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A report outlining the geothermal resources of Northern Ireland and identifying their potential role in the development of a sustainable low-carbon energy system, with outline measures that would help to stimulate the development and use of geothermal energy in Northern Ireland. Produced by the Geological Survey of Northern Ireland for the Geothermal Advisory Committee.

This report presents the results of a review of the available porosity and permeability data for potential deep geothermal sandstone reservoirs in Northern Ireland. It is based on information from published and unpublished sources and data collected as part of a GSNI reservoir characterisation project involving a detailed petrography study borehole core and sample material by one of the authors (Dr R Raine). The geology of the north-eastern part of Northern Ireland is characterised by a number of deep sedimentary basins largely concealed below the extensive outcrop of Palaeogene basalts covering most of County Antrim and parts of counties Londonderry, Tyrone, Armagh and Down. The Larne, Lough Neagh, Rathlin and Foyle basins contain thick sequences of sedimentary rocks of Carboniferous to Cretaceous age, including Carboniferous, Permian and Triassic sandstones which are potential hydrocarbon and/or hydrogeothermal reservoirs. Sandstones of similar age and types are being used to produce heat in geothermal energy systems in the Netherlands, Denmark, Germany and Great Britain. There is the potential to develop similar geothermal energy systems in Northern Ireland. Geothermal energy systems can play a role in the decarbonisation of heat and are characterised by their high deliverability and availability approaching 24/7, 365 days a year. Deep geothermal energy systems involve relatively high initial capex associated with the drilling of deep boreholes so it is important to be able to predict accurately the nature and performance of the target geothermal aquifers. In particular, we are interested in the thickness, depth of these sandstones and the temperature of the formation fluids they contain, how much fluid is stored within them and how easily it can move through the rocks. This report focuses on the porosity and permeability of the reservoir rocks, i.e. their storage capacity and fluid flow characteristics. Surface outcrops of these sandstones are very limited in ex

This report is the published product of one of a series of studies covering England, Wales and Northern Ireland commissioned by Radioactive Waste Management (RWM) Ltd. The report provides geological information about Northern Ireland to underpin its process of national geological screening set out in the UK’s government White Paper Implementing geological disposal: a framework for the long-term management of higher activity radioactive waste (DECC, 2014). The report describes geological features relevant to the safety requirements of a geological disposal facility (GDF) for radioactive waste emplaced onshore and up to 20 km offshore at depths between 200 and 1000 m from surface. It is written for a technical audience but is intended to inform RWM in its discussions with communities interested in finding out about the potential for their area to host a GDF.

A geochemical anomaly is a concentration of an element or other constituent in a medium (soil, sediment or surface water) which is unusual in its local setting. Geochemical anomalies may be interesting as indicators of processes such as point contamination or mineralizations. They may therefore be practically useful, indicating sources of pollution or mineral deposits which may be of economic value. As defined, a geochemical anomaly is not merely a large (or small) concentration of a constituent as compared to the marginal distribution. To detect anomalies we must therefore do more than simply map the spatial distribution of the constituent. One proposed approach makes use of a singularity index based on fractal representation of spatial variation. The singularity index can be computed from local concentration measures in nested windows. In this paper we propose an approach to compute threshold values for the index to identify enrichment and depletion anomalies, separate from background information. The approach is based on a mixture model for the singularity index, and it can be supported by computing a distribution for background values of the index by parametric bootstrapping from a robustly-estimated variogram model for the target constituent. This approach is illustrated here using data on elements in the soil in four settings in Great Britain and Ireland.