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The Matrix: Connecting Time and Space in Archaeological Stratigraphic Records and Archives

Keith May

Cite this as: May, K. 2020 The Matrix: Connecting Time and Space in Archaeological Stratigraphic Records and Archives, Internet Archaeology 55.


The records of archaeological stratigraphic data and the relationships between stratigraphic units are fundamental to understanding the overall cohesiveness of the archaeological archive of an excavation. The information about individual units of excavation identified on sites with complex stratigraphy is most often held in the site database records and stratigraphic matrix diagrams, usually documenting relationships based on the laws of stratigraphic superposition and the Harris matrix conventions (Harris 1979). However, once the matrix diagram has been used to record the information during excavation, there is far less consistency in how those stratigraphic records, and any associated phasing information, are finally deposited in the archives. For that valuable data to be successfully identified and re-used (particularly if the rest of the data is in a database), the stratigraphic and phasing data needs to be in a format that can be interrogated as part of the database. In practice, often only a (paper) copy of the matrix diagrams make the archive. This means that the critical temporal and spatio-temporal relationships upon which the phasing of sites is built, cannot usually be interrogated or (re)used without lengthy and wasteful re-keying of that data into another version of the database.

Composite image showing computer screens and a person sitting down drawing on permatrace in a desert-like environment
Examples of keeping a ‘running matrix’ drawing on permatrace and stratigraphic data in a handheld database during fieldwork, and the use and analysis of matrix data during post-excavation

The stratigraphic, sequencing and temporal information held in a matrix is fundamental in further studies of the site records and in working out how the site may relate to other excavated sites of similar or related dates and phases. This article will suggest ways in which the stratigraphic data from excavations and the reasoning processes carried out in subsequent analysis could be better managed, to make matrices (re)useable as part of a more integrated digital archive.

This article examines how conceptual reference modelling, particularly using temporal relationships, can be used to explore these issues and how associated technologies could enable semantically-enriched deductions about the spatio-temporal and purely temporal relationships that fundamentally link archaeological data together. It will also consider where further work is needed both to deal with analysis of spatial or temporal records and to enhance Bayesian chronological modelling and associated temporal reasoning, and how this may form the basis for new linkages between archaeological information across space-time.

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  • Keywords: stratigraphy, matrix, temporal reasoning, phasing, Bayesian chronology, data standards, digital archive
  • Accepted: 28 July 2020. Published: 29 Sept 2020
  • Funding: The publication costs of this article were paid by Historic England IRO publication funding.
  • PDF download (main article text only)

Corresponding author: Keith MayORCID logo
Historic England

Full text

Figure 1a/Figure 1b: Section drawing with example of a Harris matrix from Historic England recording manual (2006)

Figure 2: Drawing by Mortimer Wheeler of a section across the cellar in Sacellum at Segontium, with added colours highlighting different 4D floor phases in contrast to Harris Matrix diagram boxes (in contrast to Harris Matrix boxes in Figure 1b)

Figure 3: Example matrix annotated to show how Roskams' 'sub-periods' represent the overlaps in time relationship and Roskams 'periods' represent occurs during and meets in time relationships. (After Roskams 2001, fig. 31)

Figure 4: Table of Allen temporal operators showing pairings of temporal relationships

Figure 5: Silbury Hill - stratigraphic matrix archive with annotations to highlight implicit Allen relationships. Silbury Matrix, The site Harris matrix in English Heritage 2014. (Including Video with audio explainer [transcript])

Figure 6a/Figure 6b: Landscape Research Centre matrix diagram and spreadsheet

Figure 7: Harris 1989, figure 25. In this illustration, a section has been split into 24 periods. The odd numbers are depositional periods and the even numbers are interfacial periods. Depositional periods are represented best by section drawings; the interfacial periods by plans (Harris 1979)

Figure 8: Allen temporal operators – see also Figure 5 for use in matrix diagram

Figure 9: Allen operators as CIDOC-CRM properties with allocated 'P' numbers

Figure 10:Diagram showing temporal relations in the continuity of hypothetical pit fills (based on an original version by Paul Cripps)

Figure 11: 'The Rope of time' (After Harris 1979, fig. 2)

Figure 12: Schematic representation of three possible relationships between older and younger chronological phases: left, chronological phases 1 and 2 separated, b1 > a2; middle, chronological phases 1 and 2 abutting, b1 meets a2; right, chronological phases 1 and 2 overlapping, b1 < a2. (After Dye and Buck 2015, fig.7, and adapted from Buck et al. 1996, fig. 9.8).

Allen, J.F. 1983 'Maintaining knowledge about temporal intervals', Communications of the ACM 26(11), November 1983. 832–43.

Barceló, J. and Bogdanovic, I. (eds) 2015 Mathematics in Archaeology, Boca Raton: Taylor and Francis.

Bronk Ramsey, C. 2015 'Bayesian Approaches to the Building of Archaeological Chronologies' in J. Barceló and I. Bogdanovic (eds) Mathematics in Archaeology, Boca Raton: Taylor and Francis. 272-292.

Buck, C.E., Cavanagh, W.G. and Litton, C.D. 1996 Bayesian Approach to Interpreting Archaeological Data, Chichester: Wiley and Sons Ltd.

Carver, M. 2009 Archaeological Investigation, Abingdon: Routledge.

Clark, P. 2000a 'Negative features and interfaces' in S. Roskams (ed) Interpreting Stratigraphy, British Archaeological Reports Int. Ser. 910, Oxford: Archaeopress. 103-5.

Clark, P. 2000b 'Post-excavation analysis: moving from the context to the phase' in S. Roskams (ed) Interpreting Stratigraphy, British Archaeological Reports Int. Ser. 910, Oxford: Archaeopress. 157-59.

Cripps, P., Greenhalgh, A., Fellows, D., May, K. and Robinson, D-E. 2004 'Ontological modelling of the work of the Centre for Archaeology', CIDOC CRM Technical Paper. [PDF] and The CRM-EH Diagram, [PDF]

Doerr, M., Stiff, Nm, Crofts, N., Stead, S. and Gill. T. 2011 CIDOC CRM,

Doerr, M., Felicetti, A., Hermon, S., Hiebel, G., Kritsotaki, A., Masur, A., May, K., Ronzino, P., Schmidle, W., Theodoridou, M., Tsiafaki, D., Christaki, E. 2018 CRMarchaeo Excavation Model v1.4.4.

Dye, T.S. and Buck, C.E. 2015 'Archaeological sequence diagrams and Bayesian chronological models', Journal of Archaeological Science 63, 84-93.

English Heritage 2014 Silbury Hill archive [data-set], York: Archaeology Data Service [distributor]

Force 11 2016 FAIR Data Principles [Last accessed: 28 May 2020]

Harris, E. 1979 'The laws of archaeological stratigraphy', World Archaeology 11(1), 111-17.

Harris, E. 1989 Principles of Archaeological Stratigraphy, 2nd Edition, London and New York: Academic Press.

Harris, E., Brown, M. and Brown, G. (eds) 1993 Practices of Archaeological Stratigraphy, London: Academic Press Ltd.

Historic England (was English Heritage)2006 Recording Manual, Internal publication.

Ioppolo, G. and Sartorio, G.P. 1990 Lo Scavo Archaeologico, Commune di Roma, Assessorato alla Cultura.

Lucas, G. 2005 The Archaeology of Time, London: Routledge.

Niccolucci, F. and Herman, S. 2015 'The formal logical foundations of archaeological ontologies' in J.A. Barceló and I. Bogdanovic (eds) Mathematics in Archaeology, Boca Raton: Taylor and Francis. 257-271.

Powlesland, D. and May, K. 2010 'DigIT: Archaeological summary report and experiments in digital recording in the field', Internet Archaeology 27.

Roskams, S. (ed) 2000 Interpreting Stratigraphy. Papers presented to the Interpreting Stratigraphy Conferences 1993-1997, British Archaeological Reports Int. Ser. 910, Oxford: Archaeopress.

Roskams, S. 2001 Excavation, Cambridge: Cambridge University Press.

Shepherd, L. 1993 'Interpreting landscapes - analysis of excavations in and around the southern bailey of Norwich Castle' in J. Barber (ed) Interpreting Stratigraphy, Edinburgh: AOC (Scotland) Ltd. 3-10.

Spence, C. (ed) 1990 Archaeological Site Manual, 2nd Edition, London: The Museum of London.

Taylor, J.S. 2016 Making Time For Space At Çatalhöyük: GIS as a tool for exploring intra-site spatiotemporality within complex stratigraphic sequences, Unpublished PhD thesis, University of York.

Tudhope, D., May, K., Binding, C. and Vlachidis, A. 2011 'Connecting archaeological data and grey literature via semantic cross search', Internet Archaeology 30.

Vandevelde, S., Brochier, J.É. , Desachy, B., Petit, C., and Slimak, L. 2018 'Sooted concretions: A new micro-chronological tool for high temporal resolution archaeology', Quaternary International 474, Part B, 103-118.

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