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The Archaeology of sand landscapes: looking for an integrated approach David Griffiths University of Oxford Scottish Archaeological Internet Report 48, 2011 www.sair.org.uk CONTENTS List of Illustrations. 12 1 The Archaeology of Sand Landscapes: Looking for an Integrated Approach . 13 2 References. 22 11 LIST OF ILLUSTRATIONS 1. Map: Bay of Skaill, Sandwick Parish, Orkney . 1 2. Magnetometer survey on north side of Skaill Bay, 2003–06. 17 3. Mound of Snusgar: topographic survey model (viewed as from SE). 18 4. Magnetometer survey near Skara Brae, 2003 . 20 1 THE ARCHAEOLOGY OF SAND landscapes: looking FOR AN integrated APPROACH The coastal dune systems and semi-stabilised Dundrum, Co. Down (Collins 192, 199). The style machair of Scotland represent a vast but still largely of the time was to treat archaeological exposures in unquantified archaeological and palaeoenvironmen- sand as discrete sites and to excavate them using tal resource. They are an inherently fragile, unstable standard terrestrial techniques – there being as yet and changing environment and therefore highly little understanding of the effects on archaeologi- susceptible to erosion, providing a significant man- cal material of the mechanisms of post-depositional agement dilemma for curatorial authorities. Few change in this type of environment. The very fact such landscapes, even in the wider context of Britain that erosion and dune deflation provided the and Ireland, have yet been subjected to anything main means of identifying deposits which were like a comprehensive characterisation study, encom- subsequently investigated, means that the associ- passing prospection, sampling and investigation, ated data-capture was severely affected by in situ resulting in well-informed selective preservation or destruction, migration and turbation of deposits. mitigation strategies. Practical problems encoun- Associations of artefact and stratigraphic context tered during traditional excavation such as dune are therefore potentially suspect, and furthermore, instability and deflation, deep and unstable sand many radiocarbon determinations, particularly from overburdens and the consequent danger of breaking the earlier decades of this technique, are affected by up stabilising ground cover and accelerating growing doubts over the Marine Reservoir Effect erosion, have meant that we have remained largely and other distorting factors (Ascough et al 2004). dependent on chance exposures to determine the Consequently, through no fault of the excavators, extent of archaeological features and therefore of these interventions must generally be regarded as any intervention. However, increasing utility, ver- providing less reliable and complete a record than satility and affordability in combined prospection many contemporary interventions on ‘solid ground’. methods have begun to point towards new ways Therefore, the broad approach in the less recent forward in tackling this type of landscape. past to these types of landscape could be characterised as: My own interest in sand landscapes was initially sparked some years ago by an aspect of my PhD • ad hoc research on Early Historic coastal trade and set- • reactive to erosion tlement (Griffiths 1992) which brought together a • responsive to in situ exposures of visible surprising number of antiquarian, and also more contexts leading to small-scale rescue or salvage recent, reports of stray finds of artefacts in coastal excavation sand dune areas in the Irish Sea Region and in • often dealing with already severely compro- Atlantic Scotland and Ireland (see also Griffiths mised deposits forthcoming 2009). These vary considerably in date, • focused on finds retrieval detail and apparent quality, but a common factor is the presence in close proximity of ceramic, lithic or By the 1970s, growing acknowledgement of the metalwork material from widely differing periods, limitations of a site-specific approach, coupled with often from the Neolithic or Bronze Age together realisation of the potential for reconstructing past with Early Historic or Medieval objects. Examples landscapes and environments, led to a broadening of include the Culbin Sands, Moray (Black 1891), and approaches encompassing more systematic survey Stevenston Sands, Ayrshire (Callander 1933). A and observation, selective excavation and pal- further extremely important and rich site of this type aeoenvironmental sampling, combined with more is Meols, Wirral, north-west England (Hume 1863; sustained and balanced radiocarbon programmes. Travis 1922; Kenna 1986; Griffiths 2001; Griffiths et A significant example of progress in tackling the al 2007). Pre-twentieth and early twentieth-century archaeology of sand landscapes is the work of Trevor reports are characterised by little or no contextual Cowie and others at Torr’s Warren, Luce Sands in information, concentrating exclusively, or almost Galloway (Cowie 1997). This landscape, character- exclusively, on describing the artefacts themselves. ised today by a vast, and now largely stable dune By the mid 20th century, chance discoveries of system, is one of the most archaeologically tanta- artefacts began to be accompanied by small-scale lising and intractable in Scotland, having produced excavation, often revealing spreads of occupa- over the decades at least 8,000 artefacts of pre- tion debris, hearths and middens, cultivation soils historic, Roman and Medieval date. Yet years of and ard-marks, and even occasionally fragments faithful and determined observation and collecting of buildings, such as at Luce Sands, Galloway by a handful of devoted local archaeologists had (Davidson 192, Jope 199), and Murlough Dunes, not succeeded in establishing a coherent overall 13 context for these objects, despite the occasional Sheffield University in 1988 in the southern islands discovery of individual structures and burials. The of the Western Isles. Its adequacy as a model for work of the Central Excavation Unit in 1977–79, future approaches is discussed below. An account led by Cowie, was confined to a development area and bibliography of this project is provided in these of 7 hectares within a dune landscape of over proceedings (Parker Pearson et al). 1,200 hectares. However, the sample covered by One important conclusion which flows from studies the investigation (approximately 6.2%) was large at these sites, and a range of other recent fieldwork enough to begin to create a true landscape perspec- (see elsewhere below), is that humans have actively tive. Machine-clearing of overburdens of up to 1m modified this type of landscape in the past. The in depth allowed the excavation of buried palae- build-ups of soil forming ancient land surfaces now osols which had been exposed in section by dune buried within dune sequences are not always by- deflation and blow-outs. The erosive mechanism by products of periods of ‘natural’ landscape stability which artefacts and other archaeological matter – they are evidence of the deliberate creation of had accumulated in blow-out hollows was more stasis by the spreading of pedogenic materials. In clearly documented than has been the case previ- this case, therefore, we are dealing with a relative ously in this or any similar landscape (ibid, 1). scale of past human agency – decisions to persist Buried palaeosols associated with archaeological with soil stabilisation or to abandon the process, are material were interlaminated with layers of wind- conditioned by locally specific factors and affected by blown sand; pollen analysis from dune slack area varying rates of continuing erosion and wind-driven (the results of which extended back only c 3,000 inundation by sand (the ‘Bad Year Syndrome’ affects radiocarbon years) confirmed that changes in these landscapes as much as any other, if not more vegetation had been very marked, showing alter- so). Identifying the tipping-points of agricultural nating predominance of woodland and heath since and settlement feasibility, and winning or losing the Bronze Age. The consequent interpretation was the struggle against the sand, is a critical aspect that settlement had taken place in the Neolithic of our search for explanations for the interrupted and the Bronze Age, and subsequently in the Early character of human settlement in these areas. It is to High Medieval periods, on stabilised agricultural therefore critical that we have an informed grasp soils which were separated by intervals of gradual, both of the general geomorphological background but ultimately extensive, aeolian sand inundation and also its local specifics – so building a true beginning in the mid to later second millennium multi-disciplinary landscape perspective is critical BC, and succeeded by another more sudden and here. In dune systems, past land surfaces bearing catastrophic episode in the Later to Post-Medieval archaeological and palaeoenvironmental informa- period, coinciding with the well-known effects of tion of great importance are interlaminated with climatic downturn at that stage. aeolian deposits which have very different accu- A further example of the growing ‘landscape mulation and erosional characteristics in terms of approach’, albeit still conditioned largely by visible both materials and durability. Subsequent geomor- exposure rather than prospection-based methods, is phological changes have severely compromised the the campaign of research mounted by Durham Uni- integrity of these deposits, but quantifying this is an versity at Freswick Links, Caithness, between 1979

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