Archaeological deposit modelling comprises a wide variety of approaches to addressing the interrelated challenges of interpreting archaeological sites and landscapes, efficiently targeting fieldwork and managing the archaeological and palaeoenvironmental resources. By interpolating between data points, models provide visualisations and quantifications of layers and deposits, in either 2D or 3D. The sources of data can be broad, linking archives with new fieldwork, and combining boreholes and geotechnical data with the results from geophysics and excavation. By integrating artefact distributions, deposit models can assist in archaeological interpretation, and can identify patterns and gaps in past cultural activity. Furthermore, they provide a means for mitigation and landscape management, such as through identifying or predicting areas of greater archaeological or palaeoenvironmental sensitivity. With the widespread accessibility of digital tools, the potential value provided by deposit modelling is within reach, if only there were sufficient published examples of how this might be achieved.
Deposit modelling and archaeology subsequently presents 15 case studies, each focusing on different questions and challenges, and working at a variety of different spatial and temporal scales. Edited by a cross-sector research team and with contributions from both creators and end-users of deposit models, the volume provides a fresh new attempt to engage with the challenges of definition and best practice by presenting these case studies. It does this in an honest and reflexive manner, highlighting lessons learned throughout the process. Funded by Historic England, the volume represents a principal outcome from a project that commenced with a workshop held in London in 2016. It is supplemented by a paper published in Geoarchaeology and will feed into new Historic England ‘best practice guidelines’. For a field that has emerged organically, this is clearly of value, addressing re-using archive data, the limits to extrapolation between data points, issues of resolution and how to ensure that the resulting models are widely understood.
The book begins with an Introduction by the editors that includes a helpful summary of what deposit modelling in archaeology is and how it fits into the broader archaeological process. This chapter also considers the challenges of archiving and disseminating the results, highlighting the need for clear protocols. The subsequent chapter by Martin Bates contextualises the subject further, outlining the deeper ancestry of the approach in relation to the geosciences. He raises caution in relation to the need to assess critically the input data, and to make sure that the resulting models are understandable.
The bulk of the book centres on 15 case studies from England spread geographically from the south coast to York; a city that has benefited from many decades of deposit modelling approaches, as noted in the chapter by Kurt Hunter-Mann and John Oxley. The majority of chapters present results from projects in London or the south and south-east of England, but, in addition to York, other examples are drawn from Leicestershire, Nottinghamshire and Cheshire. The concluding chapter by Chris Carey et al. draws attention to this imbalanced geographic distribution, recognising that “the application of deposit modelling is extremely variable across the country, with the majority of studies undertaken in south-east England”. They suggest that this reflects both the clustering of experienced practitioners as well as the result of a regional focus of intense economic development in recent years. The authors note however, that current and emerging infrastructure projects, particularly those across the Midlands and northern England, provide the opportunity for new extensive deposit modelling projects. In this respect, this book is extremely timely.
The case studies are organised into seven groups. These comprise modelling early human occupation, areas of linear development such as road schemes, and dryland/wetland interfaces, incorporating data from multiple sites across a landscape, using deposit modelling in post-excavation analysis, sustainable resource management and the use of deposit models in curatorial decision-making. Strong themes that emerge throughout the case studies include the value of integrating multiple datasets deriving from different sources. Within this context, the chapter by Chris Carey and David Knight highlights the benefits of applying a staged approach to the integration of different datasets in the development of deposit models. The reflections presented within some of the case studies emphasise how the use of the deposit model changed throughout the lifetime of the project. The need for chronological control within deposit models is clearly important, and this is discussed in most of the case studies. For the majority, control was achieved through the use of radiocarbon dates, or via the integration of stratigraphic data with artefact distributions. In two instances, data for chronological control were provided through OSL (in the chapter by Keith Wilkinson et al.) and dendrochronology (in the chapter by Martin Brook and Dan McConnell).
It is interesting to see different approaches used throughout the book, such as the different interpolation techniques that include inverse distance weighting (e.g. the chapters by Dan Young et al., Mary Nicholls et al.), tension spline (e.g. Kristina Krawiec) and kriging, in which interpolated values are modelled by a Gaussian process (e.g. Keith Wilkinson et al.). For all of the considerable variety of approaches presented in the collection of case studies, some readers would find it useful to have more detail regarding factors such as these, including the impact that different interpolators would have on results. That said, the chapter by Andy Howard et al. raises the issue of interpolation in relation to the value of regularly spaced input data, and provides references for exploring this further.
The case studies presented in this book provide an excellent grounding for anyone either intending to use deposit models, or considering creating them. The different approaches offer a wealth of ideas for application within other landscapes and, because the case studies are presented in an open and considered way that highlights both benefits and challenges, this book will be of value to those already working with archaeological deposit models. Identifying the similarities and differences between the various case studies is made more straightforward by the strong editorial lead that maintains consistency throughout, including summary tables of data used and flow diagrams of the approaches taken. In this way, the editors invite the reader to draw their own conclusions.
Deposit modelling and archaeology highlights challenges ranging from the lack of standardisation of approaches to skills gaps across the sector. Beyond feeding into the creation of new standards and best practice, the case studies provide ideas and inspiration. It is refreshing to see how different researchers have used different forms of data and software types for creating models aimed at addressing different challenges and questions.
As Timothy Darvill states in the Foreword to the volume, “deposit modelling opens doors into new areas of archaeological endeavour”.
