MET-IRSL used to track pre-depositional sediment transport history

This paper explores a series of single grain MET-IRSL (multiple elevated temperature infra-red stimulated luminescence) determinations undertaken in order to assess the potential of this approach, developed over the last decade and previously applied to a range of applications, in determining how eroded material moves through environments. Three different approaches are explored here, namely: i) an assessment of the potential to use the technique for improving the robustness of IRSL or P-IR-IRSL age estimates by identifying only well-bleached grains, ii) a means to characterise patterns of grain transport within a catchment using a newly established parameter, the “burial-bleach ratio”, and iii) a novel proxy that responds to changes in light availability through time, here referred to as palaeophotochronometry. For the second approach that we explore, a direct comparison of the MET-IRSL results from several sites with particle size analysis (PSA) data for the same sediment is included. This comparison highlights striking similarities between dispersal of single grain (SG) MET-IRSL burial-bleach ratio data and PSA distributions for some samples, suggesting that we may be able to place a timescale on the acquisition of this fundamental sedimentary characteristic. Common to these three SG MET-IRSL approaches is the importance of characterising and interpreting the previous bleaching records for individual grains.