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Strontium Isotopes In Seawater Through Time
Annual Review of Earth and Planetary Sciences, 1989where pis the p-particle, v is an antineutrino, and Q represents the decay energy (0.275 MeV). The recommended decay constant for 87Rb is 1.42 x 10-11 yr-I (Steiger & Jager 1977), and its half-life T is therefore 48.8 Gyr. On geological time scales, the isotopes 84, 86, and 88 are stable, in contrast to 87Sr, and their abundance ratios are therefore ...
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Strontium Isotopic Composition of Mid-Cretaceous Seawater
Science, 1994The 87 Sr/ 86 Sr ratio in fish teeth separated from mid-Cretaceous marl and black shale from the northeastern Apennines and Venetian Alps (Italy) define three periods of low 87 Sr/ 86 Sr ratio at 121 to 124 million years ago (Ma), 110 to 115 Ma,
INGRAM B. LYNN +3 more
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Uses of Strontium Isotopes in Petrogenesis
1972The isotopic composition of strontium is not only a useful indicator of the ages of rocks and minerals, but it also contains information about the origin of igneous rocks and about the geologic processes that have affected their chemical compositions.
James L. Powell, Gunter Faure
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Strontium Isotope Fractionation in the Kiglapait Intrusion
Science, 1983The initial ratio of strontium-87 to strontium-86 rises systematically from 0.70395 to 0.70662 over the upper 10 percent of the Kiglapait layered intrusion. This ratio is strongly correlated with potassium and rubidium. Contamination, exchange, and magma mixing fail to account for the increase, which is ascribed to the imperfect retention of radiogenic
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A geochemical coincidence between strontium isotopes and lead isotopes
Chemical Geology, 1966Abstract It is shown that the extent of fractional crystallization, which is assumed to have given rise to the source material of common leads at the time of primeval differentiation of the earth can cover approximately the range of the 87 Sr 86 Sr ratio found in basalts.
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Variations in Isotopic Abundances of Strontium
Physical Review, 1953L. H. Ahrens +4 more
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Recent Developments for the Deuterium and Tritium Labeling of Organic Molecules
Chemical Reviews, 2022Sara Kopf, Florian Bourriquen, Wu Li
exaly