Hf-W Chronometry of Lunar Metals and the Age and Early Differentiation of the Moon

  title={Hf-W Chronometry of Lunar Metals and the Age and Early Differentiation of the Moon},
  author={Thorsten Kleine and Herbert Palme and Klaus Mezger and Alex N. Halliday},
  pages={1671 - 1674}
The use of hafnium-tungsten chronometry to date the Moon is hampered by cosmogenic tungsten-182 production mainly by neutron capture of tantalum-181 at the lunar surface. We report tungsten isotope data for lunar metals, which contain no 181Ta-derived cosmogenic 182W. The data reveal differences in indigenous 182W/184W of lunar mantle reservoirs, indicating crystallization of the lunar magma ocean 4.527 ± 0.010 billion years ago. This age is consistent with the giant impact hypothesis and… Expand
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.Expand
Tungsten isotopic evidence for disproportional late accretion to the Earth and Moon
Characterization of the hafnium–tungsten systematics of the lunar mantle will enable better constraints on the timescale and processes involved in the currently accepted giant-impact theory for the formation and evolution of the Moon, and for testing the late-accretion hypothesis. Expand
Tungsten Isotopes in Planets.
Tungsten isotopic data for meteorites show that the parent bodies of some differentiated meteorites accreted within 1 million years after Solar System formation, demonstrating that traces of Earth's earliest formative period have been preserved throughout Earth's history. Expand
Hf–W chronometry of core formation in planetesimals inferred from weakly irradiated iron meteorites
Abstract The application of Hf–W chronometry to determine the timescales of core formation in the parent bodies of magmatic iron meteorites is severely hampered by 182W burnout during cosmic rayExpand
Lu–Hf zircon evidence for rapid lunar differentiation
Abstract Zircons from the Apollo 14 polymict breccias 14304, 14305, and 14321 crystallized from highly incompatible-trace-element enriched sources over an extended period of early lunar history fromExpand
Tungsten isotopes in ferroan anorthosites: Implications for the age of the Moon and lifetime of its magma ocean
New W isotope data for ferroan anorthosites 60025 and 62255 and low-Ti mare basalt 15555 show that these samples, contrary to previous reports [Lee, D.C., et al., 1997. Science 278, 1098–1103; Lee,Expand
A young Moon-forming giant impact at 70–110 million years accompanied by late-stage mixing, core formation and degassing of the Earth
  • A. Halliday
  • Geology, Medicine
  • Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
  • 2008
New W isotope data for lunar metals demonstrate that the Moon formed late in isotopic equilibrium with the bulk silicate Earth (BSE), and the Rb–Sr age of the Moon is defined, which is significantly later than had been deduced from W isotopes based on model assumptions or isotopic effects now known to be cosmogenic. Expand
Tungsten isotopes and the origin of the Moon
Abstract The giant impact model of lunar origin predicts that the Moon mainly consists of impactor material. As a result, the Moon is expected to be isotopically distinct from the Earth, but it isExpand
Early differentiation of meteorites constrained by the Hf-W isotope system
Isotopic studies of meteorites and sampies from the Moon, Mars, and the Earth combined with astranomical observations of planet forming regions from our Solar System and extrasolar systems pravideExpand
Early differentiation of the Earth and the Moon
It is shown, based on new mass-balance calculations for Nd isotopes, that the presence of a hidden reservoir is difficult to reconcile with the combined 142Nd–143Nd systematics of the Earth's mantle. Expand


Age and Origin of the Moon
The age and origin of the moon have been studied with the use of the recently developed short-lived hafnium-tungsten chronometer (182Hf-182W, half-life of nine million years). The tungsten isotopicExpand
Cosmogenic tungsten and the origin and earliest differentiation of the Moon
The decay of formerly live 182Hf with a half-life of 9 Myr results in variations in the abundance of 182W in early solar system objects. Here we demonstrate that major excesses in 182W in some lunarExpand
The age of ferroan anorthosite 60025: oldest crust on a young Moon?
Abstract Sm Nd isotopic data for mineral separates from the ferroan anorthosite 60025 define a precise isochron of 4.44 ± 0.02Ga age. This age is roughly 110 m.y. younger than the formation of theExpand
On the age of KREEP
Many lunar highland rocks have been extensively metamorphosed during the late heavy bombardment of the Moon 3.9–4.0 AE ago. Rubidium and other, more volatile elements were preferentially mobilizedExpand
SmNd constraints on early lunar differentiation and the evolution of KREEP
The Sm-Nd systematics of lunar KREEP basalt 15386 reflects two chronologically distinct events in the development of the incompatible element-rich materials of the moon. The measured Sm-Nd mineralExpand
W-Hf isotope abundances and the early origin and evolution of the Earth-Moon system
Abstract The decay of the short-lived isotope 182Hf to the isotope 182W early in solar system history provides clues to the origin and evolution of the Earth and Moon. Current time-scales for theExpand
The W isotope composition of eucrite metals: constraints on the timing and cause of the thermal metamorphism of basaltic eucrites
Abstract Basaltic eucrites formed as lava flows at or near the surface of asteroid Vesta. After crystallization, most eucrites were affected by thermal metamorphism, the timing and cause of which areExpand
INVITED REVIEW. Magmatic evolution of the Moon
Abstract Although incomplete because of the imperfect and somewhat random sampling of rock types by the Apollo and Luna missions (1969-1976), the history of lunar magmatism has been reconstructed byExpand
182Hf-182W isotope systematics of chondrites, eucrites, and martian meteorites: Chronology of core formation and early mantle differentiation in Vesta and Mars
Abstract The timescale of accretion and differentiation of asteroids and the terrestrial planets can be constrained using the extinct 182Hf-182W isotope system. We present new Hf-W data for sevenExpand
The W isotope evolution of the bulk silicate Earth: constraints on the timing and mechanisms of core formation and accretion
The W isotope composition of the bulk silicate Earth exhibits a small but resolvable excess in the abundance of 182W relative to that found in chondrites, indicating that core formation in Earth tookExpand