| タイトル | Oxidative Alteration of Ferrous Smectites: A Formation Pathway for Martian Nontronite? |
| 本文（外部サイト） | http://hdl.handle.net/2060/20170001688 |
| 著者（英） | Catalano, J. G.; Agresti, D. G.; Nickerson, R. D.; Rivera-Banuchi, V.; Chemtob, S. M.; Yee, N.; Morris, R. V.; Liu, W. |
| 著者所属（英） | NASA Johnson Space Center |
| 発行日 | 2017-03-20 |
| 言語 | eng |
| 内容記述 | Ferric (Fe3+-bearing) smectites, including nontronite, constitute the majority of hydrous mineral exposures observed on Mars. These smectite exposures are commonly interpreted as weathering products of Martian basaltic crust. However, ferrous (Fe2+-dominated) smectites, not ferric, are the thermo-dynamically predicted products of weathering in anoxic conditions, as predicted for early Mars. Earth was anoxic until the Proterozoic Great Oxidation Event; Mars likely experienced an analogous oxidative evolution to its present oxidized state, but the timing of this evolution is unresolved. We hypothesize that Fe3+-smectites observed by orbital spectroscopy are not the initial products of Noachian-era chemical weathering, but are instead the oxidative products of primary Fe2+-smectites. To test this hypothesis experimentally, we synthesized ferrous smectites and exposed them to Mars-relevant oxidants. |
| NASA分類 | Lunar and Planetary Science and Exploration |
| レポートNO | JSC-CN-38832 |
| 権利 | Copyright, Distribution as joint owner in the copyright |
|
