Manganese complexes oxyanions

Ferromanganese nodules and seamount crusts are characterized by distinct alternating layers of iron oxides and manganese oxides in addition to other components such as aluminosilicates (shale), CFA, and sometimes biogenic barite and carbonates in seamount crusts. Iron-oxide phases are enriched in elements that exist in normal seawater mainly as hydroxyl and carbonate complexes of tri- to pentavalent cations (e.g.. As, B, Bi, In, Ir, Rh, REEs, Y, Ti, Th, U, Zr, Hf, Nb, and Ta), oxyanions (e.g., P, Re, Ru, Os, S, Se, Te, V, and W), and divalent cations... 

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