Figure 2.

Representative charts of reactions with the modified Rosy Red Mars Phoenix Lander simulant water. Meteorite protoliths (ALH77005, Chassigny, and Nakhla) and Mars 2020 Perseverance rover sites (Máaz and Séítah) reacted at 373.15 K. All plots show the major minerals produced (kg) on the vertical axis; inset text shows dominant species at equilibrium in aqueous and gas phases. Equilibrium minerals, waters, and gases differ. Specifically, Máaz yields a minnesotaite–mesolite-annite assemblage (pyrophyllite- and mica-bearing, with zeolites) and Séítah models yield an antigorite–greenalite–daphnite–andradite assemblage (dominated by serpentine, chlorite, and hydrogarnet groups). Further, the expected aqueous Cl⁻ and H_2(aq) values diverge, and H₂:CH₄ ratios vary between models (see supplementary documents for specific values).