Circumpolar deep water upwelling is a primary source of 10Be in Antarctic continental shelf sediments

Beryllium-10 (10Be) is proposed to be a potential proxy for investigating ice shelf presence and absence, or meltwater discharge in coastal polar environments. However, the sources and distribution of atmospherically produced meteoric-10Be in the Antarctic marine realm are yet to be fully characterized. We present a dataset of 9Be and 10Be concentrations, and 10Be/9Be ratios in seafloor surface sediments from the Antarctic continental shelf to assess the sources and processes contributing Be-isotopes to ice-sheet proximal marine settings. We show that upwelling waters (e.g. Circumpolar Deep Water) are a significant source of 10Be to continental shelf sediments. This limits the use of 10Be/9Be as a proxy for ice shelf environment or meltwater discharge, but instead provides a potential proxy for reconstructing Circumpolar Deep Water incursions onto Antarctic continental shelves.

Details