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arXiv · 1603.04536

Oxygen isotopic evidence for vigorous mixing during the Moon-forming Giant Impact

Edward D. Young·Issaku E. Kohl·Paul H. Warren·David C. Rubie·Seth A. Jacobson·Alessandro Morbidelli
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Abstract

Earth and Moon are shown here to be composed of oxygen isotope reservoirs that are indistinguishable, with a difference in {\Delta}"17O of -1 +/- 5ppm (2se). Based on these data and our new planet formation simulations that include a realistic model for oxygen isotopic reservoirs, our results favor vigorous mixing during the giant impact and therefore a high-energy high- angular-momentum impact. The results indicate that the late veneer impactors had an average {\Delta}"17O within approximately 1 per mil of the terrestrial value, suggesting that these impactors were water rich.

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Edward D. Young, Issaku E. Kohl, Paul H. Warren, David C. Rubie, Seth A. Jacobson, Alessandro Morbidelli. 2016-03-15. Oxygen isotopic evidence for vigorous mixing during the Moon-forming Giant Impact. https://doi.org/10.1126/science.aad0525

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