Hf-W Isotopic Evidence for Rapid Accretion and Differentiation in the Early Solar System
The time scales over which inner solar system objects accreted and differentiated are unclear because the isotopic systems of many meteorites are disturbed. 182Hf decays to 182W with a half-life of 9 million years and is a particularly useful chronometer because both elements are highly refractory and immobile. Tungsten isotopic data for IIA, IIIA, IVA, and anomalous iron meteorites and H, L, and LL chondrites indicate that their parent bodies accreted rapidly and segregated metal within just a few million years.
Lee
DC
Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109-1063 USA.
Halliday
AN