Ar‐Ar and U‐Pb Geochronology of a Late Paleoproterozoic Rift Basin: Support for a Genetic Link with Hudsonian Orogenesis, Western Churchill Province, Nunavut, Canada

The Baker Lake Group (Baker Sequence) represents the record of the formative stage of Baker Lake Basin, a series of generally elongate, northeast‐striking, half‐graben, and fault‐bounded troughs filled with continental redbeds and coeval voluminous ultrapotassic volcanic rocks. An estimate for the time of basin initiation is given by a U‐Pb (zircon) age of \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape $1833\pm 3$ \end{document} Ma, obtained from a basal volcanic flow at the western end of the basin, which is in agreeme...