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.
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.
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.
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.
Profile soil analyses are available from a number of BGS programmes, notably the Mineral Reconnaissance Programme (MRP) and the Geochemical Baseline Survey of the Environment (G-BASE) programme. Sampling depth and range of analytes determined is very variable for the MRP. G-BASE samples are consistently from 35 - 50 cm though since 2003 it has become routine practice in the G-BASE project to collect a top soil and deeper profile sample from the same site but only analyses the top soil and store the profile soil. This also applies in urban areas. The G-BASE profile soils were generally sieved to 150 microns before analysis and determined by XRFS for some or all of: 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. MRP samples can include profile samples from greater than 1 meter collected using a power auger and also include till samples. The G-BASE samples are collected at a density of 1 sample per two square kilometres in rural areas and 4 samples every kilometre square in urban areas. MRP sampling was more site specific generally collecting soil samples along lines at spacing intervals generally 25 - 250 m.