Carbonates identified by the Curiosity rover indicate a carbon cycle operated on ancient Mars
Ancient Mars had surface liquid water and a dense carbon dioxide (CO<sub>2</sub>)-rich atmosphere. Such an atmosphere would interact with crustal rocks, potentially leaving a mineralogical record of its presence. We analyzed the composition of an 89-meter stratigraphic section of Gale crater, Mars, using data collected by the Curiosity rover. An iron carbonate mineral, siderite, occurs in abundances of 4.8 to 10.5 weight %, colocated with highly water-soluble salts. We infer that the siderite formed in water-limited conditions, driven by water-rock reactions and evaporation. Comparison with orbital data indicates that similar strata (deposited globally) sequestered the equivalent of 2.6 to 36 millibar of atmospheric CO<sub>2</sub>. The presence of iron oxyhydroxides in these deposits indicates that a partially closed carbon cycle on ancient Mars returned some previously sequestered CO<sub>2</sub> to the atmosphere.
Authors
- E. B. Rampe (ORCID: https://orcid.org/0000-0002-6999-0028)
- David J. Des Marais (ORCID: https://orcid.org/0000-0002-6827-5831)
- A. A. Fraeman (ORCID: https://orcid.org/0000-0003-4017-5158)
- Valerie Tu (ORCID: https://orcid.org/0000-0003-1976-9058)
- T. Peretyazhko (ORCID: https://orcid.org/0000-0001-5533-6490)
- J. P. Grotzinger (ORCID: https://orcid.org/0000-0001-9324-1257)
- J. Frydenvang (ORCID: https://orcid.org/0000-0001-9294-1227)
- Steve Larter (ORCID: https://orcid.org/0000-0001-7195-1477)
- T. F. Bristow (ORCID: https://orcid.org/0000-0001-6725-0555)
- Amelie L. Roberts (ORCID: https://orcid.org/0000-0001-6504-3085)
- J. V. Clark (ORCID: https://orcid.org/0000-0003-2556-8586)
- P. J. Gasda (ORCID: https://orcid.org/0000-0003-0895-1153)
- J. C. Bridges (ORCID: https://orcid.org/0000-0002-9579-5779)
- B. Sutter (ORCID: https://orcid.org/0000-0002-3036-170X)
- A. H. Treiman (ORCID: https://orcid.org/0000-0002-8073-2839)
- Sarah Simpson (ORCID: https://orcid.org/0000-0003-3628-890X)
- D. F. Blake (ORCID: https://orcid.org/0000-0002-0834-4487)
- M. T. Thorpe (ORCID: https://orcid.org/0000-0002-1235-9016)
- Johannes M. Meusburger (ORCID: https://orcid.org/0000-0003-4367-3566)
- Elisabeth M. Hausrath (ORCID: https://orcid.org/0000-0002-5520-1622)
- H. B. Franz (ORCID: https://orcid.org/0000-0001-9716-5597)
- Edwin S. Kite (ORCID: https://orcid.org/0000-0002-1426-1186)
- Patricia Craig (ORCID: https://orcid.org/0000-0003-4080-4997)
- Aditi Pandey (ORCID: https://orcid.org/0000-0001-5869-1244)
- A. S. Yen (ORCID: https://orcid.org/0000-0003-2410-0412)
- Benjamin M. Tutolo (ORCID: https://orcid.org/0000-0002-3047-8828)
- David G. Burtt (ORCID: https://orcid.org/0009-0003-4461-0396)
- A. R. Vasavada
- D. T. Vaniman (ORCID: https://orcid.org/0000-0001-7661-2626)
- W. Rapin (ORCID: https://orcid.org/0000-0003-4660-8006)
- N. Castle (ORCID: https://orcid.org/0000-0002-0608-1249)
- S. J. Chipera (ORCID: https://orcid.org/0009-0006-0365-6277)
- Shaunna M. Morrison (ORCID: https://orcid.org/0000-0002-1712-8057)
- R. V. Morris (ORCID: https://orcid.org/0000-0003-1413-4002)
- Robert M. Hazen (ORCID: https://orcid.org/0000-0003-4163-8644)
- Robert T. Downs (ORCID: https://orcid.org/0000-0002-8380-7728)
- D. W. Ming (ORCID: https://orcid.org/0000-0003-0567-8876)
- Mattéo Loche (ORCID: https://orcid.org/0000-0003-0413-3305)
- P. D. Archer
Institutions
- Rutgers, The State University of New Jersey (US)
- California Institute of Technology (US)
- University of Copenhagen (DK)
- Ames Research Center (US)
- Centre National de la Recherche Scientifique (FR)
- Planetary Science Institute (US)
- Goddard Space Flight Center (US)
- Universities Space Research Association (US)
- Jet Propulsion Laboratory (US)
- University of Nevada, Las Vegas (US)
- Los Alamos National Laboratory (US)
- University of Arizona (US)
- University of Leicester (GB)
- University of Calgary (CA)
- Carnegie Institution for Science (US)
- Centre National d'Études Spatiales (FR)
- University of Chicago (US)
- Johnson Space Center (US)
- Institut de Recherche en Astrophysique et Planétologie (FR)
- Imperial College London (GB)
- Lunar and Planetary Institute (US)
- University of Maryland, College Park (US)
Publication Details
- Journal
- Science
- Published
- 2025-04-17
- DOI
- https://doi.org/10.1126/science.ado9966
- Citations
- 35
- Primary Topic
- Planetary Science and Exploration
- Type
- article
- Field-Weighted Citation Impact
- 40.42