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    The 5km Hex GS Collapsible Deposits dataset shows a generalised view of the GeoSure Collapsible Deposits 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 reports can help inform planning decisions and indicate causes of subsidence. The Collapsible Ground dataset provides an assessment of the potential for a geological deposit to collapse (to subside rapidly) as a consequence of a metastable microfabric in loessic material. Such metastable material is prone to collapse when it is loaded (as by construction of a building, for example) and then saturated by water (as by rising groundwater, for example). Collapse may cause damage to overlying property. The methodology is based on the BGS Digital Map (DiGMapGB-50) and expert knowledge of the origin and behaviour of the formations so defined. It provides complete coverage of Great Britain, subject to revision in line with changes in DiGMapGB lithology codes and methodological improvements.

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    The GeoSure data sets and reports from the British Geological Survey provide information about potential ground movement or subsidence in a helpful and user-friendly format. The reports can help inform planning decisions and indicate causes of subsidence. The methodology is based on BGS DiGMap (Digital Map) and expert knowledge of the behaviour of the formations so defined. This dataset provides an assessment of slope instability. Landslide hazard occurs due to particular slope characteristics (such as geology, gradient, sources of water, drainage, man-made constructions) combining to cause the slope to become unstable. Downslope movement of materials, such as a landslide or rockfall may lead to a loss of support and damage to buildings. Complete Great Britain national coverage is available. The storage formats of the data are ESRI and MapInfo but other formats can be supplied.

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    The dataset describes the potential of bedrock aquifers across Scotland to sustain various levels of borehole water supply, and the dominant groundwater flow type in each aquifer. There are five aquifer productivity classes: very high, high, moderate, low and very low, and three groundwater flow categories: significant intergranular flow; mixed fracture/intergranular flow; and fracture flow. The dataset is a tool to indicate the location and productivity of bedrock aquifers across Scotland. It may have several uses, including in policy analysis and development; to prioritise aquifer and site investigations; to inform planning decisions; and to improve awareness of groundwater in general. The complexity and heterogeneity of geological formations means that the dataset is only a guide. It is designed to be used at a scale of 1:100,000, and not to assess aquifer conditions at a single point.

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    The dataset describes the relative vulnerability of groundwater to contamination across Scotland, by means of five relative classes ranging from 1 (lowest vulnerability) to 5 (highest vulnerability). The dataset is a screening tool that can be used to show the relative threat to groundwater quality from contamination across Scotland. It can provide guidance on the vulnerability of groundwater at a regional scale, highlighting areas at comparatively higher risk of groundwater contamination, and can help indicate the degree of specific site investigation required for a new development or activity. It is designed to be used at a scale of 1:100,000 and should be regarded as a tool to aid groundwater risk assessment rather than a complete solution.

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    The GeoSure data sets and reports from the British Geological Survey provide information about potential ground movement or subsidence in a helpful and user-friendly format. The reports can help inform planning decisions and indicate causes of subsidence. The methodology is based on BGS DiGMap (Digital Map) 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. The storage formats of the data are ESRI and MapInfo but other formats can be supplied.

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    The GeoSure data sets and reports from the British Geological Survey provide information about potential ground movement or subsidence in a helpful and user-friendly format. The reports can help inform planning decisions and indicate causes of subsidence. The methodology is based on BGS DiGMap (Digital Map) 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. The storage formats of the data are ESRI and MapInfo but other formats can be supplied.

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    The BGS groundwater levels dataset is a gridded interpolation of depth to groundwater. The dataset is a raster grid, with 50 × 50 metre pixels holding values that represent the probable maximum depth, in metres, to the phreatic water table. This represents the likely lowest water level, under natural conditions, in an open well or borehole drilled into the uppermost parts of a rock unit. The dataset has been modelled from topography and hydrology, assuming that surface water and groundwater are hydraulically connected. It has not used observations of groundwater level in wells or boreholes directly, but they have been used to validate its performance.

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    The GeoSure data sets and reports from the British Geological Survey provide information about potential ground movement or subsidence in a helpful and user-friendly format. The reports can help inform planning decisions and indicate causes of subsidence. The methodology is based on BGS DiGMap (Digital Map) 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. The storage formats of the data are ESRI and MapInfo but other formats can be supplied.

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    The dataset describes the potential of superficial deposit aquifers across Scotland to sustain various levels of borehole water supply, based on four productivity classes: high; moderate to high; moderate; and a category to signify that a deposit is 'not a significant aquifer'. All superficial deposits aquifers in Scotland are assumed to have primarily intergranular groundwater flow. The dataset is a tool to indicate the location and productivity of superficial deposit aquifers across Scotland. It may have several uses, including in policy analysis and development; to prioritise aquifer and site investigations; to inform planning decisions; and to improve awareness of groundwater in general. The complexity and heterogeneity of geological formations means that the dataset is only a guide. It is designed to be used at a scale of 1:100,000, and not to assess aquifer conditions at a single point.

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    The GeoSure datasets and related reports from the British Geological Survey provide information about potential ground movement due to six types of natural geological hazard, in a helpful and user-friendly format. The reports can help inform planning decisions and indicate causes of subsidence. The Collapsible Ground dataset provides an assessment of the potential for a geological deposit to collapse (to subside rapidly) as a consequence of a metastable microfabric in loessic material. Such metastable material is prone to collapse when it is loaded (as by construction of a building, for example) and then saturated by water (as by rising groundwater, for example). Collapse may cause damage to overlying property. The methodology is based on BGS DiGMapGB-50 (Digital Map) and expert knowledge of the origin and behaviour of the formations so defined. It provides complete coverage of Great Britain, subject to revision in line with changes in DiGMapGB lithology codes and methodological improvements. The storage formats of the data are ESRI and MapInfo but other formats can be supplied.