Standardization of fission track dating methods

Abstract

In order for Fission Track Dating methods (F.T.D.) to be improved and definitively recognized, all laboratories need to agree upon the standards to be used. The first step in this standardization, which has now been repeated several times, was to collect from different laboratories the results of the samples to be dated with all the experimental conditions and constant values used for the calculation. Such experiments have been carried out mainly on apatites and zircons and the first conclusions were presented at Troy during the Fourth International Fission Track Dating Workshop. A consensus is still needed to decide which constant values should be used particularly for λ F. The differences which come about in experimentation should be reduced using standards with well known ages which should permit a factor 2 of experimental calibration to be deduced. Because the neutron fluence is generally not homogenous, a physical calibration with metallic dosimeters is the best method to be used. Only under such strict conditions will fission track dating results be widely accepted by the scientific community in the geochronology field. A new interlaboratory calibration is currently in progress for adopting international working procedures for future F.T.D. The 6th International Fission Track Dating Workshop which will be held in Besançon (France) next September, 1988 should resolve these problems.