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  Carbon cycle evolution before and after the Great Oxidation of the atmosphere

  Don E. Canfield

  American Journal of Science March 2021, 321 (3) 297-331; DOI: https://doi.org/10.2475/03.2021.01
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  Unmixing multiple metamorphic muscovite age populations with powder X-ray diffraction and ⁴⁰Ar/³⁹Ar analysis

  Ryan J. Mcaleer, David L. Bish, Michael J. Kunk, Peter M. Valley, Gregory J. Walsh and Robert P. Wintsch

  American Journal of Science March 2021, 321 (3) 332-364; DOI: https://doi.org/10.2475/03.2021.02
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  ⁴⁰Ar/³⁹Ar and LA-ICP-MS U–Pb geochronology for the New England portion of the Early Cretaceous New England-Quebec igneous province: Implications for the postrift evolution of the eastern North American Margin

  Jennifer R. Cooper Boemmels, Jean M. Crespi, Laura E. Webb and Julie C. Fosdick

  American Journal of Science March 2021, 321 (3) 365-391; DOI: https://doi.org/10.2475/03.2021.03