Potassium and Argon data for dating the core, and radiochemical data of a series of measurements made on layers inside various manganese nodules from the Pacific Ocean

One concept suggests that manganese nodules form as the result of interaction between submarine volcanic products and sea water. The common association of manganese nodules with volcanic materials constitutes the main evidence for this theory.

The second theory involves a direct inorganic precipitation of manganese from sea water. Goldberg and Arrhenius view this process as the oxidation of divalent manganese to tetravalent manganese by oxygen under the catalytic action of particulate iron hydroxides. Manganese accumulation by the Goldberg and Arrhenius theory would be a relatively slow and comparatively steady process, whereas Bonatti and Nayudu believe manganese nodule formation takes place subsequent to the eruption of submarine volcanoes by the acidic leaching of lava.