At the beginning of March the UK chapter of CAA (Computer Applications and Quantitative Methods in Archaeology) held their annual conference in Leicester. It was a two day event and there were lots of great talks of which I filmed a couple:
Seeing things differently. The use of combined geochemical and geophysical prospection techniques to investigate early Islamic town planning.
Welham, K (Bournemouth University), Pitman, D (Bournemouth University), Duckworth, C (University of Leicester), Govantes-Edwards, D (Universidad Nacional a Distancia), Barbier, Y (Bournemouth University) and Córdoba de la Llave, R (Universidad de Córdoba)
This paper examines the combination of in-situ portable X-Ray Fluorescence (pXRF – Niton XL3TGOLDD+), and geophysical survey data obtained from the 10th century, early Islamic site of Madinat al-Zahra in Cordoba, Spain. The work presented here forms part of a larger research project that investigates the key role that glass, ceramic, and metal production had in the creation of urban centres, and the important question of technology transfer between Muslim, Christian and Jewish groups within Spain and in the wider Mediterranean at this time.
Preliminary results are presented that demonstrate how this novel approach to site-wide prospection has identified a range of likely production areas within the medina (city) at Madinat al- Zahra. Elemental ‘hotspots’ obtained from a relatively coarse pXRF survey of the top-soil at the site are seen to be directly linked to substantive magnetic anomalies that have geophysical signatures suggestive of high-temperature activities. Iron working and probable ceramic production were located, and specifically areas of elevated lead, copper and manganese were found to be linked to the remains of furnaces that may have produced the famous glazed ceramics known to be manufactured on the site. The results move beyond enabling a more nuanced approach to the interpretation of geophysical datasets, and towards an integrated archaeological prospection tool on a site-wide level.
The potential futures of drone recording in Archaeology and Cultural Heritage
Daniel Joyce (University of Southampton)
Drones have already made their mark in archaeology and cultural heritage recording by providing an aerial platform for taking photographs from altitude, at their simplest allowing photographs to be taken from places that would otherwise be difficult, if not impossible.
But the use of drones can open up whole new innovative recording techniques, a number of which I will be discussing. These will include the automated photogrammetric mapping of sites using a drone autopilot to provide detailed 3D models or Digital Elevation Models for GIS applications, the mapping of sites using near-infrared imaging to aid in identifying buried archaeological remains. The same technology can also provide a means to accurately record building facades with the help of open source software. All of this data can easily be processed using the potential of cloud computing.
While recently developed flight control technology together with computer vision technologies provide an innovative way to record site tours by having the drone follow the person giving the tour using cinematic style controls.
Future developments in drone technologies open up the possibility of fleets of drones autonomously navigating and recording sites on their own using different sensor packages.
With decreasing costs, increased automation and ease of use, drones may become a common tool on almost all archaeological sites autonomously recording the progress of the excavation at set intervals and providing a level of recording detail not seen before without the need of human intervention.
Quantitative Route Analysis and the Construction of Route Models
Michelle de Grouchy (Durham University & University of Tübingen)
It is now possible to quantitatively assess route models against preserved route ways in the archaeological record (de Gruchy 2015), opening up the possibility for testing the potential importance of individual variables in past travel. The assessment, however, is only as good as the model. A route model is built by incorporating different variables (slope, land cover, etc.) into one of many functions designed to assess cost of movement. This paper critically examines common functions used in GIS to generate these models, the assumptions they make, their strengths and weaknesses, and how archaeology might modify and develop functions to more accurately reflect the diversity of human travel across the landscape.
de Gruchy, M.W. (2015) “Beyond Replication: The Quantification of Route Models in the North Jazira, Iraq” Journal of Archaeological Method and Theory. Available online: http://link.springer.com/article/10.1007/s10816-015-9247-x
Missing Data and GIS: A Case Study Using Romano-British Metalwork Hoards
Rachael Sycamore (University of Leicester)
The requirement to integrate modern data with older records, sometimes centuries earlier, is increasing within archaeological applications of GIS. This problem can result in huge discrepancies in the information available within geodatabases alongside numerous, often differing levels of accuracy appearing in the spatial location of archaeological remains. However, there has been relatively little critique of how we analyse this data together and methods of dealing with the variations in data quality. There is little use critiquing complex analytical techniques and developing ‘Big Data’ projects if we do not understand the weaknesses of the data we are using.
This paper will discuss the theoretical concerns of integrating records from Britain of Roman hoards containing metal objects to use in GIS and reveal how the issues raised by this case study apply generally to archaeological applications of GIS. Roman hoards have been discovered since the 1600s and many have been lost. There are also differing levels of detail in the records and various levels of spatial accuracy surviving regarding their location. These considerations apply to the majority of archaeological remains and as a result they must be critically understood.
The way that I field: analysing field system morphology using GIS.
Chris Green (University of Oxford)
From at least the Middle Bronze Age to the Romano-British period (and sometimes beyond), field systems were a widespread feature of the English landscape. Today, many of these ancient boundaries and divisions are still visible from the air, whether as earthworks, stone banks or cropmarks. Since the 1980s, Historic England’s ongoing National Mapping Programme (NMP) has plotted the layout of these features based upon aerial photographs. This paper will discuss taking the mapped results of the NMP for Bronze Age to Romano-British field systems and re-plotting them so that morphological variables are able to be measured. Specifically, methodologies have been developed for analysing the following field system characteristics: orientation, extent, bank / ditch length and count, junctions / nodes, and associated dating evidence. These variables for a set of 40 field systems, totalling almost 6,000 hectares in extent, have been gathered and compared against each other and against various local terrain characteristics, across time, space and type. The paper will discuss the methodologies developed and the patterns (and sometimes lack of patterns) discovered following analysis of the results.
Expense vs. Effect :An analysis of selected variables that affect the production of cost surfaces.
Edward Caswell (Durham University)
Cost Surfaces Analysis has become a common, if sometimes controversial, tool within archaeological study. Today, there are numerous GIS packages that allow the creation of cost surfaces and least cost paths at the “push of a button” (ArcGIS, GRASS, Idrisi). However, this is often at the cost of hiding the technicalities of the program’s method, which may not always be ideal for archaeological research. As such it is often advised that these pre-prepared systems should not be overly relied on (Herzog, 2013, 184, Rademaker et al. 2012, 38). Yet, there are few papers dedicated to assessing the effects of varying any of the modifiable parameters available to each program, and therefore few guides in selecting an appropriate methodology. Those that that do focus only on a limited selection of variables (Gietl et al 2008, Magyari-Sáska, et al 2012, Herzog 2014).
This paper builds on those existing works by systematically exploring the differences in cost surfaces produced when varying:
- GIS package (ArcGIS and GRASS).
- DEM resolution.
- Cost components (slope and terrain).
- The coefficients that determine the cost of human movement.
It will demonstrate the variability in catchment area size and least cost paths that are produced through changing these variables across ten case study zones. The results will identify which variables have the most significant effect on creation of cost surfaces and least cost paths in order to demonstrate which should be made explicit within publications and which have little overall effect to archaeological interpretation.
Herzog, I. 2013. ‘The potential and limits of optimal path analysis’, in Bevan and Lake (eds) Computational Approaches to Archaeological Spaces Vol. 60. Left Coast Press
Herzog, I. 2014. ‘Least-cost Paths – Some Methodological Issues’, in Internet Archaeology 36, http://dx.doi.org/10.11141/ia.36.57
Gietl, R., Doneus, M., & Fera, M. 2007. ‘Cost distance analysis in an alpine environment: comparison of different cost surface modules’, in Axel Posluschny, Karsten Lambers and Irmela Herzog (eds) Layers of Perception. Proceedings of the 35th International Conference on Computer Applications and Quantitative Methods in Archaeology (CAA) Berlin, Germany, April 2-6, 2007. 316–21.
Magyari-Sáska, Z. & Dombay, Ş. 2012. ‘Determining minimum hiking time using DEM’, in Geographica Napocensis Anul 82, pp.124-129.
Rademaker, K., Reid, D. A., & Bromley, G. R. (2012). Connecting the Dots: least cost analysis, Paleogeography, and the search for Paleoindian sites in southern highland Peru. In White and Surface-Evans (eds) Least Cost Analysis of Social Landscapes: Archaeological Case Studies. University of Utah Press, Salt Lake City. 32-45
Walking Across Beach Sand is Hard and Other Discoveries: first results of assessing the time cost of moving through various terrains
Michelle de Grouchy (Durham University & University of Tübingen), Edward Caswell (Durham University) and James Edwards (Durham University)
The majority of archaeological studies using cost surface analysis rely on one component of terrain, slope, to reconstruct the cost of human travel (Herzog 2014). Preference for this component has led to numerous papers assessing how an energetic (e.g. Rose et al 1994, Pandolf et al 1977, Minetti et al, 1993) and time (Tobler 1993, Langmuir 1995, Arroyo, 2006) cost might be calculated, using scientifically observed data of human movement. Dedication to slope based models may be justified by our certainty of the height of terrain in the past. However, the plethora of environmental samples now available to archaeologists also allows a similarly certain reconstruction of terrain types (e.g. High Grass, Forest, Sand). Yet comparatively little research has been carried out assessing the energy costs of moving through different terrain types (Giovani and Goldman 1971, Soule and Goldman 1972) and these singularly evaluate the relative difficulty of moving through varying terrains using metabolic cost. No data has been published on the time taken to cross these differing terrain types. This paper seeks to redress this imbalance by presenting wholly new data identifying the friction co- efficient for 6 terrain types found in Britain. Critically these results measure the cost of human travel in terms of time, the first study to do so. The paper will then demonstrate that, while terrains do have a clear effect on travel, the coefficients produced from studying metabolic rate should not be combined with those that assess the time taken to walk these same routes.
Arroyo, A. B. M. 2009. ‘The use of optimal foraging theory to estimate Late Glacial site catchment areas from a central place: The case of eastern Cantabria, Spain’, in Journal of Anthropological Archaeology 28, pp.27-36.
Giovani, B. and Goldman, R.F. 1971. ‘Predicting metabolic energy cost’, in Journal of Applied Physiology 30, pp.429-433.
Herzog, I. 2014. ‘Least-cost Paths – Some Methodological Issues’, in Internet Archaeology 36, Section 5 http://intarch.ac.uk/journal/issue36/5/5.html.
Langmuir, E. 1995. Mountaincraft and Leadership, Sports Scotland, Edinburgh.
Minetti, A. E., Ardigo, L. P. & Saibene, F. 1993. ‘Mechanical determinants of gradient walking energetics in man’, in The Journal of Physiology 472, pp.725-735.
Pandolf, K. B., Burse, R. L. & Goldman, R. F. 1977. ‘Role of physical fitness in heat acclimatisation, decay and reinduction’, in Ergonomics 20, pp.399-408.
Rose, J., Ralston, H. & Gamble, J. 1994. ‘Energetics of Walking’, in J. Rose & J. Gamble (ed.), Human Walking, Williams and Wilkins, Baltimore, pp.45-72.
Soule, R.G. and Goldmand, R.F. 1972. ‘Terrain coefficients for energy cost prediction’ in, Journal of Applied Physiology 32, pp.706-708.
Tobler, W. 1993 Non-isotropic Geographic Modeling, Technical Report 93-1. http://www.geodyssey.com/papers/tobler93.html.
The Embodied GIS. Using Mixed Reality to explore multi-sensory archaeological landscapes.
Stuart Eve (L- P Archaeology)
We are at a turning point in development and thought about multi-sensorial engagement using digital mediation. From Oculus Rift VR googles, Google Cardboard, noise-reducing headphones, vibrating-haptic simulating gloves, smell generators and virtual treadmills, every week a new technology or software emerges that can be used to virtualise, augment or diminish our reality, across all of our senses. Digital archaeologists have always been at the fore-front of using these new technologies and one glance at past proceedings of the CAA conferences show how enthusiastic and competent archaeologists are at deploying them in heritage applications. Addressing the themes of the conference, and looking towards the future of GIS, this paper explores a number of ways that these new multi-sensory developments can be harnessed and linked to a traditional GIS database using Mixed Reality. I will demonstrate the implementation of an embodied GIS – allowing a multi- sensorial experience of archaeological data, in-situ, and enabling archaeologists to explore data in new ways, encouraging new interpretations by thinking and working through the body.
People make practice: How networks and Metapopulations can help us understand the Lower to Middle Palaeolithic Transition
Peter Alfano (University of Leicester)
Traditional interpretations of the Lower to Middle Palaeolithic transition present a broad sweeping change from traditional core and flake industries, often with a bifacial element, normally typified by the Acheulean, to a wholesale adoption of prepared core technologies such as Levallois. Examination of the archaeological record in a single region, for example Central Europe, and with any detail, shows this characterisation to be one that fails to highlight the variety of, and subsequent changes, in technological practice present during the period from 400 to 200 thousand years ago (kya).
By adopting a theoretical approach inspired by metapopulation ecology, I hope to explore how factors such as, population density, and changes in environmental affordance, may have affected the transfer of information and practice across social networks during the Lower to Middle Palaeolithic. It should be possible to create an Agent Based Model (ABM) to explore the nature of cultural transmission and the maintenance of practice during the period in question.
It is hoped that this will provide further evidence for reimagining the Lower to Middle Palaeolithic transition as a nuanced, localised, event which happened in in different places at different scales.
Contrasting the influence of factors shaping the spread of early farming using an adapted cultural dissemination model
Nelis Drost and Marc Vander Linden (University College London)
Computational models have long been used to answer questions about spreading phenomenon in archaeology, but until recently the models used have primarily been reaction-diffusion systems, derived from or inspired by Fisher’s (1937) ‘wave of advance’ model. These models have the benefit of being analytically manageable, and have been used to provide various quantitative measures of such spreads, such as the speed of advance, or the localised direction of a wave.
More recently, agent based models have found use in exploring the more qualitative aspects of spreading scenarios, and these are better suited to testing hypotheses about how, or why, a phenomenon spread.
We present one such model, derived from Axelrod’s (1997) cultural dissemination model, and its application to the study of the spread of early farming into South-Eastern Europe. A series of modifications to the model allows us to better represent both the spatial reality of archaeological data, and the specific scenario of neolithisation. Further variation allows us to contrast conflicting hypotheses about how farming spread, and what level of interaction took place within and between both the already present mesolithic cultures, and the expanding neolithic.
By contrasting the behaviour of these models with a newly collated data set of dates and material assemblages, utilising approximate Bayesian computation, we hope to discover to what degree various factors shaped the spread of the neolithic, and the transient cultural landscape of the time.
Agent Based Modelling in Archaeology- When Will It Get Complex?
Doug Rocks-Macqueen (Landward Research Ltd.)
Archaeologists were one of the first groups to embrace agent based modelling (ABM). For several decades now we have been modelling the past with ABM. In that time our models have become much bigger – more agents, larger study areas, more detailed data, 100x more computing power, etc. But, our models are not any more complex than they were decades ago, with some exceptions. Archaeology AB models tend to focus on modelling one or two variables for very specific times and spaces. Enough agents interacting can create the semblance of complex outcomes but they do not learn in the process and as such most ABM do no model complex systems. This paper examines the challenges to creating agents in ABM that learn and base their interactions upon past interactions. It will offer some solutions to these challenges and the potential implications of this work for archaeology and modelling the past.
Community memories and virtual reality: the 3D reconstruction of St. Mary Bishophill Senior
Angleo Maria Cappa (University of York)
This presentation discusses the results of a research study focused on the relationship between virtual heritage and local communities. It examines how virtual heritage can be used to analyse community memories through the realisation of a 3D model of the church of St. Mary Bishophill Senior, which used to be York.
Furthermore, this research adopted a direct interaction with the local community of York in order to understand whether or not their memories can be physically represented in a virtual environment, as well as to analyse the overall relationship between the community itself and computer-based reconstructions.
The results, collected at the end of the project, showed that despite the complexity of representing intangible heritage, however 3D modelling and computer graphics representations have proved to be excellent tools to bring back memories to people’s minds. Hence to examine the high level of association between virtual reality, its level of engagement with the audience, and the historic significance of an area.
The Matrix Reloaded: Explorations in Directed Acyclic Graphs
John Layt (L-P Archaeology)
The Harris Matrix has long been established as a core tool in archaeological stratigraphy and the single context recording system. Little has advanced on the computing side however since the release of BASP Harris, a closed source DOS program, over 25 years ago. While the matrix is used in daily archaeological practice, few people use specialist digital tools for this purpose, choosing instead to manually draw matrices using pen-and-permatrace, generic drawing packages, or even spreadsheets. Even once drawn, the matrix is often not used to it’s full potential in navigating or exploring the archaeological dataset, it remains a static object with no interaction with the underlying data or overlying presentation layer. Much of this is due to a number of inherent failings in the existing Harris Matrix software and their closed development models, but also in the state of graph drawing algorithms. This paper will examine the current state of Harris Matrix software, why they fail to meet the practical requirements of archaeologists and archivists, and present some interim results of ongoing research into developing new software tools, file formats, and drawing algorithms.
Interactive navigation and visualization of digitized archaeological excavations
Radu Comes (Technical University of Cluj-Napoca), Zsolt Buna (Technical University of Cluj-Napoca) and Liliana Mateescu–Suciu (Babeș-Bolyai University)
Within the past decade, a wide variety of digitizing solutions that can generate accurate 3D models have seen a widespread in popularity and adoption by archaeologist and researchers around the world. Currently 3D digitization using laser scanners or photogrammetry solutions represents a viable process that can acquire digital datasets of archaeological excavations. For a more precise digital representation of an archaeological excavation each artefact should be processed individually. Using the resulted 3D models the archaeological excavation can be assembled inside a virtual environment offering the possibility to explore the excavation layout and have all the artefacts represented by their 3D digital replica.
This paper presents virtual environments that allow the users to explore the archaeological excavation using natural gestures. The virtual environment uses motion sensors (Kinect and LeapMotion) in order to track the natural gestures of the users in real time enabling an interactive navigation. Some of the issues regarding large datasets integration in virtual reality environments will be presented as well as the advantages of natural gestures navigation and interaction with archaeological datasets.
Competing against the status quo: Are we building digital orphans?
Hugh Corley (Historic England)
There are various digital excavation recording systems currently being used both in the UK. This paper will argue that instead of competing against each other, these digital systems are competing against resistance to adoption. To address this, there needs to be a conversation and evaluation by the users and developers of these systems to discuss their strengths, weaknesses and future developments. To do this successfully, we also need to make sure we understand all of the different motivations and priorities involved throughout the life cycle of projects.
We need to compare how these systems work and how they contribute to the management of the production of data. Putting the technical challenges to one side, this paper will explore issues around user needs, expectations and assumptions. Increasing our understanding needs to come from not only learning from what works but also what has failed and whether this failure is the result of the technology, its implementation or other factors. As we move forward with the use and development of these systems we need to ensure we have the clearest picture of what processes will benefit from digital and those that do not. The aims are to improve our understanding of how this data will be used, what more can we aim to do to ensure efficient and accurate records are created and focus development on those areas that will benefit from being born digital.
The Endangered Archaeology Image Interpretation Methodology
Louise Rayne (University of Leicester)
This paper presents a discussion of the image interpretation, remote-sensing and GIS based methodology employed by the Endangered Archaeology in the Middle East and North Africa project (EAMENA) at the Universities of Leicester and Oxford. EAMENA is creating a database containing information about archaeological sites of all types and periods and identifying those under threat of damage and destruction.
This paper discusses some of the problems with relying on remote interpretation of archaeology. We are entering data about archaeology into our database based on a visual examination of Google Earth images. This offers a relatively constrained view of the landscape in that the original image data is not available. In some cases there are few or no high quality images of specific areas. Moreover, it can be difficult to make interpretations of features without further validation from fieldwork. However, for specific regions we have been utilising a greater range of data to record information about archaeological sites. These include high resolution imagery such as WorldView and historical aerial photographs and 1960s-70s declassified spy satellite images.
Image interpretation of archaeology often can be the best available method for recording it relatively quickly and cheaply, including in areas where major and irreversible damage is occurring and where fieldwork is not possible. Even where sophisticated interpretations cannot be made, the presence of archaeology can be listed. The open-access database will be made available online and will assist all those with responsibilities for the management, protection and promotion of their cultural heritage. Our data have already been used for these purposes in Libya and Morocco.
Digital frameworks in archaeological fieldwork: practices for archiving, management and visualisation of Structure-from-Motion data.
Fabrizio Galeazzi (Archaeology Data Service) and Peter Jensen (Aarhus University)
In the last decade, Structure-from-Motion technique has demonstrated to be a powerful tool for the documentation, analysis and interpretation of the archaeological record. As a consequence, its use has greatly accelerated, becoming more commonly applied to archaeological practice.
To date, there have only been a few attempts to create prototype management systems for the archiving, visualization and analysis of 3D representations of archaeological excavations. The first part of this paper defines new approaches for the long-term preservation of Structure-from-Motion data, metadata and paradata in the ADS (Archaeology Data Service) cyber-infrastructure. This is part of a major effort to develop standards for the preservation and visualisation of 3D data in ADS.
The second part of the paper shows how Structure-from-Motion data can be integrated in online data management systems, which favour the preservation, visualisation and analysis of the archaeological record. Two different systems are presented and compared: (1) the first one, ADS 3D Viewer, is a web-based dynamic visualization system developed to access 3D data archived in the ADS infrastructure; (2) the second is a cross platform application linked to an online spatial database. Starting from the comparison and evaluation of existing infrastructures, the aim of this contribution is to develop common frameworks for the management of Structure-from-Motion data and open a discussion among archaeological practitioners. This research will be a useful instrument for the development of future infrastructures, which address the different needs, and expectations of the user.