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U/Th dating of impure carbonates: 230Th/232Th activity ratios in detrital material

  • A. Martínez-AguirreEmail author
  • J. M. Alcaraz-PelegrinaEmail author
  • J. Rodríguez-VidalEmail author
Article

Abstract

In environmental age dating the 230Th/232Th activity ratio is widely used as an indicator of detrital contamination. A clear relationship between this activity ratio and the carbonate sample’s age has previously been demonstrated, whereby a detrital correction must be applied when the 230Th/232Th activity ratio of the leach drops to 20. We demonstrate that in some cases carbonate samples with 230Th/232Th well above 20 must be corrected, otherwise an overestimation of the sample’s age is obtained. Evaluation of the relationship between 230Th/234U and 230Th/232Th in the carbonate’s aliquots will enable evaluation of the limit at which a carbonate can be considered pure or impure.

Keywords

U/Th dating Carbonates Detrital material Age corrections Radio chronometry 

Notes

Acknowledgements

This work was supported by the PaleoMed Project of Interreg IIIB of the EU MEDOC Programme: 2002-02-4.1-U-048, by the Government of Gibraltar and by Huelva University.

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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  1. 1.Department of Applied Physics I, ETSIAUniversity of SevilleSevilleSpain
  2. 2.Department of Physics, Edificio C-2University of CórdobaCórdobaSpain
  3. 3.Department of Earth SciencesUniversity of HuelvaHuelvaSpain

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