Articles | Volume 2, issue 2
https://doi.org/10.5194/gchron-2-355-2020
https://doi.org/10.5194/gchron-2-355-2020
Research article
 | 
26 Nov 2020
Research article |  | 26 Nov 2020

Production of 40Ar by an overlooked mode of 40K decay with implications for K-Ar geochronology

Jack Carter, Ryan B. Ickert, Darren F. Mark, Marissa M. Tremblay, Alan J. Cresswell, and David C. W. Sanderson

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Cited articles

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Altherr, R., Mertz-Kraus, R., Volker, F., Kreuzer, H., Henjes-Kunst, F., and Lange, U.: Geodynamic setting of Upper Miocene to Quaternary alkaline basalts from Harrat al `Uwayrid (NW Saudi Arabia): Constraints from KAr dating, chemical and Sr-Nd-Pb isotope compositions, and petrological modelling, Lithos, 330, 120–138, https://doi.org/10.1016/j.lithos.2019.02.007, 2019. 
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Short summary
40K is an isotope of potassium that undergoes several different modes of radioactive decay. We use the decay of 40K to determine the ages of geologic materials that contain potassium but doing this requires us to know the rate at which 40K decays by its different decay modes. Here, we investigate one decay mode of 40K that has previously been overlooked. We demonstrate that this decay mode exists, estimate its rate, and evaluate its significance for geochronology.