Marine Geochemistry 1. Chemical Scavengers of the Sea

TLDR

Hydrated manganese and iron oxides in marine sediments adsorb ions, producing linear relationships among iron, titanium, cobalt, zirconium, manganese, copper, and nickel, and shaping the distribution of ionic species and minor element concentrations via scavenging and coordination compound theory. The study presents an electrochemical theory for the formation of manganese nodules. The authors develop an electrochemical model to explain manganese nodule formation.

Abstract

The ability of the hydrated oxides of manganese and iron to adsorb ions from solution (scavenging) is considered in relation to some problems in marine geology, chemistry, and biology. In the ferruginous sediments of the Pacific Ocean, iron oxides are accompanied by titanium, cobalt, and zirconium in amounts proportional to the iron content. Similarly, copper and nickel are linearly related to the manganese content. These observations are explained on the basis of scavenging. An electrochemical theory for the formation of manganese nodules is presented. Marine sediments are classified on the basis of the geosphere in which the solid phases originate. The distribution of certain ionic species in sea water between the solid and aqueous phases is considered on the basis of scavenging and co-ordination compound theory. The concentration of minor elements by members of the marine biosphere is explained either by the direct uptake of the element or by the uptake of iron or manganese oxides with the accompanying scavenged element.