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The Construction of a Bedrock Geology Model for the UK: UK3D V2015

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The Construction of a Bedrock Geology Model for the UK: UK3D V2015 The construction of a bedrock geology model for the UK: UK3D_v2015. Geology and Regional Geophysics and Energy and Waste Programmes BGS Open Report OR/15/069 BRITISH GEOLOGICAL SURVEY GEOLOGY AND REGIONAL GEOPHYSICS AND ENERGY AND WASTE PROGRAMMES BGS OPEN REPORT OR/15/069 The construction of a bedrock geology model for the UK: UK3D_v2015 The National Grid and other Ordnance Survey data © Crown Copyright and database rights 2015 are used with the permission of the Controller of Her Majesty’s C.N. Waters, R. L. Terrington, M. R. Cooper, R. J. Raine & S. Stationery Office. Thorpe Licence No: 100021290 . Keywords: 3D Model, Cross- sections, bedrock geology, United Kingdom Front cover The UK3D_v2015 bedrock model Frontispiece The coded borehole sticks that inform the UK3D_v2015 model Bibliographical reference WATERS, C. N. TERRINGTON, R., COOPER, M. R., RAINE, R. B. & THORPE, S. 2015. The construction of a bedrock geology model for the UK: UK3D_v2015. British Geological Survey Report, OR/15/069 22pp. 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. © NERC 2015. All rights reserved Keyworth, Nottingham British Geological Survey 2015 BRITISH GEOLOGICAL SURVEY The full range of our publications is available from BGS shops at British Geological Survey offices Nottingham, Edinburgh, London and Cardiff (Welsh publications only) see contact details below or shop online at www.geologyshop.com BGS Central Enquiries Desk Tel 0115 936 3143 Fax 0115 936 3276 The London Information Office also maintains a reference collection of BGS publications, including maps, for consultation. email [email protected] We publish an annual catalogue of our maps and other publications; this catalogue is available online or from any of the Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG BGS shops. Tel 0115 936 3241 Fax 0115 936 3488 email [email protected] The British Geological Survey carries out the geological survey of Great Britain and Northern Ireland (the latter as an agency service for the government of Northern Ireland), and of the Murchison House, West Mains Road, Edinburgh EH9 3LA surrounding continental shelf, as well as basic research projects. Tel 0131 667 1000 Fax 0131 668 2683 It also undertakes programmes of technical aid in geology in email [email protected] developing countries. The British Geological Survey is a component body of the Natural Natural History Museum, Cromwell Road, London SW7 5BD Environment Research Council. Tel 020 7589 4090 Fax 020 7584 8270 Tel 020 7942 5344/45 email [email protected] Columbus House, Greenmeadow Springs, Tongwynlais, Cardiff CF15 7NE Tel 029 2052 1962 Fax 029 2052 1963 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 OR/15/069Draft 1.1 Last modified: 2016/02/09 08:50 Contents Contents .......................................................................................................................................... 2 Executive Summary ...................................................................................................................... 2 1 Background to the study ........................................................................................................ 3 2 Evolution of the national bedrock model ............................................................................. 3 3 Datasets used in the UK3D_v2015 Model ............................................................................ 6 3.1 Digital Terrain Model ..................................................................................................... 6 3.2 Geological Map data ....................................................................................................... 6 3.3 Structural contour plots at regional scale ....................................................................... 8 3.4 1:50 000 Map Sheet Cross-Sections ............................................................................... 8 3.5 Legacy BGS 3D Model Data .......................................................................................... 9 3.6 Boreholes ...................................................................................................................... 11 3.7 Geophysical data ........................................................................................................... 14 4 Model workflow .................................................................................................................... 14 5 Metadata ............................................................................................................................... 18 6 Model rules, use, limitations and uncertainty ................................................................... 20 6.1 Model rules ................................................................................................................... 20 6.2 Use of the model ........................................................................................................... 20 6.3 Limitations .................................................................................................................... 20 6.4 Model uncertainty ......................................................................................................... 21 7 Model availability ................................................................................................................. 21 8 References ............................................................................................................................. 21 Executive Summary This report is available for download on the BGS UK3D web page to allow the reader to better understand the context and development of UK3D, a national network, or ‘fence diagram model’, of bedrock geology cross-sections. It also explains the development of the metadata underpinning the model and therefore supports use and understanding of UK3D. The pre-existing BGS GB3D model provided the only nationally consistent representation of the bedrock geology of Great Britain to depths of at least 1 km. The latest version of this model was released in 2014 as the GB3D_v2014 and accompanying report (Mathers et al. 2014b). However, the existing GB3D_v2014 model lacked equivalent scale presentation of a fence diagram model for Northern Ireland. It was recognised that in order to provide comparable geological information across the United Kingdom it was necessary to upgrade the model to a UK3D fence diagram model incorporating Northern Ireland, with rigorous peer review performed to enable an enhanced dataset. 2 OR/15/069Draft 1.1 Last modified: 2016/02/09 08:50 The objective of this study was therefore to further develop the GB3D model, outlined by Mathers et al. (2014a and b), into a UK3D model by the incorporation of 36 deep boreholes and a framework of 15 cross-sections for Northern Ireland. The appropriate applications for the revised model are for geoscience communication and education to illustrate the national and regional bedrock geology of the United Kingdom to a depth of at least 1 km with an intended resolution of use in the 1:250 000 to 1:1 million scale range. Limitations inherent in the model preclude such applications as detailed geological assessments, resource-reserve estimation and exploration, and any representation or use outside the intended resolution range. The new model produced by this study UK3D_v2015 supersedes the earlier 2014 version for England and Wales, for which areas of the fence diagrams remain the same. The Scottish portion of the model remains unchanged from the earlier 2012 version. The new dataset is a wholly owned BGS product and as with its forerunners it is freely available from the BGS website http://bgs.ac.uk as downloads in a variety of formats. 1 Background to the study The pre-existing GB3D model provided the only nationally consistent representation of the bedrock geology of Great Britain to depths of at least 1 km. The latest version of this model was released in 2014 as the GB3D_v2014 and accompanying report (Mathers et al. 2014b). However, the existing GB3D_v2014 model lacked equivalent scale presentation of a fence diagram model for Northern Ireland. It was recognised that in order to provide comparable geological information across the United Kingdom it was necessary to upgrade the model to a UK3D_v2015 fence diagram model incorporating Northern Ireland, with rigorous peer review performed to enable an enhanced dataset. The scope of this latest phase of work was as follows: develop revisions to the national Geological Vertical Section (GVS), the summary of the geological succession displayed in the model, to incorporate
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