Investigating the Palaeolithic Potential of Regional Landscapes: a case study from the Trent Valley

Andy J. Howard1, David R. Bridgland2, Mark J. White3 and Tom S. White4

1
Landscape Research and Management
2Department of Geography, Durham University
3Department of Archaeology, Durham University
4Natural History Museum

Executive Summary

Trent Valley: regional desk-based and field investigation of river terrace and alluvial deposits

This case-study is not an account of a specific site investigation; instead it describes a methodological approach and sets out a task list that can be used to assess the Palaeolithic potential of regional landscapes. It is applicable where archaeology may be known, but also poorly understood in terms of the origin, age and distribution of the sediments in which cultural and palaeoenvironmental remains might be preserved.

The methodology, which combines elements of desk-based assessment and fieldwork, was developed for the Trent Valley Palaeolithic Project and key results are presented to demonstrate how the regional knowledge base was advanced through this study. Whilst the methodological approach was developed and funded as a research study, it could be adapted for use in commercial archaeology interventions required as part of any local authority planning process.

Keywords

Where: Trent Valley
Region: East Midlands & East Anglia
Palaeolithic period(s): All Palaeolithic (pre-Anglian to Holocene)
Type of investigation: Regional evaluation
Methods: Boreholes; Desk-based; Field visits to quarries and other exposures
Type(s) of deposit: River terrace deposits; Glacial deposits
Features of interest: Regional study; Impact of glaciation on river drainage pattern

Project stages

  • Desk based assessment
  • Geotechnical/geoarchaeological survey
  • Literature/mapping review (DBA)
  • Test pitting/Borehole survey
  • Test pitting/boreholes
  • Post-excavation assessment (and reporting)
  • Post-excavation analysis (and reporting)
  • Final Report
  • Deposit with HER and museum (and Oasis)
  • Publication (academic and/or public)

‘The Lower and Middle Palaeolithic occupation of the Middle and Lower Trent Catchment and adjacent areas, as recorded in the river gravels used as aggregate resources’ was undertaken as a research project funded by the Aggregates Levy Sustainability Fund (ALSF Project 3495).

Data collection, including fieldwork, was undertaken between 2005 and 2007 with post-excavation completed in 2008. The results were published in a variety of journal articles, as well as a Field Guide of the Quaternary Research Association (White et al. 2007) and monograph (Bridgland et al. 2014).

Development Context

The development of methodologies for investigating discrete sites are covered amply by a range of contributions in this guidance. However, often heritage professionals are asked to assess, or seek to understand the Palaeolithic potential of bigger landscape blocks; in such cases, whilst lithic material may be known from the area, the finds may be poorly constrained, with little or nothing known about their geographical, stratigraphic or paleoenvironmental setting.

With funding from the ALSF, the Trent Valley Palaeolithic Project (TVPP) was undertaken to enhance archaeological knowledge of the main river and its tributaries, including former drainage networks across Staffordshire, Derbyshire, Leicestershire, Nottinghamshire and Lincolnshire.

The aim of this case study is to demonstrate the methodological approach used to investigate this large landscape and consider how the results provide insights that aid the management of the Palaeolithic resource.

Archaeological Context

Before the Aggregates Levy project, a long history of archaeological investigation in the valleys of the Trent and its tributaries (Figure 1) had resulted in sizable collections of lithic material spread across several museums (Posnansky 1963; White et al. 2009); whilst key historic hotspots of artefact recovery were known, for example around Etwall, Hilton and Willington in the middle Trent valley, the age and context of the finds were not clearly understood and, prior to the Aggregates Levy project, were based on a relatively simplistic 3-stage model of river terrace development (Figure 2) that had been established over 40 years previously (Clayton 1953; Posnansky 1960; Howard et al. 2007).

Furthermore, knowledge of the recovered artefact assemblages around Etwall, Hilton and Willington was complicated since sands and gravels from a number of quarried deposits were processed historically at a single locality, leading to the mixing of palaeoliths from stratigraphically discrete deposits (White et al. 2009).

More recent work on British river systems further south, such as the Thames (Bridgland 1994), Severn-Avon (Maddy et al. 1991, 1995) and palaeo-Solent (Westaway et al. 2006), suggested that the sequence of superficial deposits and associated Palaeolithic remains within the Trent Valley was probably more complex than hitherto considered.

Furthermore, in contrast to these more southerly systems, two other factors added to the potential complexity of Palaeolithic knowledge within the Trent catchment:

(1) it was long suspected that the area may have been impacted by an ice sheet incursion in a post-Anglian (MIS 12)–pre-Late Devensian (MIS 2) cold stage (Straw 1983) resulting in the reworking of artefacts and sediments;

(2) in southern river systems, flint is the most commonly found lithic material reflecting its availability in local bedrock resources, but in the Midlands, it does not crop out naturally and therefore local bedrock resources such as quartzite may have been exploited for toolmaking, a factor which may have been overlooked by antiquarian collectors (White et al. 2009).

Methodology & Research Questions

The TVPP investigated the archaeological record by completion of a number of tasks, undertaken as discrete work packages, with each one informing the next stage of investigation (Table 1).

With each task, it is essential to be aware of the potential shortfalls of the associated datasets and the limitations of the approach, which are summarised. Whilst the TVPP was undertaken with research funding and comprised elements that might be considered to reflect both desk-based assessment (DBA) and fieldwork (FW), a significant enhancement of Palaeolithic knowledge for any region can be achieved by working through the steps sequentially.

Furthermore, once a baseline framework of Palaeolithic knowledge is in place, fieldwork (Table 1: Task 9), could be built into the developer-funded applications via the tendering process and Written Schemes of Investigation (WSIs), as suitable opportunities arise.

Table 1: The investigation of the Palaeolithic potential of regional landscapes: a task list used in the TVPP. Tasks that can be completed by desk-based assessment are annotated DBA; those involving fieldwork are annotated FW

TaskDescriptionSource of InformationPotential Issues for the Heritage Investigator
1 (DBA)Identify all known find spots and the location of any archaeological collectionsCounty-based Historic Environment Records, museum catalogues, private individuals. Published Quaternary geological and archaeological literature in national and local journals, geological memoirs, field guides of the Quaternary Research Association, academic theses etcKnown Palaeolithic finds will invariably only represent a partial record of actual resource. Geographic location and any stratigraphic information of find spots may be poor, or unknown. Initial desk-based assessment may provide little detail of artefact condition and hence taphonomic history. Spatial distribution of known finds may be biased by a number of factors (land-use, collector focus, ubiquity of exposure etc). Variable input of modern information to HERs (notably by academic investigators and private collectors)
2 (DBA)Compare find spots to the geological record of mapped deposits to identify any initial spatial patterns (presence/absence, apparent hotspots and/or blank areas)Mapping of the British Geological Survey (BGS). Quaternary geology literatureBGS mapping is of very high quality but it should never be considered as a definitive record of superficial deposits. Unless subject to revision, a significant corpus of mapping is based on survey during the early 20th century when less emphasis may have been placed on the importance of recognising superficial sediments, especially if less than 1m in thickness.
3 (DBA)Establish initial hypotheses for the potential of Palaeolithic archaeology in the region
4 (DBA & FW)Review artefact collections to determine typology, material type, condition and probable ageArtefact collections in museums and possibly private ownershipLack of time and financial resource to review material. Loss/misplacement of material in museums and private collections
5 (DBA)Review of information concerning geological deposits; this should include any associated palaeobiological records (pollen, molluscs, insects, plant remains, large and small vertebrate remains etc) and absolute and/or relative dating evidence. This review will allow probable age of sediments, mode of deposition and palaeoclimate to be characterisedReview of published Quaternary geological and archaeological literature in national and local journals, geological memoirs, field guides of the Quaternary Research Association, academic theses etcCost of access to key literature held in specialist journals. Lack of information and/or ambiguity in the geological evidence prevent confident interpretations
6 (DBA)Construct model of geological landscape evolution and human activity (presence/absence). Compare artefact records (typology) with geological records to determine confidence of age assignations and security of context interpretationsInformation generated by completion of tasks 4 and 5Confidence of interpretations
7 (DBA)Seek to understand patterns of Palaeolithic activity and critically review known resource (presence/absence) in the light of current knowledge of landscape evolution, taphonomic processes etcInformation generated by completion of tasks 4, 5 and 6Confidence of interpretations
8 (DBA)Revise hypotheses for the potential of Palaeolithic archaeology in the region
9 (FW)Verify models of landscape evolution and archaeological potential through new fieldwork focused on key geological units. The aim of this fieldwork would be to collect new empirical data that elucidate the provenance, age, palaeoenvironments and stratigraphic relationships of key deposits.New fieldworkIf linked to the development process and commercial funding, opportunities may not arise in areas near well-known sites that might provide the greatest potential to generate new data

When investigating the Palaeolithic, it is important that any investigation is not focused solely on the cultural record (i.e. lithics), but that equal emphasis is placed on the environmental deposits. Not only can these palaeobiological remains provide proxy information of past climate, floral and faunal histories, and landscape evolution, some elements can provide opportunities for absolute dating and the establishment of a chronological framework.

Empirical evidence from across midland and southern England demonstrates that the majority of Palaeolithic artefact assemblages are associated with, and recovered from, river terrace sands and gravels, a correlation reflecting a number of key factors: (1) the focus of early human activity within these corridors that would have been rich in natural resources; (2) the capacity of any river to act as a natural sediment trap and conveyor of archaeological remains; (3) the economic importance of sand and gravel extraction and hence the long history of sediment exposure; and (4) the long period of manual extraction, until at least the 1930s, which provided significant opportunities for the discovery of remains, particularly artefacts.

However, it is important to stress that river terraces do not represent the only contexts in which Palaeolithic remains might be discovered and, when investigating any large area of landscape, it is essential to start by considering the potential of the entire sedimentary sequence, as well as landscape evolution and the processes and environments under which the sediments were emplaced: for example, glacial, periglacial, fluvial, lacustrine, aeolian, and mass-movement.

Furthermore, as an investigator, it is important to recognise that geological processes are not static, but are part of a spatial and temporal continuum of landscape evolution comprising sediment erosion, deposition and periods of temporary storage. Any Palaeolithic archaeology associated with this continuum of processes will be subject to the same conditions. For example, artefacts might be discarded and preserved on a floodplain surface during an interglacial, but reworked by glacial or meltwater processes during a subsequent cold stage; by the time they are recovered by the archaeologist, they may have been reworked several times over.

For the heritage professional, the starting point for any division of geological deposits within a region is the mapping of the British Geological Survey (BGS). Whilst the quality of this dataset is extremely high, it is important to recognise that it should never be considered to be a definitive product for either the spatial distribution of deposits or their processes of formation. For example, older maps often identify isolated patches of ‘glacial sand and gravel’, though their precise origin may be unclear; detailed analysis might show that they are river terrace sediments, which would have a higher potential for the preservation of Palaeolithic archaeology.

The TVPP used baseline mapping of the BGS as the starting point for investigations but it also utilised a number of other techniques to enhance field mapping. Notably, clast lithological analysis was used to determine the composition and provenance of gravels and, together with morphostratigraphy, helped to distinguish key superficial units (river terrace sediments and patches of glacial outwash).

Results & Significance

Key project results and their wider significance are summarised in Table 2.

Table 2: Key events identified by the TVPP and their significant implications for the management of the Palaeolithic resource

Key Results of the TVPPImplications for Management and Prospection of Palaeolithic Resources
Prior to the Anglian glaciation of MIS 12, the drainage network of the East Midlands was radically different and the river Trent did not exist. Instead eastward drainage was most probably associated with another river that flowed via the Ancaster Gap (Ancaster River) whilst the future headwaters of the Trent drained into forerunners of the Derwent (Derby River) and Dove (Hinkley River) flowing southwards to join the Bytham River System.Present-day drainage configuration will be of little help in identifying potential sediments and sites of Lower Palaeolithic remains. The emphasis for prospection needs to be placed upon deposits thought to be associated with this early course and palaeogeography.

By destroying the early drainage configuration, the Anglian glaciation would have had a significant impact on the preservation potential of any earlier cultural and environmental archaeological remains associated with the Cromerian Complex (MIS 13–21). It is unlikely that any such remains will be preserved near the surface, though they may be preserved in deeply buried palaeovalleys.
After the Anglian glaciation (MIS 12), the major tributary arms of the Trent system (the Dove, Derwent and Soar) established a drainage network as far as Newark that would be broadly recognisable in the present today. Downstream from Newark, the river drained to the North Sea via the gap in the Jurassic escarpment at Lincoln and along the present-day valley of the River Witham, which at that time was part of the Trent system. Fragments of river terraces at progressively lower altitudes demonstrate that this course was active until the end of the last glacial stage, the Late Devensian (MIS 2).

However, the altitudinal and stratigraphic relationship of glacial sediments to key river terrace sediments where palaeobiological remains are preserved suggest that an ice sheet developed across the region during MIS 8, though its precise extent is unknown.
Whilst progressive incision and aggradation of the river over glacial-interglacial cycles might be expected to preserve Palaeolithic remains throughout this extended period of time, the incursion of glacial ice during MIS 8 would have led to the reworking of older superficial deposits and any archaeological remains associated with them; this may include cultural and environmental materials. Notably, no palaeoenvironmental deposits indicative of the Purfleet and Hoxnian interglacials. (MIS 9 and 11 respectively) are known from the region and the lithic remains within museum collections are not considered fresh, supporting the hypothesis for the lack of primary contexts. Following deglaciation, uninterrupted cycles of river incision and aggradation has led to the development of at least 5 river terraces and associated deposits and these have the potential to include preservation in primary contexts, although recycling of archaeological remains with time will still provide the majority of Palaeolithic remains.
The majority of artefacts recovered are made of flint, though this cannot be sourced locally from the bedrock geology. However, a significant number of artefacts are quartzite, which was probably derived as cobbles from within the Triassic bedrock in parts of the catchment though it is also an abundant component of glacial and fluvial sands and gravels. Analysis of collections indicates that the majority of artefacts are abraded.The majority of artefacts are likely to be reworked and in secondary contexts, even if found as clusters of lithics.

Greater emphasis needs to be placed on identifying non-flint lithic remains made from local quartzite and other rock types (e.g. andesite), which may have been overlooked by past collection strategies.

Key Insights

The TVPP identified a number of key events and associated observations that provide significant insights in the history of the region and, in turn, the management of Palaeolithic resources and geoprospection (Table 2; Figures 3–5).

The project was a collaborative effort between Palaeolithic archaeologists (MJW, TSW) and Quaternary geologists (DRB, AJH) and such joint expertise is essential to maximise the potential of Palaeolithic research since the deposits are usually highly fragmentary and part of a complex depositional framework.

Whilst the TVPP was undertaken as research over a concentrated timescale, there is no reason why the key tasks used to elucidate landscape history and human habitation could not be undertaken in a more piecemeal fashion, by way of developer-funded opportunities.

In many ways, commercial archaeology now offers the most opportunities to undertake new, high-value Palaeolithic research since academic specialists can often face challenges accessing active quarries to record exposures and/or collect material. It is therefore important that academic specialists work closely with colleagues undertaking commercial projects as opportunities arise.

Such collaboration with the commercial sector also ensures that the results of academic research are likely to be disseminated to local Historic Environment Records via initiatives such as OASIS.

Acknowledgements

The Trent Valley Palaeolithic Project was ALSF Project 3495 (Full name: The Lower and Middle Palaeolithic occupation of the Middle and Lower Trent Catchment and adjacent areas, as recorded in the river gravels used as aggregate resources: awarded to M.J. White, D.R. Bridgland and A.J. Howard and employing T.S. White).

The support of the quarry companies and landowners of the Trent Valley, who generously provided access to land and exposures, is gratefully acknowledged.

References

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Bridgland, D.R., Howard, A.J., White, M.J. and White, T.S. 2014. 'Quaternary of the Trent'. Oxbow Books: Oxford.

Clayton, K.M. 1953. 'The glacial chronology of part of the middle Trent Basin'. Proceedings of the Geologists’ Association 64: 198–207.

Howard, A.J., Bridgland, D., Knight, D., McNabb, J., Rose, J., Schreve, D., Westaway, R., White, M.J. and White, T.S. 2007. 'The British Pleistocene fluvial archive: East Midlands drainage evolution and human occupation in the context of the British and NW European record'. Quaternary Science Reviews 26: 2724–2737.

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Posnansky, M. 1963. 'The Lower and Middle Palaeolithic industries of the English East Midlands'. Proceedings of the Prehistoric Society 29: 357–394.

Straw, A. 1983. 'Pre-Devensian glaciation of Lincolnshire (Eastern England) and adjacent areas'. Quaternary Science Reviews 2: 239–260.

Westaway, R., Bridgland, D. and White, M. 2006. 'The Quaternary uplift history of central southern England: evidence from the terraces of the Solent River system and nearby raised beaches'. Quaternary Science Reviews 25: 2212–2250.

White, T.S., White, M.J., Bridgland, D.R. and Howard, A.J. 2009. 'Palaeolithic and Quaternary research in the Trent Valley (UK): contributions by early collectors'. Proceedings of the Geologists’ Association 120: 223–232.

White, T.S., Bridgland, D.R., Howard, A.J., White, M.J. 2007. 'The Quaternary of the Trent Valley and adjoining regions field guide'. Quaternary Research Association: London.