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Constraining the Pleistocene environmental history of the Atacama: Extending the age range of luminescence dating

This projects aims to extend the age range of luminescence dating from ~0.2-0.4 Ma towards 1 Ma. The landscape of the Atacama is dominated by clastic deposits, and luminescence dating offers a widely applicable and versatile technique for constraining the timing of environmental changes. Extending the age range will enable the temporal gap between geochronological methods from other sub-projects to be spanned, for example, whereas the upper limit of radiocarbon dating is ~50 ka, the lower limit of 10Be cosmogenic burial dating is ~0.5 Ma. Luminescence dating exploits the time-dependent accumulation of charge within certain minerals such as quartz and feldspar. It is routinely applied to terrigenous sediments. Established luminescence dating methods, such as quartz single-aliquot regenerative dose dating, will be used in parallel with other geochronological techniques to establish a robust chronological framework for late Pleistocene environmental change within the Atacama. Following establishment of a chronology for cross-validation, a suite of novel luminescence approaches will be exploited which can extend the age range of luminescence dating, including (a) single-grain and single-aliquot post-IR IRSL dating of feldspar, (b) thermally-transferred OSL dating, (c) violet-stimulated luminescence dating, and (d) thermoluminescence dating of quartz and feldspar. Successfully extending the age-range of luminescence dating will not only enable precise age controls within this CRC project, but will also be of significant benefit to palaeoenvironmental research more generally.