A Study of the Growth Morphologies of Two Deep-Sea Manganese Meganodules

Abstract

The morphologies of manganese are numerous; commonly, they are classified as: micronodules, meganodules, crusts, botryoidals, and agglomerates. Within these classes are numerous shape categories. The purpose of this paper is to describe two, shape and surface-texture categories for manganese meganodules taken in a dredge (V16-SBT3) by Lamont-Doherty Geological Observatory near the Mid-Atlantic Ridge, at lat. 13°04' S, long. 24°41 ' W, in 4,700 meters water depth . Septarian concretionary features were observed on the bulk of the nodules, as were concentric manganese ring growths around rock centers, constituting the first known occurrence of this morphology in deep-sea sediments.