The strontium isotope composition of human tissues is widely used in archaeological mobility studies. However, little attention is paid to the relative contributions of terrestrial versus marine sources of strontium in these studies. There is some debate over the role of a solid diet versus drinking water as the most important source of strontium for the human body, with related possibilities of misinterpretation of the archaeological record if only strontium isotope compositions of the biosphere are studied. However, there is a third component, marine strontium, which is commonly not assumed to contribute towards the strontium isotope composition of archaeological skeletal remains, especially in locations that are not directly coastal. To illustrate the potentially obfuscating effects of mixed Sr sources in a human population, we present a case study of twelve individuals from the medieval Finnish site Iin Hamina with a known dietary history. Our study shows that marine consumption is a significant factor explaining the strontium isotope composition of the Iin Hamina human remains, with implication of erroneous conclusions about immigration without prior knowledge of diet composition. Thus, future studies should always incorporate a rigorous analysis of dietary history, with special regard to potential consumption of aquatic resources, when strontium isotope analysis is used as a method in the study of palaeomobility.

人体组织中锶同位素的组成被广泛用于考古活动研究中。但是，在这些研究中，很少关注陆地和海洋锶的相对贡献。关于固体饮食与饮用水作为人体最重要的锶来源的作用存在一些争论，如果仅研究生物圈中的锶同位素组成，则可能会误解考古记录。但是，还有第三种成分，海洋锶，通常不认为它对考古骨骼遗骸的锶同位素组成有贡献，特别是在不直接沿海的地区。为了说明混合锶源对人类的潜在混淆作用，我们提供了一个来自中世纪芬兰遗址Iin Hamina的十二个人的案例研究，这些饮食具有已知的饮食史。我们的研究表明，海洋消费是解释Iin Hamina人体残骸中锶同位素组成的重要因素，可能暗示在没有饮食成分事先知识的情况下关于移民的错误结论。因此，当锶同位素分析被用作古生物研究方法时，未来的研究应始终对饮食史进行严格的分析，特别要注意潜在的水生资源消耗。在没有饮食成分事先知识的情况下得出有关移民的错误结论。因此，当锶同位素分析被用作古生物研究方法时，未来的研究应始终对饮食史进行严格的分析，特别要注意潜在的水生资源消耗。在没有饮食成分事先知识的情况下得出有关移民的错误结论。因此，当锶同位素分析被用作古生物研究方法时，未来的研究应始终对饮食史进行严格的分析，特别要注意潜在的水生资源消耗。