Single-grain TT-OSL bleaching characteristics: Insights from modern analogues and OSL dating comparisons

Lee James Arnold, Martina Demuro, Nigel A. Spooner, Gavin John Prideaux, Matthew C. McDowell, Aaron Bruce Camens, Elizabeth H. Reed, Josep María Parés, Juan Luis Arsuaga, Jose María Bermúdez de Castro, Eudald Carbonell

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Previous assessments of thermally transferred optically stimulated luminescence (TT-OSL) signal resetting in natural sedimentary settings have been based on relatively limited numbers of observations, and have been conducted primarily at the multi-grain scale of equivalent dose (De) analysis. In this study, we undertake a series of single-grain TT-OSL bleaching assessments on nineteen modern and geological dating samples from different sedimentary environments. Daylight bleaching experiments performed over several weeks confirm that single-grain TT-OSL signals are optically reset at relatively slow, and potentially variable, rates. Single-grain TT-OSL residual doses range between 0 and 24 Gy for thirteen modern samples, with >50% of these samples yielding weighted mean De values of 0 Gy at 2σ. Single-grain OSL and TT-OSL dating comparisons performed on well-bleached and heterogeneously bleached late Pleistocene samples from Kangaroo Island, South Australia, yield consistent replicate age estimates. Our results reveal that (i) single-grain TT-OSL residuals can potentially be reduced down to insignificant levels when compared with the natural dose range of interest for most TT-OSL dating applications; (ii) the slow bleaching properties of TT-OSL signals may not necessarily limit their dating applicability to certain depositional environments; and (iii) non-trivial differences may be observed between single-grain and multi-grain TT-OSL bleaching residuals in some modern samples. Collectively, these findings suggest that single-grain TT-OSL dating may offer advantages over multi-grain TT-OSL dating in certain complex depositional environments.

Original languageEnglish
Pages (from-to)45-51
Number of pages7
JournalQuaternary Geochronology
Volume49
DOIs
Publication statusPublished - 2019

Fingerprint Dive into the research topics of 'Single-grain TT-OSL bleaching characteristics: Insights from modern analogues and OSL dating comparisons'. Together they form a unique fingerprint.

Cite this