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Since its independence in 1965, Singapore has seen unprecedented economic and social improvement, which has also been accompanied by physical growth through land reclamation. This rapid growth, coupled with the increasing cost of land reclamation and a desire to be a City in a Garden, has resulted in competing land-use requirements at the surface. Consequently, Singapore now looks to the subsurface to meet many of its future development needs. A comprehensive understanding of the geology has therefore become critical to Singapore’s continued prosperity and future development. For the last decade, the British Geological Survey has been working with the Geological and Geospatial Development Department of Singapore's Building and Construction Authority to implement a comprehensive urban geological survey and communicate the outcomes to the widest possible stakeholder community in Singapore. Activities within this programme of works included: desk study and literature review; deep borehole drilling and in situ testing; seismic reflection and refractions surveys; field mapping; aerial image analysis; detailed outcrop and borehole logging; a wide range of laboratory analysis testing; 3D geological modelling; comprehensive analysis and interpretation of new and existing data; and training and knowledge exchange. The culmination of this work is a substantially revised interpretation of the geology, including a new International Commission on Stratigraphy (ICS)-compliant stratigraphy and structural framework. The research has been published in six peer-reviewed articles and is now synthesised in a new interactive map and memoir of Singapore geology. A companion volume, Practitioners’ guide to the bedrock geology of Singapore, has also be published to facilitate adoption of the new geological framework by industry professionals. It is the intention of the Building and Construction Authority that the trio of new publications are used by those working in the engineering constru

BGS has been commissioned by Allen Fraser and Jenny Murray, on behalf of Shetland Museum & Archives, to conduct a petrographic examination of sandstone masonry from three churches in Shetland and sandstone bedrock from two historic quarries in Orkney, and use the results to test a hypothesis that the stone forming the Shetland masonry was sourced from Orkney quarries. The client has provided seven samples of sandstone from masonry blocks, and details of the sampled localities. The blocks are believed to originate from three medieval churches in Shetland, but are now spolia (stone fragments removed from one built structure and incorporated in the masonry of another, later structure). All three of the medieval churches were constructed in the C12th and demolished in either the C18th or C19th. Ashlar blocks and rubble from St Magnus’s Church (Tingwall, Mainland) and St Laurence’s Church (Papil, West Burra) were incorporated within the masonry of new churches that were built on the same sites. St Mary’s Church (Ireland, near Bigton, Mainland) was not replaced after demolition, but stone blocks believed to be from the church have been found in the walls of nearby buildings. The client has also provided one sample of sandstone from Head of Holland quarry (Mainland, Orkney). Four samples of sandstone bedrock from the BGS Rock Collection – two from Head of Holland quarry and two from Fersness quarry (Eday, Orkney) – have been included in the assessment, so that the full petrographic character of these two historic quarries can be assessed. Both quarries are sited within bedrock assigned to the Eday Group, a geological formation that crops out exclusively in parts of Orkney. A thin section (a slice of stone cut thin enough to be transparent, so it can be examined by microscope) was prepared from each sample. The petrographic description for each sample includes information from the hand sample and the associated thin section. Brief details of each sample, with a hand sample

This report describes a study designed to devise an appropriate methodology for using a Handheld X-Ray Fluorescence (HH-XRF) instrument for in situ testing of sandstone building stones. HH-XRF is a non-destructive method of compositional analysis that could offer the means to geochemically differentiate different sandstones, and constrain their quarry sources. To examine the potential of HH-XRF for these purposes, a programme of laboratory tests has been conducted on a range of sandstone building stones from the UK. The aims of the test programme were to: develop and refine a robust and fit-for-purpose methodology for gathering, managing, displaying and interpreting compositional data; determine the extent to which sample surface condition and stone texture affect the results; and evaluate whether or not the results can provide a basis for distinguishing different sandstones. The results suggest the instrument can be used to distinguish sandstones (and potentially a wide range of other geological and man-made materials) that are otherwise indistinguishable in the field, and as such the method should find widespread application in disciplines such as building conservation and archaeology.

Determining the provenance of building stone can be important when researching the history of historic structures or identifying suitable substitute stone to use in building repairs. Commonly, however, there is no written record of stone source, and a visual examination alone is inconclusive. In many such situations stone provenance can only be constrained with confidence if the stone has a distinctive property or character that allows it to be distinguished from, or matched with, other stones. A small proportion of stones have one or more genuinely distinctive visual characteristics that uniquely confirm their provenance, but for most stones such distinctive properties, if they exist at all, are cryptic and usually revealed only by microscope examination or bulk chemical analysis. However, collecting and analysing representative hand samples for this purpose can be difficult, timeconsuming and damaging to historic structures. Handheld X-Ray Fluorescence analysis offers the potential to provide bulk composition data without the need to collect physical samples. HH-XRF instruments are lightweight, wireless and portable, and they provide a rapid, non-destructive means of analysing most materials in a wide range of settings. This study has examined the benefits and limitations of the instrument when applied to sandstone building stones from the UK. A programme of laboratory tests has been used to: develop a robust methodology for gathering, managing, displaying and interpreting data; determining the extent to which sample surface condition affects the analytical results; and assessing the degree to which different sandstones can be distinguished on the basis of their bulk composition. The results are promising: the data can be used to compare, distinguish and match visually indistinguishable sandstones (and potentially a wide range of other geological and man-made materials) quickly and easily, and as such the method should find widespread application in disciplines su

Scotland has one of the richest legacies of traditional (pre-1919) buildings and other stone structures of any country in the world, but the building stone industry that created that legacy is now a small fraction of its former size and struggling to survive as the use of imported stone continues to grow. This report presents an objective review of the building stone industry in Scotland today. It includes: a brief synopsis of its history; evidence of its current fragile state, and the threat this poses to the historic and natural environments; an analysis of the potential for the industry to grow, and the benefits that a stronger indigenous industry could bring; a description of factors that are holding back its development (‘barriers to growth’); and a list of practical steps that can be taken by the industry and other stakeholders to encourage and facilitate growth.

This report presents the outcomes of a project commissioned by Historic Scotland to determine, using a combination of archival records and geological evidence, whether blocks of sandstone in Iona Nunnery (a Scheduled Monument on the island of Iona) came from Carsaig quarry (a long-disused quarry on the south coast of Mull). The report also considers the feasibility of sourcing new stone to use in future repairs to the nunnery from Carsaig quarry and from the remains of nearby Carsaig pier. Details of the most suitable commercially available stones from elsewhere in the UK are also provided, should it prove not possible or not practical to obtain new stone from Carsaig quarry or Carsaig pier.

This report describes the outcomes of a project commissioned by Historic Scotland to identify suitable stone to use in forthcoming repairs to the building known as The Engine Shed, in Stirling, which will become Historic Scotland’s National Conservation Centre. A Building Stone Assessment has been conducted on three samples of sandstone supplied by Historic Scotland – two from different parts of The Engine Shed and one from the recently demolished Seaforth Place Bridge in Stirling – with a view to assessing whether stone recovered from the demolished bridge could be considered amongst the closest-matching currently available stones and therefore a suitable replacement stone. This assessment has shown that stone from the bridge is amongst the closest-matching stones, and should provide a good replacement stone for walling and copestones in The Engine Shed provided weathered stone is first removed from the recycled blocks and any blocks required to perform a load-bearing function are subjected to a geotechnical test to confirm they are sufficiently strong. Drumhead sandstone, which is currently quarried near Denny, should also provide a good replacement stone.

Geothermal energy is simply the natural heat that exists within our planet. In some parts of the world the existence of a geothermal energy resource is made obvious by the presence of hot springs, and such resources have been exploited in various ways for millennia. More usually, there is no direct evidence at Earth‘s surface of the vast reservoir of stored heat below, and geothermal energy has remained largely ignored and untapped in most parts of the world. Now, its potential as a renewable source of energy is being recognised increasingly, and technologies and concepts for exploiting it are developing rapidly along two lines: low enthalpy (low temperature) resources, which exploit warm water in the shallow subsurface to provide heat either directly (as warm water) or indirectly (via heat exchange systems); and high enthalpy (high temperature) resources, which yield hot water, usually from deeper levels, that can be used to generate electricity. The potential for harnessing electricity from geothermal energy has long been recognised; the potentially substantial reserves, minimal environmental impact, and capacity to contribute continuously to base load electricity supply make it an extremely attractive prospect. The ongoing drive to develop renewable sources of energy, coupled with anticipated technological developments that will in future reduce the depth at which heat reservoirs are considered economically viable, means there is now a pressing need to know more about the deep geothermal energy potential in Scotland. This report contains the British Geological Survey (BGS) contribution to a collaborative project between AECOM and BGS to produce a qualitative assessment of deep geothermal energy potential in onshore Scotland for the Scottish Government. BGS‘s role is to provide the Stage One deliverable ―Identifying and assessing geothermal energy potential‖, comprising an assessment of areas in Scotland most likely to hold deep geothermal resources based on exist

The British Geological Survey (BGS) has conducted a survey of the building stones and roofing slates in 172 buildings that lie within, and face onto, the Townscape Heritage Initiative (THI) area in Falkirk town centre. The survey was commissioned by Falkirk Council and was conducted by the BGS Building Stone Team in January and February 2013. This report describes the outcomes of the survey. The report also has sections describing a brief assessment of historical quarrying activity in the Falkirk area and the results of stone matching for all the different building stones and slates recorded during the survey. The survey results are presented in this report as a set of maps, but the ‘raw’ survey data have been delivered independently of this report in a Microsoft Excel table and in a shape file suitable for GIS applications. A folder of digital images of the surveyed building elevations has also been delivered independently of this report. Twenty different building stones were recorded in the THI area: thirteen are buff sandstone, two are orange sandstone, one is limestone, and four are granite. All of the buff sandstones were sourced from Carboniferous strata that were laid down between 350 and 300 million years ago. Seven come from quarries in the Midland Valley of Scotland and six are from northern England.

The Cairngorm massif in NE Scotland (Figure 1) is an excellent example of a preglacial upland landscape formed in granite. Glacial erosion in the mountains has been largely confined to valleys and corries (Rea, 1998) and so has acted to dissect a pre-existing upland (Figure 2). Intervening areas of the massif experienced negligible glacial erosion due to protective covers of cold-based ice (Sugden, 1968) and preserve a wide range of pre-glacial and non-glacial landforms and regolith. This assemblage is typical for many formerly glaciated upland and mountain areas around the world. The cliffs that sharply demarcate the edges of glacial valleys and corries allow the main pre-glacial landforms to be easily identified. The former shape of pre-glacial valleys and valley heads can then be reconstructed by extrapolation of contours to provide a model of the pre-glacial relief of the Cairngorms (Thomas et al., 2004). This relief model (Figure 3) provides a basis for understanding the development of the landscape over timescales of many millions of years, including the role of geology, weathering, fluvial erosion and, lately, glacial erosion in shaping the relief.

This report presents a classification of mapped onshore igneous intrusions of the UK that were emplaced during the Phanerozoic Eon, and which are represented in the BGS DiGMapGB-50 model and its equivalent in Northern Ireland. It represents the first significant step towards a comprehensive, unified classification of lithodemic units in the UK, to complement well-advanced efforts to produce a full classification of lithostratigraphical units (set out in the BGS Stratigraphical Framework report series). The structure of the classification and the procedure for assigning formal names to intrusive units follow the proposals of Gillespie et al. (2008). In that scheme, 34 different types of individual intrusions and groupings of intrusions are arranged in a hierarchical parent–child association spanning six formal ranks (Figure 1); Rank 1 is taken to be the ‘highest’ and Rank 6 the ‘lowest’. A further eight types of lithodemic unit are used to classify mapped units that consist mainly of intrusive rock but have a ‘mixed’ character, encompassing a significant proportion of non-intrusive rocks (Figure 1).

Lithodemic units are those mappable geological units that are defined and delimited primarily by their lithological character, and which lack primary stratification. This report sets out proposals for classifying and naming all types of lithodemic unit other than intrusions. The units are organised in two hierarchical chains referred to as tectonometamorphic units and mixed-class units. These proposals complete a comprehensive BGS scheme for classifying and naming lithostratigraphical and lithodemic units, which is presented here in four hierarchical chains spanning up to seven ranks (Table 1). Within the scheme, the seven established types of lithostratigraphical unit (NACSN, 1983; Rawson et al., 2002), thirty-four types of intrusive unit (Gillespie et al., 2008), and twelve types of tectonometamorphic unit (this report) are placed in parallel parent–child chains that straddle the same six ranks (Rank 1 to Rank 6). Each of these three hierarchical chains represents a distinct class of mappable unit. Within each chain, parent units embrace children of the same class (i.e. at lower ranks in the same chain), so the units in each of these three hierarchies are referred to as ‘single-class units’. In the fourth chain (this report), parent units embrace children from two or more of the three hierarchies of single-class units, so the seven types (and four ‘special cases’) of lithodemic unit within it are referred to as mixed-class units. At present, the units in this chain straddle five ranks, one of which is not shared by any of the other chains; additional types of mixed-class unit may be inserted in other ranks of this chain if a need is demonstrated when the scheme is used to classify mapped units. Guidance is given for assigning formal names to tectonometamorphic and mixed-class units. Completion of the scheme means it is now possible to classify and name lithostratigraphical and lithodemic units, separately and in any combination, in any setting, in a systematic and

This report describes the results of a desk-based geodiversity audit of the Cairngorms National Park commissioned by the Cairngorms National Park Authority (CNPA) and jointly funded by the British Geological Survey (BGS). It represents a first pass at selecting the most important localities for Local Geodiversity Sites in the Cairngorms National Park, based on available information and local knowledge of BGS geologists. Thirty-five bedrock geodiversity sites (including 23 Geological Conservation Review Sites) and fifty-four Quaternary sites (including 38 Geological Conservation Review Sites) are proposed as Park geodiversity sites. These sites should not be regarded as the final definitive list, but as a framework to which additional sites can be added as more information becomes available. The main outputs from the project are GIS and database files of the geodiversity sites.

This report describes the geological and geomorphological contribution by BGS to a landscape character assessment of the Cairngorms National Park commissioned by the Cairngorms National Park Authority (CNPA). To underpin assessment and description of landscape character areas, BGS provided bespoke bedrock and superficial deposits/geomorphological ‘character’ maps of the CNP with accompanying descriptive text. The resulting Landscape Character Assessment will be used to inform landscape and land management policy to assist the CNPA and its partners in delivering the four aims of the National Park. It will also help the CNPA ensure that plans and policies conform to the European Landscape Convention.

This report presents a scheme for classifying and naming geological discontinuities and their fillings, and provides guidance for describing discontinuities in rock masses. The scheme is a new BGS corporate standard analogous to more established standards like the BGS Rock Classification Scheme. Its purpose is to provide geologists with the means to collect and store discontinuity and filling data succinctly and consistently, in any setting and at any scale; to supply a set of approved terms and their definitions to the dictionaries that support BGS databases, and to permit BGS staff, customers and other users to better understand BGS outputs that incorporate discontinuity data.

This report describes the current status of the BGS Rock Classification Scheme (RCS) and possible plans for its maintenance and on-going development. It describes the impact of the RCS since publication in 1999, worldwide developments in rock classification and how this affects the standing of the RCS. Options are suggested for ways to update, enhance and maintain the RCS. A detailed review of the existing schemes has been carried out and a plan to amend and improve them is proposed.

The role of Work Package (WP) 2 of the PADAMOT project – ‘Palaeohydrogeological Data Measurements’ - has been to study late-stage fracture mineral and water samples from groundwater systems in Spain, Sweden, United Kingdom and the Czech Republic, with the aim of understanding the recent palaeohydrogeological evolution of these groundwater systems. In particular, the project sought to develop and evaluate methods for obtaining information about past groundwater evolution during the Quaternary (about the last 2 million years) by examining how the late-stage mineralization might record mineralogical, petrographical and geochemical evidence of how the groundwater system may have responded to past geological and climatological changes. Fracture-flow groundwater systems at six European sites were studied: • Melechov Hill, in the Bohemian Massif of the Czech Republic: a shallow (0-100 m) dilute groundwater flow system within the near-surface weathering zone in fractured granitic rocks; • Cloud Hill, in the English Midlands: a (~100 m) shallow dilute groundwater flow system in fractured and dolomitized Carboniferous limestone; • Los Ratones, in southwest Spain: an intermediate depth (0-500 m) dilute groundwater flow system in fractured granitic rocks; • Laxemar, in southeast Sweden: a deep (0-1000 m) groundwater flow system in fractured granitic rocks. This is a complex groundwater system with potential recharge and flushing by glacial, marine, lacustrine and freshwater during the Quaternary; • Sellafield, northwest England: a deep (0-2000 m) groundwater flow system in fractured Ordovician low-grade metamorphosed volcaniclastic rocks and discontinuous Carboniferous Limestone, overlain by a Permo-Triassic sedimentary sequence with fracture and matrix porosity. This is a complex coastal groundwater system with deep hypersaline sedimentary basinal brines, and deep saline groundwaters in crystalline basement rocks, overlain by a shallow freshwater aquifer system. The site was g