Osl dating method
The radiation causes charge to remain within the grains in structurally unstable "electron traps".
The trapped charge accumulates over time at a rate determined by the amount of background radiation at the location where the sample was buried.
Scientists dating Quaternary glacial sediments in Antarctica most commonly use one of the methods outlined below, depending on what kind of material they want to date and how old it is.
Cosmogenic nuclide dating is useful for directly dating rocks on the Earth’s surface.
The OSL (optically stimulated luminescence) dating method exploits dosimetric properties of grains of minerals naturally occurring in sediments and man-made materials.
In archaeology the OSL method is used to date pottery and other heated materials (e.g., bricks, stones, earth) or sediments related to archaeological finds.
There are so many other methods of dating Quaternary sediments and organic material that it is impractical to cover them all here in detail.
Stimulating these mineral grains using either light (blue or green for OSL; infrared for IRSL) or heat (for TL) causes a luminescence signal to be emitted as the stored unstable electron energy is released, the intensity of which varies depending on the amount of radiation absorbed during burial and specific properties of the mineral.
Most luminescence dating methods rely on the assumption that the mineral grains were sufficiently "bleached" at the time of the event being dated.
It assumes that boulders have not been buried and then re-exposed at the Earth’s surface.
Radiocarbon dating dates the decay of Carbon-14 within organic matter.
It is useful to geologists and archaeologists who want to know when such an event occurred.