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Missing salts on early Mars

Milliken, R. E. and Fischer, W. W. and Hurowitz, J. A. (2009) Missing salts on early Mars. Geophysical Research Letters, 36 (11). L11202. ISSN 0094-8276.

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Our understanding of the role of water on Mars has been profoundly influenced over the past several years by the detection of widespread aqueous alteration minerals. Clay minerals are found throughout ancient Noachian terrains and sulfate salts are abundant in younger Hesperian terrains, but these phases are rarely found together in the early Martian rock record. Full alteration assemblages are generally not recognized at local scales, hindering our ability to close mass balance in the ancient crust. Here we demonstrate the dissolution of basalt and subsequent formation of smectite results in an excess of cations that should reside with anions such as OH^−, Cl^−, SO^(2-)_3 SO^(2-)_4, SO^(2-)_4, or CO^(2-)_3 in a significant reservoir of complementary salts. Such salts are largely absent from Noachian terrains, yet the composition and/or fate of these ‘missing salts’ is critical to understanding the oxidation state and primary atmospheric volatile involved in crustal weathering on early Mars.

Item Type:Article
Related URLs:
URLURL TypeDescription
Milliken, R. E.0000-0003-3240-4918
Fischer, W. W.0000-0002-8836-3054
Hurowitz, J. A.0000-0002-5857-8652
Additional Information:© 2009 American Geophysical Union. Received 13 April 2009; accepted 8 May 2009; published 6 June 2009. The research described in this paper was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. We thank Nick Tosca and anonymous reviewer for comments that improved this manuscript.
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Subject Keywords:Mars; clays; climate
Issue or Number:11
Record Number:CaltechAUTHORS:20090813-130508420
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Official Citation:Milliken, R. E., W. W. Fischer, and J. A. Hurowitz (2009), Missing salts on early Mars, Geophys. Res. Lett., 36, L11202, doi:10.1029/2009GL038558.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:15013
Deposited By: Tony Diaz
Deposited On:14 Aug 2009 16:26
Last Modified:09 Mar 2020 13:19

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