1. http://www.psrd.hawaii.edu/Dec11/ALH84001_Carb.html Formation of Carbonates in Martian Meteorite ALH 84001: Cool Water Near the Surface of Mars Secondary carbonates in ancient orthopyroxenite ALH 84001 record key information about the environment of their formation. ALH 84001 igneous age (Ieft side of gray box) and carbonate age (right) fall in the period of active aqueous processes on Mars. Ehlmann et al. (2011 )

2. http://www.psrd.hawaii.edu/Dec11/ALH84001_Carb.html Clumped Isotope ThermometryClumped Isotope Thermometry Isotopologues of CO 2 differ in how much 12 C, 13 C, 16 O, 17 O, and 18 O they contain. Mass 47 is useful because it contains both 13 C and 18 O, which have a temperture- dependent preference for residing in the same molecule. The parameter  47 derives from the abundance ratios of masses 47 and 44, compared to the value expected if the isotopes are randomly distributed among the isotopologues. Experimental data like these and thermodynamic principles allow us to correlate  47 with temperature. The mean value of ALH 84001 implies 18°C (±4)

3. http://www.psrd.hawaii.edu/Dec11/ALH84001_Carb.html Evaporating Fluids, Precipitating CarbonatesEvaporating Fluids, Precipitating Carbonates Physical Model: Fractured near-surface of Mars is saturated at some depth with water. Evaporation causes carbonates to form. Little connection with the atmosphere, so evaporation causes correlated changes in  13 C and  18 O.