Osl dating sheffield
For this purpose, optically stimulated luminescence (OSL) dating, among other dating techniques, has been used in order to establish accurate chronology.More than 150 samples from glacial environments have been dated and provide key information for modelling of the ice retreat.Measurements have been performed on different luminescence readers to study the possible contribution of instrument reproducibility.These have shown that a great variability can be observed not only among the studied samples but also within a specific site and even a specific sample.
Specific statistical approaches have been used to over come the former to enable the estimated ages to be based on grain populations most likely to have been well bleached.This makes it an extremely valuable technique for dating landforms deposited by the wind, rivers and glaciers.Put in slightly more technical terms it uses a light-sensitive signal that has built up in sand grains from exposure to background radiation (see this acceisble quick fact sheet and this excellent set of guidelines written by Geoff Duller).For example, if the question was ‘how dyanmic was dune accumulation and migration over the past 5,000 years’ we could rapidly make measurements on small amounts of material in the field to target those parts of the 34,000 km^2 of the Namib Sand Sea that were about 5,000 years old or less.Then we would need only to sample those areas and depths into the sand dunes.
This may be because the sites we have chosen, all inside the Namib Sand Sea have a common sedimentary origin. We are not advocating that this should be done instead of full optically stimulated luminescence dating, with full sample preparation and full analytical protocols (time-intensive as it is, including lots of time in the dark laboratory).