Provenancing wood used in the Norse Greenlandic settlements: A biogeochemical study using hydrogen, oxygen, and strontium isotopes

A growing number of studies strive to examine wooden archaeological remains recovered from Norse sites in the North Atlantic, contributing to a better understanding of patterns in both wood exploitation and woodland management. Despite the limited diversity and abundance of trees in the North Atlantic islands, the Medieval Norse kept using wood in most everyday activities including the construction and repair of buildings and boats, the production of artifacts and tools, and as a source of fuel. The proximity of the Greenland settlements with the northeastern American coast, puts them at the forefront in the exploration and exploitation of remote resource regions. While some species may have arrived both as driftwood or imported material, there is currently no method to conclusively identify archaeological wood remains as driftwood. Here, we use biogeochemical analysis of stable hydrogen (δ²H), stable oxygen (δ¹⁸O), and radiogenic strontium (⁸⁷Sr/⁸⁶Sr) isotopes in soil, water, and modern plant samples from various sites in Greenland and Canada to characterize expected local isotopic baselines. While ⁸⁷Sr/⁸⁶Sr isotope ratios do not provide a clear distinction between the regions of interest, δ²H and δ¹⁸O ratios appear to help discriminate not only between regions but also specific sites. In addition, we completed a pilot study of archaeological wood samples obtained in Greenland to test the effectiveness of the ⁸⁷Sr/⁸⁶Sr biogeochemical baseline. Results demonstrate that at least in some cases, diagenetic processes were not sufficient to mask a non-local ⁸⁷Sr/⁸⁶Sr signature.