Abstract
Model compositions of Earth, Venus, and Mercury are calculated from the premise that planets and chondrites underwent four identical fractionation processes in the solar nebula. Because elements of similar properties stay together in these processes, five constraints suffice to define the composition of a planet: mass of the core, abundance of U, and the ratios K/U, Tl/U, and FeO/(FeO + MgO). Complete abundance tables, and normative mineralogies, are given for all three planets. Review of available data shows only a few gross trends for the inner planets: FeO decreases with heliocentric distance, whereas volatiles are depleted and refractories are enriched in the smaller planets.
Keywords: planets, solar nebula, element abundances, mantle, core
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- Ahrens T. J. Dynamic compression of Earth materials. Science. 1980 Mar 7;207(4435):1035–1041. doi: 10.1126/science.207.4435.1035. [DOI] [PubMed] [Google Scholar]
- Anders E., Owen T. Mars and Earth: origin and abundance of volatiles. Science. 1977 Nov 4;198(4316):453–465. doi: 10.1126/science.198.4316.453. [DOI] [PubMed] [Google Scholar]
- Lewis J. S. The temperature gradient in the solar nebula. Science. 1974 Nov 1;186(4162):440–443. doi: 10.1126/science.186.4162.440. [DOI] [PubMed] [Google Scholar]
- Pollack J. B., Black D. C. Implications of the gas compositional measurements of pioneer venus for the origin of planetary atmospheres. Science. 1979 Jul 6;205(4401):56–59. doi: 10.1126/science.205.4401.56. [DOI] [PubMed] [Google Scholar]
- Wasserburg G. J., Macdonald G. J., Hoyle F., Fowler W. A. Relative Contributions of Uranium, Thorium, and Potassium to Heat Production in the Earth. Science. 1964 Jan 31;143(3605):465–467. doi: 10.1126/science.143.3605.465. [DOI] [PubMed] [Google Scholar]