Particle fluxes, mineralogy, and chemistry of sedimentary material in the broken spur hydrothermal field, Mid-Atlantic Ridge, 29 degrees N

The particle flux near the Saracen's Head "black smoker," Broken Spur hydro thermal field, was determined using a sediment trap. We studied the mineral ogical and chemical composition of the material. The ore minerals are Fe su lfides (pyrite and pyrrhotite), and Zn and Cu sulfides, which occur in equa lly low amounts. Ca minerals (anhydrite, gypsum, and calcite) are the major gangue minerals. The sediment traps within and below the hydrothermal plum e collected mainly biogenic material with an admixture of hydrothermal comp onents. This material is enriched in Fe, Zn, Ca, Si, Ba, and P relative to the background concentrations.