Geochemical Characteristics of Iron in a Sediment Core at 63°40′ E, Eastern Southwest Indian Ridge: Implications on Regional Hydrothermal Activities and Source Origin

Iron is a limiting nutrient in the marine biogeochemical cycle, and hydrothermal processes at mid-ocean ridges are well-known as one of its sources to water column. However, major portion iron precipitated near source plays an essential role oceanic elemental cycling. Here, we carried out detailed study on geochemical characteristics Fe, using sequential chemical extraction protocol, short sediment core collected from eastern Southwest Indian Ridge (SWIR) understand association individual mineral phases. Major trace rare-earth element concentrations, positive europium anomaly, fractionation show that components composed biogenic, local mafic, ultramafic, origin. Solid-phase Fe speciation results indicate >60% associated with Fe-oxides phase plume particulates settled A relatively low concentration pyrite silicate (FeRes) suggests erosion sulphide minerals nearby vent field. The down-core variation reflects transformation primary ferrihydrite more stable oxide goethite/hematite and, some extent, formation minerals.