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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 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 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 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 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. The storage formats of the data are ESRI and MapInfo but other formats can be supplied.

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    Information for this layer of the map based index (GeoIndex) is taken from the BGS National Landslide Database (NLD), which holds over 15000 records of landslides and is the definitive source of landslide information for Great Britain (excludes Northern Ireland, Isle of Man and the Channel Islands). Each landslide within the National Landslide Database is identified by a National Landslide Database ID number and a point location, as shown on this map. The National Landslide Database ID number represents an individual survey of a landslide, rather than just the landslide itself. This is because there could be several phases of movement within or extensions to the same landslide, particularly if it is a large and complex one. Subsequent surveys of the same landslide may be recorded in the database with the same National Landslide Database ID number but with a new Survey Number. Other information given for each record include; Landslide name, grid reference and whether the landslide record has been validated by the BGS Landslides Team. The point symbols at the designated location do not reflect the size and shape of the corresponding landslide, but just denote the recorded presence of a landslide within a range of accuracy.

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    Data from the British Geological Survey's GeoIndex Hazards theme are made available for viewing here. GeoIndex is a website that allows users to search for information about BGS data collections covering the UK and other areas world wide. Access is free, the interface is easy to use, and it has been developed to enable users to check coverage of different types of data and find out some background information about the data. More detailed information can be obtained by further enquiry via the web site: www.bgs.ac.uk/geoindex.