It is important to remove the thermally unstable charges before luminescence measurement to avoid age underestimation in luminescence dating. The routine method is preheating. In this paper
the relationship between ED and preheating time and temperature
and the relationship between (N+β )/N ratio and preheating temperature were studied for the IRSL dating of Chinese lpess. It is concluded that 5 or 10min at 200-250℃
or 6h at 160℃ is a suitable preheating condition for the IRSL dating of Chinese loess.