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Pelagic carbonate sections constitute common archives for paleoclimatological and stratigraphical research. This study evaluates the use of portable X-ray fluorescence (pXRF) measurements on pelagic carbonates and applies the method to the well-studied latest Maastrichtian in the Bottaccione Gorge section from Gubbio, Italy. A calibration with carbonate reference materials makes it possible to acquire absolute elemental concentrations, and allows for comparison with results from previous geochemical studies, which used more expensive and time consuming conventional techniques, such as neutron activation or Inductively Coupled Plasma Mass Spectrometry (ICP-MS). With adequate measurement strategies and careful calibration, pXRF measurements can be a reliable, non-destructive, cheap, fast and easy to use alternative to acquire multi-elemental concentration data (Ca, Fe, Mn, Sr) in pelagic carbonates. These pXRF elemental concentration data represent valuable additions to classical proxies such as magnetic susceptibility and calcium carbonate content used in the study of pelagic carbonates. Furthermore, the potential of the portable pXRF method for applications in cyclostratigraphical (e.g. using Fe-concentrations) and chemostratigraphical (e.g. using Mn and Sr concentrations) investigations is demonstrated. A strong covariation between the measured Sr concentration profile obtained by pXRF and the existing δ18O record, in combination with micro-XRF mapping, demonstrated the sampling of calcite veins in some of the samples. The first 87Sr/86Sr isotope measurements for the latest Maastrichtian in the Bottaccione Gorge section seem to be little affected by this sampling effect.

info:eu-repo/semantics/published

Burned human bones are commonly found in archaeological contexts. Due to high temperature during burning (up to 1000°C), organic components of bone disappear and significant structural, chemical and isotopic changes to the inorganic fraction of bone (bone apatite) take place. Despite these limitations, burned bones play an increasingly important role in our understanding of societies in which cremation was the dominant funerary practice. For this reason, the application of new micro- and macroscopic techniques to archaeological cremated bone collections enables new inferences on pyre technology, pyre management and specialisation concerning the use of fire in funerary rituals. The aim of this project is to investigate inter- and intra- site differences in burning conditions (temperature of the fire, duration, size of the pyre, amount and quality of the fuel, position of the body, fire extinguishing), pre and post cremation treatment of body at several Belgian Late Bronze Age, Iron Age and Roman sites. In addition to osteological analysis, carbon, oxygen and strontium isotope analysis, infrared spectroscopy (FTIR), X-Ray diffraction (XRD) and elemental analysis (ICP-MS) were conducted in order to extract information from the burned bones. The results of infrared spectroscopy and carbon and oxygen isotope analysis of different skeletal elements (diaphysis, cranial bones, ribs) from different sites indicate that both the temperature and the position of the body on the pyre vary between different sites and time periods. This variability adds to our understanding regarding the specialisation of pyre technology and management at the studied sites. Inter- and intra- site variability in the burning process will be examined in the light of these results, as well as their archaeological context.