Volatile loss following cooling and accretion of the Moon revealed by chromium isotopes.

ABSTRACT: Terrestrial and lunar rocks share chemical and isotopic similarities in refractory elements, suggestive of a common precursor. By contrast, the marked depletion of volatile elements in lunar rocks together with their enrichment in heavy isotopes compared with Earth's mantle suggests that the Moon underwent evaporative loss of volatiles. However, whether equilibrium prevailed during evaporation and, if so, at what conditions (temperature, pressure, and oxygen fugacity) remain unconstrained. Chromium may shed light on this question, as it has several thermodynamically stable, oxidized gas species that can distinguish between kinetic and equilibrium regimes. Here, we present high-precision Cr isotope measurements in terrestrial and lunar rocks that reveal an enrichment in the lighter isotopes

SUBMITTER: Sossi PA 

PROVIDER: S-EPMC6205496 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature