21/2/12 GeolFrameworkPaper_postreview_v2acceptchanges_editorcomments New insights from 3D geological models at analogue CO2 storage sites in Lincolnshire and eastern Scotland, UK. Alison Monaghan1*, Jonathan Ford2, Antoni Milodowski2, David McInroy1, Timothy Pharaoh2, Jeremy Rushton2, Mike Browne1, Anthony Cooper2, Andrew Hulbert2 and Bruce Napier2 1 British Geological Survey, Murchison House, West Mains Road, Edinburgh, EH9 3LA, UK. 2 British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham, NG12 5GG, UK. * Corresponding author (email
[email protected] (Approx.15,600 words in total, 25 figures) SUMMARY: Subsurface 3D geological models of aquifer and seal rock systems from two contrasting analogue sites have been created as the first step in an investigation into methodologies for geological storage of carbon dioxide in saline aquifers. Development of the models illustrates the utility of an integrated approach using digital techniques and expert geological knowledge to further geological understanding. The models visualize a faulted, gently dipping Permo-Triassic succession in Lincolnshire and a complex faulted and folded Devono-Carboniferous succession in eastern Scotland. The Permo-Triassic is present in the Lincolnshire model to depths of -2 km OD, and includes the aquifers of the Sherwood Sandstone and Rotliegendes groups. Model-derived thickness maps test and refine Permian palaeogeography, such as the location of a carbonate reef and its associated seaward slope, and the identification of aeolian dunes. Analysis of borehole core samples established average 2D porosity values for the Rotliegendes (16%) and Sherwood Sandstone (20%) groups, and the Zechstein (5%) and Mercia Mudstone (<10%) groups, which are favourable for aquifer and seal units respectively. Core sample analysis has revealed a complex but well understood diagenetic history.