Terrestrial analogues of the surface rocks of Mars?

Evidence is presented which suggests that hisingerite, iddingsite, and several ferric sulfate minerals derived from deuteric alteration of iron-rich basalts on earth may provide clues to the evolutionary history of the surface of Mars. The characteristics of these minerals are pointed out, and their strong compositional and paragenetic similarities to Martian regolith materials are pointed out. These similarities are consistent with a mineral assemblage on Mars consisting of ferric-bearing phyllosilicate, sulfate, and oxyhydroxide phases. These phases could have been derived from postmagmatic deuteric alteration of volatile-rich iron-rich basaltic rocks containing fayalitic olivine, Fe pyroxenes, and accessory pyrrhotite.