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Reply to discussion of “Extracting K-Ar ages from shales: a theoretical test”

Published online by Cambridge University Press:  09 July 2018

J . Środoń*
Affiliation:
Institute of Geological Sciences PAN, Senacka 1, 31-002 Kraków, Poland

Abstract

As plots of K-Ar ages vs. percentage of the detrital component of mineral mixtures containing a detrital and a diagenetic illite (or illite-smectite) have different curved shapes, the linear extrapolation method of extracting the end-member ages is not justified. The curvature depends on the difference in K2O contents; thus it can be minimized if the percentage of detrital illite is normalized to the sum of detrital illite plus illitic fraction of diagenetic illite-smectite.

Type
Reply
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2000

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References

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