Geochemistry of a hydrothermal sediment core from the OBS vent-field, 21 degrees N East Pacific Rise

Abstract

We report a geochemical investigation of near-vent hydrothermal sediment from the East Pacific Rise, collected in a short (11 cm) core by submersible from the OBS vent-site at 21°N. The sediment has high concentrations of Fe (23-25%), Cu (10-22%), Zn (4-13%) and S (22-30%), but low Mn concentrations (108-279 ppm) indicating a much fresher sulfidic input than in previously reported near-vent sediments from the Mid-Atlantic Ridge. Further studies are required to fully characterise near-field hydrothermal sediments, but the data in this study allow the first comparisons with similar near-vent material collected previously from the Mid-Atlantic Ridge as well as ridge-flank data from the EPR and ..