Rates of Accumulation of Ferro-manganese Nodules

Abstract

ALTHOUGH various models have been proposed to explain the origin of manganese nodules (see Goldberg and Arrhenius¹), two major hypotheses have received extensive attention. One concept suggests that manganese nodules form as the result of interaction between submarine volcanic products and sea water^2,3. 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 Arrhenius¹ 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 Nayudu³ believe manganese nodule formation takes place subsequent to the eruption of submarine volcanoes by the acidic leaching of lava.