Bleachability of pIRIR signal from single-grain K-feldspar     

《Quaternary Geochronology》2022

The high-temperature (e.g., >200 °C) post-infrared infrared (pIRIR) stimulated luminescence of feldspar has been widely used for dating, because it usually suffers negligibly from anomalous fading. However, compared to the quartz optically stimulated luminescence (OSL) or low-temperature (e.g., 50 °C) IR stimulated luminescence (IRSL) from feldspars, the high-temperature pIRIR signals have been shown to bleach more slowly and usually have high residual does of a few Gys or more, which limits its application to date relatively young samples and may cause problems for correcting residual dose/signal. In this study, we investigated the bleachability of K-feldspar pIRIR signals for individual grains. A significant variation in the bleachability of the pIRIR signal was observed among different K-feldspar grains from the same sample. Experiments show that such a variability may result in different residual doses for different grains and, consequently, additional scatter in D_e values. We present a method for quickly testing the bleachability of individual grains. Our result suggests that selecting the easy-to-bleach grains for D_e determination provides an efficient way to date young samples using high-temperature pIRIR signals, which avoids the compromise of using low-temperature pIRIR signals that may suffer from anomalous fading.  相似文献