Planetary surfaces

Abstract:

Heterogeneous electrochemistry induced by Martian dust activity is an important type of atmosphere-surface interaction that affects geochemical processes at the Martian surface and in the Martian atmosphere. We have experimentally demonstrated that heterogeneous electrochemistry stimulated by mid-strength dust events can decompose common chloride salts, which is accompanied by the release of chlorine atoms into the atmosphere and the generation of (per)chlorates (chlorates and perchlorates) and carbonates. In this study, we present quantitative analyses on the above products from 26 heterogeneous electrochemical experiments on chloride salts. Based on these quantifications, our calculation indicates that such atmosphere-surface interaction during a portion of Amazonian period could accumulate the observed abundance of (per)chlorates, carbonates, and HCl by landed and orbital missions, and thus can be considered as a major driving force of the global chlorine-cycle on Mars. This study emphasizes the importance of measuring the electrical properties of dust activity on Mars.