Program > Browse abstracts by speaker > Erftemeijer Rody

The surface of Mercury is enriched in sulfur, with concentrations of up to 4 wt.%. One of the theories to explain this enrichment is that the sulfur originates from the interior of the planet, being released during volcanic degassing and subsequently reacting with surface material to form sulfides. As the behavior of sulfur under Mercury's highly reducing conditions is unclear, this study aims to get a better handle on the kinetics and mineralogy of the reactions between gaseous sulfur and silicate minerals representing Mercury's surface.

The experiments for this study were performed in evacuated silica glass tubes. First, sulfur powder and a polished silicate mineral – olivine, diopside, or albite – were loaded in separate graphite capsules, which were subsequently mounted inside a silica glass tube. After sealing the glass tube under vacuum, experiments were performed inside a high-temperature furnace at temperatures between 800 and 1200 °C. Under these conditions, the sulfur powder forms a gas and fills the ampule, allowing it to react with the silicate mineral. The run duration of the experiments was varied from one hour to one week. Moreover, the oxygen fugacity inside the glass tube was buffered by the graphite-CO reaction, which represents Mercury's highly reducing conditions. Hence, this technique serves as an ideal analog for the surface of Mercury.