Fig. 2.

Oceanographic profiles showing a hydrothermal influence on dFe, ³He, and dMn at 2,000 m. Relevant profiles taken from (A) SPEEDO-KM0703 Station 19 in the southwest Pacific, (B) Melville BiG RAPA Station 7 in the southeast Pacific, and (C) Melville BiG RAPA Station 4 in the southeast Pacific. Note that dFe SDs on replicate analyses (tabulated in Table S1) were typically the size of the symbol and are thus not shown. The interpolated excess ³He data are shown as blue circles at the depths where dFe measurements were made, whereas the data used to generate those average values are shown as light blue crosses.