New method of analysing ancient shells

Posted on 3 August 2017

Former York PhD postgraduate develops a new technique for reducing inaccuracies in shell analysis

A former York PhD student has published a paper detailing a new technique for the reconstruction of past environments through shell analysis.

Dr Niklas Hausmann, of the Institute of Electronic Structure and Laser, applied Laser Induced Breakdown Spectroscopy (LIBS) to efficiently map the elemental change throughout the growth increments of three mollusc shells.

The paper, co-authored by Dr Andre Colonese and Dr Harry Robson of BioArch, details how records of past environmental conditions in shell carbonate are usually derived from compositional analysis (i.e. trace elements, stable oxygen, carbon, and nitrogen isotopes) performed along the direction of the shell's growth and thus through time. However, compositional variations within isochronous parts of the shell can distort the environmental record and are difficult to assess without extensively mapping the whole shell.

By assessing the spatial variability of magnesium and calcium intensity ratios, this new method has the potential to mitigate distorted results while increasing the resolution of derived palaeoenvironmental information. The paper concluded that LIBS can also provide a cost-effective alternative for screening shell carbonate records in a fast and highly resolved way. Its application will be beneficial for carrying out more comprehensive studies of a variety of mollusc shells in different localities and environments.

Read the paper in the Journal of Analytical Atomic Spectrometry here: https://doi.org/10.1039/c7ja00131b