The distribution of rubidium, cesium and barium in the oceans

Rubidium, cesium and barium have been determined in several oceanic profiles by a neutron activation procedure based on the extraction of salt from 100 ml. samples by freeze-drying. Assuming a constant strontium-chlorinity ratio of 0.0425, strontium was used as an internal flux monitor. For 19.0% chlorinity the average concentrations of these three elements are 125 μg Rb/1. (10 samples), 0.30 μg Cs/1. (28 samples), and 13 μg Ba/1. (6 samples) with very little variation with depth or geographic location. Rubidium and cesium apparently are not efficiently transported to great depths by organisms, and cesium at least is not in exchange equilibrium with deep-sea clays. The barium data are for six stations only, mainly from areas of low productivity and low barium concentrations in associated deep-sea sediments. High oceanic barium values might be expected in areas of high productivity and associated high barium in deep-sea sediments.