Application of a post-violet IR single-aliquot regenerative-dose (pVIR-SAR) protocol for natural polymineral fine and coarse-grain samples

Abstract Our group has previously characterised a post-violet infrared stimulated luminescence (pVIRSL) signal and developed a post-violet infrared single-aliquot regenerative-dose (pVIR-SAR) protocol for estimation of paleodoses. The protocol provides an opportunity for measuring polymineral samples as violet stimulation prior to IRSL measurement, bleaches natural luminescence signal of quartz, and makes it possible to probe photo-transferred charges in feldspar through IR stimulation. This study presents the results of the pVIR-SAR protocol on natural polymineral fine- (4–11 μm) and coarse-grain (90–150 μm) samples, including volcanic ash, pottery, and fluvial deposits from varied geological provenances. The results show that pVIR-SAR ages of both these fine- and coarse-grain samples are consistent with geological reasoning and available age controls thereby suggest that with the use of the pVIR-SAR protocol, mineral separation can be dispensed. This study also reports on the bleachability, athermal fading rates, and alpha efficiencies of pVIRSL for these samples and corresponding results are compared with IRSL at 50°C and post-IR IRSL (pIRIRSL) at 290°C. The pVIRSL signal has a better bleachability and reproducibility compared to the pIRIRSL signal. For the fluvial deposits dated in this study, the fine-grain samples provide ages consistent with the expected chronology.