Geochemical features and genesis of continental cobalt-rich ferromanganese crusts

Abstract

Mass cobalt-rich ferromanganese microcrusts and nodules similar in morphology and chemical composition to cobalt-rich ferromanganese deep-ocean crusts were found in Cenozoic volcanic rocks in southern Primorye. Research has shown that ore genesis of this type is genetically related to argillization and destruction of siliceous rocks by CO2-rich fluids, which is confirmed by experimental data on carbon erosion of iron-containing materials. Two types of this fluid ore genesis are recognized: (1) relatively high-temperature (vapor–condensate), related to late volcanic processes and fracture gas infiltration, and (2) low-temperature (vapor–liquid–condensate), controlled by degassing followed by carbon mobilization (gasification). Primarily colloidal ferromanganese segregations have high contents of Co, Ni, Pb, Cu, and Ce, typical of oceanic ore genesis. Regardless of the concentrations of these metals in the protoliths, their contents in microcrusts are similar (n–10n wt.%). This indicates the same ore genesis mechanism and similar sorption properties of the colloidal ferromanganese material formed. Barium- and cerium-rich ferromanganese microcrusts and nodules are abundant. Condensed drops of iron-containing platinum were found in apobasaltic nickel-rich ferromanganese segregations. There is a cerium paradox expressed as a minimum or a total lack of cerium among rare-earth phosphates associated with ferromanganese microcrusts. Fluid destruction and oxide metallization of ocean-floor basalts are assumed to be the main source of metals for oceanic ferromanganese crusts and nodules.

Recovery of Valuable Metals and NaCl from Cobalt-Rich Crust and Industrial Waste Salt via Roasting Coupling Technology

“…There are huge reserves of cobalt-rich crust resources in the ocean. The exploitation of cobalt-rich crust resources will be the long-term trend in the future with the decreasing of terrestrial mineral resources [4][5][6][7][8]. However, the key to the extraction of valuable metals such as manganese, cobalt, nickel, and copper from cobalt-rich crust is to destroy the original lattice of the ferro-manganese oxide minerals by a variety of means [9].…”