Behavior of Trace Elements during Oxidation of Sphalerite of the Irinovskoe Hydrothermal Sulfide Field (13°20′ N, Mid-Atlantic Ridge)

Abstract

The formation of present-day seafloor sulfide deposits is accompanied by their continuous oxidation and crystallization of insoluble Fe oxyhydroxides, which absorb metals (including heavy metals) (Fallon et al., 2017). Due to the high sorption ability of Fe oxyhydroxides, it is suggested that the removal of metals during submarine oxidation into ambient seawater is insignificant (Fallon et al., 2017). Quantitative data on the redistribution of trace elements between primary sulfides and their oxidation products, however, are insufficient. Recently, we revealed the enrichment of trace elements in covellite with respect to primary sphalerite, chalcopyrite, and isocubanite (Melekestseva et al., 2017). In this study, we estimate the behavior of trace elements during submarine oxidation of sphalerite from smokers at the Irinovskoe hydrothermal field (Atlantic Ocean), which is intensely replaced by Fe oxyhydroxides. As a result, it is established that Fe oxyhydroxides are enriched in many trace elements with respect to sphalerite and the mode of their occurrence is identified.