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    The BGS GeoSure Shrink Swell 3D data is a regional hazard susceptibility map that identifies areas of potential shrink–swell hazard, in three dimensional space, at intervals down to 20m in the London and Thames Valley area. Shrinking and swelling clays can change volume due to variation in moisture, which can cause ground movement that may affect many foundations. The data provides an indication of variation in Volume Change Potential (VCP) of shrink-swell clays and is classified on an A-E (low to high) range of hazard susceptibility. BGS GeoSure Shrink Swell 3D for London is part of the BGS GeoSure range of natural subsidence products. It is derived from the BGS Geology 50k data, the BGS London Lithoframe 3D model and the GeoSure v7 Shrink-Swell layer.

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    The data is provided as a single spreadsheet containing geochemical information from three volcanoes (Antuco, Chile; Jocotitlan, Mexico; Montserrat), all of which have been affected by major debris avalanches. The data was collected in order to investigate the long-term evolution of these volcanic systems. In addition, a single worksheet is provided of a summary database of published examples of volcanic debris avalanches. The geochemical data include bulk-rock XRF and ICP-MS data, Sr and Pb isotope measurements, and glass analyses for the Montserrat samples, along with site information for Antuco and Jocotitlan. Additional published analyses for Montserrat is availabile in published papers, as detailed in the spreadsheet.

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    The 5km Hex GS Running Sand dataset shows a generalised view of the GeoSure Running Sand v8 dataset to a hexagonal grid resolution of 64.95km coverage area (side length of 5km). This dataset indicates areas of potential ground movement in a helpful and user-friendly format. The rating is based on a highest level of susceptibility identified within that Hex area: Low (1), Moderate (2), Significant (3). Areas of localised significant rating are also indicated. The summarising process via spatial statistics at this scale may lead to under or over estimation of the extent of a hazard. The supporting GeoSure reports can help inform planning decisions and indicate causes of subsidence. The Running Sand methodology is based on the BGS Digital Map (DiGMapGB-50) and expert knowledge of the behaviour of the formations so defined. This dataset provides an assessment of the potential for a geological deposit to show running sand behaviour under the action of flowing water, a characteristic usually of saturated sand and silt grade material. Complete Great Britain national coverage is available.

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    The 5km Hex GS Shrink Swell dataset shows a generalised view of the GeoSure Shrink Swell v8 dataset to a hexagonal grid resolution of 64.95km coverage area (side length of 5km). This dataset indicates areas of potential ground movement in a helpful and user-friendly format. The rating is based on a highest level of susceptibility identified within that Hex area: Low (1), Moderate (2), Significant (3). Areas of localised significant rating are also indicated. The summarising process via spatial statistics at this scale may lead to under or over estimation of the extent of a hazard. The supporting GeoSure reports can help inform planning decisions and indicate causes of subsidence. The Shrink Swell methodology is based on the BGS Digital Map (DiGMapGB-50) and expert knowledge of the behaviour of the formations so defined. This dataset provides an assessment of the potential for a geological deposit to shrink and swell. Many soils contain clay minerals that absorb water when wet (making them swell), and lose water as they dry (making them shrink). This shrink-swell behaviour is controlled by the type and amount of clay in the soil, and by seasonal changes in the soil moisture content (related to rainfall and local drainage). The rock formations most susceptible to shrink-swell behaviour are found mainly in the south-east of Britain. Clay rocks elsewhere in the country are older and have been hardened by burial deep in the earth and are less able to absorb water. The BGS has carried out detailed geotechnical and mineralogical investigations into rock types known to shrink, and are modelling their properties across the near surface. This research underpins guidance contained in the national GeoSure dataset, and is the basis for our responses to local authorities, companies and members of the public who require specific information on the hazard in their areas. The BGS is undertaking a wide-ranging research programme to investigate this phenomenon by identifying those areas most at risk and developing sustainable management solutions. Complete Great Britain national coverage is available.

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    The 5km Hex GS Running Sand dataset shows a generalised view of the GeoSure Running Sand v7 dataset to a hexagonal grid resolution of 64.95km coverage area (side length of 5km). This dataset indicates areas of potential ground movement in a helpful and user-friendly format. The rating is based on a highest level of susceptibility identified within that Hex area: Low (1), Moderate (2), Significant (3). Areas of localised significant rating are also indicated. The summarising process via spatial statistics at this scale may lead to under or over estimation of the extent of a hazard. The supporting GeoSure reports can help inform planning decisions and indicate causes of subsidence. The Running Sand methodology is based on the BGS Digital Map (DiGMapGB-50) and expert knowledge of the behaviour of the formations so defined. This dataset provides an assessment of the potential for a geological deposit to show running sand behaviour under the action of flowing water, a characteristic usually of saturated sand and silt grade material. Complete Great Britain national coverage is available.

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    The 5km Hex GS Shrink Swell dataset shows a generalised view of the GeoSure Shrink Swell v7 dataset to a hexagonal grid resolution of 64.95km coverage area (side length of 5km). This dataset indicates areas of potential ground movement in a helpful and user-friendly format. The rating is based on a highest level of susceptibility identified within that Hex area: Low (1), Moderate (2), Significant (3). Areas of localised significant rating are also indicated. The summarising process via spatial statistics at this scale may lead to under or over estimation of the extent of a hazard. The supporting GeoSure reports can help inform planning decisions and indicate causes of subsidence. The Shrink Swell methodology is based on the BGS Digital Map (DiGMapGB-50) and expert knowledge of the behaviour of the formations so defined. This dataset provides an assessment of the potential for a geological deposit to shrink and swell. Many soils contain clay minerals that absorb water when wet (making them swell), and lose water as they dry (making them shrink). This shrink-swell behaviour is controlled by the type and amount of clay in the soil, and by seasonal changes in the soil moisture content (related to rainfall and local drainage). The rock formations most susceptible to shrink-swell behaviour are found mainly in the south-east of Britain. Clay rocks elsewhere in the country are older and have been hardened by burial deep in the earth and are less able to absorb water. The BGS has carried out detailed geotechnical and mineralogical investigations into rock types known to shrink, and are modelling their properties across the near surface. This research underpins guidance contained in the national GeoSure dataset, and is the basis for our responses to local authorities, companies and members of the public who require specific information on the hazard in their areas. The BGS is undertaking a wide-ranging research programme to investigate this phenomenon by identifying those areas most at risk and developing sustainable management solutions. Complete Great Britain national coverage is available.

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    The 5km Hex GS Compressible Ground dataset shows a generalised view of the GeoSure Compressible Ground v8 dataset to a hexagonal grid resolution of 64.95km coverage area (side length of 5km). This dataset indicates areas of potential ground movement in a helpful and user-friendly format. The rating is based on a highest level of susceptibility identified within that Hex area: Low (1), Moderate (2), Significant (3). Areas of localised significant rating are also indicated. The summarising process via spatial statistics at this scale may lead to under or over estimation of the extent of a hazard. The supporting GeoSure reports can help inform planning decisions and indicate causes of subsidence. The methodology is based on the BGS Digital Map (DiGMapGB-50) and expert knowledge of the behaviour of the formations so defined. This dataset provides an assessment of the potential for a geological deposit to compress under an applied load, a characteristic usually of superficial deposits such as peat or alluvium. Some types of ground may contain layers of very soft materials like clay or peat. These may compress if loaded by overlying structures, or if the groundwater level changes, potentially resulting in depression of the ground and disturbance of foundations. Complete Great Britain national coverage is available.

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    The 5km Hex GS Soluble Rocks dataset shows a generalised view of the GeoSure Soluble Rocks v8 dataset to a hexagonal grid resolution of 64.95km coverage area (side length of 5km). This dataset indicates areas of potential ground movement in a helpful and user-friendly format. The rating is based on a highest level of susceptibility identified within that Hex area: Low (1), Moderate (2), Significant (3). Areas of localised significant rating are also indicated. The summarising process via spatial statistics at this scale may lead to under or over estimation of the extent of a hazard. The supporting GeoSure reports can help inform planning decisions and indicate causes of subsidence. The Soluble Rocks methodology is based on the BGS Digital Map (DiGMapGB-50) and expert knowledge of the behaviour of the formations so defined. This dataset provides an assessment of the potential for dissolution within a geological deposit. Ground dissolution occurs when certain types of rock contain layers of material that may dissolve if they get wet. This can cause underground cavities to develop. These cavities reduce support to the ground above and can lead to a collapse of overlying rocks. Dissolution of soluble rocks produces landforms and features collectively known as 'karst'. Britain has four main types of soluble or 'karstic' rocks; limestone, chalk, gypsum and salt, each with a different character and associated potential hazards. Engineering problems associated with these karstic rocks include subsidence, sinkhole formation, uneven rock-head and reduced rock-mass strength. Sinkhole formation and subsidence has the potential to cause damage to buildings and infrastructure. Complete Great Britain national coverage is available.

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    **This dataset has been superseded. The latest version is newGeoSure Insurance Product version 8 2020.1** The newGeoSure Insurance Product (newGIP) provides the potential insurance risk due to natural ground movement. It incorporates the combined effects of the 6 GeoSure hazards on (low-rise) buildings. This data is available as vector data, 25m gridded data or alternatively linked to a postcode database - the Derived Postcode Database. A series of GIS (Geographical Information System) maps show the most significant hazard areas. The ground movement, or subsidence, hazards included are landslides, shrink-swell clays, soluble rocks, running sands, compressible ground and collapsible deposits. The newGeoSure Insurance Product uses the individual GeoSure data layers and evaluates them using a series of processes including statistical analyses and expert elicitation techniques to create a derived product that can be used for insurance purposes such as identifying and estimating risk and susceptibility. The Derived Postcode Database (DPD) contains generalised information at a postcode level. The DPD is designed to provide a 'summary' value representing the combined effects of the GeoSure dataset across a postcode sector area. It is available as a GIS point dataset or a text (.txt) file format. The DPD contains a normalised hazard rating for each of the 6 GeoSure themes hazards (i.e. each GeoSure theme has been balanced against each other) and a combined unified hazard rating for each postcode in Great Britain. The combined hazard rating for each postcode is available as a standalone product. The Derived Postcode Database is available in a point data format or text file format. It is available in a range of GIS formats including ArcGIS (*.shp), ArcInfo Coverages and MapInfo (*.tab). More specialised formats may be available but may incur additional processing costs. The newGeoSure Insurance Product dataset has been created as vector data but is also available as a raster grid. This data is available in a range of GIS formats, including ArcGIS (*.shp), ArcInfo coverage's and MapInfo (*.tab). More specialised formats may be available but may incur additional processing costs. Data for the newGIP is provided for national coverage across Great Britain. The newGeoSure Insurance Product dataset is produced for use at 1:50 000 scale providing 50m ground resolution. This dataset has been specifically developed for the insurance of low-rise buildings. The GeoSure datasets have been developed to identify the potential hazard for low-rise buildings and those with shallow foundations of less than 2 m deep. The identification of ground instability and other geological hazards can assist regional planners; rapidly identifying areas with potential problems and aid local government offices in making development plans by helping to define land suited to different uses. Other users of these data may include developers, homeowners, solicitors, loss adjusters, the insurance industry, architects and surveyors.

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    **This dataset has been superseded. The latest version is newGeoSure Insurance Product version 8 2020.1** The newGeoSure Insurance Product (newGIP) provides the potential insurance risk due to natural ground movement at a postcode level. It incorporates the combined effects of the 6 GeoSure hazards on (low-rise) buildings: landslides, shrink-swell clays, soluble rocks, running sands, compressible ground, and collapsible deposits. The newGeoSure Insurance Product evaluates these hazards using a series of processes including statistical analyses and expert elicitation techniques to create a derived product that can be used for insurance purposes such as identifying and estimating risk and susceptibility. The newGeoSure Insurance Product is updated biannually with new releases of Ordnance Survey Code-Point® data (current version used: 2016.3) and is provided for national coverage across Great Britain (not including the Isle of Man). This product is available in a range of GIS formats including Access (*.dbf), ArcGIS (*.shp), or MapInfo (*.tab). The newGeoSure Insurance Product is produced for use at 1:50 000 scale, providing 50 m ground resolution.