Strontium isotopes overview

Human mobility in recent history is well documented and often related to drastic external changes, including war, famine, and the discovery and exploration of new geographic regions and resources. Reconstruction of mobility patterns in prehistory is thus a crucial part of understanding the forces that drove our ancestors, but it is complicated by the fact that the archaeological evidence becomes scarce as we go back in time. The application of stable isotopes in archaeological research has revolutionised palaeomobility studies by providing independent data, which can be used to evaluate models of migration, trade, and cultural change.
This research project explores the use of strontium isotope ratios (87Sr/86Sr) to trace prehistoric human mobility patterns. Strontium isotope ratios vary across the landscape based on the age and composition of the underlying geology. Through diet humans incorporate strontium into their skeletal tissues such as bones and teeth. Teeth form during childhood and are resistant to weathering and geochemical alteration, often preserving the original isotope values. By comparing the strontium isotope ratios in teeth to the variations of strontium isotopes in the landscape it becomes possible to investigate mobility across geologically different areas between childhood and death.