Grains are then optically stimulated by blue, green or infrared photons, and the OSL emissions are detected using a photomultiplier tube.For single-grain analysis, individual grains are deposited in holes drilled into custom-made discs and a focussed laser beam is shone into each hole (photos: Risø National Laboratory and Bert Roberts).
The laboratory has two portable gamma-ray spectrometry units to measure the on-site dose rate from gamma radiation, and laboratory determinations of sample radioactivity can be made using a Risø GM-25-5 low-level beta-counting unit and three Daybreak 583 thick-source alpha counters.Ph D students and postdoctoral researchers are encouraged to become proficient in OSL sample preparation and measurement procedures, and in the analysis and interpretation of the resulting data.Grains of quartz or feldspar are mounted on stainless steel or aluminium discs and loaded into the instrument.Up to 48 discs can be measured in a single automated sequence.Many different laboratory protocols have been developed as our understanding of the fundamental behaviour of luminescence signals from quartz and feldspar has improved.
These protocols are explained and discussed, giving the advantages and disadvantages of each procedure as applied to different types of sediment.
The OSL dating laboratory is located in the School of Earth & Environmental Sciences and is headed by Bert Roberts and Zenobia Jacobs.
It is recognised as one of the world’s leading archaeological dating laboratories, based on its track record of using OSL dating to answer internationally significant questions in archaeology and palaeoanthropology.
These samples are then dated, and the age information is used to help und The Luminescence Dating Laboratory’s primary function is to conduct original research, but it is also a teaching laboratory.
The laboratory’s director and our post-doctoral fellow, Dr.
For sediments some new problems were encountered, with some grains perhaps not being completely bleached at deposition.