Geochemical record of the Panama basin during the last glacial maximum carbon event shows that the glacial ocean was not suboxic

A geochemical study of sediments associated with the last glacial maximum carbon event in the Panama Basin has shown that increased glacial productivity raised the redox boundary closer to the sediment-water interface, leading to increased storage of U and Mn in the sediments. However, it seems improbable that the basin became suboxic, and this would suggest that the Mn concentrations were not elevated in the glacial ocean. Fluxes of ²³⁰Th and ²³¹Pa were higher in glacial times in the Panama Basin sediments, probably as a consequence of the elevated productivity, but age-corrected ²³⁰Th/²³¹Pa ratios were higher. This is consistent with reports of higher particle fluxes external to the basin throughout the glacial Pacific Ocean.