“Isotope language” of the Alpine Iceman investigated with AMS and MS

Abstract

This paper reviews the use of stable and radioactive isotopes to elucidate an extraordinary archaeological find, the Alpine Iceman “Ötzi”. In 1991 the body of this man was accidentally discovered in an ice-filled depression at a high-altitude mountain pass (Tisenjoch, 3210 m) of the Ötztal Alps. This location at the Austrian–Italian border apparently formed an ancient transition across the Alps from South to North. 14C dating of the body with accelerator mass spectrometry (AMS) revealed that the Iceman had lived some 5200 years ago, within the time period from 3370 to 3100 years BC (Before Christ). A variety of other materials from the discovery site were also dated with 14C AMS suggesting a use of the mountain pass at other time periods, and varying climatic conditions. Ongoing investigations with thermal ionization (TIMS), inductively-coupled plasma (ICP-MS) and gas mass spectrometry include isotope ratios of 18O/ 16O ( δ 18O), 87Sr/ 86Sr and 206Pb/ 204Pb, in order to reveal the Iceman’s origin and migrational behavior. Analyzed samples include tooth enamel, bones and contents of his intestine, which all represent different ontogenetic (developmental) stages. The isotopic composition of the Iceman is compared to both soils from archaeological sites and local waters. Taken together, the results point towards an origin of the Iceman in the Southeast of the finding site, consistent with archaeological and paleobotanical data.