“…Recent analyses at Gusev Crater and Meridiani Planum (Landis et al, 2004;Rieder et al, 2004) support these findings. There is no data regarding S-or Cspeciation; however the Viking analyses suggest S 6ϩ (Toulmin et al, 1977) and sulfate and carbonate salts have been tentatively identified in the martian dust using infrared spectroscopy (Bell, 1996;Blaney, 2001;Cooper and Mustard, 2002;Bandfield et al, 2003;Christensen et al, 2004). Because sulfate and carbonate salts are relatively soluble (e.g., species derived from salts with small log K in Table 1), any surface solutions in contact with dust must have been a brine such as "dirty water ice" (Christensen, 2003) or a high salinity brine(s) (Brass, 1980).…”