RECENT PROGRESS IN FISSION-TRACK ANALYSIS AND ITS APPLICATIONS IN CHINA

Fission track analysis (FTA) has been developed and applied in China since 1985. Since then great efforts have been made on methodology and applications. In order to improve the accuracy of fission track dating, zeta calibration constants have been determined against NBS SRM 962 standard uranium glass and seven age standards. TINT method and silver coating were used to increase the density and contrast of confined spontaneous fission tracks on apatite. Based on the fanning model of fission track annealing for apatite presented by Laslett, G, M. , a forward computer modeling of track shortening and age evolution was completed and an inverse method of modeling thermal histories from apatite fission track data is underway. Apatite fission track data (age and track length), zircon age and forward modeling method have been used to reveal thermal and tectonic histories of several sedimentary basins and of a collision zone in China. In this presentation some progress in methodology and application will be presented and discussed.