1. Formation of Tridymite and Evidence for a Hydrothermal History at Gale Crater, Mars
- Author
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Jürgen Berger, Heather B. Franz, Cherie N. Achilles, Thomas F. Bristow, R. Gellert, Steve J. Chipera, Elizabeth B. Rampe, David F. Blake, Scott VanBommel, C. D. O'Connell-Cooper, A. H. Treiman, Travis Gabriel, Richard V. Morris, B. C. Clark, Shaunna M. Morrison, David T. Vaniman, Susanne P. Schwenzer, B. Sutter, D. W. Ming, Robert T. Downs, Amy McAdam, Mariek E. Schmidt, N. I. Boyd, P. I. Craig, Albert S. Yen, and Lucy M. Thompson
- Subjects
geography ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,Geochemistry ,Silicic ,Mars Exploration Program ,01 natural sciences ,Hydrothermal circulation ,Volcanic rock ,Geophysics ,Tridymite ,Impact crater ,Space and Planetary Science ,Geochemistry and Petrology ,Sample Analysis at Mars ,Earth and Planetary Sciences (miscellaneous) ,Lithification ,0105 earth and related environmental sciences - Abstract
In August 2015, the Curiosity Mars rover discovered tridymite, a high‐temperature silica polymorph, in Gale crater. The existing model for its occurrence suggests erosion and detrital sedimentation from silicic volcanic rocks in the crater rim or central peak. The chemistry and mineralogy of the tridymite‐bearing rocks, however, are not consistent with silicic volcanic material. Using data from Curiosity, including chemical composition from the Alpha Particle X‐ray Spectrometer, mineralogy from the CheMin instrument, and evolved gas and isotopic analyses from the Sample Analysis at Mars instrument, we show that the tridymite‐bearing rocks exhibit similar chemical patterns with silica‐rich alteration halos which crosscut the stratigraphy. We infer that the tridymite formed in‐place through hydrothermal processes and show additional chemical and mineralogical results from Gale crater consistent with hydrothermal activity occurring after sediment deposition and lithification.
- Published
- 2021