Zinc isotopic evidence for the origin of the Moon

  title={Zinc isotopic evidence for the origin of the Moon},
  author={Randal C. Paniello and James M. D. Day and Fr{\'e}d{\'e}ric Moynier},
Volatile elements have a fundamental role in the evolution of planets. But how budgets of volatiles were set in planets, and the nature and extent of volatile-depletion of planetary bodies during the earliest stages of Solar System formation remain poorly understood. The Moon is considered to be volatile-depleted and so it has been predicted that volatile loss should have fractionated stable isotopes of moderately volatile elements. One such element, zinc, exhibits strong isotopic fractionation… 

Gallium isotopic evidence for extensive volatile loss from the Moon during its formation

The isotopic difference of Ga between Earth and the Moon and the isotopic heterogeneity of the crustal ferroan anorthosites suggest that the volatile depletion occurred following the giant impact and during the lunar magma ocean phase.

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

High-precision Cr isotope measurements in terrestrial and lunar rocks reveal an enrichment in the lighter isotopes of Cr in the Moon compared with Earth’s mantle by 100 ± 40 ppm per atomic mass unit, consistent with Cr partitioning into an oxygen-rich vapor phase in equilibrium with the proto-Moon.

Silicon isotopes in angrites and volatile loss in planetesimals

Measurements of silicon isotope ratios in angrites, a class of meteorites dating from the first few million years after condensation of solids from the solar nebula, show angrites are enriched in the heavy isotopes of Si relative to chondritic meteorites by 50–100 ppm/amu.

Potassium isotopic evidence for a high-energy giant impact origin of the Moon

The K isotope result is inconsistent with the low-energy disk equilibration model, but supports the high-energy, high-angular-momentum giant impact model for the origin of the Moon.

Evaporative fractionation of volatile stable isotopes and their bearing on the origin of the Moon

  • J. DayF. Moynier
  • Geology, Physics
    Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
  • 2014
In this model, the volatile loss requires preferential delivery and retention of late-accreted volatiles to the Earth compared with the Moon, and Parent-body size and the existence of early atmospheres are likely to represent fundamental controls on planetary volatile retention or loss.

Extensive volatile loss during formation and differentiation of the Moon

It is found that ferroan anorthosites are isotopically heterogeneous, with some samples exhibiting high δ66Zn, along with alkali and magnesian suite samples, implying the possibility of isolated, volatile-rich regions in the Moon's interior.



Late formation and prolonged differentiation of the Moon inferred from W isotopes in lunar metals

The Moon is thought to have formed from debris ejected by a giant impact with the early ‘proto’-Earth and, as a result of the high energies involved, the Moon would have melted to form a magma ocean.

An Oxygen Isotope Model for the Composition of Mars

Abstract We derive the bulk chemical composition, physical properties, and trace element abundances of Mars from two assumptions: (1) Mars is the parent body for the Shergottite–Nakhlite–Chassignite

Volatile accretion history of the terrestrial planets and dynamic implications

Evidence is examined for the hypothesis that the Moon and the Earth were essentially dry immediately after the formation of the Moon—by a giant impact on the proto-Earth—and only much later gained volatiles through accretion of wet material delivered from beyond the asteroid belt.

A short timescale for terrestrial planet formation from Hf–W chronometry of meteorites

Measurements of tungsten isotope compositions and hafnium–tungsten ratios of several meteorites indicate that the bulk of metal–silicate separation in the Solar System was completed within <30 Myr, completely consistent with other evidence for rapid planetary formation.

High Pre-Eruptive Water Contents Preserved in Lunar Melt Inclusions

In situ measurements of water in lunar melt inclusions are reported; these samples of primitive lunar magma, by virtue of being trapped within olivine crystals before volcanic eruption, did not experience posteruptive degassing.