Geodynamic Significance of the Kontum Massif in Central Vietnam: Composite 40Ar/39Ar and U‐Pb Ages from Paleozoic to Triassic

TLDR: The Kontum massif of southcentral Vietnam has long been classified as lower continental crust of Precambrian (Archean) age as discussed by the authors, however, these dates imply at least two Paleozoic thermal events.

Abstract: The Kontum massif of south‐central Vietnam has long been classified as lower continental crust of Precambrian (Archean) age. U‐Pb zircon and 40Ar/39Ar biotite ages from charnockites and amphibolite facies rocks from this basement, however, yield much younger ages and imply at least two Paleozoic thermal events. Syntectonic charnockites from the Kannack complex and the southern Kontum massif record Permo‐Triassic magmatism (U‐Pb: \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 $249\pm 2$ \end{document} [2σ] Ma and \docume...