| 摘 要： | Manganese nodules collected from the North Penrhyn Basin are characterized by low content of Mn and Fe, medium content of Ni and Cu , and medium Mn / Fe ratios . The average content of Ni plus Co is 1.11% , maximum 1.89% . Ni content slightly exceeds the Cu content in the nodules. Ni and Cu are strongly correlated with Mn , whereas Co is strongly correlated with Fe . Nodules containing Ni+Cu+Co near or in excess of 1% are rich in Mn and have a high Mn/Fe ratio. Those with highest content of Ni+Cu+Co are concentrated at or near the carbonate compensation depth . Nodules metal contents vary with latitude and have a reciprocal relationship with abundance. Contents of Mn, Ni, Cu and Ni+Cu+Co are high in nodules found at 2 - 6°S and vary decreasingly toward 1°N and 12°S , whereas Co content varies increasingly from 2°S towards 12°S. Nodule compositional variations with latitude are controlled by biological productivity, carbonate compensation depth , sedimentation rate, and bottom current.
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