G-BASE for the UK

G-BASE arsenic data

G-BASE sample (survey points)

Scale N/A
Coverage Partial Great Britain coverage

Ascii grid data (500m cell size).
Printable maps in png format.
Database tables for survey points.


Free grid data available under the Open Government Licence.
Please acknowledge the material.

Survey point data available under licence on request.


The Geochemical Baseline Survey of the Environment (G-BASE) project sets out to map and establish the natural geochemical baseline of the British Isles by collecting stream sediment, water, soil and more recently vegetation samples (at drainage sites) throughout the UK.

The regional geochemical baseline data are important in order to understand our environment and to measure changes, whether they be natural or human-made. This baseline data of the surface environment also allows us to model the migration of elements and provides a reference point against which we can monitor change.

The geochemical baseline stream sediment maps for the UK present data compiled from the BGS's G-BASE project and the Geological Survey of Northern Ireland's TellusNI geochemical survey. The maps are based on analyses of the <150 μm size fraction of up to 110 794 sediment samples collected from first and second order (i.e. small) streams across the UK, that have been analysed for up to 52 major and trace elements (e.g. calcium, magnesium, cobalt, nickel etc). An atlas of the element stream-sediment concentrations for the north of Ireland is available online for viewing as an ebook download.

For the rest of the UK, more detailed information on the G-BASE stream-sediment dataset, including a series of regional geochemical atlases, is available to download.

The data for 18 elements can be downloaded as a set of interpolated concentration maps (37.4 MB) on a 500 m grid across the UK.

Survey data from the G-BASE project is also available under licence.

Stream sediment grids and maps available for download

Element Units Ascii grid (incl. standard deviation) PNG (classified and inferno colour schemes)
Arsenic (As) mg/kg As_grid.zip As_png.zip
Barium (Ba) mg/kg Ba_grid.zip Ba_png.zip
Calcium (CaO) weight % CaO_grid.zip CaO_png.zip
Chromium (Cr) mg/kg Cr_grid.zip Cr_png.zip
Cobalt (Co) mg/kg Co_grid.zip Co_png.zip
Copper (Cu) mg/kg Cu_grid.zip Cu_png.zip
Iron (Fe2O­­3) weight % Fe2O3_grid.zip Fe2O3_png.zip
Lanthanum (La) mg/kg La_grid.zip La_png.zip
Lead (Pb) mg/kg Pb_grid.zip Pb_png.zip
Magnesium (MgO) weight % MgO_grid.zip MgO_png.zip
Manganese (MnO) weight % MnO_grid.zip MnO_png.zip
Nickle (Ni) mg/kg Ni_grid.zip Ni_png.zip
Potassium (K2O) weight % K2O_grid.zip K2O_png.zip
Rubidium (Rb) mg/kg Rb_grid.zip Rb_png.zip
Uranium (U) mg/kg U_grid.zip U_png.zip
Vanadium (V) mg/kg V_grid.zip V_png.zip
Zinc (Zn) mg/kg Zn_grid.zip Zn_png.zip
Zirconium (Zr) mg/kg Zr_grid.zip Zr_png.zip


Contact Digital Data for more information.

Hutton field: well correlation diagram.