Hf-W Chronometry of Lunar Metals and the Age and Early Differentiation of the Moon
Abstract
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 defines the completion of the major stage of Earth's accretion.
- Publication:
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Science
- Pub Date:
- December 2005
- DOI:
- Bibcode:
- 2005Sci...310.1671K
- Keywords:
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- GEOCHEM PHYS