OSL (Optically Stimulated Luminescence)
Definition
A dating method that measures the accumulated radiation dose stored in mineral grains (usually quartz or feldspar) since they were last exposed to sunlight. Gives the date of sediment burial or the last disturbance by light, not the burial of an organic body.
- Measures
- Accumulated radiation dose in mineral grains
- Typical minerals
- Quartz or feldspar
- What it dates
- Time since last exposure to sunlight (sediment burial)
- Not a measure of
- Time since burial of an organic body
Common questions
Why can't OSL directly date when a body was buried?+
OSL dates the mineral grains in the surrounding sediment, recording when those grains were last exposed to light during disturbance, not the biological age of any organic remains placed among them; the two events can differ.
How is OSL useful in a clandestine grave investigation if it does not date the body?+
It can establish when the soil at a suspected grave site was last disturbed by digging, which helps corroborate or challenge a claimed burial date independent of any decomposition-based estimate.
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