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| Titel |
The use of 87Sr/86Sr ratios, Trace Elements and Biological Profiling for Forensic Provenancing of Soils |
| VerfasserIn |
Hilary Bathgate, Andrew Lovett, Jonathan Clarke, Henriette Ueckermann, Jurian Hoogewerff |
| Konferenz |
EGU General Assembly 2011
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 13 (2011) |
| Datensatznummer |
250051438
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| Zusammenfassung |
| Geological samples, including soils, are frequently analysed by forensic laboratories by
comparing a suspect sample to an especially collected control. Soils, as yet, cannot be
matched to a central database, unlike other samples, unless the area in question has already
been identified. There is a need for a method of soil profiling that allows an unknown sample
to be tested and assigned a quantitative likelihood that it originated from a given region.
Spatial models can then be created using geographical information systems (GIS) to house
data relating to multiple variables and be used to map soils across geographical
areas.
Generally, the more variables available with which to compare any two items, the greater the
certainty a forensic analyst can have when asserting their similarity and the same applies to
geological materials. This poster aims to show results of ongoing research at the Centre for
Forensic Provenancing, England, involving the analysis of soil samples collected from across
the county of Norfolk. A number of chemical and biological profiling methods have been
used to build up a unique signature for soils from different locations. 87Sr/86Sr
ratios have been measured using MC-ICP-MS, and trace element concentrations
measured using ICP-MS. The 87Sr/86Sr ratios are significantly different at each of the
sample locations across Norfolk; although there is some variation in the multiple
samples collected at each location this variation is shown to be smaller than the
regional variation. There is a poor correlation between the isotope chemistry of the
topsoil and the underlying geology indicating that other sources such as land use,
vegetation cover and additions to the soil contribute to the 87Sr/86Sr. Therefore,
trace element concentrations have also been used to spatially discriminate samples
and also to investigate the effect of fertilisers on the elemental composition of the
topsoil.
The biological techniques used to aid soil discrimination are pollen analysis and the creation
of vegetation maps for Norfolk showing all of the plant species recorded in the area since
1975; with our results highlighting the correlations between the pollen data and the recorded
plant species, and also the individual and groups of species indicative of the sample areas.
Each additional independent dataset allows for an increasingly unique signature of each
sample to be built up. |
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