Hydrogen stable isotope ratios measured in bone collagen from Danish prehistoric samples
Channel: Recording Archaeology
Date: 2017-01-05

Palaeodietary studies commonly analyse 13C and 15N ratios in archaeological bone to infer past dietary habits, although 15N ratios can be influenced by a range of factors other than diet (aridity, manuring, soil conditions, etc.). 2H ratios have been shown to function as trophic level indicator (Birchall et al., 2005; Reynard and Hedges 2008), which can be very useful to aid our interpretation of the 13C and 15N ratios and improve our understanding of palaeodietary habits and subsistence practices. Hydrogen in organics consists of a non-exchangeable and exchangeable fraction; the latter will equilibrate with atmospheric hydrogen with atmospheric hydrogen from water vapor in the lab environment, resulting in meaningless values.This fraction needs to be calculated in order to obtain the non-exchangeable fraction which represents the true values. By applying a 2- stage equilibration method, sample specific and process specific factors influencing exchange rates are compensated for (Meier-Augenstein et al., 2011). Recently developed standards packed in silver tubes containing water of known isotopic composition (Qi et al. 2010) can be analysed alongside solid samples in the same run, which is essential to avoid scale compression. While this method is not novel (Bowen et al., 2005; Meier-Augenstein et al., 2011; 2013), its application with the use of Qi et al.’s standards to archaeological material is new. In this study we subjected bone collagen samples from prehistoric periods from the Limfjord region in northern Denmark spanning the Mesolithic to the Viking Age to a two-stage equilibration method using the silver tube standards to obtain absolute 2H ratios from the non-exchangeable hydrogen fraction.
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Author - van der Sluis, Laura G.1 (Presenting Author) School of Geography,
Archaeology and Palaeoecology, Queen’s University Belfast, United Kingdom
Co-Author(s) - Ogle, N., School of Planning, Architecture and Civil Engineering, Queen’s University Belfast, United Kingdom
Co-Author(s) - Reimer, P.J., School of Geography, Archaeology and Palaeoecology, Queen’s University Belfast, United Kingdom