Chemical analysis of manganese nodules and crusts from the Romanche trench area (Atlantic ocean)

Manganese nodules and manganese crusts covering basalt or volcanic breccia rocks have been analysed using various methods. Energy dispersive X-Ray analysis (EDAX)was used for the determination of Fe, Mn, Ti, Mg, Al, Si, K, Ca, S. Measurements have been performed on pellets built from the samples reduced to powder. Results are presented as average of about 10 point measurements. Concentrations have been normalized at 100% of total metal oxides. Atomic absorption analysis was performed on the same samples for Ni, Cu, Co and Zn elements.