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Science 17 May 1991:
Vol. 252. no. 5008, pp. 926 - 933
DOI: 10.1126/science.252.5008.926
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Articles

Core Formation During Early Accretion of the Earth

HORTON E. NEWSOM 1 and KENNETH W. W. SIMS 2

1 Institute of Meteoritics and Department of Geology, University of New Mexico, Albuguerque, NM 87131
2 Berkeley Center for Isotope Geochemistry, Department of Geology and Geophysics, University of California, Berkeley, Berkeley, CA 94720

Recent studies are leading to a better understanding of the formation of the earth's metal core. This new information includes: better knowledge of the physics of metal segregation, improved geochemical data on the abundance of siderophile and chalcophile elements in the silicate part of the earth, and experimental data on the partitioning behavior of siderophile and chalcophile elements. Extensive melting of the earth as a result of giant impacts, accretion, or the presence of a dense blanketing atmosphere is thought to have led to the formation of the core. Collision between a planet-sized body and the earth may have also produced the moon. Near the end of accretion, core formation evidently ceased as upper mantle conditions became oxidizing. The accumulation of the oceans is a consequence of the change to oxidizing conditions.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Coupled 186Os and 187Os Evidence for Core-Mantle Interaction.
A. D. Brandon, R. J. Walker, J. W. Morgan, M. D. Norman, and H. M. Prichard (1998)
Science 280, 1570-1573
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High-Pressure and High-Temperature Experiments on Core-Mantle Segregation in the Accreting Earth.
V. J. Hillgren, V. J. Hiligren, M. J. Drake, and D. C. Rubie (1994)
Science 264, 1442-1445
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Earth's early atmosphere.
J. Kasting (1993)
Science 259, 920-926
   Abstract »
Siderophile Elements and the Earth's Formation.
H. O'Neill (1992)
Science 257, 1282-1284
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Early Differentiation of the Earth and the Problem of Mantle Siderophile Elements: A New Approach.
V. Rama Murthy and V. R. MURTHY (1991)
Science 253, 303-306
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