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Abstract By 2050, almost 70% of the world’s population will live in towns and cities. This places increasing pressure on land to support development whilst minimising environmental impact and providing long-term sustainability. Prior knowledge of the ground at the planning and development stage is needed to assess its suitability to meet planned subsurface uses and avoid subsurface conflicts at an early stage of design. This research tested the development and application of a 3D engineering geological model and its spatial integration with 2D (hydro)geological datasets to support sustainable development decision-making at Earls Court, London, UK. The 3D engineering geological model consists of seven geological layers extending from Made Ground to the top surface of the Chalk Group. The 3D geological model, and 2D datasets derived from it, are combined with 2D geospatial datasets of urban underground space (UUS) indicators to identify potential uses of urban underground space based on its suitability to do so. This is complimented by a qualitative assessment of the potential subsurface interactions between UUS indicator uses and their implications for delivering the sustainability and energy objectives specified in the Earls Court masterplan. Infiltration sustainable drainage systems (SuDS), ground source heat potential and foundation condition potential were chosen as suitable UUS indictors against which to test the outputs of the methodology. Infiltration SuDS potential was assessed using nationally-available (hydro)geological 2D GIS datasets. Ground source heat potential was assessed using national-available 2D datasets and estimates of thermal properties of each geological layer revealed by the 3D geological model. Potentially suitable foundation conditions were assessed using density data from existing ground investigations and depth of suitable geological layers derived from the 3D geological model. The results reveal constraints for the development of rapid infiltration SuDS but opportunities for bespoke design that considers the thickness of overlying permeable sand and gravel. It identifies the susceptibility of the London Clay Formation to potential volume change and ground movement based on an assessment of its plasticity. Closed-loop ground source heat pump opportunities exist depending on site-specific thermal and hydraulic properties and heat exchange design. Opportunities for the use of the Kempton Park Gravel Member for ground source heating and cooling and combined use of thermal regulation and pile design via thermopiles are identified. A qualitative assessment of potential benefits and conflicts between UUS indicator uses reveals that the Kempton Park Gravel Member and London Clay Formation are likely to have the highest, relative, UUS value. The results demonstrate that there is potential to modify the energy and sustainability components of the Earls Court masterplan prior to invasive ground investigation and development. It is further suggested that this approach can be used to compliment research-tested, semi-qualitative means of valuing UUS indicators. The implications of the methodology for mainstreaming UUS into city masterplans is also assessed. It is concluded that opportunities now exist for the integrated 3D and 2D spatial assessment of UUS indicators into city-scale masterplans. [ABSTRACT FROM AUTHOR]

An assessment of the engineered geothermal system (EGS) resource base that might be available for the generation of electricity for Great Britain has been undertaken by adopting a globally self-consistent protocol that if universally adopted, would allow estimates of EGS made for different countries and regions to be comparable. Maximum estimated temperatures at depths of 5 and 7 km are greater than 200 and 300 °C respectively, a considerable increase over previous estimates. The total heat in place in the basement, to a depth of 9.5 km that is theoretically available for EGS is 357,197 EJ. If it were possible to develop just 2% of this resource, this would be equivalent to 1242 times the final UK energy consumption in 2015. The theoretical and technical potential power has been calculated from the available heat in place. The total technical potential power, to a depth of 6.5 km, is 222,393 MW and represents just 0.4% of the theoretical potential power. Current EGS exploitation is more likely to be restricted to a depths of around 4.5 km and reservoir temperatures greater than 175 °C. In which case technical potential power is mainly restricted to regions of high heat producing granites and represents a total technical potential power of 2280 MW. However, improvements in drilling technology are expected to enable economic drilling to depths of 7 km or greater that will enable EGS exploitation in all regions of Great Britain. [ABSTRACT FROM AUTHOR]

In 2011, the British Geological Survey ( BGS) decided to begin the assembly of a National Geological Model ( NGM) from its existing and on-going geological framework models comprising integrated national crustal, bedrock, and Quaternary models. The bedrock component is the most advanced of these themes and comprises both the calculated models and a complementary network of cross sections that provide a fence diagram for the bedrock geology of Great Britain. This fence diagram, the GB3D_v2012 dataset, is the subject of this article and is available in a variety of formats from the BGS website () as free downloads. It complements the existing 1:625 000 scale map sheets published by BGS utilizing the same colour schema and geological classification. The 121 component cross sections extend to depths between 1.5 and 6 km; they have an aggregate length of over 20 000 km, and they are snapped together at their intersections to ensure total consistency. The sections are guided by the existing BGS geological framework models where they cut through them; they also take account of the vast wealth of published data on the subsurface structure of Britain both from BGS and in the literature. Much of this is in the form of cross sections, contour maps of surfaces, and thicknesses (isopachs). The fence diagram has been built in the Geological Surveying and Investigation in 3D ( GSI3D) software. Utilizing the cross sections and the coverages of the geological units simple 3D volumes can be calculated for the less deformed sedimentary strata. It is envisaged that this dataset will form a useful educational resource for geoscience students and the general public, and also provide the bedrock geology context and structure for regional and catchment scale studies. [ABSTRACT FROM AUTHOR]

In 2011, the British Geological Survey (BGS) decided to begin the assembly of a National Geological Model (NGM) from its existing and on-going geological framework models comprising integrated national crustal, bedrock, and Quaternary models. The bedrock component is the most advanced of these themes and comprises both the calculated models and a complementary network of cross sections that provide a fence diagram for the bedrock geology of Great Britain. This fence diagram, the GB3D_v2012 dataset, is the subject of this article and is available in a variety of formats from the BGS website (www.bgs.ac.uk) as free downloads. It complements the existing 1:625 000 scale map sheets published by BGS utilizing the same colour schema and geological classification. The 121 component cross sections extend to depths between 1.5 and 6 km; they have an aggregate length of over 20 000 km, and they are snapped together at their intersections to ensure total consistency. The sections are guided by the existing BGS geological framework models where they cut through them; they also take account of the vast wealth of published data on the subsurface structure of Britain both from BGS and in the literature. Much of this is in the form of cross sections, contour maps of surfaces, and thicknesses (isopachs). The fence diagram has been built in the Geological Surveying and Investigation in 3D (GSI3D) software. Utilizing the cross sections and the coverages of the geological units simple 3D volumes can be calculated for the less deformed sedimentary strata. It is envisaged that this dataset will form a useful educational resource for geoscience students and the general public, and also provide the bedrock geology context and structure for regional and catchment scale studies. [ABSTRACT FROM AUTHOR]