Chemotrophic microorganisms gain energy for cellular functions by catalyzing oxidation–reduction (redox) reactions that are out of equilibrium. Calculations of the Gibbs energy (
The degassing of CO2and S from arc volcanoes is fundamentally important to global climate, eruption forecasting, ore deposits, and the cycling of volatiles through subduction zones. However, all existing thermodynamic/empirical models have difficulties reproducing CO2‐H2O‐S trends observed in melt inclusions and provide widely conflicting results regarding the relationships between pressure and CO2/SO2in the vapor. In this study, we develop an open‐source degassing model, Sulfur_X, to track the evolution of S, CO2, H2O, and redox states in melt and vapor in ascending mafic‐intermediate magma. Sulfur_X describes sulfur degassing by parameterizing experimentally derived sulfur partition coefficients for two equilibria: RxnI. FeS (
- PAR ID:
- 10404965
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geochemistry, Geophysics, Geosystems
- Volume:
- 24
- Issue:
- 4
- ISSN:
- 1525-2027
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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