Wetherill diagramとは 意味・読み方・使い方

別の表記

• Wetherill concordia diagram

語源

Named after American physicist George Wetherill. From circa 1956.

名詞

Wetherill diagram (複数形 Wetherill diagrams)

1. (geology, geochronology) A type of concordia diagram, used in the context of uranium–lead dating, whose axes are the ratios ²⁰⁶Pb/²³⁸U and ²³⁷Pb/²³⁵Pb.

   The "x" and "y" axes of the Wetherill diagram are the quantities of the respective end (lead) isotopes of the actinium series and uranium series decay chains, each adjusted and expressed as a ratio to the amount remaining of the corresponding start (uranium) isotope.

   In the Wetherill diagram, no isotope is found on both axes, allowing the two decay schemes to be evaluated independently.

   • 1983, V. P. Grudina (translator), Lazarus J. Salop, Geological Evolution of the Earth During the Precambrian, Springer, page 50,

     However, these workers suggest that the age of the Amitsoq gneisses is closer to the true one when determined by the U-Th-Pb method on zircons, and the zircon isochron on the Wetherill diagram crosses the concordia in the point corresponding to 3600 m.y.

   • 2014, K. Stephen Hughes, et al., 2: Geology, Geochemistry and Geochronology of the western Piedmont of northern Virginia, Christopher M. Bailey, Lorrie V. Coiner (editors), Elevating Geoscience in the Southeastern United States, Geological Society of America, page 57,

     The fifth analysis shows signs of ${\displaystyle {\ce {Pb}}}$ loss and plots below the concordia line on the Wetherill diagram.

   • 2020, Myint Myat Phyo, et al., U—Pb Dating of Zircon and Zirconolite Inclusions in Marble-Hosted Gem-Quality Ruby and Spinel from Mogok, Myanmar, Frederick Lin Sutherland, Khin Zaw (editors), Mineralogy and Geochemistry of Ruby, MDPI Books, page 115,

     Figure 4. Wetherill diagrams showing wide range of ${\displaystyle {\ce {U-Pb}}}$ age of (a) zircon inclusion in gem-quality ruby and spinel, (b) accessory zircon in Bawlongyi marble, (c) zirconolite inclusion in ruby from Mansin and (d) zirconolite intergrown with zircon in Bawlongyi marble.