FOREGS | Stream Waters Summary Information


As its contribution to the IUGS/IAGC Global Geochemical Baselines Programme, the Forum of European Geological Surveys (FOREGS, now EuroGeoSurveys), through its component surveys, collected various environmental materials (including stream waters) to create geochemical baseline maps for Europe. For the drainage samples and soils this was done at a scale that averages out to about one sample per 4700 km2. A two part geochemical atlas of Europe has been published (Salminen et al., 2005; De Vos et al., 2006) and databases, maps and atlases are freely available from web pages hosted by the Geological Survey of Finland (GTK).

Sample site selection was based on the Global Reference Network (GRN) grid cells developed for the purpose of Global Geochemical Baseline Mapping (Darnley et al., 1995), each cell being 160 x 160 km. The water sampling procedure is described in detail in Salminen et al. (1998) and summarised below. The target was to collect from five "random" sites within each cell.

The British Geological Survey collected a total of sixty stream water samples for FOREGS in the UK between August-October 1998.

Stream Water Sampling and Analytical methodology

At the selected drainage sites running stream water was collected from the small, second order streams (catchment areas <100 km2). During sampling disposable plastic gloves were worn on both hands. The following sub-samples were separately collected at each site:

  • 500 mL polyethylene bottle of unfiltered water for major ion analysis (Ion Chromatography, IC)
  • 100 mL polyethylene bottle filtered (0.45 µm) water for ICP-MS and ICP-AES analysis (acidified)
  • 120 mL NalgeneTM bottle unfiltered water for Hg analysis (acidified) (Hg Analyser)
  • 100 mL polyethylene bottle filtered (0.45 µm) water for dissolved organic carbon analysis (DOC)

The pH and electrical conductivity were measured by meters on location, as was the water alkalinity (determined by titration). Samples were kept cool using a cool box and refrigerator.

The stream waters were analysed at a number of laboratories across Europe by a variety of analytical techniques as listed above.

Data Availability

Geochemical results and maps are easily and freely available from the atlas site hosted by the Finnish Geological Survey (GTK). Data files take the form of a collection of zipped MS Excel files from which individual country subsets can be extracted using the country code field.

References and Links

Darnley, A.G., Bjorklund, A., Bolviken, B. et al. 1995. A Global Geochemical Database for Environmental and Resource Management, Earth Science Series No. 19, UNESCO Publishing, Paris, 122 pp.

De Vos, W. and Tarvainen, T. (ed.) et al. 2006. Geochemical Atlas of Europe. Part 2 - Interpretation of Geochemical Maps, Additional tables, Figures, Maps, and Related Publications. Geological Survey of Finland, Otamedia Oy, Espoo, 692 pp.

Salminen, R., Tarvainen, T., Demetriades, A. et al., 1998. FOREGS Geochemical Mapping Field Manual. Geological Survey of Finland, Guide 47.

Salminen, R. (chief ed.) et al. 2005. Geochemical Atlas of Europe. Part 1 - Background Information, Methodology and Maps. Geological Survey of Finland, Otamedia Oy, Espoo, 525 pp.