Lithostratigraphical framework for Carboniferous successions of Great Britain (Onshore) Research Report RR/07/01 HOW TO NAVIGATE THIS DOCUMENT Bookmarks The main elements of the table of contents are bookmarked enabling direct links to be followed to the principal section headings and sub-headings, figures, plates and tables irrespective of which part of the document the user is viewing. In addition, the report contains links: from the principal section and subsection headings back to the contents page, from each reference to a figure, plate or table directly to the corresponding figure, plate or table, from each figure, plate or table caption to the first place that figure, plate or table is mentioned in the text and from each page number back to the contents page. RETURN TO CONTENTS PAGE BRITISH GEOLOGICAL SURVEY RESEARCH REPORT RR/07/01 Lithostratigraphical framework for Carboniferous successions of Great Britain (Onshore) C N Waters, M A E Browne, M T Dean and J H Powell Contributors M C Akhurst, W J Barclay, J I Chisholm, J R Davies, E C Freshney, The National Grid and other C R Hallsworth, R A Hughes, E W Johnson, B E Leveridge, R W O’B Knox, Ordnance Survey data are used with the permission of the M McCormac, A A McMillan, N J Riley, R A Waters, D Wilson, and B Young Controller of Her Majesty’s Stationery Office. Licence No: 100017897/2007. Keywords Keywords to go here Front cover View of Ingleborough (see p.ii for full caption) Bibliographical reference WAT E R S , C N, BROWNE , M A E, DEAN , M T, and POWELL , J H, 2007. Lithostratigraphical framework for Carboniferous successions of Great Britain (Onshore). British Geological Survey Research Report, RR/07/01. 60pp. Copyright in materials derived from the British Geological Survey’s work is owned by the Natural Environment Research Council (NERC) and/or the authority that commissioned the work. You may not copy or adapt this publication without first obtaining permission. Contact the BGS Intellectual Property Rights Section, British Geological Survey, Keyworth, e-mail [email protected]. You may quote extracts of a reasonable length without prior permission, provided a full acknowledgement is given of the source of the extract. Maps and diagrams in this book use topography based on Ordnance Survey mapping. ISBN 9780 85272 603 7 © NERC 2007. All rights reserved. Keyworth, Nottingham British Geological Survey 2007 BRITISH GEOLOGICAL SURVEY British Geological Survey offices The full range of our publications is available from BGS BGS Central Enquiries Desk shops at Nottingham, Edinburgh, London and Cardiff Tel 0115 936 3143 Fax 0115 936 3276 (Welsh publications only) see contact details below or shop email [email protected] online at www.geologyshop.com Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG Tel 0115 936 3241 Fax 0115 936 3488 The London Information Office also maintains a reference email [email protected] collection of BGS publications, including maps, for consultation. Murchison House, West Mains Road, Edinburgh EH9 3LA Tel 0131 667 1000 Fax 0131 668 2683 We publish an annual catalogue of our maps and other email [email protected] publications; this catalogue is available online or from any of the BGS shops. 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Sowton EX2 7HU Tel 01392 445271 Fax 01392 445371 Maclean Building, Crowmarsh Gifford, Wallingford OX10 8BB Tel 01491 838800 Fax 01491 692345 Geological Survey of Northern Ireland, Colby House, Stranmillis Court, Belfast BT9 5BF Tel 028 9038 8462 Fax 028 9038 8461 www.bgs.ac.uk/gsni/ Parent Body Natural Environment Research Council, Polaris House, North Star Avenue, Swindon SN2 1EU Tel 01793 411500 Fax 01793 411501 www.nerc.ac.uk Website www.bgs.ac.uk Shop online at www.geologyshop.com front cover Ingleborough from Chapel-le-Dale [SD 7510 7707]. The limestone pavement in the foreground is in the Asbian Danny Bridge Limestone Formation of the Great Scar Limestone Group. The overlying Brigantian Alston Formation of the Yoredale Group forms the lower slopes of the hill. The Main Limestone, the top of which is taken at the top of the Alston Formation, forms the lowermost main crag. The capping of the hill, at 724 m OD, is formed by the Lower Howgate Edge Grit, the unconformable base of which forms the base of the Millstone Grit Group. BGS photograph (P005452) taken in September 1973. Contents Summary vi 7 South Wales–Bristol 31 7.1 Avon Group 31 1 Introduction 1 7.2 Pembroke Limestone Group 31 1.1 Tectonic setting 1 7.3 Marros Group 35 1.2 Palaeogeography 3 7.4 South Wales Coal Measures Group 36 2 Principal lithofacies 6 7.5 Warwickshire Group 37 2.1 Continental and peritidal facies 6 8 South-west England (Culm Basin) 38 2.2 Heterolithic clastic and nonmarine carbonate 8.1 Tamar Group 38 facies 6 8.2 Exmoor Group 40 2.3 Open marine, platform and ramp carbonates 6 8.3 Hyner Mudstone and Trusham Mudstone 2.4 Hemipelagic facies 6 formations 40 2.5 Mixed shelf carbonate and deltaic (Yoredale) 8.4 Teign Valley Group 40 facies 6 8.5 Chudleigh Group 42 2.6 Fluviodeltaic (Millstone Grit) facies 8 8.6 Laneast Quartzite Formation 42 2.7 Fluviodeltaic (Coal Measures) facies 8 8.7 Holsworthy Group 42 2.8 Alluvial (Barren Measures) facies 8 2.9 Volcanic facies 8 References 44 3 Lithostratigraphical framework 9 Appendix 1 Lithostratigraphical hierarchy of the Carboniferous strata of the UK 49 4 Midland Valley of Scotland 11 Appendix 2 Chronostratigraphical zonation for the 4.1 Inverclyde Group 11 Carboniferous 56 4.2 Strathclyde Group 11 4.3 Clackmannan Group 11 4.4 Scottish Coal Measures Group 13 FIGURES 4.5 Bathgate Group 13 4.6 Correlation with central and northern North 1 Principal structural features of the British Isles 2 Sea 13 2 Palaeogeographical reconstructions for the Carboniferous of the British Isles 4 5 Northern England 15 3 Schematic graphic log summarising the nine main 5.1 Inverclyde Group 15 lithofacies 7 5.2 Ravenstonedale Group 15 4 Extent of Carboniferous deposits and location of regions 5.3 Border Group 17 discussed in text 10 5.4 Great Scar Limestone Group 18 5 Lithostratigraphical nomenclature, Midland Valley of 5.5 Yoredale Group 19 Scotland 12 5.6 Millstone Grit Group 20 6 Lithostratigraphical nomenclature, Northern 5.7 Pennine Coal Measures Group 20 England 16 5.8 Warwickshire Group 20 7 Lithostratigraphical nomenclature, Central England and 5.9 Correlation with the northern Irish Sea 20 North Wales 23 5.10 Correlation with the Mid North Sea High and 8 Lithostratigraphical nomenclature, south Wales and southern North Sea 21 southern England 32 6 Central England and North Wales 22 9 Lithostratigraphical nomenclature, south-west England 6.1 North Wales ‘Basement Beds’ 22 (Culm Basin) 39 6.2 Clwyd Limestone Group 22 6.3 Peak Limestone Group 24 TABLES 6.4 Bowland High Group 24 6.5 Concealed Tournaisian to Visean carbonates 25 1 Chronostratigraphical framework for the Carboniferous 6.6 Craven Group 25 of England and Wales 56 6.7 Millstone Grit Group 26 2 Dinantian biostratigraphal zonations 57 6.8 Pennine Coal Measures Group 27 3 Namurian, chronostratigraphical units and main 6.9 Warwickshire Group 28 biozones 58 6.10 Correlation with the southern Irish Sea 29 4 Westphalian chronostratigraphy and biostratigraphical 6.12 Correlation with the southern North Sea 29 zonation 60 iii Preface The Stratigraphy Committee of the British Geological scheme proposed by the SFC that aims to rationalise group Survey (BGS) is undertaking a review of stratigraphical and formation nomenclature for the Carboniferous of the classification for all parts of Great Britain. Several entire onshore area of Great Britain. The study draws upon Stratigraphical Framework Committees (SFC) have been published SFC reports for the Midland Valley of Scotland established to review problematical issues for various parts (Browne et al., 1999) and the red-bed successions of the of the stratigraphical column. Each SFC has the following Pennine Basin (Powell et al., 2000). The report identifies a terms of reference: group framework based upon the identification of nine major lithofacies across Great Britain. Regional group names are 1 to review the lithostratigraphical nomenclature of proposed, recognising that each lithofacies may have designated stratigraphical intervals for a given region, accumulated in more than one isolated depositional area. The identifying problems in classification and correlation report provides guidance to formation nomenclature for each 2 to propose a lithostratigraphical framework down to group, indicating criteria for rationalisation of existing formation level nomenclature where necessary. Existing names are used 3 to organise peer review of the scheme wherever appropriate, although where formation names have 4 to present the results in a document suitable for not previously existed, the report proposes a new nomenclature. publication The report aims to provide an overview of the framework for 5 to ensure that full definitions of the lithostratigraphical the Carboniferous of Great Britain.