Applying and evaluating the use of portable X-ray fluorescence (pXRF) measurements on pelagic carbonates: Maastrichtian strata from the Bottaccione Gorge, Gubbio, Italy.

Portable X-ray fluorescence (pXRF) devices are increasingly used for acquiring elemental data for multi-proxy studies. Pelagic carbonate sections are a commonly studied archive for paleoclimatological and stratigraphical research. Therefore this study applies and evaluates the use of pXRF measurements on pelagic carbonates from the well-studied terminal Maastrichtian in the Bottaccione Gorge section from Gubbio, Italy. A calibration with carbonate reference materials is set up to acquire absolute elemental concentrations, and allows for comparison with previous geochemical studies. Furthermore the potential for cyclostratigraphical (Fe) and chemostratigraphical (Mn and Sr) applications is demonstrated. Moreover, we indicate a diagenetic imprint on at least the bulk δ18O, Sr-concentrations and Sr-isotope signals of this section. Overall, it can be concluded that with proper measurement strategies and careful calibration, pXRF measurements can be a reliable, relatively easy, non-destructive, less expensive, and relatively fast method to acquire multi-elemental concentration data (Ca, Fe, Mn, Sr). These data are valuable additions to classical proxies as magnetic susceptibility and calcium carbonate content to multi-proxy studies of pelagic carbonates.