Journal
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
Volume 110, Issue 20, Pages 8010-8013Publisher
NATL ACAD SCIENCES
DOI: 10.1073/pnas.1219266110
Keywords
hydrogen; iron carbonyl; magmatic volatiles; experimental petrology
Categories
Funding
- National Aeronautics and Space Administration LASER Grants [NNX08AY97G, NNX11AB27G]
- US National Science Foundation [EAR-0748707]
- David and Lucile Packard Foundation
- Deep Carbon Observatory
- NASA [92657, NNX11AB27G, 150044, NNX08AY97G] Funding Source: Federal RePORTER
- Division Of Earth Sciences
- Directorate For Geosciences [0748707] Funding Source: National Science Foundation
Ask authors/readers for more resources
Degassing of planetary interiors through surface volcanism plays an important role in the evolution of planetary bodies and atmospheres. On Earth, carbon dioxide and water are the primary volatile species in magmas. However, little is known about the speciation and degassing of carbon in magmas formed on other planets (i.e., Moon, Mars, Mercury), where the mantle oxidation state [oxygen fugacity (fO(2))] is different from that of the Earth. Using experiments on a lunar basalt composition, we confirm that carbon dissolves as carbonate at an fO(2) higher than -0.55 relative to the iron wustite oxygen buffer (IW-0.55), whereas at a lower fO(2), we discover that carbon is present mainly as iron pentacarbonyl and in smaller amounts as methane in the melt. The transition of carbon speciation in mantle-derived melts at fO(2) less than IW-0.55 is associated with a decrease in carbon solubility by a factor of 2. Thus, the fO(2) controls carbon speciation and solubility in mantle-derived melts even more than previous data indicate, and the degassing of reduced carbon from Fe-rich basalts on planetary bodies would produce methane-bearing, CO-rich early atmospheres with a strong greenhouse potential.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available