The biogeochemical cycle of barium in the open ocean: an evaluation

This study constitutes our contribution to the international oceanographical GEOSECS program (Geochemical Ocean Sections). The Ba content of suspended particulate matter was studied by neutron activation analysis. Analysis with the electron microscope and electron microprobe equipment have allowed the identification of the mineral barite as the main carrier of Ba in oceanic suspensions. Strong evidence is offered for a biological formation of these baryte monocrystals. An estimation of the amount of Ba introduced into the deep ocean by dissolution of the barite crystals was possible. Finally, our results enabled a modelling of the general biogeochemical cycle of Ba in the ocean