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Abstract: We investigate the feasibility of a modified single-aliquot regenerative-dose (SAR) protocol for OSL dating of individual grains from young samples ( years) using dose-recovery tests. Parameters such as pre-heat temperature, test- and regenerative-dose size, an additional bleaching step at high-temperature and optical stimulation time are optimised to give the highest percentage of accepted grains. The optimised protocol makes use of a 50Gy test dose, a single regeneration dose of 5Gy, an additional bleaching step and an optical stimulation of 10s. This protocol is applied to two coastal-dune samples. Equivalent doses close to those obtained for multiple-grain single-aliquot measurements can be retrieved if: (1) short integration intervals (0.034s) are used for the natural and regenerated OSL signals as well as the test-dose responses and (2) the background is estimated from the subsequent 0.034s, and the net signals are used to determine the equivalent dose. Standard background subtraction methods lead to overestimation of the equivalent dose for these samples due to incorporation of a slow OSL component that was not completely reset at the time of burial. [Copyright &y& Elsevier]

Abstract: We investigate the use of different optical detection filters for single-grain optically stimulated luminescence (OSL) measurements of quartz samples with a Risø TL/OSL single-grain reader. We selected three filter combinations that considerably improve the light detection efficiency when compared with the 7.5mm U340 filters that are routinely used. These are the UG1+BG4 filter combination, the 2mm UG1 and the 2.5mm U340 filters, which allow a greater transmission in the quartz emission band. This leads to two benefits: (1) more grains can be accepted for equivalent dose analysis, and (2) OSL responses on individual grains are determined with a greater precision. While these three alternative filter combinations perform equally well if compared to each other, we suggest the 2.5mm thick Hoya U340 to be the filter of choice as it allows the use of blue-diode and IR-diode stimulation sources for bleaching purposes and feldspar detection. [Copyright &y& Elsevier]

We explore the use of quartz optically stimulated luminescence (OSL) dating for reconstructing coastal evolution on a time scale of decades to a few hundred years. Samples are taken from the accretionary south-west coast of Texel, a barrier island just offshore of the northern Netherlands. The ages of dune ridges are known from historical sources; an excellent chronology with a decadal accuracy exists for the past 260 years. OSL ages of less than 10 years on the youngest samples indicate that the OSL signal of the quartz grains is very well zeroed prior to deposition and burial. OSL ages of five samples from a 250-year-old dune ridge are indistinguishable, and the OSL ages on 17 out of 20 samples are in excellent agreement with the well-known independent age controls. Our results highlight the potential of OSL dating for high-resolution reconstruction of coastal evolution over the past few centuries. [Copyright &y& Elsevier]