G-BASE
Definition
The BGS Geochemical Baseline Survey of the Environment. Soil and stream-sediment samples collected across Britain at roughly one per 2 km2, analysed for a core set of elements by XRF and ICP-MS. The principal regional reference dataset for UK forensic geology.
- Full name
- BGS Geochemical Baseline Survey of the Environment
- Sample density
- Roughly one sample per 2 km2
- Analysis methods
- XRF and ICP-MS
- Coverage
- Across Britain
Common questions
How does an examiner use G-BASE in a forensic geology case?+
Elemental concentrations measured in soil recovered from a suspect, vehicle, or tool are compared against the local G-BASE background values for the area of interest, helping assess whether the sample's composition is consistent with, or stands out from, that region's natural geochemistry.
What is a limitation of relying on G-BASE for source attribution?+
Its sampling density, while dense for a national survey, still averages over a couple of square kilometres, so it can support regional consistency statements but cannot pinpoint an exact field or site the way a targeted local sample comparison can.
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