Meteorites at Meridiani Planum provide evidence for significant amounts of surface and near-surface water on early Mars

Alberto G. Fairén, James M. Dohm, Victor R. Baker, Shane D. Thompson, William C. Mahaney, Kenneth E. Herkenhoff, J. Alexis P. Rodríguez, Alfonso F. Davila, Dirk Schulze-Makuch, M. Ramy El Maarry, Esther R. Uceda, Ricardo Amils, Hirdy Miyamoto, Kyeong J. Kim, Robert C. Anderson, Christopher P. McKay

Research output: Contribution to journalArticle

14 Scopus citations

Abstract

Six large iron meteorites have been discovered in the Meridiani Planum region of Mars by the Mars Exploration Rover Opportunity in a nearly 25km-long traverse. Herein, we review and synthesize the available data to propose that the discovery and characteristics of the six meteorites could be explained as the result of their impact into a soft and wet surface, sometime during the Noachian or the Hesperian, subsequently to be exposed at the Martian surface through differential erosion. As recorded by its sediments and chemical deposits, Meridiani has been interpreted to have undergone a watery past, including a shallow sea, a playa, an environment of fluctuating ground water, and/or an icy landscape. Meteorites could have been encased upon impact and/or subsequently buried, and kept underground for a long time, shielded from the atmosphere. The meteorites apparently underwent significant chemical weathering due to aqueous alteration, as indicated by cavernous features that suggest differential acidic corrosion removing less resistant material and softer inclusions. During the Amazonian, the almost complete disappearance of surface water and desiccation of the landscape, followed by induration of the sediments and subsequent differential erosion and degradation of Meridiani sediments, including at least 10-80m of deflation in the last 3-3.5Gy, would have exposed the buried meteorites. We conclude that the iron meteorites support the hypothesis that Mars once had a denser atmosphere and considerable amounts of water and/or water ice at and/or near the surface.

Original languageEnglish (US)
Pages (from-to)1832-1841
Number of pages10
JournalMeteoritics and Planetary Science
Volume46
Issue number12
DOIs
StatePublished - Dec 2011

ASJC Scopus subject areas

  • Geophysics
  • Space and Planetary Science

Fingerprint Dive into the research topics of 'Meteorites at Meridiani Planum provide evidence for significant amounts of surface and near-surface water on early Mars'. Together they form a unique fingerprint.

  • Cite this

    Fairén, A. G., Dohm, J. M., Baker, V. R., Thompson, S. D., Mahaney, W. C., Herkenhoff, K. E., Rodríguez, J. A. P., Davila, A. F., Schulze-Makuch, D., El Maarry, M. R., Uceda, E. R., Amils, R., Miyamoto, H., Kim, K. J., Anderson, R. C., & McKay, C. P. (2011). Meteorites at Meridiani Planum provide evidence for significant amounts of surface and near-surface water on early Mars. Meteoritics and Planetary Science, 46(12), 1832-1841. https://doi.org/10.1111/j.1945-5100.2011.01297.x