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Ehlmann BL, Mustard JF, Murchie SL, Poulet F, Bishop JL, Brown AJ, Calvin WM, Clark RN, Marais DJD, Milliken RE, Roach LH, Roush TL, Swayze GA, Wray JJ. Orbital identification of carbonate-bearing rocks on Mars. Science 2009; 322:1828-32. [PMID: 19095939 DOI: 10.1126/science.1164759] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Geochemical models for Mars predict carbonate formation during aqueous alteration. Carbonate-bearing rocks had not previously been detected on Mars' surface, but Mars Reconnaissance Orbiter mapping reveals a regional rock layer with near-infrared spectral characteristics that are consistent with the presence of magnesium carbonate in the Nili Fossae region. The carbonate is closely associated with both phyllosilicate-bearing and olivine-rich rock units and probably formed during the Noachian or early Hesperian era from the alteration of olivine by either hydrothermal fluids or near-surface water. The presence of carbonate as well as accompanying clays suggests that waters were neutral to alkaline at the time of its formation and that acidic weathering, proposed to be characteristic of Hesperian Mars, did not destroy these carbonates and thus did not dominate all aqueous environments.
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Affiliation(s)
- Bethany L. Ehlmann
- Department of Geological Sciences, Brown University, Providence, RI02912, USA
- Johns Hopkins University/Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
- Institut d'Astrophysique Spatiale, Université Paris Sud 11, 91405 Orsay, France
- SETI Institute and NASA Ames Research Center, 515 North Whisman Road, Mountain View, CA 94043, USA
- Department of Geological Sciences and Engineering, University of Nevada, MS 172, 1664 North Virginia Street, Reno, NV 89557, USA
| | - John F. Mustard
- Department of Geological Sciences, Brown University, Providence, RI02912, USA
- Johns Hopkins University/Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
- Institut d'Astrophysique Spatiale, Université Paris Sud 11, 91405 Orsay, France
- SETI Institute and NASA Ames Research Center, 515 North Whisman Road, Mountain View, CA 94043, USA
- Department of Geological Sciences and Engineering, University of Nevada, MS 172, 1664 North Virginia Street, Reno, NV 89557, USA
| | - Scott L. Murchie
- Department of Geological Sciences, Brown University, Providence, RI02912, USA
- Johns Hopkins University/Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
- Institut d'Astrophysique Spatiale, Université Paris Sud 11, 91405 Orsay, France
- SETI Institute and NASA Ames Research Center, 515 North Whisman Road, Mountain View, CA 94043, USA
- Department of Geological Sciences and Engineering, University of Nevada, MS 172, 1664 North Virginia Street, Reno, NV 89557, USA
| | - Francois Poulet
- Department of Geological Sciences, Brown University, Providence, RI02912, USA
- Johns Hopkins University/Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
- Institut d'Astrophysique Spatiale, Université Paris Sud 11, 91405 Orsay, France
- SETI Institute and NASA Ames Research Center, 515 North Whisman Road, Mountain View, CA 94043, USA
- Department of Geological Sciences and Engineering, University of Nevada, MS 172, 1664 North Virginia Street, Reno, NV 89557, USA
| | - Janice L. Bishop
- Department of Geological Sciences, Brown University, Providence, RI02912, USA
- Johns Hopkins University/Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
- Institut d'Astrophysique Spatiale, Université Paris Sud 11, 91405 Orsay, France
- SETI Institute and NASA Ames Research Center, 515 North Whisman Road, Mountain View, CA 94043, USA
- Department of Geological Sciences and Engineering, University of Nevada, MS 172, 1664 North Virginia Street, Reno, NV 89557, USA
| | - Adrian J. Brown
- Department of Geological Sciences, Brown University, Providence, RI02912, USA
- Johns Hopkins University/Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
- Institut d'Astrophysique Spatiale, Université Paris Sud 11, 91405 Orsay, France
- SETI Institute and NASA Ames Research Center, 515 North Whisman Road, Mountain View, CA 94043, USA
- Department of Geological Sciences and Engineering, University of Nevada, MS 172, 1664 North Virginia Street, Reno, NV 89557, USA
| | - Wendy M. Calvin
- Department of Geological Sciences, Brown University, Providence, RI02912, USA
- Johns Hopkins University/Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
- Institut d'Astrophysique Spatiale, Université Paris Sud 11, 91405 Orsay, France
- SETI Institute and NASA Ames Research Center, 515 North Whisman Road, Mountain View, CA 94043, USA
- Department of Geological Sciences and Engineering, University of Nevada, MS 172, 1664 North Virginia Street, Reno, NV 89557, USA
| | - Roger N. Clark
- Department of Geological Sciences, Brown University, Providence, RI02912, USA
- Johns Hopkins University/Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
- Institut d'Astrophysique Spatiale, Université Paris Sud 11, 91405 Orsay, France
- SETI Institute and NASA Ames Research Center, 515 North Whisman Road, Mountain View, CA 94043, USA
- Department of Geological Sciences and Engineering, University of Nevada, MS 172, 1664 North Virginia Street, Reno, NV 89557, USA
| | - David J. Des Marais
- Department of Geological Sciences, Brown University, Providence, RI02912, USA
- Johns Hopkins University/Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
- Institut d'Astrophysique Spatiale, Université Paris Sud 11, 91405 Orsay, France
- SETI Institute and NASA Ames Research Center, 515 North Whisman Road, Mountain View, CA 94043, USA
- Department of Geological Sciences and Engineering, University of Nevada, MS 172, 1664 North Virginia Street, Reno, NV 89557, USA
| | - Ralph E. Milliken
- Department of Geological Sciences, Brown University, Providence, RI02912, USA
- Johns Hopkins University/Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
- Institut d'Astrophysique Spatiale, Université Paris Sud 11, 91405 Orsay, France
- SETI Institute and NASA Ames Research Center, 515 North Whisman Road, Mountain View, CA 94043, USA
- Department of Geological Sciences and Engineering, University of Nevada, MS 172, 1664 North Virginia Street, Reno, NV 89557, USA
| | - Leah H. Roach
- Department of Geological Sciences, Brown University, Providence, RI02912, USA
- Johns Hopkins University/Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
- Institut d'Astrophysique Spatiale, Université Paris Sud 11, 91405 Orsay, France
- SETI Institute and NASA Ames Research Center, 515 North Whisman Road, Mountain View, CA 94043, USA
- Department of Geological Sciences and Engineering, University of Nevada, MS 172, 1664 North Virginia Street, Reno, NV 89557, USA
| | - Ted L. Roush
- Department of Geological Sciences, Brown University, Providence, RI02912, USA
- Johns Hopkins University/Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
- Institut d'Astrophysique Spatiale, Université Paris Sud 11, 91405 Orsay, France
- SETI Institute and NASA Ames Research Center, 515 North Whisman Road, Mountain View, CA 94043, USA
- Department of Geological Sciences and Engineering, University of Nevada, MS 172, 1664 North Virginia Street, Reno, NV 89557, USA
| | - Gregg A. Swayze
- Department of Geological Sciences, Brown University, Providence, RI02912, USA
- Johns Hopkins University/Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
- Institut d'Astrophysique Spatiale, Université Paris Sud 11, 91405 Orsay, France
- SETI Institute and NASA Ames Research Center, 515 North Whisman Road, Mountain View, CA 94043, USA
- Department of Geological Sciences and Engineering, University of Nevada, MS 172, 1664 North Virginia Street, Reno, NV 89557, USA
| | - James J. Wray
- Department of Geological Sciences, Brown University, Providence, RI02912, USA
- Johns Hopkins University/Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
- Institut d'Astrophysique Spatiale, Université Paris Sud 11, 91405 Orsay, France
- SETI Institute and NASA Ames Research Center, 515 North Whisman Road, Mountain View, CA 94043, USA
- Department of Geological Sciences and Engineering, University of Nevada, MS 172, 1664 North Virginia Street, Reno, NV 89557, USA
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