Geochemical Features of Multi-Metallic Crust in the Middle Pacific Ocean

Multi-metallic crust from seamount is one kind of oceanic mineral resources with the most perspective exploitation. More than forty samples of the multi-metallic crust from six seamounts in the middle Pacific Ocean were analyzed by X-ray fluorescence and ICP-AES. Combining with the published data, the constituent variety and the elemental relationships are discussed under the consideration of the depth and topography of the crust derivation. The results show that the contents of the main ore-forming constituents in the samples from the middle Pacific Ocean are similar to those from the northwest Pacific Ocean and from Magellan, and that are slightly higher than those from Marshall. Obviously positive correlations between Ca and P, as well as Al and K, but negative correlation between Mn and Al, are found in the samples from the middle Pacific Ocean. Higher Co (0.63%), Fe (16.9%) and REEs, but lower Cu (0.11%) and Mn (21.3%) are also found in the middle Pacific Ocean than in the deep-sea multi-metallic nodules. The facts imply that the ore-forming environment of the crust and the nodule is different.