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Title: Solar System Abundances of the Elements
Updated solar photospheric abundances are compared with meteoritic abundances. The uncertainties of solar abundances of many trace elements are considerably reduced compared to the 2003 compilation. Some of the solar rare earth elements have now assigned errors of ± 5%, approaching the accuracy of meteorite analyses. The agreement between solar abundances and CI chondrites is further improved. Problematic elements with comparatively large differences between solar and meteoritic abundances are manganese, hafnium, rubidium, gallium, and tungsten. The CI chondrites match solar abundances in refractory lithophile, siderophile, and volatile elements. All other chondrite groups differ from CI chondrites. With analytical uncertainties, there are no obvious fractionations between CI meteorites and solar abundances. Further progress will primarily come from improved solar abundance determinations. The limiting factor in the accuracy of meteorite abundances is the inherent heterogeneity of CI chondrites, primarily the Orgueil meteorite. The interstellar medium (ISM) from which the solar system formed has the same composition as the Sun for volatile and moderately volatile elements within a factor of 2. The more refractory elements of the ISM are depleted from the gas and are concentrated in grains.  more » « less
Award ID(s):
1517541
PAR ID:
10036398
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Planets, Asteriods, Comets and The Solar System, Volume 2 of Treatise on Geochemistry (Second Edition). Edited by Andrew M. Davis. Elsevier, 2014., p.15-36
Volume:
2
Page Range / eLocation ID:
15-36
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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