Improved methodology and new thermoluminescence ages for the dune sequencein south-east South Australia

Our thermoluminescence dating technique for quartz extracted from late Plei stocene sediments has been improved by the addition of a 33 h 160 degreesC preheat before measurements. This yields better plateaux, which now encompa ss the region known as the 325 degreesC TL peak; this is consistent with th e prediction, from isothermal decay studies, of the lifetime at ambient tem perature of the traps responsible for this peak. The preheat does not help resolve problems associated with dose responses above 600 Gy. Some details of the dose response are shown to be better understood with the aid of 3-D TL spectra. The improved method has been applied to one former and seven ne w samples from the stranded beach-dune sequence in south-east South Austral ia. The five ages obtained for the main dune sequence range from 95 +/- 6 t o 725 +/- 100 ka and all are consistent with the expected ages. (C) 2000 El sevier Science Ltd. All rights reserved.