| 1. |
- Plymale, Andrew E., et al.
(författare)
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Niche Partitioning of Microbial Communities at an Ancient Vitrified Hillfort : Implications for Vitrified Radioactive Waste Disposal
- 2021
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Ingår i: Geomicrobiology Journal. - : Taylor & Francis. - 0149-0451 .- 1521-0529. ; 38:1, s. 36-56
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Tidskriftsartikel (refereegranskat)abstract
- Because microbes cannot be eliminated from radioactive waste disposal facilities, the consequences of bio-colonization must be understood. At a pre-Viking era vitrified hillfort, Broborg, Sweden, anthropogenic glass has been subjected to bio-colonization for over 1,500 years. Broborg is used as a habitat analogue for disposed radioactive waste glass to inform how microbial processes might influence long-term glass durability. Electron microscopy and DNA sequencing of surficial material from the Broborg vitrified wall, adjacent soil, and general topsoil show that the ancient glass supports a niche microbial community of bacteria, fungi, and protists potentially involved in glass alteration. Communities associated with the vitrified wall are distinct and less diverse than soil communities. The vitrified niche of the wall and adjacent soil are dominated by lichens, lichen-associated microbes, and other epilithic, endolithic, and epigeic organisms. These organisms exhibit potential bio-corrosive properties, including silicate dissolution, extraction of essential elements, and secretion of geochemically reactive organic acids, that could be detrimental to glass durability. However, long-term biofilms can also possess a homeostatic function that could limit glass alteration. This study documents potential impacts that microbial colonization and niche partitioning can have on glass alteration, and subsequent release of radionuclides from a disposal facility for vitrified radioactive waste.
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| 2. |
- Matthews, Bethany E., et al.
(författare)
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Micro- and Nanoscale Surface Analysis of Late Iron Age Glass from Broborg, a Vitrified Swedish Hillfort
- 2023
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Ingår i: Microscopy and Microanalysis. - : Oxford University Press. - 1431-9276 .- 1435-8115. ; 29:1, s. 50-68
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Tidskriftsartikel (refereegranskat)abstract
- Archaeological glasses with prolonged exposure to biogeochemical processes in the environment can be used to understand glass alteration, which is important for the safe disposal of vitrified nuclear waste. Samples of mafic and felsic glasses with different chemistries, formed from melting amphibolitic and granitoid rocks, were obtained from Broborg, a Swedish Iron Age hillfort. Glasses were excavated from the top of the hillfort wall and from the wall interior. A detailed microscopic, spectroscopic, and diffraction study of surficial textures and chemistries were conducted on these glasses. Felsic glass chemistry was uniform, with a smooth surface showing limited chemical alteration (<150 nm), irrespective of the position in the wall. Mafic glass was heterogeneous, with pyroxene, spinel, feldspar, and quartz crystals in the glassy matrix. Mafic glass surfaces in contact with topsoil were rougher than those within the wall and had carbon-rich material consistent with microbial colonization. Limited evidence for chemical or physical alteration of mafic glass was found; the thin melt film that coated all exposed surfaces remained intact, despite exposure to hydraulically unsaturated conditions, topsoil, and associated microbiome for over 1,500 years. This supports the assumption that aluminosilicate nuclear waste glasses will have a high chemical durability in near-surface disposal facilities.
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| 3. |
- Ling, Johan, 1968, et al.
(författare)
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Moving metals II: Provenancing Scandinavian Bronze Age artefacts by lead isotope and elemental analyses
- 2014
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Ingår i: Journal of Archaeological Science. - : Elsevier BV. - 0305-4403 .- 1095-9238. ; 41, s. 106-132
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Tidskriftsartikel (refereegranskat)abstract
- The first part of this research published previously proved without doubt that the metals dated to the Nordic Bronze Age found in Sweden were not smelted from the local copper ores. In this second part we present a detailed interpretation of these analytical data with the aim to identify the ore sources from which these metals originated. The interpretation of lead isotope and chemical data of 71 Swedish Bronze Age metals is based on the direct comparisons between the lead isotope data and geochemistry of ore deposits that are known to have produced copper in the Bronze Age. The presented interpretations of chemical and lead isotope analyses of Swedish metals dated to the Nordic Bronze Age are surprising and bring some information not known from previous work. Apart from a steady supply of copper from the Alpine ores in the North Tyrol, the main sources of copper seem to be ores from the Iberian Peninsula and Sardinia. Thus from the results presented here a new complex picture emerges of possible connectivities and flows in the Bronze Age between Scandinavia and Europe. © 2013 Elsevier Ltd.
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| 4. |
- Ling, Johan, 1968, et al.
(författare)
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Moving metals V: The question of shared copper sources between Scandinavia and Hungary 1700-1500 BC
- 2023
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Ingår i: Journal of Archaeological Science-Reports. - 2352-409X. ; 51
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Tidskriftsartikel (refereegranskat)abstract
- The remarkable typological parallels between Carpathian and Scandinavian metalwork, especially from around 1700 to 1500 BC, have long been stressed as evidence that the Carpathian tell communities supplied the Scandinavians with copper. Thus, this study's main objective was to investigate if Bronze Age societies in Scandinavia and the Carpathian basin utilized the same copper sources. To test this hypothesis, analyses, comprising lead isotopes and trace elements, were executed on bronzes from Scandinavia and Hungary. In the current study, the Hungarian data set of 31 artefacts from the famous Szazhalombatta hoard and its nearby settlement, is in detail compared to 62 Scandinavian artefacts of various types. The outcome points to that Scandinavia and Hungary partly shared copper sources between 1700 and 1500 BC. The most potential sources are the ones from the Slovak Ore Mountains and Mitterberg in Austria. However, the Scandinavian artefacts from this period also show consistency with additional copper sources, such as Great Orme in Wales and in the Italian Alps. The findings of this study support both the traditional theory, which stated that metal supplies and metalworking traditions were closely related, and the more recent insight, which suggests that style and content may have entirely separate origins. As a result, the intricacy of the production, exchange, and consumption patterns of metal throughout Bronze Age Europe cannot be explained by a simple model that equates stylistic influence and metal suppliers.
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| 5. |
- Melheim, L., et al.
(författare)
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Moving metals III: Possible origins for copper in Bronze Age Denmark based on lead isotopes and geochemistry
- 2018
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Ingår i: Journal of Archaeological Science. - : Elsevier BV. - 0305-4403 .- 1095-9238. ; 96, s. 85-105
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Tidskriftsartikel (refereegranskat)abstract
- © 2018 Elsevier Ltd This article presents the results of a comprehensive provenance study based on a combined geochemical-isotopic and archaeological approach, comprising 98 analyses of 97 copper-alloy objects from the Danish Bronze Age. When it comes to the question of the origin of the metal, our interpretations diverge somewhat from earlier established theories about the origin of copper imported to Denmark, which mainly pointed to Central and Eastern Europe. Clear geochronological patterns in the Danish dataset are interpreted as being due to shifts in ore sources; reflecting varying areas of origin as well as the utilization of varying ore types. This again relates to shifting trade networks/suppliers and shifting technological trends. Plausible sources for Danish copper-alloys identified in the current study are ore regions in the British Isles, Alpine ore districts in Italy and Austria, as well as ore regions in the western part of the Mediterranean and to some degree the Slovak Carpathians. The comparison includes hundreds of recently published lead isotope data for ores in Slovakia, the Iberian Peninsula and the Italian and Austrian Alps.
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