USING COMPUTERS IN ARCHAEOLOGY As computing becomes increasingly essential to the work of the archaeologist, archeologists require a clear understanding of the impact of information technology upon their discipline. This non-technical introductory volume discusses and explains the influence of computers on all aspects of archaeological research and interpretation, from survey, excavation and landscape to museums, education and communicating the past. The author meets the need of the archaeologist to keep abreast of how computers can assist at all stages of archaeological research and data analysis. Theoretical information, focusing on Geographical Information Systems, for example, is presented through description of archaeological processes, and is consistently practical and free from jargon. The author acknowledges the problem of obsolescence in computing and presents archaeological technology as an on-going, constantly changing process rather than as a final, achievable state. The book will thus remain relevant through future advances in technology and informative about the general principles of, and the issues arising from, the relationship between computers and archaeology. Highly illustrated and referenced throughout with case-studies and examples, Using Computers in Archaeology: Towards Virtual Pasts is a timely survey of this increasingly important area of archaeology, catering for both the student and the experienced archaeologist. Gary Lock is Lecturer in Archaeology at the University of Oxford, editor of Beyond the Map: Archaeology and Spatial Technologies (2000) and co-editor of On the Theory and Practice of Archaeological Computing (2000). USING COMPUTERS IN ARCHAEOLOGY Towards virtual pasts Gary Lock First published 2003 by Routledge 11 New Fetter Lane, London EC4P 4EE Simultaneously published in the USA and Canada by Routledge 29 West 35th Street, New York, NY 10001 Routledge is an imprint of the Taylor & Francis Group This edition published in the Taylor & Francis e-Library, 2003. © 2003 Gary Lock All rights reserved. No part of this book may be reprinted or reproduced or utilized in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers. British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library Library of Congress Cataloging in Publication Data Lock, G. R. (Gary R.) Using computers in archaeology: towards virtual pasts / Gary Lock. p.cm. 1. Archaeology–Data processing. 2. Archaeology–Information technology. 3. Geographic information systems. I. Title. CC80.4.L63 2003 930.1´028–dc21 2002035669 ISBN 0-203-45107-4 Master e-book ISBN ISBN 0-203-45698-X (Adobe eReader Format) ISBN 0–415–16620–9 (hbk) ISBN 0–415–16770–1 (pbk) IN MEMORY OF DICK SPICER, A GOOD FRIEND AND A STIMULATING COLLEAGUE CONTENTS List of illustrations ix Preface xiii Acknowledgements xv 1 Archaeology and computers 1 Data and theory 1 Modelling the past 5 Towards contextuality 9 Theory into practice – the next six chapters 12 2 Survey and prospection 14 Working with aerial photographs 17 Managing AP collections 26 Using satellite imagery 30 A change of scale – geophysical surveys 33 Topographic surveys – working with points and lines 48 Surface survey 69 Towards data integration 77 3 Excavation and computers 78 Background 78 Excavation recording 85 The written record 86 Harris Matrix generation 98 Integrating spatial data 101 Towards information systems 110 4 Beyond excavation 124 Dating and chronology 124 Artefact studies 129 Specialists 142 Modelling, simulation and archaeology 147 Three-dimensional modelling 152 vii CONTENTS 5 Digital landscapes 164 The attraction of GIS within archaeology 164 Predicting the past? 168 Quantifying space 170 Towards digital places 174 The GIS bandwagon 182 6 Preserving and managing evidence of the past 183 CRM and increasing computer usage: an international trend 183 CRM in England: dealing with diversity 198 At the county level 199 At the national level 205 Museums, computers and archaeological collections 211 7 Communicating archaeology 219 Museums into the future 220 Going interactive 222 Interacting world-wide 229 Teaching and learning 231 Research resources 240 Electronic publication 247 8Virtual futures 253 Information as product? 253 Virtuality, the self and culture 260 The past meets the future in a digital present 263 Notes 269 Bibliography 273 Index 293 viii ARCHAEOLOGY AND COMPUTERS ILLUSTRATIONS Figures 1.1 The integration of computers into the hermeneutic spiral showing the area of mediation between the past and the present 7 1.2 A suggested development of archaeological computing showing the relationship between technological and theoretical developments 8 2.1 Manipulation of a digital image by histogram, or contrast, stretching 18–19 2.2 Mapping from aerial photographs 21–23 2.3 A computer-drawn contour plan of Mam Tor hillfort in the Peak District, England 25 2.4 Describing crop-marks within the MORPH system 27 2.5 Output from Photonet showing oblique aerial photographic coverage 28–29 2.6 The use of satellite imagery in the Archaeological Mission of Zeugma Project 31–32 2.7 Grid balancing of geophysical data 34 2.8 Stages in the computer-based analysis and display of resistivity data from Freens Court, Hereford 35–38 2.9 The results of a Ground Penetrating Radar (GPR) survey at Leominster Priory 40–42 2.10 Working with vector data at Alfred’s Castle, Oxfordshire 43–47 2.11 Digital mapping and surveying demonstrated by the COMPASS (now ForeSight) System and the Thailand Archaeometallurgy Project 49–52 2.12 RCHME (now English Heritage) computer-assisted surveying of Pilsdon Pen hillfort, Dorset 55–58 2.13 Surface modelling of a Bronze Age ring cairn on Stapeley Hill, Shropshire with possible ridge and furrow 59 2.14 Experiments in the required density of points in a topographic survey illustrated by the simulated site of Clonehenge 60–61 2.15 Planning the ancient city of Sámárra, Iraq 63–65 2.16 RCHME (now English Heritage) survey of Holne Moor, Dartmoor using Global Positioning System (GPS) technology 66–68 2.17 Surface survey and the Najerilla Project, Spain 71–75 ix ILLUSTRATIONS 3.1 The Archaeology Division Management Information System (ADMIS) of English Heritage 82–84 3.2 Pro-forma recording sheets as data collection devices for computerised databases 87–88 3.3 A simplified data model for recording a part of the written excavation record using a relational database model 91 3.4 From data model to database 92–93 3.5 Data modelling using Entity-Relationship concepts as described in IDEA (the Integrated Database for Excavation Analysis) 95–97 3.6 Harris Matrix generation by computer 99–100 3.7 Linking the site matrix to database records using Gnet 101–102 3.8 Recording three-dimensional coordinates using the 3Space Tracker on excavations 108–109 3.9 Using three-dimensional recording and digital photography to recreate an excavated feature 111 3.10 Excavation recording within an integrated environment, the Integrated Archaeological Database System (IADB) 112–117 3.11 Post-excavation analysis using commercial GIS software 120–122 4.1 Creating a seriated sequence 128 4.2 Calibrating radiocarbon dates using the OxCal program 130–131 4.3 Archaeological illustration using a computer 132–135 4.4 Output in the form of a dendrogram from computer-based classification using Cluster Analysis 138 4.5 Classifying artefacts by computerised shape matching using SMART (a System for Matching ARTefacts) 139 4.6 Early attempts at Artificial Intelligence using the rule-based logic of Expert Systems 141 4.7 An example of Artificial Intelligence using a Hybrid Neural Network 143 4.8 An example of using a GUI (Graphical User Interface) for simplified data entry into a database 145–146 4.9 Computer simulation based on formal modelling 149 4.10 Simple simulation: an exercise in human and computer pattern perception 151 4.11 Stages in the reconstruction modelling of ancient Greek pottery 156–159 4.12 Stages in the reconstruction modelling of ancient buildings 160–162 5.1 Predictive modelling of site location based on the locational attributes of known sites and using GIS software 169 5.2 GIS and landscape analysis, the early example of the Hvar island case-study 171–172 5.3 Visibility around the River Danube, Iron Gates Gorge 177–179 6.1 An example of the relationship between pro-forma recording cards and computerisation within Cultural Resource Management systems 185–186 6.2 Linking a database to digital map data 188–190 x ILLUSTRATIONS 6.3 Different approaches to handling spatial data 192 6.4 ARCHIS the National Archaeological Record of the Netherlands 193–196 6.5 The York Archaeological Assessment (YAA) and the York Environs Project (YEP) 203–204 6.6 The use of GIS at the Royal Commission on the Ancient and Historical Monuments of Scotland (RCAHMS) 208–210 6.7 Structuring data and using information in the Ashmolean Museum Collections Information Database (CID) 214–215 7.1 Aspects of interactivity and hypermedia design 224–225 7.2 Structured interactivity within a museum interactive 228 7.3 The use of CAL (Computer Assisted Learning) in undergraduate teaching 233–234 7.4 Multimedia as a free-standing resource rather than a part of structured learning 237–239 7.5 Catalogues as an electronic research resource 241–242 7.6 The use of Standard Generalized Markup Language (SGML) 248 Table 3.1 Stages in the seamless processing of data from excavation to archiving, publication and access 81 Infoboxes 1 Raster and vector data 14–16 2 CAD and GIS 53–54 3 GPS 69 4 Databases 89–90 5 Archaeological statistics 125–126 6 Modelling and Virtual Reality 152–154 7 Reading GIS in archaeology 167 8 The Internet 220 xi VERSO RUNNING-HEAD xii RECTO RUNNING-HEAD PREFACE Writing a book about computing almost inevitably includes the inherent danger of built-in obsolescence, especially one that takes several years to ‘mature’ as this one has.