OR/18/005 About the Biosphere Isotope Domains GB (V1) dataset

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Evans, J A, Mee, K, Chenery, C A, Cartwright, C E, Lee, K A, and Marchant, A P. 2018. User guide for the Biosphere Isotope Domains GB (Version 1) dataset and web portal. British Geological Survey. (OR/18/005).

Background

Over the last 20 years there has been a huge development in the application of isotopes as tracers for environment, diet and origin, in fauna and flora, both ancient and modern. The principle behind the use of tracers is that elements such as strontium (Sr), oxygen (O), lead (Pb), sulphur (S), carbon (C), and nitrogen (N) are incorporated into tooth enamel (Sr, O, Pb) and bone and dentine collagen (C, N, S) which preserve the life signature post burial. Since the isotope composition of the elements provides information about the environment and diet, the data can be used to constrain these factors in human and animal studies in both ancient and modern studies. However, the method is dependent on the quality of the reference dataset, and such reference data is dispersed, variable and limited in coverage. The aim of this dataset is to create a model for isotope variation across Great Britain that can be developed though time. The Biosphere Isotope Domains GB (V1) dataset and web portal, provide multi-isotope coverage, with documented uncertainties, of the isotope variations in oxygen, strontium, and sulphur. The datasets for Sr and S are available for downloading. In addition, users of the web portal can input their own sample information to determine the regions across Britain best matched to their isotope data.

Who might require these data?

The primary users of this resource will be archaeologists using skeletal analysis to study the geographic origins, movements and diet in past people and populations. The data can also be used in modern studies of bird and fish migration, tracking sources of illegal importation of materials such as hard wood and ivory and authentication of food origins.

What the dataset shows?

The Biosphere Isotope Domains GB (V1) dataset consists of 3 components:

  1. GIS dataset showing the distribution of four domains across Britain (strontium, oxygen (groundwater), oxygen (tooth enamel) and sulphur).
  2. An accompanying web portal for viewing and interrogating the GIS data.
  3. Datasets for strontium and sulphur isotope values, used in deriving the strontium and sulphur domains in the map, are available as associated publications (Evans 2018[1] and Chenery 2018[2]).

The Biosphere Isotope Domains GB (V1) GIS layer contains the following four isotope variables across Britain, presented as 1 km hexagon cells:

  1. Strontium: GB has been subdivided into a number of domains based on the underlying geology and soil parent material (see Strontium isotope domains), with each domain being described by their median strontium isotope value and embedded interquartile ranges.
  2. Oxygen: the oxygen domains show isotope variations in groundwater across Great Britain, as published by Darling et al. (2003)[3].
  3. Oxygen isotope variations in tooth enamel given as the mean and 1SD of ‘local’ populations as described in Evans et al. (2012)[4].
  4. Sulphur: the sulphur domains show isotope variation for a number of key geological units (Chalk, Jurassic Clay and Oolitic Limestone) as well as a Coastal Effects (sea spray) zone. Sulphur data are provided as median isotope values and interquartile ranges with the exception of the Coastal Effects zone which is set at δ34S = 21‰ to 8‰. (NB: There is currently no sulphur data for Scotland).

References

  1. Evans, J A. Biosphere Isotope Domain Map GB (V1): strontium isotope data. DOI 10.5285/ba36de6f-5a20-476b-965d-48182166114a.
  2. Chenery, C A. Biosphere Isotope domain map GB (V1) sulphur isotope data. DOI 10.5285/d023376c-08e3-451b-9d57-de13f14726bd.
  3. Darling, W G, Bath, A H, Talbot, J C. 2003. The O and H stable isotope composition of freshwaters in the British Isles. 2. Surface waters and groundwater. Hydrology and Earth System Sciences Discussions, European Geosciences Union, 2003, 7 (2), pp.183–195.
  4. Evans, J A, et al. 2012. A summary of strontium and oxygen isotope variation in archaeological human tooth enamel excavated from Britain. Journal of Analytical Atomic Spectrometry 27(5): 754–764.