BIOGEOCHEMISTRY OF BOG IRON IN NEW JERSEY PINE BARRENS

Rivers and swamps of the southern New Jersey Coastal Plain contain sporadic but quantitatively important deposits of bog iron. This consists of unconsolidated to massive limonite impregnating sands and silts, the only X-ray identifiable Fe mineral being goethite. The chemistry and hydrology of river, swamp and ground waters suggest that Fe is supplied by lateral and vertical migration of corrosive, acidic ground waters up through Fe-rich sediments toward aerated surfaces. Here oxidation of Fe is catalyzed by Fe-fixing bacteria including Thiobacillus ferrooxidans, Leptothrix ochracea, Crenothrix polyspora, Siderocapsa geminata, and Metallogenium sp. These bacteria are essential to the precipitation of Fe, which would not otherwise oxidize at significant rates given the acid pH and chemical composition of surface waters. © 1979.