A single-aliquot OSL protocol using bracketing regenerative doses to accurately determine equivalent doses in quartz

In most cases, sediments show inherent heterogeneity in their luminescence behaviours and bleaching histories, and identical aliquots are not availabl e: single-aliquot determination of the equivalent dose (ED) is then the app roach of choice and the advantages of using regenerative protocols are outl ined. Experiments on five laboratory bleached and dosed quartz samples, fol lowing the protocol described by Murray and Roberts (1998. Measurement of t he equivalent dose in quartz using a regenerative-dose single aliquot proto col. Radiation Measurements 27, 171-184), showed the hazards of using a sin gle regeneration dose: a 10% variation in the regenerative dose yielded som e equivalent dose estimates that differed from the expected value by more t han 5%. A protocol is proposed that allows the use of different regenerativ e doses to bracket the estimated equivalent dose. The measured ED is found to be in excellent agreement with the known value when the main regeneratio n dose is within 10% of the true equivalent dose. (C) 1999 Elsevier Science Ltd, All rights reserved.