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FOXHALL ROAD, IPSWICH A RE-INVESTIGATION AND RE-ASSESSMENT OF AN ARCHAEOLOGICAL SITE P. ALLEN, D. BRIDGLAND, A. HAGGART, J-L. SCHWENNINGER, M. WHITE and D. WILSON Abstract New investigations at this important locality in 2005 indicated that humans occupied a favoured lakeside locale in the upper Mill River valley about 425,000 years ago during the transition from the Anglian glacial period to the Hoxnian temperate period. Background The site lies in the eastern part of Ipswich, on the south side of Foxhall Road, centred on TM186440, at about 35 m O.D., sitting in a shallow valley forming the upper part of the Mill River drainage system. The site was originally worked on by Layard (1903–1905) (Fig. 1), Smith (1914) and Moir (1921) and the results reported in Layard (1902, 1903, 1904, 1906a, b), Smith (1921) and Boswell & Moir (1923). This work was summarised by Wymer (1985) and re-appraised in detail by White & Plunkett (2004). The site was redeveloped in 2005 by Barratt Homes who commissioned and funded an investigation of the early archaeological work, which was carried out by the Essex County Council Field Archaeology Unit. The study involved using literature and maps of the period when the excavations were carried out. This was followed up by using borehole and trial pit information, including analyses of samples collected from the site in 2005. Geological Background The surface landscape of eastern Suffolk comprises a series of flat plateau-like elements, thought to be underlain by glacial gravel (e.g. Boswell, 1913; 1931), but Rose & Allen (1977) redefined them in part as early Thames gravels of the Kesgrave Formation. Mathers et al. (2007) showed the glacial gravel to have a lobe-like distribution spreading out from the Gipping Valley at Ipswich, possibly as a pro-glacial outwash fan. Site Geology At the site, a borehole sunk by Layard proved till at a depth of 8·5 m below the ground surface at least one metre thick; it was not bottomed. From examination of the till and the sands and gravels above, Layard (1904, 1906b) and Boswell (1931) listed fossils (Gryphea and Belemnites) and erratics (Chalk, Red Chalk, Jurassic oolite and volcanic tuff) which are characteristic of the Anglian glaciogenic material. Layard (1906b) also noted the presence of striated flint and that one face of the oolite had been smoothed by abrasion to show sections through the oolites. Within the heavy mineral suite (Boswell & Moir, 1923), a number of ‘softer’ heavy minerals occur, such as kyanite and apatite. Such material is absent from earlier deposits and some is sufficiently fragile that it rarely survives reworking into younger deposits in any quantity. Above this is brickearth, predominantly a silty-clay or sandy-silty-clay, with fine to medium sand or even gravel interbeds (Boswell & Moir, 1923). The brickearth reflects deposition in quiet water, such as a lake. This, in turn is overlain by sands and gravels, often clay-rich or interbedded with the upper
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Figure 1. Layard’s Foxhall Road site at the end of the 1904–1905 season. (Reproduced by permission of Suffolk Record Office, Ipswich Branch). part of the brickearth. These sands and gravels appear to fall into two units (Fig. 1). From c. 2 m below the ground surface, the beds of the lower unit, are dipping, with reactivation surfaces and minor slumping, suggesting formation of a delta. The beds of the upper unit are horizontal and often geologically disturbed in their uppermost 1–2 m. From geomorphological field mapping, Allen (in Allen & White, 2004) showed that the deposits lay within a shallow valley, now dry, that formerly was the headwaters of the Mill River. This confirms the proposed existence of such a river by Smith (1921). Houses on the brickearth outcrop at Starfield Close, the site of a former brickpit, lie significantly below the surrounding valley bottom, suggesting a deepened section. From Layard’s borehole, the deposits at Foxhall Road also lie in a channel, at least 9·5 m deep. Whilst this is minor compared to some of the sub-glacial scouring in the major valleys (Woodland, 1970), for example such as that by the Orwell Bridge (Fletcher & Nicholls, 1984), it is still considerable and certainly more than would be expected in a fluvial system. The brickearth outcrops appear to reflect the presence of lakes in overdeepened sections of the valley. Such an irregular long profile, with till in at least one of the over-deepened sections, would be in keeping with sub-glacial formation by scouring. The relationship of this scouring phase to the formation of the fan requires further consideration. Possibly there was a short-lived ice advance over the fan.
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Figure 2.Foxhall Road; site of the Valley Brick Works (reproduced with kind permission from Ordnance Survey, 2nd Edition, 1904).
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A local Ordnance Survey map, dated 1904, showed the worked area of the brickpit (Fig. 2), reflecting the shape of the lake in which the brickearth was deposited. There is an irregular narrower extension to the north-west, towards the area of the archaeological excavations. The implication of this is that there was a narrow extension of the brickearth, hence also the lake, in that direction, possibly along the feeder stream/river. A similar alignment was proposed by Smith (1921). The delta structure would be in keeping with a minor delta building out from the feeder stream into the deep ‘brickearth lake’. 2005 Stratigraphic Investigations and Interpretation No vertebrate or pollen material was recovered. Clast lithology. Stone counts showed comparable lithologies (flint dominant, quartz and quartzite common, minor amounts of chert and sandstone) as the Kesgrave gravels, but the dominant angularity of the flint was more in keeping with the local glacial outwash or counts from smaller rivers in East Anglia. Ostracods. Only two ostracods were identified, subject to confirmation, Ilyocypris cf. decipiens and Cyclocypris serena. The two species have slightly different living conditions. Today, both species are often found in water bodies where the main substrates are silts and sands and are associated with cold climatic conditions. Luminescence dating. Two samples were selected for optically stimulated luminescence (OSL) dating, giving a range of 416,000–434,000. A date of 400,000+ BP, late Anglian or early Hoxnian, supports the interpretation of the sediments as being deposited in a recently deglaciated, post-Anglian landscape. Archaeology Two new artefacts were recovered from spoil during the recent investigations, a handaxe and a simple core. The morphology and condition of the handaxe fits comfortably with those recovered by Layard, Moir and Smith in their respective excavations; it could feasibly have been derived from any of the original artefact-bearing deposits. The core is also very similar to those from earlier excavations, having been minimally worked on a small pebble. One trench was deliberately aligned to intersect with the earlier archaeological work and successfully located part of Smith’s 1914 excavations, suggesting that the relative positions of the earlier excavations suggested by White & Plunkett were about right. Results/Outcomes 1. The upper parts of the stratigraphies of Layard, Smith and Boswell have been identified and are confirmed. 2. The site of Smith’s excavation is now known with precision and the other early sites can be located with the minimum of trial-and-error investigation. 3. The evolution of the palaeogeographies of the lake in which the brickearth accumulated and the area of human activity are now better understood. 4. A late Anglian/early Hoxnian date is indicated by the OSL dating and strongly supported by the heavy minerals analysis. Other lines of evidence (palaeogeographical reconstructions, ostracods, artefacts) are in keeping with this dating. Both the recent re-mapping by the British Geological Survey (Mathers et al., 2007) and the roundness/angularity characteristics of the gravel argue against it being part of the Kesgrave gravels, again suggesting an Anglian or later date.
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References Boswell, P. G. H. (1913). The age of the Suffolk Valleys. Quarterly Journal of the Geological Society of London 69: 581–620. Boswell, P. G. H. (1931). The stratigraphy of the glacial deposits of East Anglia in relation to early man. Proceedings of the Geologists’ Association 42: 87–111. Boswell, P. G. H. & Moir, J. R. (1923). The Pleistocene deposits and their contained Palaeolithic implements at Foxhall Road, Ipswich. Journal of the Anthropological Institute 53: 229–263. Fletcher, M. S. & Nicholls, R. A. (1984). A buried valley in the Orwell estuary. Quarterly Journal of Engineering Geology 17: 283–288. Layard, N. F. (1902). Palaeolithic implements in Ipswich. Nature 66: 77. Layard, N. F. (1903). A recent discovery of Palaeolithic implements in Ipswich. Journal of the Anthropological Institute 33: 41–43. Layard, N. F. (1904). Further excavations on a Palaeolithic site in Ipswich. Journal of the Anthropological Institute 34: 306–310. Layard, N. F. (1906a). A winter’s work on the Ipswich Palaeolithic site. Journal of the Anthropological Institute 36: 233–236. Layard, N. F. (1906b). Account of a Palaeolithic site in Ipswich. Proceedings and Communications of the Cambridge Antiquarian Society 11: 493–502. Mathers, S. J., Woods, M. A. & Smith, N. J. P. (2007). Geology of the Ipswich district – a brief explanation of the geological map. Sheet Explanation of the British Geological Survey. 1:50,000 Sheet 207 Ipswich (England and Wales). Rose, J. & Allen, P. (1977). Middle Pleistocene stratigraphy in south-east Suffolk. Journal of the Geological Society of London 133: 85–102. Smith, R. A. (1921). Implements from plateau brickearths at Ipswich. Proceedings of the Geologists’ Association 32: 1–16. White, M. & Plunkett, S. (2004) Miss Layard Excavates: A Palaeolithic Site at Foxhall Road, Ipswich, 1903–1905. Western Academic and Specialist Press Ltd, Liverpool. 196 pp. Wymer, J. J. (1985) Palaeolithic Sites of East Anglia. Geobooks, Norwich. 440 pp. P. Allen Department of Geography, Royal Holloway University of London D. Bridgland Department of Geography, University of Durham A. Haggart D. Wilson School of Science, University of Greenwich J-L. Schwenninger Research Laboratory for Archaeology and the History of Art, University of Oxford M. White Department of Archaeology, University of Durham
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