Crystalline todorokite associated with biogenic debris in manganese nodules.

Platy intergrowths of crystalline todorokite are associated with biogenic debris in the cores of manganese nodules from a site in the Pacific Ocean. Analyses by electron diffraction and transmission electron microscopy demonstrate that this material is composed of tunnels of chains of linked MnO(6) octahedra. The chemical composition, morphology, and stability of the todorokite differ from those of nickel-and copper-rich manganese oxides in nodules that have been identified as todorokite or buserite in earlier investigations.