Comparison of single-aliquot and single-grain MET-pIRIR D_e results for potassium feldspar samples from the Nihewan Basin, northen China

In this study we compared De results obtained from single-aliquot (SA) and single-grain (SG) measurements on potassium rich feldspars (K-feldspars) from the Nihewan Basin, north China, based on the multiple-elevated-temperature post-infrared infrared (MET-pIRIR) stimulated luminescence. Discrepancy was observed between the SA and SG De results. Potential reasons for such discrepancy, including residual doses, sensitivity changes, fading rates, internal dose rates, and/or the combination of these possibilities, were investigated. Our results indicate that the disagreement between the SA and SG De results are mainly caused by the different fading rates and, to a small extent, by the internal K contents variations of different grains. Our study highlights the importance to investigate the relationship of single-grain De values and the luminescence behavior of individual grains, such as brightness. For partial-bleached or post-depositional mixed K-feldspar samples, statistical analysis should be conducted only on the grains with the same fading rate.