Accretion of the earth and segregation of its core

ABSTRACT The Earth took 30–40 million years to accrete from smaller ‘planetesimals’. Many of these planetesimals had metallic iron cores and during growth of the Earth this metal

re-equilibrated with the Earth's silicate mantle, extracting siderophile (‘iron-loving’) elements into the Earth's iron-rich core. The current composition of the mantle indicates

that much of the re-equilibration took place in a deep (> 400 km) molten silicate layer, or ‘magma ocean’, and that conditions became more oxidizing with time as the Earth grew. The

high-pressure nature of the core-forming process led to the Earth's core being richer in low-atomic-number elements, notably silicon and possibly oxygen, than the cores of the smaller

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FAQs * Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS THE ACCRETION OF PLANET EARTH Article 29 November 2022 FORMATION AND COMPOSITION OF EARTH’S HADEAN PROTOCRUST Article

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are acknowledged with thanks. B.J.W. acknowledges the award of an ARC Federation Fellowship. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of Earth and Planetary Sciences,

Macquarie University, North Ryde, New South Wales, 2109, Australia Bernard J. Wood * Department of Earth Sciences, University of Bristol, Bristol, Queen's Road, BS8 1RJ, UK Michael J.

Walter & Jonathan Wade Authors * Bernard J. Wood View author publications You can also search for this author inPubMed Google Scholar * Michael J. Walter View author publications You can

also search for this author inPubMed Google Scholar * Jonathan Wade View author publications You can also search for this author inPubMed Google Scholar CORRESPONDING AUTHOR Correspondence

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