The relationship between P/Fe and V/Fe ratios in hydrothermal precipitates and dissolved phosphate in seawater

A strong positive relationship between the molar P/Fe ratio in fresh hydrothermal Fe ferrihydrite precipitates and seawater‐dissolved phosphate has been demonstrated using samples from the Atlantic and Pacific Oceans. We ascribe this relationship to scavenging of dissolved phosphate from seawater during the formation of hydrothermal Fe‐rich particles above hydrothermal vents. In contrast, molar V/Fe ratios in hydrothermal particles are inversely correlated with dissolved phosphate. These results indicate that inter‐ocean variations in dissolved phosphate control the P/Fe and V/Fe ratios in hydrothermal Fe precipitates, one of the precursors of metalliferous sediment.