pure and applied geophysics

, Volume 63, Issue 1, pp 153–160 | Cite as

A gamma spectrometric study of Mont-Blanc granite samples

  • Ladislaus Rybach
  • Jürgen von Raumer
  • John A. S. Adams


Gamma-ray spectra of the samples were measured by standard laboratory multichannel spectrometry. The weighted least squares method was applied to the digital output data in order to determine the concentrations of U238, Th232 and K40 present. U and Th increase towards the rim of the massif (from 4 ppm U and 20 ppm Th in the coarse-grained central facies to 23 ppm U and 42 ppm Th in the fine-grained rim variety), whereas K remains fairly constant at ∼3.85%.


Th232 Standard Laboratory Output Data U238 Digital Output 
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Copyright information

© Birkhäuser Verlag 1966

Authors and Affiliations

  • Ladislaus Rybach
    • 1
  • Jürgen von Raumer
    • 2
  • John A. S. Adams
    • 1
  1. 1.Department of GeologyRice UniversityHouston(USA)
  2. 2.Mineralogisches InstitutUniversität Freiburg(Switzerland)

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