Computer Science
Scientific paper
Jan 2010
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010e%26psl.289..457s&link_type=abstract
Earth and Planetary Science Letters, Volume 289, Issue 3-4, p. 457-466.
Computer Science
10
Scientific paper
New measurements of mass-dependent calcium isotope effects in meteorites, lunar and terrestrial samples show that Earth, Moon, Mars, and differentiated asteroids (e.g., 4-Vesta and the angrite and aubrite parent bodies) are indistinguishable from primitive ordinary chondritic meteorites at our current analytical resolution (± 0.07‰ SD for the 44Ca/40Ca ratio). In contrast, enstatite chondritic meteorites are slightly enriched in heavier calcium isotopes (ca. + 0.5‰) and primitive carbonaceous chondritic meteorites are depleted in heavier calcium isotopes (ca. - 0.5‰). The calcium isotope effects cannot be easily ascribed to evaporation or intraplanetary differentiation processes. The isotopic variations probably survive from the earliest stages of nebular condensation, and indicate that condensation occurred under non-equilibrium (undercooled nebular gas) conditions. Some of this early high-temperature calcium isotope heterogeneity is recorded by refractory inclusions (Niederer and Papanastassiou, 1984) and survived in planetesimals, but virtually none of it survived through terrestrial planet accretion. The new calcium isotope data suggest that ordinary chondrites are representative of the bulk of the refractory materials that formed the terrestrial planets; enstatite and carbonaceous chondrites are not. The enrichment of light calcium isotopes in bulk carbonaceous chondrites implies that their compositions are not fully representative of the solar nebula condensable fraction.
Depaolo Donald J.
Simon Justin I.
No associations
LandOfFree
Stable calcium isotopic composition of meteorites and rocky planets 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 Stable calcium isotopic composition of meteorites and rocky planets, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stable calcium isotopic composition of meteorites and rocky planets will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1443511