Chemical element contents and speciations in bottom sediments from the Transpacific profile

With increasing distance from the shore and with transition from reduced coastal sediments to oxidized deep-sea red clays concentration of iron and manganese in the interstitial waters greatly decreases.

Elevated concentration of dissolved iron (0.34 mg/l) was observed only in highly reduced terrigenous sediments from the shelf and continental slope of Mexico. The highest concentrations of manganese (13.2 mg/l) were measured in hemipelagic carbonate-siliceous-clayey sediments. Compared to Pacific seawater interstitial waters are enriched in Fe, Mn, Cu, Ni, V. Interstitial waters contain only from 0.000004 to 1.2% of total contents of these elements in bottom sediments.