Highly siderophile elements in Earth’s mantle as a clock for the Moon-forming impact

  title={Highly siderophile elements in Earth’s mantle as a clock for the Moon-forming impact},
  author={Seth Andrew Jacobson and Alessandro Morbidelli and Sean N. Raymond and David P. O'Brien and Kevin J. Walsh and David C. Rubie},
According to the generally accepted scenario, the last giant impact on Earth formed the Moon and initiated the final phase of core formation by melting Earth’s mantle. A key goal of geochemistry is to date this event, but different ages have been proposed. Some argue for an early Moon-forming event, approximately 30 million years (Myr) after the condensation of the first solids in the Solar System, whereas others claim a date later than 50 Myr (and possibly as late as around 100 Myr) after… 
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Highly Siderophile Element Constraints on Accretion and Differentiation of the Earth-Moon System
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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
    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.
Making the Moon from a Fast-Spinning Earth: A Giant Impact Followed by Resonant Despinning
Computer simulations show that a giant impact on early Earth could lead to a Moon with a composition similar to Earth’s, and shows that a faster-spinning early Earth-Moon system can lose angular momentum and reach the present state through an orbital resonance between the Sun and Moon.
The osmium isotopic composition of the Earth's primitive upper mantle
THE elevated abundances of highly siderophile elements in the Earth's mantle, relative to what would be predicted from metal–silicate equilibrium, have often been cited as evidence for the accretion
The Absolute Chronology and Thermal Processing of Solids in the Solar Protoplanetary Disk
U-corrected Pb-Pb dating from primitive meteorites indicates that chondrule formation started contemporaneously with CAIs and lasted ~3 million years, suggesting that the formation ofCAIs and chondrules reflects a process intrinsically linked to the secular evolution of accretionary disks.