Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5783477 | Geochimica et Cosmochimica Acta | 2017 | 42 Pages |
Abstract
At the ±1 and ±2 ε-unit levels, respectively, there is no measurable 40Ca or 43Ca anomaly in bulk chondrites. Carbonaceous chondrites show several ε-units of 48Ca excess. That is, Ca exhibits both mass-dependent and mass-independent isotopic variations in chondrites, similar to O isotopes. The 48Ca anomaly in bulk chondrites is positively correlated with 50Ti anomaly, but does not form simple correlation with 54Cr anomaly, implying multiple supernova sources for these neutron-rich isotopes in the Solar System. Finally, all meteorites with negative Î17O have either 48Ca deficits (differentiated meteorites) or 48Ca excess (carbonaceous chondrites), implying that the Sun with a very negative Î17O is probably also characterized by 48Ca anomaly compared to the Earth. CAIs cannot be taken as representative of the initial isotopic compositions of refractory elements like Ca for the Earth-Moon system.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Geochemistry and Petrology
Authors
Shichun Huang, Stein B. Jacobsen,