PINK?book covers (18mm) v2:Layout 1 13-03-12 11:01 AM Page 1 RADIOCARBON DATES RADIOCARBON DATES RADIOCARBON DATES This volume holds a datelist of 882 radiocarbon determinations carried out between 1988 and 1993 on behalf of the Ancient Monuments Laboratory of English Heritage. It contains supporting information about the samples and the sites producing them, a comprehensive bibliography, and two indexes for reference and from samples funded by English Heritage analysis. An introduction provides discussion of the character and taphonomy of the between 1988 and 1993 dated samples and information about the methods used for the analyses reported and their calibration. The datelist has been collated from information provided by the submitters of the samples and the dating laboratories. Many of the sites and projects from which dates have been obtained are published, although, when some of these measurements were produced, high-precision calibration was not possible for much of the radiocarbon timescale. At this time, there was also only a limited range of statistical techniques available for the analysis of radiocarbon dates. Methodological developments since these measurements were made may allow revised archaeological interpretations to be constructed on the basis of these dates, and so the purpose of this volume is to provide easy access to the raw scientific and contextual data which may be used in further research. Alex Bayliss, Alex Christopher Gordon Bayliss, GerryCook, Bronk Ramsey, McCormac, Walker Robert and Otlet, Jill Front cover: The Dover Bronze Age boat under excavation, 1992 (© Canterbury Archaeological Trust Ltd, photography by Andrew Savage) Back cover: Stephen Hoper loading benzene into a high-precision liquid scintillation spectrometer at the Queen’s University, Belfast (© English Heritage, photography by Amanda Grieve) Product Code 51780 ISBN 978-1-84802-229-4 Alex Bayliss, Christopher Bronk Ramsey, Gordon Cook, Gerry McCormac, Robert Otlet, and Jill Walker PINKbook intro v4:PINKbook 13-03-12 11:08 AM Page i RADIOCARBON DATES from samples funded by English Heritage between 1988 and 1993 PINKbook intro v4:PINKbook 13-03-12 11:08 AM Page ii PINKbook intro v4:PINKbook 13-03-12 11:08 AM Page iii RADIOCARBON DATES from samples funded by English Heritage between 1988 and 1993 Alex Bayliss, Christopher Bronk Ramsey, Gordon Cook, Gerry McCormac, Robert Otlet, and Jill Walker PINKbook intro v4:PINKbook 13-03-12 11:08 AM Page iv Published by English Heritage, The Engine House, Fire Fly Avenue, Swindon SN2 2EH www.english-heritage.org.uk English Heritage is the Government’s statutory adviser on all aspects of the historic environment. © English Heritage 2013 All images, unless otherwise specified, are either © English Heritage or © Crown Copyright. NMR.The negative numbers for English Heritage and NMR images are noted in square brackets in the captions where possible. First published 2013 10 9 8 7 6 5 4 3 2 1 ISBN 978-1-84802-229-4 Product Code 51780 British Library Cataloguing in Publication Data A CIP catalogue record for this book is available from the British Library. All rights reserved No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage or retrieval system, without permission in writing from the publisher. Application for the reproduction of images should be made to the National Monuments Record. Every effort has been made to trace the copyright holders and we apologise in advance for any unintentional omissions, which we would be pleased to correct in any subsequent edition of this book. The National Monuments Record is the public archive of English Heritage. For more information, contact NMR Enquiry and Research Services, National Monuments Record Centre, The Engine House, Fire Fly Avenue, Swindon SN2 2EH; telephone (01793) 414600. Edited and brought to publication by David M Jones, Publishing, English Heritage, The Engine House, Fire Fly Avenue, Swindon SN2 2EH. Cover design and page layout by www.farbott.com Indexed by Alan Rutter Printed by 4Edge Ltd, Hockley. www.4edge.co.uk PINKbook intro v4:PINKbook 13-03-12 11:08 AM Page v Contents Radiocarbon Dates funded by English Heritage between 1988 and 1993 by Alex Bayliss . vii Introduction . vii History of this volume. viii Sample selection and characterisation . ix Laboratory methods . xiv Fractionation and radiocarbon ages . xvii Calibration . xvii Quality assurance . xviii Statistical modelling . xxiv Using the datelist . xxv Acknowledgements . xxv Datelist . 1 Bibliography . 241 Index of laboratory codes . 255 General index. 261 v PINKbook intro v4:PINKbook 13-03-12 11:08 AM Page vi vi PINKbook intro v4:PINKbook 13-03-12 11:08 AM Page vii Radiocarbon Dates funded by English Heritage between 1988 and 1993 Introduction had been excavated with public funding over previous decades. Other samples were submitted from archaeological This volume presents a detailed catalogue of the radiocarbon research programmes undertaken by the staff of the Ancient dates funded by English Heritage between April 1988 Monuments Laboratory and their university-based and March 1993. In total, details of 881 determinations contractors. For example, research to investigate whether a are provided. series of plant macrofossils from Leicester: Shires and Only samples from sites in which English Heritage had a Worcester: Deansway (see below, 103 and 231–5), which were formal interest were eligible for dating through the Ancient neither carbonised, mineralised, or waterlogged, were ancient Monuments Laboratory. Often samples came from and preserved by some other means. archaeological excavations funded, wholly or in part, by This datelist also covers a period of transition in the English Heritage. Some samples were from sites excavated by radiocarbon dating programme funded by English Heritage. the in-house archaeological team or on sites in guardianship The last samples were submitted to AERE Harwell in March (Fig 1), but many were from excavations undertaken by others 1989, although processing of these samples and the with funding from the English Heritage Archaeology completion of summary datelists for the journal Radiocarbon Commissions Programme. Many of these sites were excavated continued until the closure of the laboratory in 1990 in advance of development. This volume covers a period of (Hardiman et al 1992; Walker et al 1990; 1991a–b). During transition in English archaeology when funding from 1989 and 1990, conventional radiocarbon dates, measured by developers first became widely available, following the liquid scintillation spectrometry, were provided by The adoption of new planning guidance in the early 1990s Queen’s University, Belfast Radiocarbon Dating Laboratory, (PPG16 1990). Inevitably, post-excavation analysis and including 16 that were dated using the high-precision facility. publication follows on from excavation, however, and so most From 1990, conventional radiocarbon measurements were of the sites included in this volume were excavated before the increasingly undertaken by the Scottish Universities Research implementation of PPG16. and Reactor Centre at East Kilbride, with only high-precision Samples were also submitted from the large-scale work being undertaken in Belfast (Fig 3). archaeological surveys of wetlands which were undertaken During this time the availability of accelerator mass at this time, and from excavations of sites under threat spectrometry increased, from only the handful of samples that (Fig 2). Work also continued on the publication of sites that could be dated each year in the late 1980s to around Fig 1. Excavations at Beeston Castle, Cheshire in 1980 and 1983. (© English Heritage) vii PINKbook intro v4:PINKbook 13-03-12 11:08 AM Page viii Introduction LSC LSCC (high-h- GPCG precision)ion) AAMSAMS Fig 4. Techniques of radiocarbon dating used for the measurements reported in this volume (LSC, liquid scintillation counting; GPC, gas-proportional counting; LSC (high-precision), high-precision liquid scintillation counting; AMS, accelerator mass spectrometry). Fig 2. Bronze Age barrows on Snail Down, Wiltshire showing spectrometry. This new technique met the demand for the the evidence of erosion by military exercises. (© Crown dating of small samples, which had previously been addressed Copyright. NMR) by the miniature gas-proportional counting system at Harwell (2%). Most samples (64%) were dated using liquid scintillation counting, with 16 being dated by high-precision facilities (2%). A general introduction to methods of UtC- UB-UB measuring the radiocarbon content of archaeological samples AA- is provided by Bayliss et al (2004b). OxA-OxxA- History of this volume The compilation of this datelist began in 1994. The majority of the radiocarbon dates included in this GU- volume have not been published previously in datelist form, although many appear in archaeological publications on specific sites. Summary datelists in the journals Radiocarbon HAR- and Archaeometry are available for many of the measurements made at the Harwell Laboratory (Walker et al 1990; 1991a–b; Hardiman et al 1992) and the Oxford Radiocarbon Fig 3. Proportion of radiocarbon measurements included in this Accelerator Unit (Hedges et al 1990; 1991a–b; 1992; 1993; volume processed by each collaborating facility (AA-, Arizona 1994; 1995; 1996; 1997). Accelerator Mass Spectrometer Laboratory; GU-, Scottish In this volume, we have provided as much