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

@article{Kleine2005HfWCO,
  title={Hf-W Chronometry of Lunar Metals and the Age and Early Differentiation of the Moon},
  author={Thorsten Kleine and H. Palme and Klaus Mezger and Alex N. Halliday},
  journal={Science},
  year={2005},
  volume={310},
  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… 
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