Long-term stability of the TL signal in alkali feldspars

The long-term stability of the TL signal in alkali feldspars was investigated by studying infinitely old samples extracted from Tertiary sands. Mean lives in the range 800–5400 ka were obtained, indicating that long-term fading has to be taken into account. Fading corrections were calculated for a range of TL ages. The study indicated that the stability of the TL signal in alkali feldspars is less than that predicted from kinetic studies, and suggested a practical dating limit of 500 ka.