Testing the potential of a low temperature feldspar luminescence dating approach using yellow stimulation

• Applicant: Dr. Tobias Lauer
• Subject Area: Physical Geography
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 498100748

Robust dating methods are crucial to study the timing of past shifts in climate and palaeoenvironment. Luminescence dating is often used to establish chronological frameworks for terrestrial sediment archives and so called pIRIR protocols, in which the feldspar signal is stimulated at elevated temperatures after depleting the IR50 signal, are mostly applied to date sediments yielding an already saturated or generally problematic quartz luminescence signal. These elevated temperature measurements often show no or negligible fading but e.g. dose residuals can be problematic and lead to age overestimation what is especially relevant for Holocene or Upper Pleistocene sediments. With our research-campaign we aim at testing the potential of a post-IR yellow stimulated feldspar signal measured at low temperatures to better overcome problems such as high dose residuals or unwanted thermal transfer. Our hypothesis is to obtain a stable feldspar emission, which guides electrons via a sub-conduction band level. First studies on the approach, in which the yellow stimulated feldspar signal is measured at 50°C following an IR-bleach (named hereafter pIR-YOSL), show that the pIR-YOSL signal seems very promising to date Quaternary sediments. Therefore, we now want to systematically study the yellow stimulated signal in terms of emission-spectra, signal stability, saturation and bleachability. Furthermore we plan to test the protocol on a set of samples for which chronological control is available and spanning from Middle-Pleistocene to recent age.

• DFG Programme: Research Grants