Reliability study on ESR dating of the aluminum center in quartz

The ESR signal of the aluminum center in quartz was historically used to provide the age of geological or archeological material. For this study, pure artificial quartz was divided into several aliquots, after sieving to 30–50μm. Before being given a range of doses, each aliquot was given an unknown dose to act as the palaeodose. The unknown dose was determined using three reference alanine dosimeters that were irradiated together with each aliquot of pure quartz. This unknown dose was determined using the additive dose method. As the aluminum center shows a complex spectrum with 14 peaks, the possibility of using different peak-to-peak heights for ESR readout has been investigated. Our results demonstrate no saturation of the aluminum signal even after irradiation up to 60,000 Gy; this implies that ESR dating using the aluminum center has great potential for dating sediments of over 2 Ma. We conclude that peak-to-peak heights of both 1–6 (the height from the top of the first peak to the end of the sixth peak) and 1–14 (the height from the top of the first peak to the end of the last peak) can be used for ESR readout of the aluminum center. Our data obtained for different temperatures of ESR analysis showed possible problems due to the peroxy center and the E1′E1′ center overlapping the aluminum center.