RESEARCH METHOD
pOSL & luminescence profiling
Portable optically stimulated luminescence for rapid tracking of relative signal changes through a profile.
01
What the method shows
Relative changes in luminescence signal through a profile as a rapid indicator of sedimentary and stratigraphic change.
How we use it in HEL
For dense vertical transects and checking hidden stratigraphy, especially together with pXRF and field profiles.
02
How the method works
In our workflow pOSL means portable optically stimulated luminescence. A sample is optically stimulated and a detector records photons emitted by mineral grains; the result is luminescence intensity rather than a numerical age.
Dense sampling through a profile can reveal abrupt or gradual signal shifts. These may reflect depositional history, prior light exposure, mineralogy or sediment mixing and help test whether a macroscopically weak profile contains separable units.
pOSL is a relative proxy. Photon counts cannot be converted directly into age, nor should every signal shift automatically be treated as a stratigraphic boundary.
pXRF, field stratigraphy, micromorphology and, where absolute age is required, laboratory OSL dating.
03
In practice
- Input / materialsediment sampled for portable luminescence measurement
- Scale / resolutiondense depth profile; in HEL a series of samples through the profile
- Sampling / preparationregular transect tied to stratigraphy and other proxies
- Typical outputrelative photon-count depth trends and a check of stratigraphic integrity
04
Limits and control
pOSL is not, by itself, absolute dating; mineralogy, transport, light exposure and depositional history affect the signal.
Tel Burna: checking stratigraphic integrity and recognising destruction and architectural signals.
05
References and HEL studies
Selected studies underpinning the method descriptions and examples used by Human Earth Lab.