Coupled Ferric Oxides and Sulfates on the Martian Surface

• Published in: Science (American Association for the Advancement of Science) 2007-08, Vol.317 (5842), p.1206-1210
• Main Authors: Bibring, J.-P, Arvidson, R.E, Gendrin, A, Gondet, B, Langevin, Y, Le Mouelic, S, Mangold, N, Morris, R.V, Mustard, J.F, Poulet, F, Quantin, C, Sotin, C
• Format: Article
• Language: English
• Subjects: Absorption spectra; Astrophysics; Cosmochemistry. Extraterrestrial geology; Earth Sciences; Earth, ocean, space; Exact sciences and technology; Extraterrestrial Environment; Extraterrestrial geology; Ferric Compounds; Geology; Hematite; Infrared reflection; Iron compounds; Mars; Oxides; Planetology; Sciences of the Universe; Signatures; Space exploration; Spectral reflectance; Spectral signatures; Sulfates; Water; Wavelengths
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1144174

The Mars Exploration Rover (MER), Opportunity, showed that layered sulfate deposits in Meridiani Planum formed during a period of rising acidic ground water. Crystalline hematite spherules formed in the deposits as a consequence of aqueous alteration and were concentrated on the surface as a lag deposit as wind eroded the softer sulfate rocks. On the basis of Mars Express Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité (OMEGA) orbital data, we demonstrate that crystalline hematite deposits are associated with layered sulfates in other areas on Mars, implying that Meridiani-like ground water systems were indeed widespread and representative of an extensive acid sulfate aqueous system.