XVI INQUA Congress

Paper No. 4
Presentation Time: 1:30 PM-4:30 PM

CRITICISM OF TRADITIONAL TL-OSL DATING


SHLUKOV, A., S-T Laboratory, State Oceanographic Institute, Kropotkinski per. 6, Moscow, 119034, Russia, shlukov@marosnet.ru

TL-OSL dating is based on dosimetric property of some natural minerals, mainly quartz and feldspars. We have raised the question for many times regarding the competency of traditional technique of a dating which we consider to apply the artificial irradiation of samples to receive the natural absorbed doze.

The technique of artificial calibration has been borrowed from a TL dosimetry used in nuclear power engineering in conditions of high doze-rates. Specificity of TL-OSL dating is usage of artificial irradiation to model natural processes in a laboratory. So a natural background radiation with typical doze-rate 10-20 mkr/hour is being replaced by an artificial irradiation with a doze-rate up to 10-100 r/sek. Consequently the doze-rate changes by 7-9 orders. Such artificial calibration is competent only in case if a dosimeter has absolutely equal characteristics in such contrast conditions. However nobody and never has proved, that quartz or feldspars have the similar property.

It is well known from the theory of a luminescence, that such opportunity takes place only in case, if electrons-holes kinetics in crystal structure has the so-called first order. Such property was accepted in TL-OSL dating as a postulate. However, the kinetics of first order is realized usually in fast processes, at which excess energy holds in a crystal starting from a fraction of seconds (scintillation, fluorescence) to several months as maximum (TL dosimeters). This energy is being held during hundreds of millenniums in the geochronometry that is practically impossible at the first order. The second order kinetics take place usually in this case.

We observed experimentally all distinctive attributes of the second order kinetics in natural quartz. The final and full proof of the second order had been received in special experiment. Our results were reported last year at 10-th International Conference LED-2002. However this report was rejected from the Conference’s Proceedings. Nevertheless, this rejection cannot serve as the proof of the first order of the kinetics.