Patterns in diversity : Geochemical analyses and settlement changes during the Iron Age - Early Medieval time in the Lake Mälaren region, Sweden

Sammanfattning: The principal aims of this thesis were two-fold, encompassing both a geochemical approach and a focus on the settlement structure of the Lake Mälaren region of Sweden during the first millennium A.D. Although the two approaches were linked by their common final purpose, to gain a better understanding of the Iron Age – Early Medieval society of the region, the implications of the geochemical results are not limited to any particular area or period in time. Settlement is analysed on three levels: 1) the house, through typological changes, 2) the house and farm, through the identification of space-use areas and activities by means of geochemical analysis, and 3) farms and hamlets in the landscape, by studying settlement patterns. The material is derived partly from the author’s own excavations and partly from contract excavations.The importance of the excavation method and sampling strategy for the end-results of the analyses is discussed and emphasized. Lipid analysis by gas chromatography-mass spectrometry (GC-MS) and element analysis by atomic absorption spectrophotometer (AAS) made it possible to fill the void between archaeological features with meaningful information regarding space use, and it was also possible to identify the use of certain features with previously unknown function through lipid analysis. Space-use areas by reference to a modern context featuring well-known activities were identified with element analyses, while lipid analysis enabled these space-use areas to be connected with the actual activities. In archaeological contexts where lipid degradation has proceeded further such identification becomes more difficult and useful compound ratios and biomarkers for archaeological issues have been examined. The results of geochemical analyses and lipid analyses performed on ceramics made it possible to discuss the functions and meanings of houses in more detail and to consider different types of house foundations and categories of buildings in a wider context.