Utilization of δ 13 C, δ 15 N, and δ 34 S Analyses to Understand 14 C Dating Anomalies within a Late Viking Age Community in Northeast Iceland

• Published in: Radiocarbon
• Main Authors: Sayle, Kerry L, Cook, Gordon T, Ascough, Philippa L, Gestsdóttir, Hildur, Hamilton, W Derek, McGovern, Thomas H
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 2014
• Subjects: Mývatn; Iceland
• Online Access: http://dx.doi.org/10.2458/56.17770; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0033822200049845

Previous stable isotope studies of modern and archaeological faunal samples from sites around Lake Mývatn, within the Mývatnssveit region of northeast Iceland, revealed that an overlap existed between the δ 15 N ranges of terrestrial herbivores and freshwater fish, while freshwater biota displayed δ 13 C values that were comparable with marine resources. Therefore, within this specific ecosystem, the separation of terrestrial herbivores, freshwater fish, and marine fish as components of human diet is complicated when only δ 13 C and δ 15 N are measured. δ 34 S measurements carried out within a previous study on animal bones from Skútustaoir, an early Viking age settlement on the south side of Lake Mývatn, showed that a clear offset existed between animals deriving their dietary resources from terrestrial, freshwater, and marine reservoirs. The present study focuses on δ 13 C, δ 15 N, and δ 34 S analyses and radiocarbon dating of human bone collagen from remains excavated from a churchyard at Hofstaoir, 5 km west of Lake Mývatn. The results demonstrate that a wide range of δ 34 S values exist within individuals, a pattern that must be the result of consumption of varying proportions of terrestrial-, freshwater-, and marine-based resources. For that proportion of the population with 14 C ages that apparently predate the well-established first human settlement of Iceland ( landnám ) circa AD 871 ± 2, this has enabled us to explain the reason for these anomalously old ages in terms of marine and/or freshwater 14 C reservoir effects.