Abiotic Methane Formation by Electrochemical Reactions under Simulated Martian Dust Conditions

While CH₄ is often considered to be a potential sign of biological or geological activity, the origin and variability of reported Martian CH₄ remain unresolved. Dust activity, a fundamental feature of the Martian climate, brings together atmospheric carbon dioxide (CO₂), water preserved in hydrous surface minerals, and strong electrochemical effects associated with electrostatic discharge (ESD), thereby creating favorable conditions for the generation of CH₄.

Here, we show that low-pressure CO₂ discharge in the presence of hydrated minerals can produce detectable CH₄ under controlled laboratory conditions, supporting a potential abiotic CH₄ formation pathway associated with dust activity. The CH₄ response is strongly mineral-dependent and is generally enhanced by greater availability of accessible mineral-associated water, while externally supplied water alone is insufficient to induce CH₄ formation in all mineral systems.