Abstract: | Determinations of the nickel, manganese and iron present in sediment cores from the Central Pacific Ocean have been made by microchemical methods. The results show (a) that the nickel content is high relative to that of continental rocks and sediments and, (b) that there are considerable variations in the nickel contents with depth below the sediment surface. No correlation with the manganese and iron contents is evident except in cases where a change in the rate of sedimentation appears to have affected all three elements in the same manner. |