Crystallization of Yamato 980459 at 0.5 GPA: Are Residual Liquids Like QUE 94201?

The Martian basaltic meteorites Y980459 and QUE94201 (henceforth referred to as Y98 and QUE respectively) are thought to represent magmatic liquid compositions [1-4], rather than being products of protracted crystallization and accumulation like the majority of other martian meteorites. Both meteorite compositions have been experimentally crys-tallized at 1 bar [2,4], and liquidus phases were found to match corresponding mineral core compositions in the meteorites, consistent with the notion that these meteorites represent bona fide melts. They also represent the most primitive and most evolved basaltic martian samples, respectively. Y98 has Mg# (molar Mg/Mg+Fe) ~ 65 [4], and lacks plagioclase; whereas QUE has Mg# ~ 40 [5], and lacks olivine. However they share important geochemical characteristics (e.g. superchondritic CaO/Al