GSI3D model metadata report for HS2 Area 4 (Thorpe Mandeville to Ladbroke) Geology and Regional Geophysics Programme Open Report OR/15/035 BRITISH GEOLOGICAL SURVEY GEOLOGY AND REGIONAL GEOPHYSICS PROGRAMME OPEN REPORT OR/15/035 The National Grid and other Ordnance Survey data © Crown GSI3D model metadata report for Copyright and database rights 2017. Ordnance Survey Licence No. 100021290. HS2 Area 4 (Thorpe Mandeville to Ladbroke) Keywords GSI3D, 3D modelling, Geological Model, HS2. J Thompson National Grid Reference SW corner 450072,241758 NE corner 447441,260924 Edits by H. V. Gow, H. Burke & S. Thorpe Map Sheet 94, 114 and 115, 1:50 000 scale, Warwick, Banbury and Towcester Front cover 3D View of modelled volumes. Bibliographical reference THOMPSON, J. 2017. GSI3D model metadata report for HS2 Area 4 (Thorpe Mandeville to Ladbroke). British Geological Survey Open Report, OR/15/035. 16pp. 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. 3D images BGS © NERC 2014 using GSI3D methodology and software. Maps and diagrams in this book use topography based on Ordnance Survey mapping. © NERC 2017. 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Key as per Table 1. ........... 8 Figure 4: Example of small changes to outcrop, geological units as used in the model calculation. Key as per Table 1. ................................................................................................................... 9 Figure 5: Cross-sections that are used in the model calculation. Shown at x10 exaggeration. Key as per Table 1. ......................................................................................................................... 11 Figure 6 View of fully calculated volume model. Shown at x10 exaggeration. Key as per Table 1. ............................................................................................................................................. 12 2 OR/15/035 Figure 7: Exploded view of HS2 Area 4 Model. Shown at x10 exaggeration. Key as per Table 1. ............................................................................................................................................. 12 TABLES Table 1: List of modelled units ....................................................................................................... 5 Summary This report describes the 3D geological model of HS2 (High Speed 2 rail link) Area 4 (Thorpe Mandeville to Ladbroke), created by Jo Thompson with support from Steve Thorpe. The model was created as part of a set of nine geological models that cover the proposed HS2 rail route from the end of the HS2 London model to Birmingham and the West Coast Main Line near Lichfield. The models were funded from the NERC/BGS Science Budget to promote BGS modelling and geological interpretation services to this important infrastructure project and to test methodologies and procedures for creating geological models by multiple compilers. The report describes the model construction and purpose, with spatial limits and scale, sources of information, data processing, workflow, decisions, assumptions, rules and limitations, together with images of the model. 3 OR/15/035 1 Modelled Volume, Purpose and Scale This model is of the bedrock and superficial geology of an area along the proposed route of the High Speed Rail link between London and Birmingham (HS2). It covers the section of the HS2 route between Thorpe Mandeville in Northamptonshire and Ladbroke in Warwickshire. The bedrock geology of this section of the route comprises Triassic to Middle Jurassic strata, together with superficial deposits