British Middle Jurassic stratigraphy

B.M. Cox^* and M.G. Sumbler

^*formerly of the British Geological Survey Keyworth, Nottingham

GCR Editor:

D. Skevington

Published by the Joint Nature Conservation Committee, Monkstone House, City Road, Peterborough, PE1 1JY, UK

First edition 2002

0 2002 Joint Nature Conservation Committee

Typeset in 10/12pt Garamond ITC by JNCC

Printed in Great Britain by CLE Ltd on 100 gsm Silverblade Matt.

ISBN 1 86107 479 4.

A catalogue record for this book is available from the British Library.

Apart from any fair dealing for the purposes of research or private study, or criticism or review, as permitted under the UK Copyright Designs and Patents Act, 1988, this publication may not be reproduced, stored, or transmitted, in any form or by any means, without the prior permission in writing of the publishers, or in the case of reprographic reproduction only in accordance with the terms of the licences issued by the Copyright Licensing Agency in the UK, or in accordance with the terms and licences issued by the appropriate Reproduction Rights Organization outside the UK. Enquiries concerning reproduction outside the terms stated here should be sent to the GCR Team, JNCC.

The publisher makes no representation, express or implied, with regard to the accuracy of the information contained in this book and cannot accept any legal responsibility or liability for any errors or omissions that may be made.

British Geological Survey and Ordnance Survey copyright protected materials.

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3. Permission to reproduce BGS materials must be sought in writing from the Intellectual Property Rights Manager, British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG (Tel. 0115 936 3331).

4. The National Grid is used on diagrams with the permission of the Controller of Her Majesty's Stationery Office, © Crown copyright licence no. GD 27254X/01/00.

Recommended example citations

Cox, B.M. and Sumbler, M.G. (2002) British Middle Jurassic Stratigraphy, Geological Conservation Review Series, No. 26, Joint Nature Conservation Committee, Peterborough.

Cox, B.M. (2002) Peashill Quarry, Dorset. In British Middle Jurassic Stratigraphy (eds B.M. Cox and M.G. Sumbler), Geological Conservation Review Series, No. 26, Joint Nature Conservation Committee, Peterborough, pp. 45–7.

Contents

Acknowledgements

Access to the countryside

Preface N.V. Ellis

1 General introduction to the Aalenian to Callovian stratigraphy of Great Britain

B.M. Cox

Introduction

Palaeoenvironment and palaeogeography

The Middle Jurassic outcrop

Stratigraphical nomenclature

Middle Jurassic fauna and flora

GCR site selection

Volume structure

2 The Middle Jurassic stratigraphy of Wessex

B.M. Cox and K.N. Page

Introduction B.M. Cox

Shipmoor Point–Butterstreet Cove and Tidmoor Point–East Fleet Coast, Dorset B.M. Cox and K.N. Page

Crookhill Brickpit, Dorset K.N. Page

Ham Cliff, Redcliff Point, Dorset K.N. Page

Burton Cliff and Cliff Hill Road Section, Dorset B.M. Cox

Watton Cliff, Dorset B.M. Cox

Peashill Quarry, Dorset B.M. Cox

Horn Park Quarry, Dorset B.M.Cox

Conegar Hill, Dorset B.M. Cox

Ryewater, Corscombe, Dorset K.N. Page

Seavington St Mary Quarry, Somerset B.M. Cox

Troll Quarry, Dorset B.M. Cox

Bradford Abbas Railway Cutting, Dorset B.M. Cox

Louse Hill Quarry, Dorset B.M. Cox

Halfway House Cutting and Quarry, Dorset B.M. Cox

Sandford Lane Quarry, Dorset B.M. Cox

Frogden Quarry, Dorset B.M. Cox

Goathill, Dorset B.M. Cox

Holway Hill Quarry, Dorset B.M. Cox

Milborne Wick Section, Somerset B.M. Cox

Laycock Railway Cutting, Somerset B.M. Cox

Shepton Montague, Somerset B.M. Cox

Godminster Lane Quarry and Railway Cutting, Somerset B.M. Cox

Bruton Railway Cutting, Somerset B.M. Cox

Doulting Railway Cutting, Somerset B.M. Cox

Vallis Vale, Somerset B.M. Cox

Hinton Hill, Wellow, Somerset B.M. Cox

Hinton Charterhouse, Somerset B.M. Cox

Gripwood Quarry, Wiltshire B.M. Cox

3 The Middle Jurassic stratigraphy of the Cotswolds

M. G. Sumbler, B.M. Cox, R.J Wyatt and KN. Page

Introduction B.M. Cox

Barns Batch Spinney and South Main Road Quarry, Somerset B.M. Cox

Brown's Folly, Somerset R.J. Wyatt

Corsham Railway Cutting, Wiltshire R.J. Wyatt

Kellaways–West Tytherton, Wiltshire K.N. Page and B.M. Cox

Lower Stanton St Quintin Quarry and Stanton St Quintin Motorway Cutting, Wiltshire R.J. Wyatt

Hawkesbury Quarry, Gloucestershire M.G. Sumbler

Nibley Knoll, Gloucestershire M.G. Sumbler

Veizey's Quarry, Gloucestershire R.J. Wyatt

Kemble Cuttings, Gloucestershire M.G. Sumbler

Woodchester Park Farm, Gloucestershire R.J. Wyatt

Minchinhampton, Gloucestershire R.J. Wyatt and M.G. Sumbler

Leigh's Quarry, Gloucestershire M.G. Sumbler

Fort Quarry Gloucestershire M.G. Sumbler

Haresfield Hill, Gloucestershire M.G. Sumbler

Frith Quarry, Gloucestershire M.G. Sumbler

Swift's Hill, Gloucestershire M.G. Sumbler

Knap House Quarry Gloucestershire M.G. Sumbler

Crickley Hill, Gloucestershire M.G. Sumbler

Leckhampton Hill, Gloucestershire M.G. Sumbler

Foss Cross, Gloucestershire M. G. Sumbler

Stony Furlong Railway Cutting, Gloucestershire M.G. Sumbler

Rolling Bank Quarry, Gloucestershire M.G. Sumbler

Hampen Railway Cutting, Gloucestershire M.G. Sumbler

First Cutting West of Notgrove, Gloucestershire M. G. Sumbler

Harford Cutting, Gloucestershire M.G. Sumbler

Huntsman Quarry, Gloucestershire M.G. Sumbler

Jackdaw Quarry, Gloucestershire M.G. Sumbler

Snowshill Hill (Hornsleasow Quarry), Gloucestershire M.G. Sumbler

Cross Hands Quarry, Warwickshire M.G. Sumbler

Sharps Hill, Oxfordshire M.G. Sumbler

Hook Norton, Oxfordshire R.J. Wyatt

Horsehay Quarry, Oxfordshire R.J. Wyatt and M.G. Sumbler

Ditchley Road Quarry, Oxfordshire R.J. Wyatt

Stonesfield, Oxfordshire R.J. Wyatt

Shipton-on-Cherwell Cement Works and Whitehill Farm Quarry Gibraltar,

Oxfordshire R.J. Wyatt

4 The Middle Jurassic stratigraphy of the East Midlands

B.M. Cox, M. G. Sumbler, R.J. Wyatt and K.N. Page

Introduction B.M. Cox and M.G. Sumbler

Woodeaton, Oxfordshire R.J. Wyatt

Ardley Cuttings and Quarries, Oxfordshire M.G. Sumbler and R.J Wyatt

Stratton Audley, Oxfordshire, R.J. Wyatt and M.G. Sumbler

Blisworth Rectory Farm, Northamptonshire R.J. Wyatt and M.G. Sumbler

Roade Railway Cutting, Northamptonshire R.J. Wyatt and M.G. Sumbler

Irchester Old Lodge Pit and Irchester Country Park, Northamptonshire R.J. Wyatt and M.G. Sumbler

Finedon Gullet, Wellingborough, Northamptonshire R.J. Wyatt

Cranford St John, Northamptonshire R.J. Wyatt

Thrapston, Northamptonshire R.J. Wyatt, K.N. Page, M.G. Sumbler and B.M. Cox

Peterborough Brickpits, Cambridgeshire K.N. Page

Collyweston, Northamptonshire B.M. Cox

Ketton Quarry Rutland M.G. Sumbler

Clipsham Quarry Rutland M.G. Sumbler

Castle Bytham, Lincolnshire M.G. Sumbler

Sproxton Quarry Leicestershire M.G. Sumbler

Copper Hill, Lincolnshire M.G. Sumbler

Metheringham, Lincolnshire M.G. Sumbler

Greetwell Quarry Lincolnshire M.G. Sumbler

Cliff Farm Pit, East Riding B.M. Cox

Manton Stone Quarry East Riding B.M. Cox

Eastfield Quarry; East Riding B.M. Cox

Drewton Lane Pits, East Riding K.N. Page and B.M. Cox

5 The Middle Jurassic stratigraphy of North Yorkshire B.M. Cox and K.N. Page

Introduction B.M. Cox

Whitwell Quarry North Yorkshire B.M. Cox and M.G. Sumbler

Gristhorpe Bay, Yons Nab and Red Cliff–Cunstone Nab, North Yorkshire B.M. Cox and K.N. Page

Osgodby Point, North Yorkshire K.N. Page

South Toll House Cliff and North Bay, Scarborough, North Yorkshire K.N. Page

Hackness Rock Pit, North Yorkshire K.N. Page

Havern Beck, Saltergate, North Yorkshire K.N. Page

Hudson's Cross Crags, Newton Dale, North Yorkshire K.N. Page

Fairy Call Beck, North Yorkshire K.N. Page

Iron Scar-Hundale and Hundale Point–Scalby Ness, North Yorkshire B.M. Cox

Blea Wyke, North Yorkshire B.M. Cox

Hawsker Bottoms, North Yorkshire B.M. Cox

6 The Middle Jurassic stratigraphy of Scotland B.M. Cox, K.N. Page and N. Morton

Introduction B.M. Cox

Brora (Bathonian), Sutherland B.M. Cox

Brora (Callovian), Sutherland K.N. Page

Cadh'-an-Righ, Ross-Shire K.N. Page

Isle of Eigg B.M. Cox

Elgol–Glen Scaladal, Isle of Skye B.M. Cox

North Elgol Coast, Isle of Skye K.N. Page

Dun Skudiburgh, Isle of Skye B.M. Cox

Duntulm (Cairidh Ghlumaig and Lon Ostatoin), Isle of Skye B.M. Cox

Staffin Bay, Isle of Skye B.M. Cox

Staffin, Isle of Skye K.N. Page

Valtos, Isle of Skye B.M. Cox

Bearreraig Bay, Isle of Skye N. Morton

Beinn na Leac, Isle of Raasay N. Morton

References

Glossary

Fossil index

General index

Acknowledgements

Compilation of this volume by the authors began in 1995 as a contract between the British Geological Survey (BGS) and the Joint Nature Conservation Committee (JNCC), but completion of the work has extended well beyond the original tenure of that contract. The volume comprises a description of sites originally selected for the Geological Conservation Review (GCR) in the 1980s by C.F. Parsons (Aalenian–Bajocian GCR 'Block'), D.W. Cripps (Bathonian GCR 'Block') and K.L. Duff (Callovian GCR 'Block').

At the instigation of the JNCC, Dr Kevin N. Page (formerly with English Nature) prepared initial drafts of the Callovian sites; he acknowledges constructive comments from Prof. J.H. Callomon, Dr K.L. Duff and Dr J.K. Wright. We thank Dr Page and the other contributors (Dr M.J. Barker (University of Portsmouth), Dr N. Morton (formerly at Birkbeck College, University of London) and RJ. Wyatt (formerly with the British Geological Survey)) for their passive forbearance, and Dr D. Skevington (the GCR editor) for his support and encouragement.

Information from unpublished theses is, where possible, quoted with the permission of the authors and/or their host universities; these include J.E. Andrews (University of Leicester, 1984), M. Ashton (University of Hull, 1977), MJ. Bradshaw (University of Oxford, 1978), D.W. Cripps (University of Aston, 1986), S. Gowling (University of Hull, 1987), J.P. Harris (University of Leicester, 1984), S. Holloway (University of Keele, 1981), S.E. Livera (University of Leeds, 1981), C.F. Parsons (University of Keele, 1980) and H.S. Torrens (University of Leicester, 1966). In addition, other individuals and museum curators have imparted information about particular specimens or localities, notably Phil Powell (University Museum, Oxford) and John Crossling (formerly of the Warwickshire Museum).

For original photographic material, we thank Bob Chandler (Figure 2.19) and (Figure 2.28), Dr Keith Duff (Figure 2.8), Prof. John Hudson (Figure 6.40) and Dr Paul Taylor (on behalf of The Natural History Museum; (Figure 2.22), (Figure 3.12), (Figure 5.18) and (Figure 5.19). Prof. Hudson has provided helpful comments as both colleague and referee. To anyone whose contribution we have inadvertently failed to acknowledge, please accept our apologies. We have endeavoured to ensure a uniformity of style and fact; in any editing or rewriting of contributions, we take full responsibility for changes thereby made. Readers are referred to the forthcoming second edition of the Geological Society of London's publication on the correlation of Jurassic rocks in the British Isles for an update on British Middle Jurassic stratigraphy.

The present volume has been seen to completion by the JNCC on behalf of the three conservation agencies, the Countryside Council for Wales, English Nature, and Scottish Natural Heritage. Thanks are due to the JNCC GCR Publications Editorial and Production Team: Neil Ellis (GCR Publications Manager), Emma Durham and Anita Carter (Production Editors). The diagrams were produced by J S Publications of Newmarket. Where the content of illustrations has been replicated or modified from the work of others, appropriate acknowledgements are given in the captions. The National Grid is used on diagrams with the permission of the Controller of Her Majesty's Stationery Office, © Crown copyright licence no. GD 27254X/01/00. Photographs are accredited in the captions.

Access to the countryside

This volume is not intended for use as a field guide. The description or mention of any site should not be taken as an indication that access to a site is open. Most sites described are in private ownership, and their inclusion herein is solely for the purpose of justifying their conservation. Their description or appearance on a map in this work should not be construed as an invitation to visit. Prior consent for visits should always be obtained from the landowner and/or occupier.

Information on conservation matters, including site ownership, relating to Sites of Special Scientific Interest (SSSIs) or National Nature Reserves (NNRs) in particular counties or districts may be obtained from the relevant country conservation agency headquarters listed below:

Countryside Council for Wales, Plas Penrhos, Ffordd Penrhos, Bangor, Gwynedd LL57 2LQ.

English Nature, Northminster House, Peterborough PEI 1UA.

Scottish Natural Heritage, 12 Hope Terrace, Edinburgh EH9 2AS.

Preface

Frontispiece. Portraits of William Smith, Sydney Saory Buckman, Lindall Richardson and William Jocelyn Arkell

There is such a diversity of rocks, minerals, fossils and landforms packed into the piece of the Earth's crust we call 'Britain' that it is difficult not to be impressed by the long, complex history of geological change to which they are testimony. But if we are to improve our understanding of the nature of the geological forces that have shaped our islands, further unravel their history in 'deep time' and learn more of the history of life on Earth, we must ensure that the most scientifically important of Britain's geological localities are conserved for future generations to study, research and enjoy. Moreover, as an educational field resource and as training grounds for new generations of geologists on which to hone their skills, it is essential that such sites continue to remain available for study. The first step in achieving this goal is to identify the key sites, both at national and local levels.

The GCR, launched in 1977, is a world-first in the systematic selection and documentation of a country's best Earth science sites. No other country has attempted such a comprehensive and systematic review of its Earth science sites on anything near the same scale. After over two decades of site evaluation and documentation, we now have an inventory of over 3000 GCR sites, selected for 100 categories covering the entire range of the geological and geomorphological features of Britain.

This volume, detailing the Middle Jurassic stratigraphy GCR sites, is the 26th to be published in the intended 42-volume GCR series. Not only does it contain the descriptions of key localities that will be conserved for their contribution to our understanding of the stratigraphy of rocks of this age, but it also provides an excellent summary of the palaeontological and sedimentological features, and palaeogeographical significance to be found in them; it also outlines the research that has been undertaken on them. The book will be invaluable as an essential reference book to those engaged in the study of these rocks and will provide a stimulus for further investigation. It will also be helpful to teachers and lecturers and for those people who, in one way or another, have a vested interest in the GCR sites: land owners and occupiers, planners, those concerned with the practicalities of site conservation and indeed the local people for whom such sites are an environmental asset. The conservation value of the sites is mostly based on a specialist understanding of the stratigraphical, palaeontological and sedimentological features present and is therefore, of a technical nature. The account of each site in this book ends, however, with a brief summary of the geological interest, framed in less technical language, in order to help the non-specialist. The first chapter of the volume, used in conjunction with the glossary, is also aimed at a less specialized audience. This volume is not intended to be a field guide to the sites, nor does it cover the practical problems of their ongoing conservation. Its remit is to put on record the scientific justification for conserving the sites.

This volume deals with the state of knowledge of the sites available at the time of writing, in 1995–2001, and must be seen in this context. Stratigraphy, like any other science, is an ever-developing pursuit with new discoveries being made, and existing models are subject to continual testing and modification as new data come to light. Increased or hitherto unrecognized significance may be seen in new sites, and it is possible that further sites worthy of conservation will be identified in future years.

There is still much more to learn and the sites described in this volume are as important today as they have ever been in increasing our knowledge and understanding of the geological history of Britain. This account clearly demonstrates the value of these sites for research, and their important place in Britain's scientific and natural heritage. This, after all, is the raison d''etre of the GCR Series of publications.

N.V. Ellis, GCR Publications Manager May 2002

References