A new hypothesis for the origin and redistribution of sulfates in the equatorial region of western Mars

Abstract

[1] The formation of sulfates on Mars has been under debate since they were identified by several Mars missions starting from the 1970s. We propose that sulfates formed as evaporites in enclosed standing bodies of water in the Valles Marineris area following the early alteration of Martian basaltic crust, were then elevated by the Tharsis uplift, and transported together with rock materials to Meridiani Planum by periodic outbursts of water, where they were deposited as sediments. The proposed model comprehensively addresses all forms of sulfate occurrences near the equator in the western Martian hemisphere and relates it to physiographic processes (volcanic, tectonic and sedimentary) affecting the Martian surface. Citation: Fan, C., D. Schulze-Makuch, A. G. Fairén, and J. A. Wolff (2008), A new hypothesis for the origin and redistribution of sulfates in the equatorial region of western Mars, Geophys. Res. Lett., 35, L06201,

CO2–SO2 clathrate hydrate formation on early Mars

“…Also, clays may have been formed during such favorable climatic excursions (see e.g. Fan et al, 2008 ;Murchie et al, 2009 ;Wray et al, 2011).…”

“…Sulfur is also part of soil and dust at the global scale at an average level of ~6.8 % (King and McLennan, 2010). It has been suggested that some sulfates could have been formed by evaporitic processes in the Valles Marineris region prior to Tharsis formation, then redistributed by fluvial transport to Meridiani Planum, where they are now observed, during the elevation of the Tharsis uplift (Fan et al, 2008). If so, sulfates detected in Hesperian terrains could have been formed in the Noachian.…”

Aluminum extracts in Antarctic paleosols: Proxy data for organic compounds and bacteria and implications for Martian paleosols

“…Tharsis appears to have formed in at least five major stages, which include magmatic-driven flooding, ponding in the northern plains to form water bodies ranging from lakes to oceans, and transient climatic perturbations (Scott et al, 1995;Dohm and Tanaka, 1999;Baker, 2001;Fairén et al, 2003;Dohm et al, 2001Dohm et al, , 2007Dohm et al, , 2008a. Such activity, which may have contributed significantly to the formation of sulfates (Fan et al, 2008), cannot be ruled out in the future (Dohm et al, 2008b).…”

The environment of early Mars and the missing carbonates

“…Furthermore, a recent study by Michalski and Niles (2010) adds a new piece to the carbonate puzzle of Mars; these authors report the occurrence of thick carbonate deposits below 6 km of basaltic crust at the bottom of deep Noachian deposits that have been exposed by a bolide impact. Although it is widely accepted that an acidic episode followed the formation of phyllosilicates on Mars, Fan et al. (2008) suggest that acidic conditions were reached during the Early Noachian as a consequence of the Tharsis uplift.…”