Supplementary Material
Indications for a hiatus in core GeoB 19905-1:
The carbonate contents of core GeoB19905-1 closely match the abundance of foraminifera as well Ca-counts from the XRF-scanning, hence the majority of carbonate in the sediment is biogenically produced calcite.
CaCO3-contents, foraminifera abundances and Ca-counts (presented here as the Ca/Fe ratio) show a
pronounced maximum between 780 and 480 cm core depth. Assuming an age-depth relation without an hiatus, the carbonate accumulation rate would drop conspicuously while the foraminifera abundance remains highest (see fig. S1). Consequently, to align the pattern of the biogenic carbonate contribution to the core with the interpreted stratigraphy and the resulting accumulation rates, a hiatus in the critical core section appears as the most probable solution.
Figure S 1: Top panel: BACON-plot for a default modelling run, assuming no hiatus (left) and BACON-plot of the final age model used in this study (right). Bottom panel shows carbonate and bulk accumulation rates next to the abundance of foraminifera in the sediment and the Ca/Fe-ratio resulting from XRF-scanning and the carbonate contents. On the left, the accumulation rates assuming no hiatus (in accordance to the age model shown directly above) are shown, on the right the accumulation rates resulting from the final age model are shown. Combined these plots illustrate the conspicuous effect of neglecting the hiatus at 640cm.
