Isotopic data relating to the reconstructed mobility of the Middle Oka valley population in the 5th-12th centuries

The method of assessing individual mobility based on the 87Sr86Sr ratios is widely applied in modern archaeological studies. However, there are a number of methodological issues related to collection and estimation of baseline data, identification of diagenetical changes, specific issues of collecting and preparing samples. The paper reviews results of analysis of 37 bioarchaeological samples (cremated bones and tooth enamel from inhumated bodies) and 9 baseline samples (plants and invertebrates) from six cemeteries dating to different periods from the Migration period to the pre-Mongol medieval period which are located in the Oka valley stretching from Kolomna to Serpukhov. The materials come from a number of sites, i. e. Schurovo, Kremenye, Sokolova Pustyn and Luzhki E. The results obtained demonstrate that the variation of the strontium isotopic composition of the natural samples and that of the archaeological samples from all sites of the studied microregion coincide. Presumably, this similarity is due to the fact that geological deposits near the river valley in the studied section of the river are the same. Only four individuals from two sites have 87 Sr 86 Sr ratios that are outside local variability values.