Evaluation of the diagenesis degree in archaeological bones through the Havriliak-Negami equation

Abstract

The study of the mechanical spectroscopy (MS) behaviour in archaeological bone remains samples recovered from the Boca de Lega site (Santa Fe, Argentina) in the temperature range between 450 K and 673 K has been performed. Moreover, to our knowledge the mechanical spectroscopy behaviour as a function of temperature in archaeological bones is for first time reported. The present obtained results are of high value from the archaeological point of view due to they suggest that the bone remains were used probably for culinary activities by the preterite societies that habited this area. Attention is putted in the relaxation processes which appear at around of 510 K and 570 K and their relation with the diagenetic degree of the polypeptide chains of bone remains, inferred from the depositional effects from the soil and the replacement of calcium by sodium and potassium. The damping peaks in the archaeological bones are analysed though the study of the behaviour of the parameters corresponding to the fitted Havriliak-Negami (HN) equations. In addition, samples of fresh bones are also measured by means of MS during successive heating and cooling runs for determining the HN parameters in fresh bones for obtaining a reference state. Results from scanning electron microscopy, energy dispersive spectroscopy, differential thermal analysis and thermogravimetry are also coupled for the discussion of the present work.