the Roman Fort Ditch and Settlement at Woodbury near Axminster’, Proceedings of the Devon Archaeological Society 51, 33-133.

APPENDIX 1: Survey grid corner points

Point Id Easting Northing Ortho. Hgt. 1 329879.5192 101102.3835 92.1670 2 329905.9141 101116.7912 92.1014 3 329932.0953 101131.1027 91.3123 4 329958.3918 101145.6442 90.4543 5 329984.6947 101160.0642 88.9746 6 329970.2937 101186.3122 90.3089 7 329943.8362 101171.8763 91.6053 8 329917.6038 101157.4384 92.6204 9 329891.3614 101143.0276 93.4421 10 329865.0523 101128.5695 93.1053 11 329850.5963 101154.9634 94.5103 12 329876.8261 101169.3081 94.7657 13 329903.2320 101183.6981 94.2257 14 329929.4925 101198.1800 93.0480 15 329955.7946 101212.6725 91.5920 16 329941.3471 101238.9630 92.6681 17 329915.1070 101224.4708 94.1751 18 329888.7222 101210.0702 95.3727 19 329862.4479 101195.5825 95.9392 20 329874.3316 101236.2996 96.5757 21 329900.5905 101250.6807 95.3615 22 329926.9125 101265.1917 93.7399 23 329938.7241 101305.9170 93.1903 24 329912.3333 101291.4577 94.7194 26 329886.1052 101277.0122 96.3549

APPENDIX 2: National Grid Reference co-ordinates for fence and gate posts in field surveyed

Point Id Easting Northing Ortho. Code Hgt. 27 329853.0675 101277.9396 98.4203 GATE 28 329842.8610 101142.3298 93.6595 GATE 29 329873.0726 101104.4233 92.3318 GATE 30 329877.4526 101102.2280 92.2927 GATE 31 329878.5551 101102.6520 92.2377 FNCE 32 329884.3459 101096.2471 91.8912 FNCE 33 329891.9475 101090.7615 91.6924 FNCE 34 329900.8012 101093.9051 91.6407 FNCE 35 329908.2072 101099.8104 91.5356 FNCE

36 329916.2585 101106.2673 91.4005 FNCE 37 329923.7159 101112.4478 91.1911 FNCE 38 329930.5952 101118.4651 91.2378 FNCE 39 329937.4588 101124.9784 91.1075 FNCE 40 329945.0954 101132.2623 90.8779 FNCE 41 329951.6270 101138.4562 90.6719 FNCE 42 329958.9614 101145.9037 90.3985 FNCE 43 329965.4645 101147.4571 90.0301 FNCE 44 329973.7231 101148.7321 89.6200 FNCE 45 329982.3336 101150.3017 89.1640 FNCE 46 329991.0097 101152.5191 88.6247 FNCE 47 329999.2157 101153.6090 88.0323 FNCE 48 330014.3306 101155.8284 87.1783 FNCE 49 330010.8334 101164.9104 87.3443 FNCE 50 330005.9376 101173.6771 87.6688 FNCE 51 330004.1426 101179.5574 87.9011 FNCE 52 330006.2493 101191.2481 87.8331 FNCE 53 329997.0918 101199.0444 88.5823 FNCE 54 329992.2385 101204.9897 89.0073 FNCE 55 329986.9206 101213.2017 89.5634 FNCE 56 329982.8795 101219.6896 89.9627 FNCE 57 329978.7067 101226.3156 90.2951 FNCE 58 329974.5647 101233.5931 90.5923 FNCE 59 329970.1074 101240.5073 90.9524 FNCE 60 329965.6461 101247.6110 91.1109 FNCE 61 329961.3615 101254.1574 91.3823 FNCE 62 329956.6752 101261.2308 91.7377 FNCE 63 329952.1120 101268.6695 92.1037 FNCE 64 329947.8404 101276.4698 92.4013 FNCE 65 329945.4049 101284.7192 92.7683 FNCE 66 329943.2812 101291.8957 92.9902 FNCE 67 329941.4284 101299.8363 93.1469 FNCE 68 329940.3366 101307.7085 93.1699 FNCE 69 329939.8982 101316.2243 93.1993 FNCE

0 1 2km

Figure 1. Location of survey at Cloverhayes, Smallridge, East Devon (© Crown Copyright and Database Right (2017). Ordnance Survey (Digimap Licence)). Figure 2a. 1838 Axminster tithe map, showing former subdivision of the site.

Figure 2b. 1890 Ordnance Survey 1st ed. 25” to 1 mile (© Crown Copyright and Landmark Information Group (2017). All rights reserved. (1890)). Figure 2c. 1905 Ordnance Survey 1st ed. 25” to 1 mile first revision (© Crown Copyright and Landmark Information Group (2017). All rights reserved. (1905)).

10.589.12 40121.478.837.60 nT nT 7.076.08 5.324.56 .000000 .000000 3.563.04 1.801.53

101300 0.050.01 nT 101300 -1.71-1.51 -3.46-3.03 -3 0 3 -5.22-4.55S.D. -6.97-6.07 -8.73-7.59 -10.49-9.10

-3 0 3 S.D. .000000 .000000 101200 101200 .000000 .000000 101100 101100 0 50 100m

329800.000000 329900.000000 330000.000000

Key to magnetic anomaly types Figure 3. Greyscale plot of raw data (©postive Crown point Copyright and Databasenegative Right (2017). linear Ordnance Survey (Digimaparea of magnetic Licence)). interference

postive linear dipolar (archaeological)

weak positive linear dipolar (modern ferrous) 329800.000000 329900.000000 330000.000000

10.589.12 40121.478.837.60 nT nT 7.076.08 5.324.56 .000000 .000000 3.563.04 1.801.53

101300 0.050.01 nT 101300 -1.71-1.51 -3.46-3.03 -3 0 3 -5.22-4.55S.D. -6.97-6.07 -8.73-7.59 -10.49-9.10

-3 0 3 S.D. .000000 .000000 101200 101200 .000000 .000000 101100 101100 0 50 100m

329800.000000 329900.000000 330000.000000

Key to magnetic anomaly types Figure 3.4. TraceGreyscale plot plotof raw of dataraw data (©postive Crown point Copyright and Databasenegative Right (2017). linear Ordnance Survey (Digimaparea of magnetic Licence)). interference

postive linear dipolar (archaeological)

weak positive linear dipolar (modern ferrous) 329800.000000 329900.000000 330000.000000

10.589.12 40121.478.837.60 nT nT 7.076.08 5.324.56 .000000 .000000 3.563.04 1.801.53

101300 0.050.01 nT 101300 -1.71-1.51 -3.46-3.03 -3 0 3 -5.22-4.55S.D. -6.97-6.07 -8.73-7.59 -10.49-9.10

G K J F -3 0 3 L S.D. H .000000 .000000 101200 101200 C A

I B D E .000000 .000000 101100 101100 0 50 100m

329800.000000 329900.000000 330000.000000

Key to magnetic anomaly types Figure 3.5.4.6. TraceGreyscale plot plotof rawprocessed of datarawprocessed data data data (©postive Crown point Copyright and Databasenegative Right (2017). linear Ordnance Survey (Digimaparea of magnetic Licence)). interference

postive linear dipolar (archaeological)

weak positive linear dipolar (modern ferrous)

10.589.12 40121.478.837.60 nT nT 7.076.08 5.324.56 .000000 .000000 3.563.04 1.801.53

101300 0.050.01 nT 101300 -1.71-1.51 -3.46-3.03 -3 0 3 -5.22-4.55S.D. -6.97-6.07 -8.73-7.59 -10.49-9.10

-3 0 3 S.D. .000000 .000000 101200 101200 .000000 .000000 101100 101100 0 50 100m

329800.000000 329900.000000 330000.000000

postive linear dipolar (archaeological)

weak positive linear dipolar (modern ferrous) 329800.000000 329900.000000 330000.000000

10.589.12 40121.478.837.60 nT nT 7.076.08 5.324.56 .000000 .000000 3.563.04 1.801.53

101300 0.050.01 nT 101300 -1.71-1.51 -3.46-3.03 -3 0 3 -5.22-4.55S.D. -6.97-6.07 -8.73-7.59 -10.49-9.10

G K J F -3 0 3 L S.D. H .000000 .000000 101200 101200 C A

I B D E .000000 .000000 101100 101100 0 50 100m

329800.000000 329900.000000 330000.000000

postive linear dipolar (archaeological)

weak positive linear dipolar (modern ferrous)