This report describes the updates made to develop a new Version 2 of the Clyde Gateway Pilot Geological Model

Merritt, J.E.

Monaghan, A.A.

Terrington, R.L.

English

NERC Open Research Archive

     Clyde Gateway Pilot 3D Geological Model, Version 2  Geology and Landscape Programme Commissioned Report CR/12/010         BRITISH GEOLOGICAL SURVEY GEOLOGY AND LANDSCAPE PROGRAMME COMMISSIONED REPORT CR/12/010   The National Grid and other Ordnance Survey data are used with the permission of the Controller of Her Majesty’s Stationery Office. Licence No: 100017897/2012. Keywords Clyde Gateway, 3D  model National Grid Reference SW corner 255000, 660000 Centre point 260000, 665000 NE corner 265000, 670000 Bibliographical reference MONAGHAN, A A, TERRINGTON, R L, AND MERRITT, J E.. 2012.  Clyde Gateway Pilot 3D Geological Model, Version 2. British Geological Survey Commissioned Report, CR/12/010.  10pp. 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 ipr@bgs.ac.uk. 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.  Clyde Gateway Pilot 3D Geological Model, Version 2 A A Monaghan, R L Terrington and J E Merritt   © NERC 2012. All rights reserved Keyworth, Nottingham   British Geological Survey   2012 The full range of our publications is available from BGS shops at Nottingham, Edinburgh, London and Cardiff (Welsh publications only) see contact details below or shop online at www.geologyshop.com The London Information Office also maintains a reference collection of BGS publications, including maps, for consultation. We publish an annual catalogue of our maps and other publications; this catalogue is available online or from any of the BGS shops. 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 surrounding continental shelf, as well as basic research projects. It also undertakes programmes of technical aid in geology in developing countries. The British Geological Survey is a component body of the Natural Environment Research Council. British Geological Survey offices  BGS Central Enquiries Desk Tel 0115 936 3143 Fax 0115 936 3276 email enquiries@bgs.ac.uk  Kingsley Dunham Centre, Keyworth, Nottingham  NG12 5GG Tel 0115 936 3241 Fax 0115 936 3488 email sales@bgs.ac.uk  Murchison House, West Mains Road, Edinburgh  EH9 3LA Tel 0131 667 1000 Fax 0131 668 2683 email scotsales@bgs.ac.uk Natural History Museum, Cromwell Road, London  SW7 5BD Tel 020 7589 4090 Fax 020 7584 8270 Tel 020 7942 5344/45 email bgslondon@bgs.ac.uk 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 BRITISH GEOLOGICAL SURVEY CR/12/010; Version 0.1  Last modified: 2012/02/07 17:14  1  Contents Contents .................................................................................................................................... 1 Summary ................................................................................................................................... 2 1 Bedrock model version 2 ................................................................................................... 2 1.1 Summary model description ....................................................................................... 3 1.2 Model Limitations and Inconsistencies ....................................................................... 5 1.3 Export to ESRI raster grids ......................................................................................... 6 2 Version 2 superficial model ............................................................................................... 6 3 Model uncertainty.............................................................................................................. 6  FIGURES Figure 1 Area of the version 2 model .......................................................................................... 2 Figure 2: Summary stratigraphy of the modelled Carboniferous strata in the Glasgow area. Coal name codes Glasgow Upper coal (GU), Glasgow Ell Coal (GE), Kiltongue Coal (KILC), Knightswood Gas Coal (KDG) ............................................................................................. 3 Figure 3a: Overview of surfaces modelled with data points from boreholes, mine plans and mapped outcrop shown. Figure 3 b): Contours on KILC ....................................................... 4 Figure 4: Overview of faults modelled, looking from above. ....................................................... 5    CR/12/010; Version 0.1  Last modified: 2012/02/07 17:14  2 Summary This report describes the updates made to develop a new Version 2 of the Clyde Gateway Pilot Geological Model. For full details of the models please refer to the report accompanying version 1:   J E Merritt, A A Monaghan, S C Loughlin, M Mansour, B É Ó Dochartaigh and A G Hughes. 2009. Clyde Gateway Pilot 3D Geological and Groundwater Model BGS COMMISSIONED REPORT CR/09/005  1 Bedrock model version 2 A new model version was made to remove minor artefacts and to extend the model to include NS56NE to complete a ‘Central Glasgow’ square (Figure 1).   Figure 1 Area of the version 2 model In detail the Version 2 model: • Fits a revised rockhead model which in some places varies by 10m from the older version  • No new borehole data were entered into BGS.Borehole_Geology or collated from mining data since Version 1  • Faults were extended across NS56NE and also made more consistent with regional modelling work that had taken place since Version 1. The Great Dyke Fault is now called the Blythswood Fault and is taken to cut across the Dechmont Fault.   CR/12/010; Version 0.1  Last modified: 2012/02/07 17:14  3 1.1 SUMMARY MODEL DESCRIPTION  The same six stratigraphic surfaces as in version 1 were modelled (Figs 2 and 3 )    Figure 2: Summary stratigraphy of the modelled Carboniferous strata in the Glasgow area. Coal name codes Glasgow Upper coal (GU), Glasgow Ell Coal (GE), Kiltongue Coal (KILC), Knightswood Gas Coal (KDG)  CR/12/010; Version 0.1  Last modified: 2012/02/07 17:14  4    Figure 3a: Overview of surfaces modelled with data points from boreholes, mine plans and mapped outcrop shown. Figure 3 b): Contours on KILC    CR/12/010; Version 0.1  Last modified: 2012/02/07 17:14  5 34 dipping faults were modelled (Figure 4).  Figure 4: Overview of faults modelled, looking from above. 1.2 MODEL LIMITATIONS AND INCONSISTENCIES Fault geometries which terminate against each other at low angles result in numerous thin ‘slivers’. These are difficult to model satisfactorily and are often poorly constrained by data (e.g. at junction of Blythswood, f38 and f39). There is a small sliver of the Kiltongue Coal surface that penetrates through f38, and should not. Thus thin slivers should be treated as parts of the model with high uncertainty.  Isopach maps and cross-sections through the stacked surfaces and faults highlight inconsistencies caused by lack of data particularly on the more deeply buried parts of KDG and Base ULGS/ILS, or by patchy data coverage on one particular surface (e.g. circular inconsistencies caused by data on a particular coal seam from a particular, localised set of boreholes between GU and GE). For example, variation in general dip between faults 37 and 38 on KILC-ILS-KDG surfaces. Generally the KDG and ILS modelled surfaces are much more uncertain away from their outcrop than the other modelled surfaces, due to lack of data. f40 reverses throw along its length, as on the 10,000 scale map, but the fault dip has consistently been modelled at 60° to the north along the whole structure. The scale of faults modelled is inconsistent. Some smaller faults have been included (f14,15,6) where they constrain the outcrop of the modelled coals on NS66SW. In other areas of the model, only much larger fault structures have been included. Known, smaller faults have been excluded.  Very small areas of bedrock surfaces lie up to 2 metres higher than the rockhead model causing a local crossover. This happens in areas where there are local low points in the higher resolution mesh of the rockhead surface, and there are no TIN points within that area from the lower resolution bedrock mesh (crossovers at TIN points should have been removed). CR/12/010; Version 0.1  Last modified: 2012/02/07 17:14  6  1.3 EXPORT TO ESRI RASTER GRIDS The bedrock model is not included within the Lithoframe Viewer file. The surface grids and a combined fault grid were exported from the modelled TIN’s using a grid spacing of 25m, for loading to ArcGIS.  2 Version 2 superficial model The main edits to the superficial deposits model were: • Node density was increased on cross-sections to improve the interpolation of geological units across the area • The 2D distribution of the units was improved by adding additional holes to the envelopes where the unit was not correlated and using newer functionality in GSI3D v3 for snapping the correlations in section against the surface outcrop and subcrop • Water was removed as a modelled unit from the area.   The modelled surfaces were exported as ESRI grids and are also in the Lithoframe Viewer.  3 Model uncertainty The Version 1 model was supplied with uncertainty layers. Revised layers are not supplied with version 2 since no new data were included in the model. Note that there are no uncertainty maps for NS56NE, the newly modelled NW corner of the model.  

Clyde Gateway Pilot 3D Geological Model. Version 2

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Clyde Gateway Pilot 3D Geological Model. Version 2

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