Astronomy and Astrophysics – Astronomy
Scientific paper
Sep 2009
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009apj...702..707s&link_type=abstract
The Astrophysical Journal, Volume 702, Issue 1, pp. 707-715 (2009).
Astronomy and Astrophysics
Astronomy
13
Minor Planets, Asteroids, Planetary Systems: Protoplanetary Disks, Solar System: Formation, Stars: Agb And Post-Agb, Supernovae: General
Scientific paper
The relative abundances of calcium isotopes in the mass range 40-44 were measured in primitive and differentiated meteorites and igneous rocks from Earth and Mars in search of non-mass-dependent variations that could provide clues about early solar system processes. Most bulk samples of planetary materials have calcium isotopic compositions identical with Earth's within the current resolution of about 0.01% in 40Ca/44Ca. Possible exceptions include carbonaceous chondrites, some ordinary chondrites, and two samples of calcium-aluminum-rich inclusions, which have small excesses of 40Ca. The samples with 40Ca excesses are also known to have 50Ti and 135Ba excesses and 142Nd and 144Sm deficits. Collectively these data from refractory elements suggest that the planetary embryos represented by chondrites preserve isotopic heterogeneity that reflects different nucleosynthetic sources. No late admixture from a single nucleosynthetic source can explain all observations. The results are most compatible with variable proportions of material derived from Type II supernovae. The initial calcium isotope compositions of Earth and Mars are indistinguishable and similar to the 40Ca abundance found in some chondrites and all differentiated meteorites studied. It appears that isotopic heterogeneity in calcium was still present at the completion of disk formation but was homogenized during planetary accretion.
Depaolo Donald J.
Moynier Frédéric
Simon Justin I.
No associations
LandOfFree
Calcium Isotope Composition of Meteorites, Earth, and Mars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Calcium Isotope Composition of Meteorites, Earth, and Mars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Calcium Isotope Composition of Meteorites, Earth, and Mars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1272564