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Directly Dating Sedimentary Rocks

Published online by Cambridge University Press:  21 July 2017

E. Troy Rasbury
Department of Geosciences, Stony Brook University Stony Brook, NY 11794-2100,
Jennifer M. Cole
Lamont-Doherty Earth Observatory of Columbia University P.O. Box 1000, Palisades, NY 10964-8000,
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This contribution seeks to provide a summary of radiometric dating techniques that are currently applicable to Phanerozoic sedimentary deposits and therefore relevant to paleontologists. First we overview the assumptions necessary for radiometric dating and introduce isochrons and concordia diagrams as methods for calculating ages and evaluating isotope systematics. We then focus on the four most promising systems: U-Pb dating of carbonates, Re-Os dating of black shales, and U-Pb and Lu-Hf dating of phosphates. We review expected geochemical behavior of daughter and parent isotopes in the context of both marine and terrestrial depositional environments. A critical evaluation of previously published ages and potential directions for future work are provided.

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