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In this study, the optically stimulated luminescence dating technique was used to determine the time of deposition of alluvial sediment samples from the Türkoğlu-Antakya segment of the East Anatolian Fault System (EAFS) in Turkey. The double-single aliquot regenerative dose protocol on fine grain samples was used to estimate equivalent doses (De). Annual dose rate was computed using elemental concentration of uranium (U) and thorium (Th) determined by using thick-source alpha counting and potassium (K) concentrations using X-ray fluorescence and/or atomic absorption spectroscopy. The environmental dose was measuredin situusing α-Al2O3:C chips inside plastic tubes for a year. The two different bulk sediment samples collected from the Islahiye trench yielded ages of 4.54 ± 0.28 and 2.91 ± 0.23 ka. We also obtained a 2.60 ± 0.18 ka age for the alluvial deposit in the Kıranyurdu trench and 2.31 ± 0.14 ka age for an excavation area called Malzeme Ocağı. These ages were consistent with the corresponding calibrated Carbon-14 (14C) ages of the region. The differences between the determined ages were insufficient to clearly distinguish the disturbance event from the effects of bioturbation, biological mixing, or other sources ofDevariation in the region. They provide a record of alluvial aggradation in the region and may determine undocumented historical earthquake events. [ABSTRACT FROM PUBLISHER]

In this article, we have investigated the effects of pre-irradiation heat treatments on the thermoluminescence (TL) glow peaks of natural fluorite (CaF2) collected from the central Anatolia region of Turkey. A typical TL glow curve of phosphor consists of four clear glow peaks with maximum intensities occurring at temperatures around 100 °C, 120 °C, 190 °C and 290 °C for a sample irradiated to a dose of 48 Gy and readout at a heating rate of 1 °C/s. It was observed that the intensities of all the TL glow peaks are strongly sensitive to annealing temperatures and durations. Annealing at 450 °C for 15 min was found to be the best for reproducibility of experimental results. The dose-responses of individual TL peaks of this material were also examined after annealing at 450 °C for 15 min by β-irradiation to doses between 0.04 Gy and ≈10.4 kGy. It was observed that the total area and peak heights of all glow peaks showed similar trends with increasing radiation dose; first, they increased linearly up to ≈50 Gy and then saturation effects began above this dose value. The effect of heating rate on the TL glow peaks of the mineral was also studied and it was observed that the intensities of glow peaks are differently affected with variation in heating rate. [ABSTRACT FROM AUTHOR]