Mobility and palaeodietary reconstructions from combined δ88Sr and 87Sr/86Sr analysis with focus on Slovenian cemeteries

Radiogenic strontium isotope ratios (87Sr/86Sr) have been widely applied to the archeological study of landscape
use. Vast amounts of isoscapes created in the past decade are used to studying past populations’ mobility. Slovenia,
as a crossroads country of Europe, is an excellent target for investigation. Thousands of cremated and inhumated
remains buried in Slovenia’s ancient cemeteries give access to a millenium’s worth of European history, stretching
from the late bronze age to the region’s conquest by the Roman empire in the late iron age (LIA).
While 87Sr/86Sr ratios are relatively static on the strontium path from bedrock, through soil, to plants, δ88Sr can vary
depending on multiple processes, including chemical and biological processes. The δ88Sr analysis in this study focuses
on a better understanding of bioavailable strontium. These analyses will help investigate the limitations of 87Sr/86Sr
datasets, and help to curtail them by using δ88Sr to better understand chemical and biological processes that affect
exogenic strontium. The interpretation of 87Sr/86Sr ratios is based on local stratigraphy and is limited regarding
the influence of weathering, sea spray, and soil contamination. This study shows the significance of adding δ88Sr to
available baselines and isotopic maps for a better understanding of the exogenous strontium cycle. This tackles the
question of sampling strategies regarding isotope mapping for future studies. This allows a first-principles trace from
bedrock to teeth, refining isotope mapping to help discriminate between landscape use, mobility and migration.
δ88Sr can be combined with Sr and Ca concentration measurements to provide further insights into physiological
and dietary impacts on tissue Sr. Previous studies have shown that δ88Sr are linked to changes in trophic levels. Therefore,
differences in δ88Sr may allow for better understanding of paleodietary choices of consumed goods.