Investigation of fission fragment tracks in natural glasses

Results on studying fission fragment tracks in natural glasses are presented. The experiments constitute continuation of the activity cycle on the age determination of glasses and crystals by 238U spontaneous fission. It is shown that methodology for determining age of natural glasses makes it possible to perform reliable measurements up to 105 years, however it requires labour-consuming procedure for glass sequential layer-by-layer polishing, etching and serveying. The results obtained for samples from Thailand show that the age of these glasses is significantly underestimated. 8 refs., 2 figs