Permian and Triassic red beds and the Penarth Group of Great Britain

Title page and preliminaries

M. J. Benton, Department of Earth Sciences, University of Bristol, Bristol, UK

E. Cook, Department of Earth Sciences, University of Bristol, Bristol, UK

and

P. Turner, School of Earth Sciences The University of Birmingham Birmingham, UK

GCR Editor: G. Warrington

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

First edition 2002

© 2002 Joint Nature Conservation Committee

Typeset in 10/12pt Garamond ITC by JNCC Printed in Great Britain by CLE Print Limited on Huntsman Velvet 100 gsm. ISBN 1 86 107 493 X

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

1. The copyright of materials derived from the British Geological Survey's work is vested in the Natural Environment Research Council (NERC). No part of these materials (geological maps, charts, plans, diagrams, graphs, cross-sections, figures, sketch maps, tables, photographs) may be reproduced or transmitted in any form or by any means, or stored in a retrieval system of any nature, without the written permission of the copyright holder, in advance.

2. To ensure that copyright infringements do not arise, permission has to be obtained from the copyright owner. In the case of BGS maps this includes both BGS and the Ordnance Survey. Most BGS geological maps make use of Ordnance Survey topography (Crown Copyright), and this is acknowledged on BGS maps. Reproduction of Ordnance Survey materials may be independently permitted by the licences issued by Ordnance Survey to many users. Users who do not have an Ordnance Survey licence to reproduce the topography must make their own arrangments with the Ordnance Survey, Copyright Branch, Romsey Road, Southampton S09 4DH (Tel. 0230 8792913).

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

Benton, M.J., Cook, E. and Turner, P (2002) Permian and Triassic Red Beds and the Penarth Group of Great Britain, Geological Conservation Review Series, No. 24, Joint Nature Conservation Committee, Peterborough.

Benton, M.J., Cook, E. and Turner, P (2002) Lossiemouth Shore and Quarries. In Permian and Triassic Red Beds and the Penarth Group of Great Britain, Geological Conservation Review Series, No. 24, Joint Nature Conservation Committee, Peterborough, pp. 112–16.

Contents

Acknowledgements

Access to the countryside

Preface N.V Ellis

1 General introduction

Scope of the volume

The Permo-Triassic world

Stratigraphy of the Permian and Triassic successions

The Penarth Group

Structural setting

Sedimentology

Red beds of the British Permo-Triassic succession

Palaeontology of the British Permo-Triassic succession

The selection of Permian and Triassic red-bed and Penarth Group GCR sites

2 British Permian red beds

Permian red-bed GCR sites

Red beds of the Moray Firth Basin, north-east Scotland

Introduction

Clashach to Covesea, Morayshire

Masonshaugh Quarries, Morayshire

The Permian red beds of south-west Scotland

Introduction

Corrie Shore to Brodick, Isle of Arran

Hapland Burn, Dumfries and Galloway

Locharbriggs North Quarry, Dumfries and Galloway

The Permian red beds of north-east England

Introduction

Crime Rigg Quarry, County Durham

The Permian red beds of west Cumbria

Introduction

Saltom Bay, Cumbria

The Permian red beds of the Vale of Eden

Introduction

Burrells Quarry, Cumbria

Cowraik Quarry, Cumbria

George Gill, Cumbria

Hilton Beck, Cumbria

Stenkrith Beck, Cumbria

River Belah, Cumbria

The Permian red beds of the English Midlands

Introduction

Sling Common, Hereford and Worcester

Osebury Rock, Hereford and Worcester

Kinver Edge, Staffordshire

The Permian red beds of Devon

Shoalstone, Devon

Saltern Cove, Devon

Roundham Head, Devon

Oddicombe Beach, Devon

Coryton's Cove, Devon

Dawlish, Devon

Orcombe Rocks, Devon

3 British Triassic red beds

British Triassic red-bed GCR sites

The Triassic red beds of the Moray Firth Basin, north-east Scotland

Introduction

Burghead, Morayshire

Lossiemouth Shore and Quarries, Morayshire

The Triassic red beds of the Western Highlands and Islands, and Arran

Introduction

Gruinard Bay, Ross and Cromarty

The Eyre Burn, Island of Raasay, Skye and Lochalsh

Gribun Shore and Crags, Mull, Strathclyde

King's Cave to Drumadoon, Arran, Strathclyde

The Triassic red beds of west Cumbria and the East Irish Sea Basin

Introduction

Fleswick–Saint Bees, Cumbria

Burton Point, The Wirral, Cheshire

Hilbre Island and Hilbre Point, The Wirral, Cheshire

Thurstaston Common, Merseyside

The Dungeon, Merseyside

The Triassic red beds of the Cheshire Basin

Introduction

Dee Cliffs section, Cheshire

Bickerton Hill, Cheshire

Frodsham, Cheshire

Red Brow Cutting, Cheshire

Grinshill Quarries, Shropshire

The Triassic red beds of the western margin of the North Sea Basin

Introduction

Nottingham Castle, Nottingham, Nottinghamshire

Styrrup Quarry, Nottinghamshire

Scrooby Top Quarry, Nottinghamshire

Colwick railway section, Nottinghamshire

The Triassic red beds of the Central Midlands

Introduction

Hulme Quarry Cannock Chase, Staffordshire

Brocton Quarry Cannock Chase, Staffordshire

Wollaston Ridge Quarry Staffordshire

Claverley Road Cutting, Shropshire

Burcot, Hereford and Worcester

Shrewley, Warwickshire

The Triassic red beds of South Wales

Introduction

Sutton Flats, Mid Glamorgan

Barry Island, South Glamorgan

Hayes Point to Bendrick Rock, South Glamorgan

Sully Island, South Glamorgan

The Triassic red beds of Devon

Introduction

Budleigh Salterton, Devon

Ladram Bay to Sidmouth, Devon

4 British Penarth Group sites

Introduction

Stratigraphy

Sedimentology

Palaeontology

Penarth Group sites

The Penarth Group of South Wales

Lavernock to Penarth, near Cardiff, South Glamorgan

Stormy Down, near Bridgend, Mid Glamorgan

The Penarth Group of Gloucestershire, Avon and north Somerset

Wainlode Cliff, Gloucestershire

Westbury Garden Cliff, Gloucestershire

Aust Cliff Avon

Hapsford Bridge, Vallis Vale, near Frome, Somerset

Barnhill Quarry Chipping Sodbury, Avon

Wetmoor, near Wickwar, Avon

Lulsgate Quarry, Avon

The Penarth Group of west Somerset

St Audries Bay, near Watchet, Somerset

Blue Anchor Point, Somerset

The Penarth Group of Devon

Culverhole Point, near Axmouth, Devon

Pinhay Bay, Dorset

References

Glossary

Index

Acknowledgements

Work on this volume was initiated by the Nature Conservancy Council and has been seen to completion by the Joint Nature Conservation Committee on behalf of the three conservation agencies, the Countryside Council for Wales (CCW), English Nature, and Scottish Natural Heritage (SNH). The late Dr George Black, then Head of the Geology and Physiography Section of the Nature Conservancy Council, initiated the GCR project in 1977 and Peter Turner is grateful to him for the invitation to participate in the 'Permian and Triassic Red Beds' part of the project. Thanks are also due to Dr Bill Wimbledon (then Head of the GCR Unit) for his help and support during the site-selection phase of the GCR. Many specialists in addition to the authors have been involved in the assessment and selection of sites; in particular Dr D.I. Whiteside who compiled the 'Rhaetian' GCR site lists. This vital work is gratefully acknowledged.

The present authors were inivited to prepare the text for this volume by JNCC in 1998. In this work, numerous peer reviewers and colleagues made helpful suggestions about drafts, or gave helpful advice, information or permission to use photographs or diagrams. In particular, special thanks go to David Thompson (University of Keele) and Derek Laming, both of whom had previously provided detailed information about the location and interpretation of many key sites in Cheshire and South Devon respectively. Kevin Page (English Nature) provided much useful information for the Styrrup Quarry account. We also thank country conservation agency Earth scientists for their advice: David Evans (English Nature), Colin MacFadyen (SNH), Stewart Campbell and Jon Davies (both CCW).

We also owe grateful thanks to Geoff Warrington who made a tremendous effort in editing and checking the whole text and who gave us invaluable advice throughout the project.

Thanks are also due to the JNCC GCR Publications Editorial and Production Team: Mr Neil Ellis, Publications Manager, Miss Emma Durham and Miss Anita Carter, Production Editors. The diagrams were produced by Xipress IT Solutions of Newmarket by Drs Susanne White and Chris Pamplin.

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 PE1 1UA.

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

Preface

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 Permian and Triassic 'Red Bed' and Penarth Group GCR sites, is the 24th 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 also provides an excellent summary of the sedimentological features and palaeogeographical significance to be found in them, and it 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: owners, 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 1998–2001, 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. Indeed, during the writing of this volume, a small number of sites were identified by the authors as potential GCR sites that should be considered for conservation in order to more fully represent the Permian-Triassic geological history of Britain. These sites are described in this volume and are being investigated for formal addition to the GCR.

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'être of the GCR Series of publications.

N.V. Ellis

GCR Publications Manager May 2001

References