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

@article{Touboul2007LateFA,
  title={Late formation and prolonged differentiation of the Moon inferred from W isotopes in lunar metals},
  author={Mathieu Touboul and Thorsten Kleine and Bernard Bourdon and H. Palme and Rainer Wieler},
  journal={Nature},
  year={2007},
  volume={450},
  pages={1206-1209}
}
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. The timescales for formation and solidification of the Moon can be quantified by using 182Hf–182W and 146Sm–142Nd chronometry, but these methods have yielded contradicting results. In earlier studies, 182W anomalies in lunar rocks were attributed to decay of 182Hf within the lunar mantle and were… 
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References

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Hf-W Chronometry of Lunar Metals and the Age and Early Differentiation of the Moon
TLDR
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, consistent with the giant impact hypothesis and defines the completion of the major stage of Earth's accretion.
THE Hf-W ISOTOPIC SYSTEM AND THE ORIGIN OF THE EARTH AND MOON
▪ Abstract The Earth has a radiogenic W-isotopic composition compared to chondrites, demonstrating that it formed while 182Hf (half-life 9 Myr) was extant in Earth and decaying to 182W. This implies
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