Quaternary Research Association Annual Discussion Meeting

Description

Coupled δ18O analysis of tooth and shell carbonates: developing a new approach for reconstructing interglacial climates

The oxygen isotope analysis of rodent teeth has the potential to provide important quantitative records of terrestrial climatic change. Grimes et al. (2003) proposed a novel approach to utilizing this technique for palaeotemperature reconstruction, involving coupling the δ18O values of rodent teeth with that of other coeval biominerals (e.g. mollusc shells). This approach is based on the principle that the δ18O values of mammal teeth are primarily dependent on (and can be used to calculate) the δ18O of local water sources. By combining the δ18O of the water with the δ18O values of mollusc shells, the summer-season temperature at which the shells mineralized can be quantified. Nevertheless, the reliability of this approach for reconstructing Quaternary palaeotemperatures has not yet been tested.

In order to address this problem, this study investigated the δ18O of fossil water vole incisor (Mimomys savini) and mollusc shell (Valvata piscinalis) carbonates from the Middle Pleistocene West Runton Freshwater Bed, Norfolk (UK). The results demonstrate that summer interglacial palaeotemperatures at West Runton, calculated using the coupled δ18O analysis approach, are entirely consistent with existing palaeotemperature reconstructions for the site based on beetle and ostracod assemblages (16-19°C). This suggests that the approach offers great potential for quantifying past interglacial temperatures in Europe, particularly for carbonate-rich sites at which alternative palaeotemperature proxies may be unavailable.

Poster Presentation

Period	6 Jan 2016 → 8 Jan 2016
Event type	Conference
Location	London, United KingdomShow on map