The U-series dating of young and 'dirty' speleothems is challenging due to difficulties in assessing the isotopic composition of detrital contaminants and the low-abundance of Th generated in situ. Here we propose a new dating approach based on the comparison of a speleothem's paleomagnetic directions to reference curves from global paleomagnetic reconstructions. This approach is demonstrated on a stalagmite collected from the Soprador do Carvalho cave in the Central Region of Portugal.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
February 2017
This study examines the geochemical and mineralogical variations in the ferruginous mineralisations that crop out within Grotta della Monaca, which is considered to be the most striking and best known example of a prehistoric iron mine-cave from the southern Apennines (Calabria, Italy). Previous archaeological research identified three local and distinct ancient exploitation phases of these ferruginous mineralisations: (1) an Upper Palaeolithic phase; (2) a Late Neolithic phase; and (3) a post-Medieval phase. These materials, which have various forms of complex mineralogical admixtures and range in colour from yellow-orange to red and darker brown shades, mainly consist of iron oxides/hydroxides (essentially goethite and lepidocrocite), which are often mixed with subordinate and variable amounts of other matrix components (carbonates, sulphates, arsenates, silicates and organic matter).
View Article and Find Full Text PDFThis paper presents a geoarchaeological study of Middle and Upper Palaeolithic (Châtelperronian, Aurignacian and Solutrean) occupations preserved at the Bordes-Fitte rockshelter in Central France. The lithostratigraphic sequence is composed of near-surface sedimentary facies with vertical and lateral variations, in a context dominated by run-off and gravitational sedimentary processes. Field description and micromorphological analysis permit us to reconstruct several episodes of sediment slope-wash and endokarst dynamics, with hiatuses and erosional phases.
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