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Call for an improved set of decay constants for geochronological use
The accuracy of radioisotopic ages is, at present, limited by the accuracy of radioactive decay constants. A literature survey reveals that decay constants used in geo- and cosmochronology usuallyExpand
Age and isotopic relationships among the angrites Lewis Cliff 86010 and Angra dos Reis
Results of a wide-ranging isotopic investigation of the unique Antarctican angrite LEW-86010 (LEW) are presented, together with a reassessment of the type angrite Angra dos Reis (ADOR). The principalExpand
60Fe: A Heat Source for Planetary Differentiation from a Nearby Supernova Explosion
From a sample of the Semarkona (LL 3.0) ordinary chondrite we report the in situ discovery of 60Ni isotopic anomalies attributable to the decay of short-lived 60Fe (half-life 1.5 Myr) in the mineralExpand
Samarium-146 in the Early Solar System: Evidence from Neodymium in the Allende Meteorite
A carbon-chromite fraction from the Allende C3V chondrite shows strikingly large isotopic enrichments of neodymium-142 and neodynium- 143, providing an improved estimate of the original abundance of extinct samarium-146 in the early solar system. Expand
60Fe in eucrites
Additional evidence for the existence in the early solar system of live60Fe has been found in the basaltic achondrite Juvinas. The relative abundance of 60Fe/56Fe of x0223C; 4 × 10−10 at the time ofExpand
Nickel and chromium isotopes in Allende inclusions
High-precision nickel and chromium isotopic measurements have been carried out on nine Allende inclusions.62Ni,64Ni excesses are present in at least three of the samples. The magnitudes of theExpand
Isotope and trace element characteristics of a super-fast spreading ridge: East Pacific rise, 13-23°S
Isotopic patterns of Nd, Sr, and Pb are remarkably coherent along the super-fast spreading portion of the East Pacific Rise from 13°S to 23°S. Between 15.8°S and 20.7°S, all three define a broad,Expand
The Sm-Nd history of KREEP
Sm-Nd whole rock measurements on a variety of KREEP-rich samples from different landing sites are reported. Despite a variation of Nd and Sm concentrations of almost a factor of 3, the Sm-Nd ratios,Expand
Mn-Cr isotope systematics of the D'Orbigny angrite
We have conducted a detailed study of the Mn-Cr systematics of the angrite D'Orbigny. Here, we report Cr isotopic abundances and Mn/Cr ratios in olivine, pyroxene, glass, chromite, and bulk rockExpand
Columbia River volcanism - The question of mantle heterogeneity or crustal contamination
Basalts from the Columbia River flood basalt province of the northwestern U.S.A. show a large diversity in chemical and Nd and Sr isotopic compositions. 143Nd144Nd ranges from 0.51303 to 0.51208 andExpand