Chemical analyses by XRF Quantometer of south Penrhyn Basin manganese nodules

A CCOP/SOPAC cruise aboard C.I.G.M.F.V. Ravakai in June 1976 found a high density manganese nodule field in the south Penrhyn Basin between Aitu-taki and Penrhyn in the Cook Islands. Nodules were recovered at 9 of the 12 stations occupied, and underwater photographs taken at 6 of these 9 stations indicate about a 90% nodule coverage of the sea floor corresponding to a surface density of nodules in the range 15-30 kgm/nf2 . Stiff grayish brown (5 YR 3/2) abyssal clay was recovered at all stations. Selected manganese nodules from each station were analysed at the University of Hawaii by E. Okazaki using an XRF Quantometer. Analysis are expressed as element weight percent on a dry weight basis.