Isotope Geochemistry

Ancient human mobility at the individual level is conventionally studied by the diverse application of suitable techniques (e.g. aDNA, radiogenic strontium isotopes, as well as oxygen and lead isotopes) to either hard and/or soft tissues. However, the limited preservation of coexisting hard and soft human tissues hampers the possibilities of investigating high-resolution diachronic mobility periods in the life of a single individual. Here, we present the results of a multidisciplinary study of an exceptionally well preserved circa 3.400-year old Danish Bronze Age female find, known as the Egtved Girl. We applied biomolecular, biochemical and geochemical analyses to reconstruct her mobility and diet. We demonstrate that she originated from a place outside present day Denmark (the island of Bornholm excluded), and that she travelled back and forth over large distances during the final months of her life, while consuming a terrestrial diet with intervals of reduced protein intake. We also provide evidence that all her garments were made of non-locally produced wool. Our study advocates the huge potential of combining biomolecular and biogeochemical provenance tracer analyses to hard and soft tissues of a single ancient individual for the reconstruction of high-resolution human mobility.

"The mega-site of Valencina is currently a major focus of interest for the study of Copper Age Iberia. Remarkable megalithic monuments such as La Pastora, Montelirio or Structure 10.042-10.049 at PP4-Montelirio are found alongside hundreds of other features, including pits and large-sized ditches, some of which have yielded evidence of exotic material craftsmanship without parallels in Iberian Late Prehistory which also suggests long-distance contacts. Part of the flourishing experienced by Valencina in the 3rd millennium BC can be explained by its specific geographic location at the mouth of the Guadalquivir river, facing a marine gulf surrounded by lands of high agricultural potential. Other reasons, however, must have accounted for Valencina's growth as a mega-site, including particularly demographic and economic ones. In order to better understand the demographic and subsistence patterns of the communities that lived and/or frequented Valencina, we analysed 29 human and 7 faunal samples for δ 18 O and δ 13 C isotope analyses. The sampling strategy followed is based on a combination of bone and dental tissues. In addition an intra-tooth study was also carried out to observe intra-individual seasonal changes. Overall, this evidence contributes to the study of diet and mobility patterns, which can in turn provide insights of the demography and economy of the communities that used this mega-site. "

Carbonatitic dykes surrounded by K-Na-fenites were discovered in the Pelagonian Zone in Greece. Their carbon-ate portions have an isotopic mantle signature of δ 13 C and δ 18 O ranging from −5.18 to −5.56 (‰ vs. VPDB) and from 10.68 to 11.59 (‰ vs. VSMOW) respectively, whereas their mafic silicate portions have high Nb, Ta and ɛ Nd values, typical of alkaline basalts. Textural relationships hint at a cogenetic intrusion of silicate and carbonate liquids that according to antithetic REE profiles segregated at shallow depths (b0.6 GPa) from a parental melt sourced deeper in the mantle. Fenites bear similar REE abundances to mafic rocks but with high Rb-Ba and low Nb-Ta values. SHRIMP II U-Pb analyses of magmatic zircon cores (δ 18 O = 7.21–7.51) from a carbonate-bearing syenitic amphibolite yielded a Permian intrusion age at 278 ± 2 Ma, considerably older than a Cretaceous (118 ± 4 Ma) greenschist overprint obtained from metamorphic zircon rims (δ 18 O = 6.78–7.02). From 300 to 175 Ma the ɛ Nd of the Pelagonian magmatism rose irregularly to more primitive values attesting to a higher increment of asthenosphere-derived melts. In this context, the carbonatite formed within a transtensional regime of an intra-Pangaea dextral transform fault that signalled the forthcoming penetrating breakoff of the su-percontinent, manifested in the Permo-Triassic.

The research focused on a collection of 37 Late Antique glass fragments, found at the archaeological site of
San Giusto (southern Italy). The analyses performed by SEMEDS, EMPA and LA-ICP-MS showed that all samples are constituted by natron-based soda-lime silica glass and allowed clarifying the distinction between Egyptian HIMT1 and HIMT2 productions. The comparison with the composition of the available glass reference groups was verified through three ternary diagrams (provided here for the first time). The results grouped San Giusto samples into HIMT1 (7 samples), HIMT2 (8 samples) and Levantine (13, plus maybe other 3 samples) productions. A convincing provenance assignment was not feasible for six samples only. The isotopic analyses (87Sr/86Sr and 143Nd/144Nd), performed on a selected set of ten samples, provided further information both in terms of glass technology and provenance, as well as in terms of reference groups characterisation. Particularly, the results demonstrated that nine out of a total of ten samples were made using a limestone-bearing sand enriched with variable amount of marine shells and provided further evidence for the distinction of the HIMT1 and HIMT2 groups; the latter overlapping the Levantine field in the 87Sr/86Sr versus εNd binary diagram. From a technological point of view, the importance of separating the likely ‘fresh’ materials from those intentionally recycled or coloured was put into clear evidence, especially in relation to provenance assignments. Lastly, an interesting technological feature has been observed in sample no. 9, where the composition of the main body of the vessel turned out to be different from that of the handle. This result provided clear evidence of the fact that different glass batches could have been used for the different parts of a single vessel body.

Compilation of geochronological, geochemical, and geophysical data is used to reinterpret Black Sea-Lake level history.The Black Sea-Lake remained fresh during deglaciation until the marine transgression at 9300 calendar years BP.Prior to the transgression, the Black Sea-Lake level was 120 mbsl or lower.The transgression was fast and took no longer than a couple of decades.The salinification that followed took <~1500 years.Our knowledge of rate and processes in which semi-enclosed environments alternate from lacustrine to marine is commonly limited because of the paucity of specific proxies for sea level and salinity. Here we investigate the timing, rate, and key mechanisms involved in the transformation of the previously isolated Black Sea-Lake to the modern partly-enclosed marine sea using a suite of geophysical, geochemical, and geochronological methods.Cores were collected in transects across shelves of Ukraine, Romania, Bulgaria, and Turkey. Biogenic carbonate from these cores was analyzed for radiocarbon and strontium, oxygen, and carbon isotopes. Strontium results indicate that the submergence of the Black Sea shelf at 9300 calendar years BP was caused by the ingress of Mediterranean water and was abrupt, taking < 40 years. The seismic reflection profiles show a uniform drape of subsequent sediment over aeolian dunes indicating a drowning with no time for erosion accompanying the submergence. Moisture measurements beneath the uniform drape indicate that the shelf was dry before submergence and the shoreline of the Preboreal lake may have regressed to beyond 120 mbsl. Mollusks colonized the newly submerged substrate of the inner shelf at the same time as they colonized the outer shelf. The succession of mollusk species with shells whose strontium isotope composition has a marine component indicates a rising salinity. The transformation of the lake to a sea is affirmed by increases in the shells' strontium and oxygen isotopic ratios towards the external ocean value.Radiocarbon years are calibrated to calendar years by tuning the oxygen and carbon isotope composition of the mollusk record to that of the U/Th dated Sofular Cave stalagmites. The match shows a reduction of the lake's prior high reservoir age accompanying the inflow of the Mediterranean water. In 900 years the salinity reached a threshold that excluded all previous Black Sea lacustrine fauna. These results imply that any substantial postglacial submergence of the Black Sea shelves did not occur prior to entry of Mediterranean water.