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Rb-Sr dating of alteration events in granitoids
Contributions to Mineralogy and Petrology, 1983Veins and other effects of low-grade metamorphism are often found in igneous rocks. A method for dating such veins is proposed. It is based on the presence of Ca-bearing, Rb-free minerals in the veins and their aureoles. The method is applicable if five conditions are satisfied.
Levi, Beatriz +2 more
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Rb‐Sr data structure ‐ a possible cause for differences in Rb‐Sr whole‐rock and U‐Pb zircon ages
GFF, 1994Abstract Differences between U‐Pb zircon and Rb‐Sr whole‐rock ages are often interpreted to be due to later geologic disturbances such as low‐grade metamorphism and slow cooling. Yet, apparently contrasting ages can also be due to erroneous ages derived from non‐ideal systems.
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RbSr studies of CI and CM chondrites
Geochimica et Cosmochimica Acta, 1979Rb-Sr whole rock analyses have been performed on 2 CI and 3 CM chondrites. Four of these stones (Ivuna, Orgueil, Cold Bokkeveld and Erakot) were previously studied in this laboratory and were shown to be discordant from a 4.6 Gyr isochron. The fifth, Murchison, was not previously studied.
David W Mittlefehldt, George W Wetherill
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Rb–Sr Geochronology (Igneous Rocks)
2013The preferential incorporation of Rb (following K) or Sr (following Ca) into different mineral structures, as well as their differing behaviors during closed system evolution of magmas by fractional crystallization, results in a wide range in Rb/Sr in mineral and whole rock compositions.
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Rb-Sr geochronology of Graham Land, Antarctica
Journal of the Geological Society, 1982Thirty-five new Rb-Sr whole-rock and mineral isochrons are reported for igneous rocks from Graham Land. Magmatism was essentially continuous but peaks of activity occurred in early Jurassic, early Cretaceous, late Cretaceous and Eocene times. The oldest dated granite is Triassic (209 ± 3 Ma).
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On ‘spurious’ correlations in Rb-Sr isochron diagrams
Lithos, 1982Abstract A general null hypothesis for isotope geochemistry states that the isotopic composition of an element is independent of its concentration or any other geochemical property of the population. ‘Spurious’ correlations between the ratios 87 Sr/ 86 Sr and 87 Rb/ 86 Sr (orRb/Sr), due to the common denominator effect, may be ruled out because ...
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The Rb−Sr (Rubidium-Strontium) system
Bulletin of Alloy Phase Diagrams, 1985openaire +1 more source