Water samples have predominantly been collected by the G-BASE (Geochemical Baseline Survey of the Environment) project at an average sampling density of one sample per 1.5 km square. Samples have been collected from approximately 85% of Great Britain but it is only from Wales and Humber-Trent southwards that a wide range of analytes have been determined. Currently G-BASE stream water samples collected from high order streams are determined by ICP-AES for 27 elements - Sr, Cd, Ba, Si, Mn, Fe, P, S (as SO42-), B, Mg, V, Na, Mo, Al, Be, Ca, Zn, Cu, Pb, Li, Zr, Co, Ni, Y, La, K and Cr; and by quadrupole ICP-MS for 24 trace elements - Li, Be, Al, V, Cr, Co, Ni, Cu, As, Rb, Y, Zr, Mo, Ag, Cd, Sn, Sb, Ba, La, Ce, Tl, Pb, Th and U. Automated colorimetric methods are used to determine Cl and NO3- and ion selective electrode is used to determine F. Waters are also analysed for non-purgeable organic carbon (NPOC) to determine dissolved organic carbon content. All samples have routinely been analysed for pH, conductivity and bicarbonate. Much of the UK coverage also includes uranium and fluoride analyses.

This layer of the map based index (GeoIndex) shows the locations where stream sediment samples are collected under the G-BASE (Geochemical Baseline Survey of the Environment) programme at an average density of approximately one site per 1.5 km square. Analytical data for the minus 150 micron fraction of stream sediment samples are available for some or all of the following elements by a variety of analytical methods (now predominantly XRFS): Mg, P, K, Ca, Ti, Mn, Fe, V, Cr, Co, Ba, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Y, Zr, Nb, Mo, Pb, Bi, Th, U, Ag, Cd, Sn, Sb, Cs, La, Ce, Ge, Sc, Se, Br, Hf, Ta, W, Tl, Te and I. Stream sediment samples were also collected by the now defunct MRP programme and analytical data for the minus 150 micron fraction of samples is available for a variety of elements including Ag, As, Au, Ba, Bi, Ca, Ce, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Sn, Sr, Ti, U, V, W, Zn and Zr. Some of the MRP samples may have undergone several stages of analysis, some for inclusion in the G-BASE project. The samples may have been assigned a different sample number but will plot at the same site. Data is available for most Great Britain, apart from some parts of Southern England which have yet to be surveyed.

The map shows the location of excess sample materials from the G-BASE (Geochemical Baseline Survey Of The Environment) geochemistry project:- stream sediments, panned heavy mineral concentrates and soils are stored long term in the National Geoscience Data Centre and are available for use in other projects. The Minerals Programme (incorporating the Mineral Reconnaissance Programme) sample collection contains reference samples of drill cores, rocks, tills, soils, stream sediments and panned concentrates. These samples were collected in the period 1974 - to date in mineralised and potentially mineralised areas of the United Kingdom, principally in the northern and western Britain.

The UTM series of maps are based on 1:250 000 base maps published by the Ordnance Survey. Mapping is divided into squares which cover 1 degree by 1 degree of latitude / longitude in the Universal Transverse Mercator (UTM) projection, and coverage extends offshore and onto the continental shelf. The UTM series are available in three different themes: - Solid geology (complete coverage within the mapped area, including most of the UK continental shelf) - Sea bed sediments (coverage for most offshore areas) - Quaternary geology (coverage for the UK sector of the North Sea, Irish Sea and the Atlantic margin) Also included within this series are two small-scale (1:500 000) bedrock geology maps of the Central Rockall Basin and North Rockall Basin. These maps supersede the older quarter-inch series of maps which were published for England / Wales and Scotland. Geological maps represent a geologist's compiled interpretation of the geology of an area. A geologist will consider the data available at the time, including measurements and observations collected during field campaigns, as well as their knowledge of geological processes and the geological context to create a model of the geology of an area. This model is then fitted to a topographic basemap and drawn up at the appropriate scale, with generalization if necessary, to create a geological map, which is a representation of the geological model. Explanatory notes and vertical and horizontal cross sections may be published with the map. These maps are, for the most part, hard-copy paper records stored in the National Geoscience Data Centre (NGDC) and are delivered as digital scans through the BGS website.

This layer of the map based index (GeoIndex) shows the locations of panned drainage sediment samples. At most drainage sampling sites a panned heavy mineral concentrate is collected from the <2mm sediment fraction using a wooden dulang pan. For the Mineral Reconnaissance Programme these pans would be routinely analysed for mineral exploration purposes. The G-BASE project collects them at every drainage site but does not routinely submit them for chemical analyses and the samples are archived. Usually they are inspected when collected with a hand lens and the presence of mineralisation or contamination is recorded in the site information on field cards. The MRP has collected heavy mineral concentrates from some 33,000 drainage sites and analysed these for a variety of elements (predominantly by XRFS) including Ag, As, Au, Ba, Bi, Ca, Ce, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Sn, Sr, Ti, U, V, W, Zn and Zr.

Data identifying landscape areas (shown as polygons) attributed with geological names. The scale of the data is 1:250 000 scale providing a generalised geology. Onshore coverage is provided for all of England, Wales, Scotland and the Isle of Man. Data are supplied as two themes: bedrock and linear features (faults), there is no superficial, mass movement or artificial theme available onshore at this scale. Bedrock geology describes the main mass of solid rocks forming the earth's crust. Bedrock is present everywhere, whether exposed at surface in outcrops or concealed beneath superficial deposits or water bodies. Geological names are based on the lithostratigraphic or lithodemic hierarchy. This means rock bodies are arranged into units based on rock-type and geological time of formation. Where rock-types do not fit into the lithostratigraphic scheme, for example intrusive, deformed rocks subjected to heat and pressure resulting in new or changed rock types; then their classification is based on their rock-type or lithological composition. This assesses visible features such as texture, structure, mineralogy. Data identifying linear features (shown as polylines) represent geological faults at the ground or bedrock surface (beneath superficial deposits). Geological faults occur where a body of bedrock has been fractured and displaced by large scale processes affecting the earth's crust (tectonic forces). The faults theme defines geological faults (shown as polylines) at the ground or bedrock surface (beneath superficial deposits). The data are available in vector format (containing the geometry of each feature linked to a database record describing their attributes) as ESRI shapefiles and are available under BGS data licence.

This layer of the Map based index (GeoIndex) shows where water wells exist with data available on transmissivity, storativity and discharge/drawdown. These parameters indicate the physical characteristics of the aquifer which can relate to factors such as possible storage capacities or rate of movement of water through the rock.

Data identifying landscape areas (shown as polygons) attributed with geological names and rock type descriptions. The scale of the data is 1:10 000 scale providing bedrock geology. Onshore coverage is partial with approximately 30% of England, Scotland and Wales available in this version 2 data release. BGS intend to continue developing coverage at this scale; current focus is to include all large priority urban areas, along with road and rail transport corridors. Bedrock geology describes the main mass of solid rocks forming the earth's crust. Bedrock is present everywhere, whether exposed at surface in outcrops or concealed beneath superficial deposits or water bodies. The bedrock geology of Great Britain is very diverse and includes three broad classes based on their mode of origin: igneous, metamorphic and sedimentary. The data includes attribution to identify each rock type (in varying levels of detail) as described in the BGS Rock Classification Scheme (volumes 1-3). The bedrock has formed over long periods of geological time, from the Archean eon some 7500 million years ago, to the relatively young Pliocene, 58 million years ago. The age of the rocks is identified in the data through their BGS lexicon name (published for each deposit at the time of the original survey or subsequent digital data creation). For stratified rocks i.e. arranged in sequence, this will usually be of a lithostratigraphic type. Other rock types for example intrusive igneous bodies will be of a lithodemic type. More information on the formal naming of UK rocks is available in the BGS Lexicon of Named Rock Units. Geological names are based on the lithostratigraphic or lithodemic hierarchy. The lithostratigraphic scheme arranges rock bodies into units based on rock-type and geological time of formation. Where rock-types do not fit into the lithostratigraphic scheme, for example intrusive, deformed rocks subjected to heat and pressure resulting in new or changed rock types; then their classification is based on their rock-type or lithological composition. This assesses visible features such as texture, structure, mineralogy. The data are available in vector format (containing the geometry of each feature linked to a database record describing their attributes) as ESRI shapefiles and are available under BGS data licence.

Two geochemical surveys were undertaken in the Solomon Islands between 1976 and 1983 as part of a combined geological mapping and mineral exploration project. The survey of Choiseul and the Shortland Islands was carried out between 1976 and 1979 by the Institute of Geological Sciences (now the British Geological Survey) with support from staff of the Geology Division of the Ministry of Land, Energy and Natural Resources, Solomon Islands. The project produced 12 geological maps at 1:50,000 scale as well as a series of unpublished reports. The survey of the New Georgia Group of islands was undertaken between 1979 and 1983. The project produced 7 geological maps at a scale of 1:100,000 and a regional map of the entire island group at a scale of 1:250,000. A series of multielement geochemical anomaly maps were produced at a scale of 1:100,000 to accompany each of the published geological maps. Master copies of these are held at the Geological Survey in Honiara. Full descriptions of the methods used are described in the margins of the anomaly maps. A total of 8848 stream sediment samples were collected from Choiseul and 7441 from the New Georgia Group, resulting in an average sampling density for the two areas of 2.68 samples per km2 and 1.47 samples per km2 respectively. Sampling in the Shortland Islands was confined to the larger islands, 187 were collected from the Fauro Island group, 148 from Alu and 69 from Mono. The samples were dry sieved and the fraction passing -80 mesh B.S. (177 microns) was analysed. A hot concentrated nitric acid digestion was used prior to analysis by atomic absorbtion spectrophotometry (AAS) for Co, Cu, Pb, Zn, Ni, Ag, and Mn. Samples from the vicinity of the Siruka Ultramafic Complex were determined for Cr by AAS after digestion by a bisulphate fusion technique. Raw data can be obtained from the Geology Division, Ministry of Mines and Energy, PO Box G37, Honiara, Solomon Islands.

This layer of the map based index (GeoIndex) shows the locations of over 12,500 rock samples from the land area of the United Kingdom gathered as part of the Mineral Reconnaissance Programme (MRP). The Mineral Reconnaissance Programme (MRP), funded by the DTI, carried out baseline mineral exploration in Great Britain between 1972 and 1997. The programme has been subsumed into the new BGS Minerals Programme, also funded by the DTI. The rock samples have been analysed for a variety of major and trace elements, mainly by XRF.